Received: 3 July 2021 Accepted for publication: 3 January 2022 Slov Vet Res 2022; 59 (1): 5–29 DOI 10.26873/SVR-1354-2022 UDC 616.993.19-078:616-039.71:598.2 Review Article Introduction Cryptosporidiosis is a zoonotic enteric parasitic disease affecting humans, mammals, birds, and fish (1, 2). Globally, cryptosporidiosis is ranked fifth among the 24 most important foodborne parasites (3-5). Avian species could be infected with Cryptosporidium parasite with variable mortality and morbidity rates, causing great economic losses (6-10). The most important pathogenic species of Cryptosporidium that affect birds are Cryptosporidium meleagridis (C. meleagridis), C. baileyi, C. galli, and C. avium (11). In chickens and/or turkeys, infection is usually caused by C. baileyi and C. meleagridis (12), and rarely C. parvum (13) and C. galli (14). There are great differences in the prevalence and distribution rates of AVIAN CRYPTOSPORIDIOSIS: A SIGNIFICANT PARASITIC DISEASE OF PUBLIC HEALTH HAZARD Wafaa A Abd El-Ghany Poultry Diseases Department, Faculty of Veterinary Medicine, Cairo University, Giza, 12211 Giza Square, Egypt *Corresponding author, Email: wafaa.ghany@yahoo.com Abstract: Cryptosporidiosis is one of the most important zoonotic parasitic diseases affecting a wide range of host species. The disease is widely distributed all over the world. Cryptosporidium species can affect different avian hosts, causing severe economic losses. The severity of avian cryptosporidiosis symp-toms vary from asymptomatic disease to severe enteric and/or respiratory manifestations with high mortality. Diagnosis of Cryptosporidium infection is mainly based on microscopic detection of oocysts, serological methods, or molecular techniques to identify different Cryptosporidium species. Humans and animals are highly susceptible to infection by different Cryptosporidium species as a result of the ingestion of contaminated food and water by oocysts or direct contact with infected hosts. Different prevention and control strategies have been applied either in the sur- rounding environment or for the infected animals, birds, and humans. Therefore, this review article was designed to shed light on avian cryptosporidiosis species and its distribution, susceptibility and infection, clinical pictures, laboratory diagnosis, zoonotic importance in humans, and prevention and control strategies. Key words: avian; control; Cryptosporidium; diagnosis; human Cryptosporidium species among various avian species. The clinical pictures of Cryptosporidium infections vary from intestinal to respiratory diseases according to the oocysts of each species, susceptibility and age of the birds, and presence of concurrent infections (15). Conventional microscopical staining techniques (16), serological methods, and recent molecular techniques are used for the diagnosis of cryptosporidiosis (17, 18). Several studies around the world demonstrated the zoonotic potential of Cryptosporidium species like C. parvum, C. hominis, and C. meleagridis in different hosts like dogs, cattle, mice, and cats. Humans, especially children and patients with immunodeficient diseases, could be infected through direct contact with infected animals (19) or birds (20). Application of hygienic measures, prevention of direct contact with infected animals or birds, and treatment of infected Zbornik_1_2022_22.4.22.indd 5 22/04/2022 09:53:31 6 W. A. A. El-Ghany animals, especially diarrheic animals or humans, are the most important strategies for the prevention and control of cryptosporidiosis. Accordingly, this review article was designed to shed light on avian cryptosporidiosis distribution, susceptibility and infection, clinical pictures, labo- ratory diagnosis, zoonotic importance in humans, and prevention and control strategies. History and distribution Table 1 show the incidence and distribution of Cryptosporidium species in different avian hosts all over the world. The first detection of avian Cryptosporidium oocysts was in the cecum of apparently healthy chickens (21) as these oocysts were similar to C. parvum and C. hominis in humans. Later, for the first time, a unique Cryptosporidium species was described as C. meleagridis by Slavin (22), and this species was molecularly differentiated from C. parvum as a different avian species with zoonotic nature (23). In an Algerian study by Baroudi et al. (24), the prevalence rates of C. meleagridis were 57.9%, 43.9%, and 5.5% in turkey poults, adult turkeys, and broiler chickens, respectively. However, the infection rate of C. meleagridis in chickens of the previous study was 28.9%. Furthermore, C. meleagridis was previously found in 5% (25), 3% (26), and 3.2% (27) of broiler chickens and 10% of layer chickens in China (28) and in 9% of broilers in Algeria (29). Another species of Cryptosporidium called C. baileyi was detected in the intestinal tracts, bursae of Fabricius, and cloacae of birds (30), in the upper and lower respiratory tracts of broilers (31, 32, 26) and geese (33), and in the urinary tract as kidneys (34, 35). Recently, C. baileyi was molecularly detected in broiler and layer chickens, ducks, and pigeons as a zoonotic species (36, 27, 37). It has been documented that C. baileyi is the most prevalent avian Cryptosporidium species worldwide and has a wide host range (38-41, 28, 11, 42). Although C. parvum has zoonotic importance in humans, it is sporadically found in poultry species (11). In 2017, in Germany, the prevalence rates of Cryptosporidium species were 5.7% in broilers and 8.3% in layers, and C. parvum was the most predominant isolate of chickens and turkeys (20, 40). In Brazil, C. parvum was detected in chicks (15), while in the Unites States it was detected in turkeys (43). Other species of Cryptosporidium have also been identified earlier. Levine (44) found C. tyzzeri in chickens, while Proctor and Kemp (45) found C. anserinum in geese. In 1990, C. blagburni was identified in finches (46, 39), but this species was further described as C. galli with a zoonotic nature. The latter was previously identified in chickens’ proventriculi (47, 48, 14). Different avian species of Cryptosporidium have been reported among Egyptian poultry flocks. The first morphological detection of C. meleagridis, C. baileyi, and C. galli was in quails in 2011. The study showed that the prevalence rates of Cryptosporidium oocysts were 30.8% in bobwhite quails and 33.3% in brown quails with a total percentage of 31.9% (49). From a wide range of avian species in different seasons, Cryptosporidium in all the examined bird species was prevalent in winter (15.4% for fowl, 3.6% for pigeons, 44.2% for ducks, 15.7% for turkeys, and 30% for geese), while the lowest prevalence rate of Cryptosporidium was in spring (8.3% for fowl and 2.6% for pigeons). Cryptosporidium showed less incidence in ducks in autumn (2.4%) and summer (3.2%) and in turkeys (4.4%) (50). In the study of Kalifa et al. (51), the incidence of Cryptosporidium species in ducks was 39.9 %, with the highest rate in winter (74.6%) and the lowest rate in autumn (7.1%). Approximately 55% of 100 ducks had antibodies against cryptosporidiosis. The molecular analysis revealed positive amplification at 435 bp, and sequencing confirmed the presence of C. meleagridis. Genetically, five genotypes of Cryptosporidium (I, II, III, IV, and V) were identified in birds (9, 52). In Canada, genotypes I to V were identified in wild geese and the black duck (53, 54). Genotype I was detected in canaries and Indian peafowl (41, 55). Genotype II was found in ostriches (56, 57) and other several species of Psittaciformes and Pas- seriformes (41, 58-62). Genotype IV was identified in Japanese white-eye woodcocks, in addition to the Eurasian woodcock genotype that was de- tected in Eurasian woodcocks (41). Genotype V was found in cockatiels (52), Psittaciformes (59, 62), and reptiles (63). Phylogenetically, C. melea- gridis, C. baileyi, goose genotypes I and II, and the duck genotype belong to the Cryptosporidium in- testinal clade, while C. galli, C. andersoni, C. muris, C. serpentis, and genotypes III and IV belong to the gastric clade (64, 41). Zbornik_1_2022_22.4.22.indd 6 22/04/2022 09:53:31 7Avian cryptosporidiosis: a significant parasitic disease of public health hazard Table 1: Incidence and distribution of Cryptosporidium species in different avian hosts all over the world Country Incidence and distribution Reference Brazil C. baileyi, C. galli, and C. meleagridis have been characterized in ostriches using morphological, biological, and molecular techniques. [9] C. baileyi was found in ducks and quail, while C. melagridis was detected in chicken. [36] Positive amplification for Cryptosporidium species was observed in 12.6% (24/190) of the samples, including C. baileyi (9.8%; 18/190), C. meleagridis (0.5%, 1/190), C. parvum (2.1%; 4/190), and Cryptosporidium species (0.5%; 1/190). Sub-genotyping of C. meleagridis revealed the presence of the subtype IIIgA23G3R1. [42] Sequencing of Cryptosporidium species revealed presence of C. baileyi in a black vulture, a domestic chickens, and a saffron finch; C. galli in canaries, a cockatiel, and lesser seed- finches; C. meleagridis in a domestic chicken; C. parvum in a cockatiel; Cryptosporidium avian genotype I in a canary and an Indian peafowl; Cryptosporidium avian genotype II in ostriches, and Cryptosporidium avian genotype III in a cockatiel and a peach-faced lovebird. [55] Molecular analysis of nucleotide sequences grouped the ostrich isolate of Cryptosporidium species as C. baileyi which was genetically distinct from all other species. [56] Among the 242 fecal samples from wild birds, 16 (6.6%) were positive for the presence of Cryptosporidium. Molecular characterization of 16 samples showed C. meleagridis. C. galli was identified in rufous-bellied thrush, green-winged saltators, slate-coloured seedeater, goldfinch, and saffron finches. Isolates in Goldfinch isolate, buffy-fronted seedeater, red- cowled cardinal, and saffron finch isilates were identified as C. baileyi. Avian genotype II was found in an isolate from a white-eyed parakeet. [60] Out of 103 fecal samples of exotic birds, 7 (6.8%) were positive for Cryptosporidium. Sequencing analyses showed C. parvum in Bengalese finch and avian genotype III in Java sparrow and cockatiel. The sequences of the Cryptosporidium species isolated from canaries presented a higher genetic similarity with C. parvum. [61] A total of 1027 fecal samples were collected from Psittaciformes and Passeriformes. Molecular analysis showed positive results in 580 (56.47%) and 21 (2.04%) samples, respectively, for C. galli and Cryptosporidium avian genotype II, and in 28 (2.73%) and 3 (0.29%) samples, respectively, for C. galli and Cryptosporidium avian genotype III. C. baileyi and Cryptosporidium avian genotype V were also identified. [62] Microscopic examination of fecal smears of carrier pigeons revealed presence of 4% (4/100) positive Cryptosporidium. While, 7% (7/100) were molecularly positive. C. parvum was genetically identified. [75] C. baileyi was identified in broiler chickens. This species was able to infect Japanese quails. [79] Cryptosporidium was observed in 44.4% of the examined 77 ostriches. However, 100% of the ostriches shed oocysts in their feces. [86] C. galli infection was microscopically, histologically, and molecularly characterized in canaries, a cockatiel, and in lesser seed-finches with clinical complaints of apathy and sporadic mortality. [134] Cryptosporidium species were detected in 24.5% samples of adult and 13% of young species of birds including great-billed seed-finch, lesser seed-finch, ultramarine grosbeak, and rusty- collared seedeater. The sequencing analyses showed identification of C. galli. The protozoon infection was associated with concomitant infection with Escherichia coli and Isospora species. [135] Zbornik_1_2022_22.4.22.indd 7 22/04/2022 09:53:31 8 W. A. A. El-Ghany Table 1: continnuation The United states Genotypes I to V of Cryptosporidium were identified in wild geese. [53] Cryptosporidium goose genotype I, Cryptosporidium goose genotype II, Cryptosporidium duck genotype, C. parvum, and C. hominis were identified. [54] Oocysts of Cryptosporidium species were observed in the feces, and the developmental stages of the parasite were observed in tissue sections of turkeys and Muscovy ducks but not bobwhite quail. [66] Oral inoculation of ducks with C. baileyi induced no clinical signs, while intratracheal inoculation produced mild respiratory disease, no deaths, and airsacculitis. [69] Proventriculus and intestinal samples from 70 North American red-winged blackbirds were examined. Twelve birds (17.1%) were genetically positive for the Cryptosporidium. Sequence analysis of the gastric species revealed presence of C. galli and Cryptosporidium avian genotype VI. [90] Microscopic examination of the intestinal contents of turkey poults suffering from diarrhea and mucoid enteritis and typhlitis showed presence of Cryptosporidium species in the enterocytes, villi atrophy, and infiltration with inflammatory cells. [95] Cryptosporidium oocysts were detected in the droppings of 16/20 (80%) 17-day-old and of 38/100 (38%) 24-day-old turkeys without signs. The protozoon was frequently found in the ceca, colon, and cloaca of inoculated turkeys and chickens. [98] Outbreaks of sinusitis due to Cryptosporidium were documented in 7-and 3-week-old turkeys. [100] Concurrent infection with Mycoplasma sturni and Cryptosporidium species was detected in cliff swallows manifested clinical, gross, and microscopic lesions. [106] Mixed infection with C. baileyi and infectious bursal disease virus resulted in more severe bursal lesions, more infected birds, and greater numbers of the parasite in infected tissues. [114] Double infection with C. baileyi and either reovirus promoted shedding of both. Reovirus infection did not modify lesions caused by C. baileyi infection. [115] Cryptosporidium infection promoted systemic spread of reovirus, and reovirus intensified Cryptosporidium infection, but no significant synergistic effect on mortality or weight gain was observed. [126] Cryptosporidium species were detected during histologic examination of small intestine from a budgerigar with chronic weight loss and from a cockatiel that died acutely. [128] C. baileyi was microscopically detected in the small intestine of cockatiels. [129] Cryptosporidium avian genotype III was demonstrated in lovebird (Agapornis species) manifested gastrointestinal signs ad lesions. [136] Mixed infection with adenovirus and Cryptosporidium species was demonstrated during examination of tracheal mucosa of 7-week-old broiler chickens that had excessive exudate in the tracheas and congestion of the nasal turbinates. [139] Cryptosporidium species were microscopically demonstrated in young quails experienced high mortality, diarrhea, and clear fluid content in the intestine. [6] Cryptosporidium species and reovirus were identified in bobwhite quails with white-watery diarrhea, dehydration, and death, 30%-45% mortality rate, and mucoid enteritis. [7] The overall 23 of 56 (41%) broiler chickens had C. baileyi tracheitis. The infection rates among C. baileyi-infected flocks ranged from 10%-60%. [32] Cryptosporidium species were microscopically detected in the urinary tract of adult laying hens. [35] C. parvum was found in turkeys, especially in 4-9-week-old birds. [43] Zbornik_1_2022_22.4.22.indd 8 22/04/2022 09:53:31 9Avian cryptosporidiosis: a significant parasitic disease of public health hazard Table 1: continnuation Australia The phylogenetic analysis supported the existence of C. baileyi and C. meleagridis in finches, a black duck, and brown quail. [39] Of 430 avian-derived fecal specimens, 27 Cryptosporidium-positive isolates were detected and characterized. Genotypes I to IV were molecularly identified. C. galli, C muris, and C. andersoni were also identified in a tawny frogmouth and a quail-crested wood partridge. [41] Cryptosporidium infection was found in 4-week-old quails with respiratory lesions and shrunken bursa of Fabricius. Deciliation, hyperplasia, and inflammatory cell infiltration in the respiratory cells and in the oesophageal and salivary glands were detected. Besides, follicular bursal atrophy and presence of Cryptosporidium species were observed. [76] Cryptosporidium associated conjunctivitis was detected in 8-week-old ducks with conjunctivitis. [101] Respiratory cryptosporidiosis was diagnosed in a 2-week-old peacock chicks. Microscopic examination of conjunctiva, nasal-sinus, and trachea showed the different developmental stages of Cryptosporidium. [104] C. meleagridis was detected in an Indian ring-necked parrot using morphological and molecular methods. [130] Histological examination and antigenic diagnosis by enzyme-linked immunosorbent analysis revealed the presence of Cryptosporidium species in respiratory and intestinal tracts of red- legged partridges. Morbidity (diarrhoea and cough) was 60%-70% and mortality was 50%. C. meleagridis was molecularly identified in faecal samples. [10] Spain Intestinal cryptosporidiosis was identified in young pigeons manifested diarrhea and body weight loss. Hyperplasia of the intestinal crypts with inflammatory infiltration were seen. [71] An ocular and respiratory disease were associated with C. baileyi infection in wild scops owl. Molecular analysis confirmed the presence of C. baileyi in the conjunctival cells and the nasal respiratory epithelium. [89] Canada Developmental stages of Cryptosporidium were observed in tracheal epithelium of turkey poults. Lesions associated with the parasite included excess mucus, epithelial hyperplasia, metaplasia, and necrosis, and infiltration with macrophage and heterophil in thickened lamina propria. [65] Cryptosporidium species were found in the feces of 14 out of 165 (8.5%) ostriches. The oocysts failed to infect chickens, turkeys, or quail. Cryptosporidium species from ostriches was different from C. meleagridis, C. baileyi, and Cryptosporidium species of bobwhite quail. [82] Scotland Ziehl-Neelsen staining of the fecal smears, bursae of Fabricius, or respiratory organs of broilers revealed infection rates of 18.7% of Cryptosporidium species. [16] C. baileyi was molecularly identified in wild red grouse with sinusitis, conjunctivitis, and swollen head. [105] The Czech Republic C. galli was isolated from the stomach of hens and it was transmitted from hens to chickens. [48] C. baileyi was identified in 15 out of the 22 avian-derived isolates, while C. meleagridis was identified in 5 avian-derived isolates. One isolate (B1-30), from a rose-ringed parakeet, exhibited a mixed infection of both C. meleagridis and C. baileyi. [138] Germany C. baileyi was microscopically and molecularly identified from raptors and from a German falcon breeder with a history of respiratory distress. [88] England C. baileyi was detected in red grouse moors with bulgy eye signs. [108] France C. baileyi infection didn’t prevent the induction of immunity against Marek‘s disease virus serotype 1 vaccine (CVI988/Rispens) in chickens. [112] Hungary Chicken anemia virus infection may increase the reproductive potential of C. baileyi in chickens and both pathogens have synergistic effect on each other. [113] The Nether- lands Cryptosporidium infection was associated with colitis and cystitis in green iguanas. The disease was characterized by cloacal prolapses and cystitis. Based on molecular gene identification, Cryptosporidium species were c belonging to the intestinal Cryptosporidium lineage, but not to C. saurophilum or C. serpentis. [63] Denmark In 73 of 128 ducklings, and in 44 of 74 goslings, Cryptosporidium species were detected. Tissues from the bursa of Fabricius were positive in both species of birds. The presence or absence of the parasite could not be correlated with clinical signs or lesions and/or poor performance of the birds. [68] Zbornik_1_2022_22.4.22.indd 9 22/04/2022 09:53:31 10 W. A. A. El-Ghany Table 1: continnuation Poland A total of 499 fecal dropping from 308 free-ranging, 90 captive, and 101 domestic birds were tested by conventional, immunological, and molecular techniques for Cryptosporidium. C. parvum was found in 19 (3.8%). [93] Greece C. baileyi was molecularly identified in 7-week-old Saker falcon died with a history of severe respiratory signs and lesions and otitis media. [107] Ziehl-Neelsen staining of the fecal smears, bursae of Fabricius, or respiratory organs of broilers showed infection rates (24.3%) of Cryptosporidium species. [142] South Africa Heavy infection of the cloacal and bursal tissues with Cryptosporidium species was observed in ostriches showed phallus prolapse as well as in normal birds. Loss of the microvilli borders, epithelial hyperplasia, swelling of organelles, and nuclear changes were detected microscopically. [84] The histological findings in emaciated 4-month-old ostriches revealed presence of Cryptosporidium species in the necrotic and inflamed pancreatic epithelium. [127] Nigeria The total prevalence of Cryptosporidium oocysts was 7.4% in different avian species. Local birds had the highest prevalence rate (9.5%), followed by exotic birds (6.6%) and the wild ones (5.3%). [4] China The infection rate of Cryptosporidium among broiler chicken was 10% (38/385). C. baileyi, C. meleagridis, and Cryptosporidium avian genotype II were molecularly identified. [25] The overall infection rate of Cryptosporidium was 10.6% (163/1542) in layer chickens, 3.4% (16/473) in broilers, and 16.3% (92/564) in Pekin ducks. C. baileyi (184/187) on chicken and duck farms, and C. meleagridis (3/187) on layer chicken farms were detected. [28] C. baileyi (33/471; 7.0%) and C. meleagridis (15/471; 3.2%) were identified in broiler chickens. Two subtypes of C. meleagridis including IIIbA26G1R1b and IIIbA22G1R1c were characterized. [27] The overall prevalence of Cryptopsoridium in psittacine birds was 8.1% (35/434). Three Cryptosporidium species and two genotypes were identified, including C. baileyi (18/35 or 51.4%) in red-billed leiothrixes, white Java sparrows, common mynas, zebra finches, a crested Lark, a Gouldian finch, and a black-billed magpie; C. meleagridis (3/35 or 8.6%) in a Bohemian waxwing, a Rufous turtle dove, and a fan-tailed pigeon; C. galli (5/35 or 14.3%) in Bohemian waxwings and a silver-eared Mesia; Cryptosporidium avian genotype III (3/35 or 8.6%) in cockatiels and a red-billed blue magpie; and Cryptosporidium avian genotype V (6/35 or 17.1%) in cockatiels. [59] The overall prevalence of Cryptosporidium infection in pigeons was 0.82% (2/244). C. baileyi and C. meleagridis were identified. [74] The overall prevalence of Cryptosporidium in quail was 13.1% (29 of 47 farms). The highest prevalence was observed in autumn and the lowest in winter. C. baileyi and C. meleagridis were molecularly detected. [78] C. baileyi infection in baby chicks may induce bursal atrophy, immunosuppressive effects against avian influenza (H5N1), and increase the susceptibility to the virus. [121] A total of 303 fecal samples were collected from ostriches and 31 samples (10.2%) were Cryptosporidium-positive upon microscopic analysis. The infection rate was 27.6% in ostriches aged 16-60 days, 1.2% in those aged 61-180 days, and 20.4% in those aged >10 years. Genetic analysis of the isolated parasite revealed presence of C. muris and C. baileyi. [137] Japan Eleven Cryptosporidium isolates were identified molecularly in cockatiels. Three new genotypes in C. meleagridis, avian genotype III, and a new avian genotype V were characterized. [52] Cryptosporidium avian genotype III was molecularly identified in peach-faced lovebirds. [58] Mixed infection with Mycoplasma gallisepticum and Cryptosporidium species or other bacteria was detected in Japanese quail. Birds showed swelling of the head, nasal discharge, increased lacrimation, decreased egg production, mortality rate of 5.7% per day, caseous exudate in the sinuses, egg peritonitis, and airsacculitis. Microscopically, non-purulent or purulent inflammation accompanied by lymphoid hyperplastic tissue with germinal centers were observed in the oculofacial respiratory mucosa. [77] Korea Infection with C. baileyi induced an immunosuppressive effect on Newcastle disease virus vaccine in 2-day-old chicks and the infection with the parasite may increase the susceptibility to this virus infection. [118] C. baileyi infection could suppress the immune response against infectious bronchitis virus vaccine and perhaps increase the susceptibility to this virus infection in chickens. [120] Zbornik_1_2022_22.4.22.indd 10 22/04/2022 09:53:32 11Avian cryptosporidiosis: a significant parasitic disease of public health hazard Malaysia A total of 90 samples were screened for Cryptosporidium from different avian species. Phylogenetic trees identified all the isolates as C. parvum. [94] Bangla- desh Microscopic examination revealed presence of Cryptosporidium species in 19.8% (39/197) of avian specimens. Molecular characterization showed that 15.7% (31/197) of the samples were Cryptosporidium positive. Of these 31 samples, 17 were C. baileyi (8.7%), 12 were C. meleagridis (6.0%), and 2 were C. parvum (1.0%). C. meleagridis had two subtypes (IIIbA21G1R1 and IIIbA23G1R1), which were found in broiler, native and sonali chickens, and a pigeon. Two novel subtypes (IIIbA21G2R1 and IIIbA20G2R1) were identified in sonali chickens, a broiler chicken, and a layer chicken. [37] Vietnam C. baileyi genotype II was detected in 2-3-month-old ostriches with a prevalence rate of 23.7% (110 out of 464 samples). [57] Thailand C. meleagridis was identified in pigeons, however, Cryptosporidium avian genotype III was detected in seagulls. [73] Egypt The prevalence rates of C. meleagridis, C. baileyi, and C. galli were 30.8% in bobwhite quails and 33.3% in brown quails with a total percentage of 31.9%. [49] Cryptosporidium showed less incidence in ducks in autumn (2.4%) and summer (3.2%) and in turkeys (4.4%). [50] The incidence of Cryptosporidium species in ducks was 39.9%, with the highest rate in winter (74.6%) and the lowest rate in autumn (7.1%). Approximately 55% of 100 ducks had antibodies against the parasite. [51] C. baileyi could be one cause of vaccination failure against Newcastle disease and/or avian influenza viruses in chicken’s farms. [119] Iran Cryptosporidium species were identified in pigeons with overall prevalence rate of 2.94%. [72] C. meleagridis was histologically detected in the intestinal tract of turkey poults suffering from diarrhea and unthriftness. The oocyst shedding was detected only in 29% of positive birds. [96] Microscopic examination of the intestine and trachea demonstrated that 23.75% of 240 broiler samples were infected [148] Algeria Cryptosporidium infection rates were 34% and 44% in chickens and turkeys, respectively, with all pos- itive turkeys (25) and most positive chickens (26/31) having C. meleagridis. All C. meleagridis isolates belonged to a new subtype family. [24] A total of 345 faecal samples were collected from domestic, captive, and wild birds. Cryptosporidium species were detected in 31 samples. Sequence analysis revealed the presence of C. baileyi in do- mestic chicken broilers, captive ostriches, and a wild mallard, and C. meleagridis in a graylag goose, chickens, and turkeys. The overall prevalence of Cryptosporidium in chickens and turkeys was 2% and 6%, respectively. Both C. meleagridis and C. baileyi were detected in chicken broilers, with a prevalence ranging from 9% to 69%. Turkeys were positive only for C. meleagridis, with a 13% prevalence at the animal level. Subtyping of C. meleagridis isolates showed subtype IIIgA22G3R1 in graylag goose and chicken broilers and IIIgA23G2R1 in chicken and turkey broilers. [29] Morocco Examination of intestine, bursa of Fabricius, and trachea revealed existence of Cryptosporidium species in 37% of 225 broilers flocks. The prevalence of infection within flocks varied from 14%- 100%. High incidence of Cryptosporidium infection occurred in 36-45-day-old broilers (52%). Cryp- tosporidium species were detected in bursa (24%), intestine (15%), and trachea (2%). In the bursa of Fabricius, Cryptosporidium-induced epithelial lesions, lymphoid atrophy, and depletion. [143] Tunisia Cryptosporidium was detected in 9 out of 200 broiler chicken (4.5%). Molecular characterization showed presence of C. meleagridis in one broiler chicken. [144] Turkey Clinical signs of cryptosporidiosis in 10-day-old pigeon were depression, ruffled feathers, and diar- rhea. Gross lesions were mild hyperaemic segments of small intestine distended with typical green watery ingesta. Cryptosporidium species were found in the villi of lower portions of atrophic and mis- shapen small intestine. [70] Dubai C. parvum was molecularly detected from an outbreak of catarrhal enteritis and mortality among stone curlews. [132] Table 1: continnuation Zbornik_1_2022_22.4.22.indd 11 22/04/2022 09:53:32 12 W. A. A. El-Ghany Susceptibility and infection Cryptosporidiosis has been recorded worldwide in more than 30 species of domestic, wild, and captive birds (23). The disease was demonstrated in chickens, turkeys, ducks, geese, quails, pheasants, ostriches, partridges, and peacocks (65-67, 1). In water fowl (ducks and geese), Richter et al. (68) detected the presence of Cryptosporidium species in the intestinal and respiratory tracts of ducklings and goslings at incidence rates of 57% and 59%, respectively, using indirect immunofluorescence assay. Experimentally, C. baileyi was identified in ducks in Brazil (36). However, C. baileyi was detected using the in situ hybridization technique in the conjunctival and bursal tissues of geese experimentally infected with Usutu virus (33). Moreover, C. baileyi and C. meleagridis could infect the intestine, bursa, and cloaca of ducks after the incubation period up to 9-10 days (69). In pigeons, cryptosporidiosis has been identified by some researchers (70, 71). Qi et al. (59) identified C. meleagridis in one pigeon using molecular techniques, while Radfar et al. (72) found that the prevalence rate of Cryptosporidium species was 3.4% in adult pigeons and 2.3% in squabs. Moreover, cryptosporidiosis infection has been microscopically and molecularly identified in different countries like Thailand (73), China (74), and Brazil (75). In Australia, quails gain natural infection with Cryptosporidium species like C. baileyi and C. meleagridis (76, 39). The natural infection of quails with C. baileyi has been recorded in Japan using molecular techniques (77). Both C. baileyi and C. meleagridis were molecularly characterized in China (78). The experimental infection of quails with C. baileyi isolates of chicken was first unsuccessful (6, 7), while Cardozo et al. (79) succeeded in the induction of infection in quails using isolates of broiler chickens. Infection with C. meleagridis has also been reported in red-legged partridge chicks (10). Ratite bird species also showed susceptibility to cryptosporidiosis. The first detection of Cryptosporidium infections in ostriches was in the 1990s (80, 8, 81-84). Gajadhar (81) identified Cryptosporidium in the feces of 14/165 (8.5%) African ostriches. However, in 1994, Gajadhar (82) investigated these oocysts and the host specificity. The identified oocysts were identical to C. meleagridis, but they were non-infectious to chickens, turkeys, quails, and mice (82). Later on, Ponce Gordo et al. (85) identified Cryptosporidium oocysts in 2-month-old to 5-year-old ostriches, but with a low prevalence rate (2/336, 0.6 %). Microscopically, the prevalence rate of C. baileyi in Europe was 60% in adult ostriches and rheas (85), and that of the Brazilian isolate was 44% in adult ostriches (86). Cryptosporidium avian genotype II species was molecularly identified in ostriches (56, 41), which was similar to the Brazilian isolate of C. baileyi (9). In Vietnam, Nguyen et al. (57) identified Cryptosporidium avian genotype II oocysts of C. baileyi in 2-3-month-old ostriches with a prevalence rate of 23.7% (110 out of 464 samples). Pet birds could be infected with C. galli, C. meleagridis, and C. baileyi. These species have been described as important zoonotic parasites to humans, especially kids (87). In addition, C. baileyi has been isolated from the upper respiratory tracts of three mixed-bred falcons (88). In owls, Molina- Lopez et al. (89) reported an infection with C. baileyi associated with an outbreak of ocular and respiratory diseases. C. galli and novel Cryptosporidium avian genotype VI have been found in North American red-winged blackbirds (90). The age group susceptibility to cryptosporidiosis is variable according to the Cryptosporidium species. It has been proposed that young birds are the most important risk group since their immune system is not yet fully developed (43). The infection rate of Cryptosporidium was 4.9% in 1-20-day- old broiler chickens, 24.6% in 31-60-day-old layer chickens, and 40.3% in 11-30-day-old Peking ducks (28). Moreover, it has been shown that chickens of all ages are susceptible to C. baileyi, while 31-120-day-old layer chickens are more susceptible to C. meleagridis infection (28). In addition, C. baileyi and C. meleagridis were detected in chicken aged above four months (27). In the United States, the infection is predominant in 4-9-week-old turkeys (43). In the study of Helmy et al. (20), infections with Cryptosporidium were noted in 13.8% of 13-20-week-old turkeys, 5.7% of 1-6-week-old broilers, and 8.3% of layer chickens above 20 weeks of age. Perhaps broiler chickens act as a source of cryptosporidiosis disease infection and transmission of oocysts (91). Birds are infected with Cryptosporidium by ingestion or inhalation of sporulated oocysts in contaminated litter, feces, Zbornik_1_2022_22.4.22.indd 12 22/04/2022 09:53:32 13Avian cryptosporidiosis: a significant parasitic disease of public health hazard water, and dust. The main route of Cryptosporidium transmission is the fecal-oral route as oocysts are shed in the droppings, contaminate the soil and water, and thus provide many paths into the food chain (92). Mechanical transmission through migratory birds has also been reported. Although these birds have a low level of Cryptosporidium infections, they shed oocysts and contaminate the environment (93). Moreover, asymptomatic birds act as a mechanical source of transmission of infective oocysts to other birds, animals, and humans (94). Poor hygienic measures are associated with increased incidence of the infection in poultry flocks (15). Clinical picture The severity of Cryptosporidium clinical disease in poultry depends on birds’ hygienic conditions, stocking density, crowding, and mixing of different ages and species of birds (15). Intestinal Cryptosporidium infection is characterized by diarrhea, lowered weight gain, and distention of the intestinal lumen with mucus and gases, in addition to the presence of different stages of Cryptosporidium in different parts of the small intestine (95, 96). Infection of turkeys with C. meleagridis presents either subclinically (97, 98) or clinically in the form of enteritis (22, 95, 99). C. meleagridis may infect chickens (69) with intestinal involvement. It has been shown that C. baileyi mainly affects the respiratory and intestinal tracts of poultry (38, 40). Reports of C. baileyi respiratory tract infections have been detected in chickens (31), turkeys (100), ducks (101, 102), geese (33), and pheasants (103). In addition, some wild birds, such as falcons, owls, swallows, and the red grouse, showed infection of the upper respiratory system, middle ear, and eyes with C. baileyi (104, 88, 89;105-108). Co-infection of C. baileyi with Escherichia coli and infectious bronchitis (IB) virus was reported, and the affected birds showed mortality associated with lower respiratory tract infections, such as bronchitis, pneumonia, and air sacculitis (109-111). Moreover, C. baileyi is associated with other causative agents with high mortality and lowered body weight gain. Among these infectious agents are the virus vaccine of Marek’s disease (MD) (Rispens) (112), chicken infectious anemia virus (113), infectious bursal disease (IBD) virus (114), and reoviruses (115). In addition, it has been reported that C. baileyi induces humoral immuno-suppression effect through the infection of the bursa of Fabricius (116). This effect is controversial and shows different results. For example, the infection of chickens with C. baileyi suppresses the immune response to the virus vaccines of MD (117, 112), IBD (114), reoviruses (115), Newcastle disease (118, 119), IB disease (120), and avian influenza disease (121, 119). Although the experimental challenges of chickens with C. baileyi induced purulent bursitis and hyperplasia as well as slight lymphoid atrophy (122, 123), no effect on the humoral immune response has been detected (110, 123). Severe sinusitis with a morbidity rate of 5%- 10% was observed in young turkey poults infected with Mycoplasma species (100). Respiratory signs were observed in thirteen turkeys that were histologically positive for Cryptosporidium species (124). However, a history of self-limiting diarrhea was identified in a flock of turkey poults suffering from invasive Cryptosporidium (95). In Iran, C. meleagridis oocysts were detected in diarrheic unthrifty turkey poults (96). Sneezing, frothy eyes, swollen sinuses, coughing, and rattling were reported in a case of C. baileyi and C. meleagridis infections in turkeys (125). Cryptosporidium species were detected in five- day-old quails with high mortality (6). Ritter et al. (7) reported a mortality rate up to 45% that was associated with acute fatal diarrhea in 1-17-day- old quails as the infection was associated with Cryptosporidium and reovirus. A similar study was carried out by Guy et al. (126) who observed severe diarrhea and mortality as well as high oocyst shedding after the experimental coinfection of quails with Cryptosporidium and reovirus. Respiratory signs and lesions, drop in egg production with peritonitis, and a daily mortality rate of 5.7% were reported in Japanese quails due to mixed infection with Mycoplasma gallisepticum and Cryptosporidium species (77). However, in a study of Wang et al. (78) in China, no signs were detected in a Cryptosporidium-positive quail flock. In pigeons, invasive stages of Cryptosporidium were identified in the intestine of a pigeon with depression, and diarrhea soiled the feather around the vent (70). Moreover, yellow watery diarrhea, weight loss, and dehydration were associated with 40% morbidity and 5% mortality rates (71). Diarrhea, cough, morbidity rates of 60-70%, and a mortality rate more than 50% were reported Zbornik_1_2022_22.4.22.indd 13 22/04/2022 09:53:32 14 W. A. A. El-Ghany in red-legged partridge chicks having mixed infection with C. meleagridis and C. baileyi (10). In ostriches, prolapsed cloacae, recta, and bursae were observed in dead 4-week-old chicks heavily infected with Cryptosporidium (8, 83, 84). Moreover, it has been proposed that Cryptosporidium infection is associated with pancreatic necrosis (80, 127). Infected 7-30-day- old ostrich chicks with Cryptosporidium genotype II showed sudden death with cloacal prolapse, and the oocysts were identified in the rectum, coprodeum, urodeum, and bursa (9). Pet birds like budgerigars (128), cockatiels (128, 129), parrots (130), and lovebirds (131) exhibited intestinal cryptosporidiosis with high mortality. When C. parvum or C. galli infects chickens or turkeys, no clinical signs could be detected (14, 43). However, in Dubai, an outbreak of catarrhal enteritis and mortality were reported among stone curlews (132). Birds infected with gastric C. galli showed diarrhea, weight loss, and sometimes mortality (46, 133, 39). Chronic proventriculitis is associated with C. galli with secondary infections (134, 135). In psittacine birds, strains of C. galli genotype III induced chronic vomiting, weight loss, and proventriculitis (58, 136). Other species, C. muris and C. andersoni, were found in birds’ droppings perhaps due to mechanical transmission from mammals (41). In China, adult ostriches showed infection with C. muris (137). In the Czech Republic, a novel genotype of Cryptosporidium (Eurasian woodcock) was molecularly identified, and it caused proventriculus and death of Eurasian woodcock species of birds (138). The life cycle of Cryptosporidium The shed oocysts are usually present in high numbers, resist the environmental conditions, and do not require special conditions for maturation. Infection with infective oocysts through ingestion is followed by excitation in the small intestine with the release of sporozoites. Released sporozoites proliferate in the intestinal epithelial cells where the asexual multiplication phase begins. As a result of asexual multiplication, invasion of merozoites to the neighboring cells is followed by the sexual multiplication phase. After this stage, production of macrogamonts and microgamonts occurs, followed by fertilization of macrogamonts and production of oocysts that sporulate in the host before shedding. The sporulated oocysts containing four sporozoites are shed in feces and respiratory secretions (especially in birds and children) in case of respiratory cryptosporidiosis (139, 140). Laboratory diagnosis Various methods including microscopic, immu- nological, and molecular techniques are used for the detection of Cryptosporidium infection (Figure 1). Microscopic examination includes concentra- tion flotation and sedimentation techniques. Fe- cal samples that were concentrated using Sheath- er’s sugar flotation technique followed by bright- field microscopy showed overall infections rates of Cryptosporidium of 3.4% in broilers and 10.6% in layer chickens in China (28). Iodine-saline wet mount method is another method for microscopic examination. However, routine fecal examination methods have some disadvantages like difficul- ties in distinguishing Cryptosporidium oocysts from other small debris particles, molds, algae, or yeasts (141). Ziehl-Neelsen staining of the fecal smears, bursae of Fabricius, or respiratory organs of broilers revealed infection rates of Cryptosporidium of 18.7% in Scotland (16), 24.3% in Greece (142), 37% in Morocco (143), and 4.5% in Tunisia (144). In acid-fast stained smears, Cryptosporidium oocysts appear as pink to red and spherical to ovoid bodies with a blue or purple background. This technique is useful in smears with a high number of oocysts or even a low number until one oocyst and can be stored permanently for a long time (145). For the detection of oocysts in smears, the sensitivity was 67.5% for modified acid-fast staining and 53.75% for Giemsa staining (146). In Japan, the histological examination of tissues detected 36.8% of Cryptosporidium in broilers and 33.3% in layers (147). However, in Iran, this rate was 23.8% in broilers (148). Flow cytometry is also used for the demonstra- tion of Cryptosporidium after staining with fluo- rescent markers (149). Cryptosporidium antigens can be detected through many immuno-chromatographic dipstick tests, enzyme immunoassays, reverse passive he- magglutination tests, and immunofluorescence Zbornik_1_2022_22.4.22.indd 14 22/04/2022 09:53:32 15Avian cryptosporidiosis: a significant parasitic disease of public health hazard techniques (150-152). Some Egyptian stud- ies used enzyme linked immunosorbent assay (ELISA) for the detection of antibodies against Cryptosporidium species in humans. For exam- ple, Gabr et al. (146) noted that the sensitivity of ELISA was 90% for the detection of cryptospo- ridiosis. In addition, Hassanein et al. (153) used this assay for the demonstration of C. parvum immunoglobulin G in the serum of Egyptian chil- dren with persistent diarrhea and acute lympho- blastic leukemia. Nanogold-beads-based ELISA was used for the detection of Cryptosporidium in the stool samples of diarrheic patients in Benha Province, Egypt. However, in an animal study, Fereig et al. (154) reported marked sero-preva- lence of C. parvum in cattle in South Egypt using ELISA. A similar study was recently conducted in Japan, where the indirect ELISA showed total sero-positivity of 96.3% for C. parvum in cattle (155). Unfortunately, the most common diagnostic traditional tools such as microscopy and immu- nology cannot discriminate Cryptosporidium spe- cies or subtypes to understand the transmission pathways and dynamics in humans (156). In ad- dition, these tools have a much lower sensitivity than polymerase chain reaction (PCR) (17, 18). Accordingly, genotyping and subtyping of Cryp- tosporidium were done using restriction fragment length polymorphism (RFLP) analysis of the 18S rRNA gene (157, 158) and Cryptosporidium oocyst wall protein (COWP) gene (159) and se- quence analysis of the 60-kDa glycoprotein gene (160). There are differences in the prevalence and infection rates according to the method used to detect Cryptosporidium (e.g., microscopic exami- nation vs. PCR) (161, 156). The first molecular report regarding the genotyping and subtyping of Cryptosporidium in calves in Kafr El Sheikh Province, Egypt, was made by Amer et al. (162). They sequenced the SSU rDNA gene and COWP gene of C. parvum as well as the high polymor- phic 60-kDa glycoprotein gene. In Beni-Suef Province, Egypt, Ibrahim et al. (163) identified C. parvum in cattle and buffaloes as well as C. hominis and C. parvum in humans using RFLP analysis of the COWP fragments. Moreover, the sequence analysis of the gp60 gene showed the C. parvum IIdA20G1 subtype in animals and hu- mans. Helmy et al. (18) demonstrated through molecular techniques that the prevalence rate of cryptosporidiosis among 165 diarrheal chil- dren in Ismailia Province was 49.1% (60.5% C. hominis and 38.3% C. parvum). Other molecular techniques such as fluorescence in situ hybrid- ization (FISH) and loop-mediated isothermal am- plification (LAMP), a nucleic acid amplification method, are used for the molecular detection of Cryptosporidium species (164, 165). Few studies were done on different avian species regarding the molecular characterization of Cryptosporidium (36, 43, 55, 28, 15, 24). In Algeria, the PCR analysis of the intestine showed prevalence rates of C. meleagridis of 34% (26/90) and 44% (25/57) in the intestines of chickens and turkeys, respectively (24). However, C. parvum DNA was detected in feces in 86% of the chickens in Brazil using PCR (15). In Germany, Helmy et al. (20) demonstrated that the PCR analysis of chickens and turkeys’ fecal specimens revealed an overall 7.0% prevalence rate of C. parvum, while in China, the prevalence was 10% in 90-day-old broiler chickens (25). Zoonotic importance Cryptosporidium species in humans are regarded as one of the most infectious zoonotic protozoan parasites since 1976 during an outbreak of cryptosporidiosis in the United States due to contamination of water (166). The different routes of cryptosporidiosis transmission to humans are listed in Table 2. Humans can be infected with cryptosporidiosis predominantly through the consumption of contaminated food or water with infective oocysts or through direct contact with infected animals (167-169). Amer et al. (19) found that the dominant genotypes IIa and IId of C. parvum in Egyptians which were similar to those in contact calves suggests calves can be potential reservoirs of zoonotic cryptosporidiosis. Some outbreaks have been reported among veterinary students as a result of contact with animals (168-171). Birds are considered an important source of infection as they are mechanical disseminators and shedders of oocysts for long distances in the environment (172, 54, 173, 93, 55, 174, 20). Moreover, infection of pigeon handlers with C. meleagridis in China has been reported (74). Workers in farms that handle with birds can contaminate water, feed, or litter in the poultry houses with Cryptosporidium oocysts of mammalian/human origin (37). Pet birds are also regarded as an important source of infection Zbornik_1_2022_22.4.22.indd 15 22/04/2022 09:53:32 16 W. A. A. El-Ghany to humans (87), but the literature related to this point is very rare. Traveling, living in villages, drinking underground water (lakes, etc.), and contact with animals are risk factors associated with human cryptosporidiosis (18, 175). Individuals can get infection of the gastroin- testinal tract through different Cryptosporidium species. Cryptosporidiosis can affect immuno- competent HIV-infected individuals, children, and healthy persons, causing asymptomatic carrier status or severe lethal diarrhea (176). Previously, C. parvum in ruminants was the only cause of human cryptosporidiosis for many years (177), while C. hominis was not recognized as a separate species till 2002 (178). Nowadays, both C. parvum and C. hominis cause more than 90% of human infection, while other species or genotypes of an- imal origin can cause sporadic infection. Mean- while, C. meleagridis is the only avian species with public health concern and causes zoonotic infec- tion of humans (179, 25, 26). Xiao (180) stated that C. meleagridis is the third most common spe- cies causing a serious public health hazard in hu- mans as it has a wider host spectrum. Two sub- types of C. meleagridis detected in AIDS patients were shared by chicken, ducks, and pigeons in the same location in Peru (25, 26). C. meleagridis was reported to be similar to C. parvum as both were responsible for 10%-20% of human crypto- sporidiosis (181-184). In Bangladesh, in urban regions, the prevalence rate of C. meleagridis was 13%, which was more than C. parvum with a prev- alence rate of 2% in children without diarrhea. However, in rural regions, the prevalence rates of C. meleagridis and C. parvum were 90% and 4%, respectively, causing subclinical cryptosporidio- sis (185). Stensvold et al. (186) and Wang et al. (26) demonstrated that the phylogenetic anal- ysis of multiple loci of C. meleagridis isolates showed that these isolates may be related to those in humans, and that constitutes evidence of human infection by C. meleagridis. Further- more, in Sweden, C. meleagridis isolates of layer and broiler chickens were found to be identical in nucleotide sequences (18S rRNA and HSP- 70 genes) to isolates of human origin (91). Per- haps, this may be due to the anthropozoonotic nature of cryptosporidiosis as it is transmitted from chickens kept in households to the person in contact (187). It is important to note that a reverse zoonotic transmission (zooanthropono- sis, from humans to animals) of C. parvum has also been reported (188). In addition, cryptospo- ridiosis is regarded as a largely anthroponotic disease that is transmitted from person to per- son, especially C. hominis or C. parvum (189). Cryptosporidiosis in humans is regarded as an acute life-threating disease especially in immu- nocompetent hosts (179). It is characterized by the sudden onset of clinical signs a week after infection in the form of prolonged and persis- tent diarrhea. Severe infection can be seen in very young, malnourished, and immunocom- promised persons. It has been documented that cryptosporidiosis is a major cause of mortality in infants and children under two years of age Figure 1: Methods of diagnosis of cryptosporidiosis Zbornik_1_2022_22.4.22.indd 16 22/04/2022 09:53:32 17Avian cryptosporidiosis: a significant parasitic disease of public health hazard Table 2: Transmission methods of cryptosporidiosis in humans in developing countries (190). Source of infection Reference (s) Food and water contamination [168, 169] Livestock animals [20, 167] Calves [19, 170, 171, 177] Domestic poultry (chickens and turkeys) [20, 25, 26, 37, 93, 172, 179, 187] Pigeons [70, 74] Geese [54] Captive pet birds [55, 87] Free range birds (mallard duck, graylag goose, common merganser, mute swan, grey heron, white stork, carrion crow, and rook) [93] Aquatic birds (ducks, geese, coots, and cormorants) [174] In Egypt, the prevalence rate of Cryptosporidium infection varies according to the locality. For example, Gabr et al. (191) demonstrated that Cryptosporidium infection was prevalent in diarrheic persons in Minia Province, as they showed that the overall prevalence rate of infection in 300 stained fecal samples was 44.7%. However, a previous study conducted by Gabr et al. (146) found that the prevalence rate was 61%. In immunocompetent and immunosuppressed children in Minia Province, the prevalence rates of Cryptosporidium infection were 42.2% and 60.2%, respectively (192). In another study conducted in Ismailia Province, the overall prevalence rate of Cryptosporidium species in humans was 49.1%, of which 60.5% were C. hominis, 38.2% were C. parvum, and 1.2% were C. parvum and C. bovis (193). In other provinces of Egypt, the prevalence rates were 23.5% in Abou El-Rish Hospital using nanogold-beads-based ELISA (194), 31.1% in Greater Cairo after staining of stool samples (195), 19.5% in Benha using microscopical and immunological techniques (196), 15% in Zagazig among chronic renal failure patients after conducting microscopical staining examination (197), and 33.3% in Ismailia among children (198). Moreover, ELISA results revealed that the incidences of Cryptosporidium were 37.7% and 91% in immunodeficient children and adult patients with cancer, respectively (199). In addition, the study of Antonios et al. (200) revealed that the prevalence rate of Cryptosporidium species among immunocompromised Egyptians was 33.3%. The differences in the infection rates may depend on the immune status of individuals, age of the host, environmental habitats, season, sample size, and the virulence of the parasite strain (201). Prevention and control Elimination of Cryptosporidium infection through the destruction of the parasite is difficult perhaps due to the resistant and persistent nature of the oocysts as well as the wide distribution of the infection (202). Household hygiene practices are recommended to prevent transmission of the different Cryptosporidium species causing infection with cryptosporidiosis (203). Hygienic measures include regular and thorough cleaning and disinfection of birds’ drinkers, feeders, cages, and premises, in addition to keeping separate cloths during contact with birds and washing hands with disinfectants before and after contact with the birds (67, 9, 135). A concentration of 6% or 7.5% hydrogen peroxide, chlorine dioxide, ozone, and ultraviolet light have been found to inactivate oocysts (204). Moreover, aluminum sulfate, iron sulfate, and iron chloride can coagulate oocysts present in water (205). In addition, reverse osmosis, filtration, and electronic/radiation methods have been used to counteract oocysts (206, 207). Halofuginone showed variable efficiency against cryptosporidiosis in animals (208, 23, 209). Lately, Hassan et al. (210) demonstrated the effect of silver nanoparticles as a water disinfectant against C. parvum, as oocysts showed considerable resistance to the traditional water treatment processes. Silver nanoparticles in a concentration of 1 ppm for 30 min and 0.1 ppm for 1 hr reduced oocysts by 97.2% and 94.4%, respectively. Until now, there is no specific treatment of cryptosporidiosis in animals and humans. How- ever, the United States Food and Drug Adminis- Zbornik_1_2022_22.4.22.indd 17 22/04/2022 09:53:32 18 W. A. A. El-Ghany tration (FDA) licensed and approved treatment of the infection with nitazoxanide after a trial con- ducted on mice (211). Nitazoxanide treated diar- rhea in buffaloes within three to four days and reduced the shedding of oocysts (212). In hu- mans, this treatment is recommended especially for patients aged one year or older in good health condition and with immune status (213, 214). Treatment with other drugs such as paromomy- cin, spiramycin, rifaximin, and azithromycin is unsatisfactory or inconsistent (215). Nutritional and supportive therapy is very important for com- plete recovery. Oral fluids and electrolyte replace- ment using sodium, potassium, bicarbonate, and glucose as well as starch-based oral rehydration solutions can provide calories with lower osmolar- ity, which can help in restoring mucosal function, enhance immune responses, and help rehabilitate the intestinal mucosal barrier following mucosal injury. Due to the development of drug resistance, there is a demand to search for alternatives to control cryptosporidiosis. Some studies were conducted to evaluate the effect of using different herbs and their extracts on controlling cryptosporidiosis (216). Oil extracts can be effective in the complete elimination of oocyst shedding on the ninth day postinfection (217). The anti-cryptosporidiosis effects of pine-bark, garlic, onion, cinnamon, blueberry, and curcumin extracts showed successful results (218-222, 212). In chickens, Wahba et al. (219) demonstrated that garlic extract induced a mild reduction in C. baileyi oocyst shedding in experimentally infected birds, but there was a significant difference with control non-treated birds. However, both garlic and nitazoxanide completely eradicated Cryptosporidium oocyst shedding in the treated buffaloes (212). Moreover, black seeds or black cumin (Nigella sativa) can be used for the treatment of C. parvum in experimentally infected calves (223). Zaki and El-Amir (224) stated that phenyl vinyl sulfone (cysteine protease inhibitor) with black seeds altered Cryptosporidium oocyst shedding compared with paromomycin treatment in mice. Another recent Egyptian study conducted by Sadek et al. (225) showed that both garlic and black seed extracts were greatly effective in reducing Cryptosporidium oocyst excretions in mice (75.4%) compared with treatment with nitazoxanide. Interestingly, after the treatment of cryptosporidiosis HIV patients with high doses of garlic, some patients showed recovery from chronic diarrhea and complete healing (226). In conclusion, cryptosporidiosis is considered an important disease in animals and birds as it induces severe economic loses, in addition to the public health significance of the disease in humans. Therefore, several studies, especially in developing countries, should be conducted on cryptosporidiosis infection in various hosts and its relation with humans. Conflict of interests No conflict of interests is declared. References 1. Ryan U. Cryptosporidium in birds, fish and amphibians. Exp Parasitol 2010; 124: 113–20. DOI: 10.1016/j.exppara.2009.02.002 2. Bodager JR, Parsons MB, Wright PC, et al. Complex epidemiology and zoonotic potential for Cryptosporidium suis in rural Madagascar. Vet Parasitol 2015; 207: 140–3. DOI: 10.1016/j.vet- par.2014.11.013 3. Ryan U, Power M. Cryptosporidium species in Australian wildlife and domestic animals. Par- asitology 2012; 139: 1673–88. DOI: 10.1017/ S0031182012001151 4. Bamaiyi PH, Umoh JU, Abdu PA, Lawal IA. The prevalence of Cryptosporidium oocysts in birds in Zaria, Nigeria. Borneo J Resour Sci Tech- nol 2013; 2: 52–9. 5. Inpankaew T, Jiyipong T, Wongpanit K, et al. Molecular detection of Cryptosporidium spp. infec- tions in water buffaloes from northeast Thailand. Trop Anim Health Prod 2014; 46: 487–90. DOI: 10.1007/s11250-013-0499-8 6. Hoerr FJ, Current WL, Haynes TB. Fatal cryptosporidiosis in quail. Avian Dis 1986; 30: 421–5. DOI: 10.2307/1590550 7. Ritter GD, Ley DH, Levy M, Guy J, Barnes HJ. Intestinal cryptosporidiosis and reovirus iso- lation from bobwhite quail (Colinus virginianus) with enteritis. Avian Dis 1986; 30: 603–8. DOI: 10.2307/1590430 8. Bezuidenhout AJ, Penrith ML, Burger WP. Prolapse of the phallus and cloaca in the ostrich (Struthio camelus). J S Afr Vet Assoc 1993; 64: 156–8. 9. Santos MMAB, Peiro´ JR, Meireles MV. Cryp- Zbornik_1_2022_22.4.22.indd 18 22/04/2022 09:53:32 19Avian cryptosporidiosis: a significant parasitic disease of public health hazard tosporidium infection in ostriches (Struthio came- lus) in Brazil: clinical, morphological and molecu- lar studies. Braz J Poult Sci 2005; 7: 113–7. DOI: 10.1590/S1516-635X2005000200008 10. Pages-Mante A, Pages-Bosch M, Majo-Mas- ferrer N, et al. An outbreak of disease associated with cryptosporidia on a red-legged partridge (Alectoris rufa) game farm. Avian Pathol 2007; 36: 275–8. DOI: 10.1080/03079450701439389 11. Nakamura AA, Meireles MV. Cryptosporid- ium infections in birds-a review. Braz J Vet Par- asitol 2015; 24: 253–67. DOI: 10.1590/s1984- 29612015063 12. McDougald LR. Cryptosporidiosis. In: Swayne DE, Glisson JR, McDougald LR, et al., eds. Diseases of poultry. 13th ed. Ames : Wiley-Black- well, 2013: 1085–91. 13. Berrilli F, D’Alfonso R, Giangaspero A, et al. Giardia duodenalis genotypes and Cryptospo- ridium species in humans and domestic animals in Côte d’Ivoire: occurrence and evidence for en- vironmental contamination. Trans R Soc Trop Med Hyg 2012; 106: 191–5. DOI: 10.1016/j. trstmh.2011.12.005 14. Ryan UM, Xiao L, Read C, et al. A rede- scription of Cryptosporidium galli Pavlasek, 1999 (Apicomplexa: Cryptosporidiidae) from birds. J Parasitol 2003a; 89: 809–13. DOI: 10.1645/ge- 74ri 15. Bomfim TCB, Gomes RS, Huber F, Couto MCM. The importance of poultry in en- vironmental dissemination of Cryptosporid- ium spp. Open Vet Sci J 2013; 7: 12–7. DOI: 10.2174/1874318801307010012 16. Randall CJ. Cryptosporidiosis of the bursa of fabricius and trachea in broil- ers. Avian Pathol 1982; 11: 95–102. DOI: 10.1080/03079458208436084 17. Helmy YA, Kruecken J, Noeckler K, von Samson-Himmelstjerna G, Zessin KH. Compari- son between two commercially available serolog- ical tests and polymerase chain reaction in the diagnosis of Cryptosporidium in animals and di- arrhoeic children. Parasitol Res 2014; 113: 211–6. DOI: 10.1007/s00436-013-3645-3 18. Helmy YA, von Samson-Himmelstjerna G, Noeckler K, Zessin KH. Frequencies and spa- tial distributions of Cryptosporidium in livestock animals and children in the Ismailia province of Egypt. Epidemiol Infect 2015; 143: 1208–18. DOI: 10.1017/s0950268814001824 19. Amer S, Zidan S, Adamu H, Ye J, Roellig D, et al. Prevalence and characterization of Cryp- tosporidium spp. in dairy cattle in Nile River delta provinces, Egypt. Exp Parasitol 2013; 135: 518– 23. DOI: 10.1016/j.exppara.2013.09.002 20. Helmy YA, Krücken J, Abdelwhab EM, von Samson-Himmelstjerna G, Hafez HM. Molecular diagnosis and characterization of Cryptosporid- ium spp. in turkeys and chickens in Germany reveals evidence for previously undetected para- site species. PLoS One 2017; 12: e0177150. DOI: 10.1371/journal.pone.0177150 21. Tyzzer EE. Coccidiosis in gallinaceous birds. Am J Hyg 1929; 10: 269–83. DOI: 10.1093/ oxfordjournals.aje.a112759 22. Slavin D. Cryptosporidium meleagridis (sp. nov.). J Comp Pathol 1955; 65: 262–6. doi: 10.1016/S0368-1742(55)80025-2 23. Sreter T, Kovacs G, da Silva AJ, et al. Mor- phologic host specificity and molecular charac- terization of a Hungarian Cryptosporidium melea- gridis isolate. Appl Environ Microbiol 2000; 66: 735–8. DOI: 10.1128%2Faem.66.2.735-738.2000 24. Baroudi D, Khelef D, Goucem R, et al. Com- mon occurrence of zoonotic pathogen Cryptospo- ridium meleagridis in broiler chickens and turkeys in Algeria. Vet Parasitol 2013; 196: 334–40. DOI: 10.1016/j.vetpar.2013.02.022 25. Wang L, Xue X, Li J, et al. Cryptosporid- iosis in broiler chickens in Zhejiang province, China: molecular characterization of oocysts de- tected in fecal samples. Parasite 2014a; 21: e36. DOI: 10.1051/parasite/2014035 26. Wang Y, Yang W, Cama V, et al. Population genetics of Cryptosporidium meleagridis in hu- mans and birds: evidence for cross-species trans- mission. Int J Parasitol 2014b; 44: 515–21. DOI: 10.1016/j.ijpara.2014.03.003 27. Liao C, Wang T, Koehler AV, et al. Molecular investigation of Cryptosporidium in farmed chick- ens in Hubei province, China, identifies ‘zoonotic’ subtypes of C. meleagridis, Parasit Vectors 2018; 11: e484. DOI: 10.1186/s13071-018-3056-5 28. Wang R, Jian F, Sun Y, et al. Large-s- cale survey of Cryptosporidium spp. in chick- ens and Pekin ducks (Anas platyrhynchos) in Henan, China: prevalence and molecular charac- terization. Avian Pathol 2010; 39: 447–51. DOI: 10.1080/03079457.2010.518314 29. Laatamna AE, Holubova N, Sak B, Kvac M. Cryptosporidium meleagridis and C. baileyi (Api- complexa) in domestic and wild birds in Algeria. Folia Parasitol 2017; 64: e018. DOI: 10.14411/ Zbornik_1_2022_22.4.22.indd 19 22/04/2022 09:53:32 20 W. A. A. El-Ghany fp.2017.018 30. Current WL, Upton SJ, Haynes TB. The life cycle of Cryptosporidium baileyi n. sp. (Apicompl- exa Cryptosporidiidae) infecting chickens. J Pro- tozool 1986; 33: 289–96. DOI: 10.1111/j.1550- 7408.1986.tb05608.x 31. Blagburn BL, Lindsay DS, Hoerr FJ, Davis JF, Giambrone JJ. Pathobiology of cryptosporid- iosis (C. baileyi) in broiler chickens. J Protozool 1991; 38: 25S–8S. 32. Goodwin MA, Brown J, Resurreccion RS, Smith JA. Respiratory coccidiosis (Cryptosporid- ium baileyi) among northern Georgia broilers in one company. Avian Dis 1996; 40: 572–5. DOI: 10.2307/1592266 33. Chvala S, Fragner K, Hackl R, Hess M, Weissenbock H. Cryptosporidium infection in do- mestic geese (Anser anser f. domestica) detected by in-situ hybridization. J Comp Pathol 2006; 134: 211–8. DOI: 10.1016/j.jcpa.2005.11.002 34. Abbassi H, Coudert F, Cherel Y, et al. Re- nal cryptosporidiosis (Cryptosporidium baileyi) in specific-pathogen-free chickens experimentally coinfected with Marek’s disease virus. Avian Dis 1999; 43: 738–44. DOI: 10.2307/1592742 35. Trampel DW, Pepper TM, Blagburn BL. Urinary tract cryptosporidiosis in commercial laying hens. Avian Dis 2000; 44: 479–84. DOI: 10.2307/1592566 36. Huber F, da Silva S, Bomfim TC, Teixeira KR, Bello AR. Genotypic characterization and phylogenetic analysis of Cryptosporidium sp. from domestic animals in Brazil. Vet Parasitol 2007; 150: 65–74. DOI: 10.1016/j.vetpar.2007.08.018 37. Kabir MHB, Han Y, Lee S-H, et al. Prev- alence and molecular characterization of Cryp- tosporidium species in poultry in Bangladesh. One Health 2020; 9: 100122. DOI: 10.1016/j. onehlt.2020.100122 38. O’Donoghue PJ. Cryptosporidium and cryptosporidiosis in man and animals. Int J Par- asitol 1995; 25: 139–95. doi: 10.1016/0020- 7519(94)e0059-v 39. Morgan UM, Monis PT, Xiao L, et al. Molecular and phylogenetic characterisation of Cryptosporidium from birds. Int J Parasi- tol 2001; 31: 289–96. doi: 10.1016/s0020- 7519(00)00164-8 40. Ramirez NE, Ward LA, Sreevatsan S. A review of the biology and epidemiology of cryp- tosporidiosis in humans and animals. Microbes Infect 2004; 6: 773–85. DOI: 10.1016/j.mic- inf.2004.02.021 41. Ng J, Pavlasek I, Ryan U. Identification of novel Cryptosporidium genotypes from avian hosts. Appl Environ Microbiol 2006; 72: 7548–53. DOI: 10.1128/AEM.01352-06 42. Santana BN, Kurahara B, Nakamura AA, et al. Detection and characterization of Cryptosporid- ium species and genotypes in three chicken pro- duction systems in Brazil using different molecu- lar diagnosis protocols. Prev Vet Med 2018; 151: 73–8. DOI: 10.1016/j.prevetmed.2018.01.007 43. McEvoy JM, Giddings CW. Cryptosporid- ium in commercially produced turkeys on-farm and postslaughter. Lett Appl Microbiol 2009; 48: 302–6. DOI: 10.1111/j.1472-765X.2008.02516.x 44. Levine ND. Protozoan parasites of domestic animals and of man. Minneapolis: Burgess Pub- lishing, 1961: 412. 45. Proctor SJ, Kemp RL. Cryptosporidium anserinum sp. n. (Sporozoa) in a domestic goose Anser anser L, from Iowa. J Protozool 1974; 21: 664–6. DOI: 10.1111/j.1550- 46. Blagburn BL, Lindsay DS, Hoerr FJ, Atlas AL, Toivio-Kinnucan M. Cryptosporidium sp. in- fection in the proventriculus of an Australian di- amond firetail finch (Staganoplura bella: Passeri- formes, Estrildidae). Avian Dis 1990; 34: 1027–30. DOI: 10.2307/1591401 47. Pavlasek I. Cryptosporidia: biology diag- nosis, host spectrum specificity and the environ- ment. Klin Mikrobiol Infekc Lek1999; 3: 290–301. 48. Pavlasek I. Findings of cryptosporidia in the stomach of chickens and of exotic and wild birds. Veterinarstvi 2001; 51: 103–8. 49. Shaapan RM, Khalil FAM, Abou El Ezz MT. Cryptosporidiosis and toxoplasmosis in native quails of Egypt. Res J Vet Sci 2011; 4: 30–6. DOI: 10.3923/rjvs.2011.30.36 50. Nagwa EA, El-Akabawy LM, El-Madawy RS, Toulan EI. Studies on intestinal protozoa of poultry in Gharbia governorate. Benha Vet Med J 2013; 25: 78–83. 51. Kalifa MM, Nassar AM, Nisreen EM, Ab- del-Wahab AM. Cryptosporidium species in ducks: parasitological, serological and molecular studies in Egypt. Int J Adv Res Biol Sci 2016; 3: 23–31. 52. Abe N, Makino I. Multilocus genotypic analysis of Cryptosporidium isolates from cock- atiels, Japan. Parasitol Res 2010; 106: 1491–7. DOI: 10.1007/s00436-010- 53. Jellison KL, Distel DL, Hemond HF, Schauer DB. Phylogenetic analysis of the hypervariable Zbornik_1_2022_22.4.22.indd 20 22/04/2022 09:53:32 21Avian cryptosporidiosis: a significant parasitic disease of public health hazard region of the 18S rRNA gene of Cryptosporidium oocysts in feces of Canada geese (Branta canaden- sis): evidence for five novel genotypes. Appl En- viron Microbiol 2004; 70: 452–8. DOI: 10.1128/ AEM.70.1.452-458.2004 54. Zhou L, Kassa H, Tischler ML, Xiao L. Host-adapted Cryptosporidium spp. in Canada geese (Branta canadensis). Appl Environ Microbiol 2004; 70: 4211–5. DOI: 10.1128/AEM.70.7.4211- 4215.2004 55. Nakamura AA, Simoes DC, Antunes RG, da Silva DC, Meireles MV. Molecular characterization of Cryptosporidium spp. from fecal samples of birds kept in captivity in Brazil Vet Parasitol 2009; 166: 47–51. DOI: 10.1016/j.vetpar.2009.07.033 56. Meireles MV, Soares RM, Santos MM, Gen- nari SM. Biological studies and molecular character- ization of a Cryptosporidium isolate from ostriches (Struthio camelus). J Parasitol 2006; 92: 623–6. DOI: 10.1645/0022-395(2006)92[623:BSAM- CO]2.0.CO;2. 57. Nguyen ST, Fukuda Y, Tada C, et al. Prev- alence and molecular characterization of Cryp- tosporidium in ostriches (Struthio camelus) on a farm in central Vietnam. Exp Parasitol 2013; 133: 8–11. DOI: 10.1016/j.exppara.2012.10.010 58. Makino I, Abe N, Reavill DR. Cryptospo- ridium avian genotype III as a possible causative agent of chronic vomiting in peach-faced lovebirds (Agapornis roseicollis). Avian Dis 2010; 54: 1102– 7. DOI: 10.1637/9227-123009-case.1 59. Qi M, Wang R, Ning C, et al. Cryptospo- ridium spp. in pet birds: genetic diversity and potential public health significance. Exp Para- sitol 2011; 128: 336–40. DOI: 10.1016/j.exp- para.2011.04.003 60. Sevá AP, Funada MR, Richtzenhain L, et al. Genotyping of Cryptosporidium spp. from free-liv- ing wild birds from Brazil. Vet Parasitol 2011; 175: 27–32. DOI: 10.1016/j.vetpar.2010.09.031 61. Gomes RS, Huber F, da Silva S, do Bomfim TC. Cryptosporidium spp. parasitize exotic birds that are commercialized in markets, commercial aviaries, and pet shops. Parasitol Res 2012; 110: 1363–70. DOI: 10.1007/s00436-011-2636-5 62. Nakamura AA, Homem CG, Silva AMJ, Meireles MV. Diagnosis of gastric cryptosporidi- osis in birds using a duplex real-time PCR assay. Vet Parasitol 2014; 205: 7–13. DOI: 10.1016/j. vetpar.2014.07.033 63. Kik MJL, van Asten AJAM, Lenstra JA, Kirpensteijn J. Cloaca prolapse and cystitis in green iguana (Iguana iguana) caused by a novel Cryptosporidium species. Vet Parasitol 2011; 175: 165–7. DOI: 10.1016/j.vetpar.2010.10.002 64. Xiao L, Fayer R, Ryan U, Upton SJ. Crypto- sporidium taxonomy: recent advances and impli- cations for public health. Clin Microbiol Rev 2004; 17: 72–97. DOI: 10.1128/cmr.17.1.72-97.2004 65. Tarwid JN, Cawthorn RJ, Riddell C. Cryp- tosporidiosis in the respiratory tract of turkeys in Saskatchewan. Avian Dis 1985; 29(2): 528–32. DOI: 10.2307/1590516 66. Lindsay DS, Blagburn BL, Sundermann CA. Host specificity of Cryptosporidium sp. iso- lated from chickens. J Parasitol 1986; 72(4): 565– 8. DOI: 10.2307/3281511 67. Sreter T, Varga I. Cryptosporidiosis in birds: a review. Vet Parasitol 2000; 87(4): 261–79. DOI: 10.1016/s0304-4017(99)00178-8 68. Richter D, Wiegand-Tripp G, Burk- hardt E, Kaleta EF. Natural infections by Cryp- tosporidium sp. in farm-raised ducks and geese. Avian Pathol 1994; 23(2): 277–86. DOI: 10.1080/03079459408418995 69. Lindsay DS, Blagburn BL, Sundermann CA, Hoerr FJ. Experimental infections in domes- tic ducks with Cryptosporidium baileyi isolated from chickens. Avian Dis 1989; 33: 69–73. DOI: 10.2307/1591069 70. Ozkul IA, Aydin Y. Small-intestinal crypto- sporidiosis in a young pigeon. Avian Pathol 1994; 23: 369–72. DOI: 10.1080/03079459408419006 71. Rodriguez F, Oros J, Rodriguez JL, et al. Intestinal cryptosporidiosis in pigeons (Col- umba livia). Avian Dis 1997; 41: 748–50. DOI: 10.2307/1592171 72. Radfar MH, Asl EN, Seghinsara HR, De- haghi MM, Fathi S. Biodiversity and prevalence of parasites of domestic pigeons (Columba livia domestica) in a selected semiarid zone of South Khorasan, Iran. Trop Anim Health Prod 2012; 44: 225–9. DOI: 10.1007/s11250-011-0002-3 73. Koompapong K, Mori H, Thammasonthijar- ern N, et al. Molecular identification of Cryptospo- ridium spp. in seagulls, pigeons, dogs, and cats in Thailand. Parasite 2014; 21: 52. DOI: 10.1051/ parasite/2014053 74. Li J, Lin X, Zhang L, et al. Molecular char- acterization of Cryptosporidium spp. in domestic pigeons (Columba livia domestica) in Guangdong province, southern China. Parasitol Res 2015; 114: 2237–41. DOI: 10.1007/s00436-015-4415-1 75. Oliveira BCM, Ferrari ED, da Cruz Pane- Zbornik_1_2022_22.4.22.indd 21 22/04/2022 09:53:33 22 W. A. A. El-Ghany gossi MF, et al. First description of Cryptosporid- ium parvum in carrier pigeons (Columba livia). Vet Parasitol 2017; 243: 148–50. DOI: 10.1016/j.vet- par.2017.06.023\ 76. Tham VL, Kniesberg S, Dixon BR. Crypto- sporidiosis in quails. Avian Pathol 1982; 11: 619– 26. DOI: 10.1080/03079458208436138 77. Murakami S, Miyama M, Ogawa A, Shimada J, Nakane T. Occurrence of conjunctivitis, sinus- itis and upper region tracheitis in Japanese quail (Coturnix coturnix japonica), possibly caused by Mycoplasma gallisepticum accompanied by Cryp- tosporidium sp. infection. Avian Pathol 2002; 31: 363–70. DOI: 10.1080/030794502201633 78. Wang R, Wang F, Zhao J, et al. Cryptospo- ridium spp. in quails (Coturnix coturnix japonica) in Henan, China: molecular characterization and public health significance. Vet Parasitol 2012; 187: 534–7. DOI: 10.1080/03079457.2010.518314 79. Cardozo SV, Teixeira Filho WL, Lopes CW. Experimental transmission of Cryptosporidium baileyi (Apicomplexa: Cryptosporidiidae) isolated of broiler chicken to Japanese quail (Coturnix ja- ponica)). Rev Bras Parasitol Vet 2005; 14: 119–24. 80. Allwright DM, Wessels J. Cryptosporidium species in ostriches. Vet Rec 1993; 133: 24. DOI: 10.1136/vr.133.1.24-a 81. Gajadhar AA. Cryptosporidium species in imported ostriches and consideration of possible implications for birds in Canada. Can Vet J 1993; 34: 115–6. 82. Gajadhar AA. Host specificity studies and oocyst description of a Cryptosporidium sp. iso- lated from ostriches. Parasitol Res 1994; 80: 316– 9. DOI: 10.1007/BF02351873 83. Penrith ML, Burger WP. A Cryptosporidium sp in an ostrich. J S Afr Vet Assoc 1993; 64: 60–1. 84. Penrith ML, Bezuidenhout AJ, Burger WP, Putterill JF. Evidence for cryptosporidial infection as a cause of prolapse of the phallus and cloaca in ostrich chicks (Struthio camelus). Onderstepoort J Vet Res 1994; 6: 283–9. 85. Ponce Gordo F, Herrera S, Castro AT, García Duran B, Martínez Días RA. Parasites from farmed ostriches (Struthio camelus) and rheas (Rhea americana) in Europe. Vet Parasi- tol 2002; 107: 137–60. DOI: 10.1016/s0304- 4017(02)00104-8. 86. Oliveira FCR, Ederli NB, Ederli BB, Al- buquerque MC, Santos MD. Occurrence of Crypto- sporidium spp. oocysts (Apicomplexa, Cryptospo- ridiidae) in ostriches, Struthio camelus L., 1758 (Aves, Struthionidae) reared in North and Lowered Coastline regions of the state of Rio de Janeiro, Brazil. Rev Bras Parasitol Vet 2008; 17: 322–5. 87. Sivajothi S, Sudhakara Reddy B. Crypto- sporidiosis in pet birds-zoonotic alert to kids. Int J Avian Wildlife Biol 2018; 3: 45–6. DOI: 10.15406/ ijawb.2018.03.00051 88. van Zeeland YR, Schoemaker NJ, Kik MJ, van der Giessend JW. Upper respiratory tract infection caused by Cryptosporidium baileyi in three mixed-bred falcons (Falco rusticolus x Falco cherrug). Avian Dis 2008; 52: 357–63. DOI: 10.1637/8121-100207-Case.1 89. Molina-Lopez RA, Ramis A, Martin-Vazquez S, et al. Cryptosporidium baileyi infection associ- ated with an outbreak of ocular and respiratory disease in otus owls (Otus scops) in a rehabilita- tion centre. Avian Pathol 2010; 39: 171–6. DOI: 10.1080/03079451003717589 90. Chelladurai JJ, Clark ME, Kváè M, et al. Cryptosporidium galli and novel Cryptosporidium avian genotype VI in North American red-winged black birds (Agelaius phoeniceus). Parasitol Res 2016; 115: 1901–6. DOI: 10.1007/s00436-016- 4930-8 91. Silverlas C, Mattsson JG, Insulander M, Lebbad M. Zoonotic transmission of Cryptospo- ridium meleagridis on an organic Swedish farm. Int J Parasitol 2012; 42: 963–7. DOI: 10.1016/j. ijpara.2012.08.008 92. Samad MA. Public health threat caused by zoonotic diseases in Bangladesh, Bangl J Vet Med 2011; 9: 95–120. DOI: 10.3329/bjvm. v9i2.13451 93. Majewska AC, Graczyk TK, Slodko- wicz-Kowalska A, et al. The role of free-ranging, captive, and domestic birds of western Poland in environmental contamination with Cryptosporid- ium parvum oocysts and Giardia lamblia cysts. Parasitol Res 2009; 104: 1093–9. DOI: 10.1007/ s00436-008-1293-9 94. Quah JX, Ambu S, Lim YA, Mahdy MA, Mak JW. Molecular identification of Cryptosporid- ium parvum from avian hosts. Parasitology 2011; 138: 533–7. DOI: 10.1017/s0031182010001691 95. Goodwin MA, Steffens WL, Russell ID, Brown J. Diarrhea associated with intestinal cryptosporidiosis in turkeys. Avian Dis 1988; 32: 63–7. 10.2307/1590949 96. Gharagozlou MJ, Dezfoulian O, Rahbari S, et al. Intestinal cryptosporidiosis in turkeys in Iran. J Vet Med A Physiol Pathol Clin Med 2006; 53: Zbornik_1_2022_22.4.22.indd 22 22/04/2022 09:53:33 23Avian cryptosporidiosis: a significant parasitic disease of public health hazard 282–5. DOI: 10.1111/j.1439-0442.2006.00843.x 97. Bermudez AJ, Ley DH, Levy MG, et al. In- testinal and bursal cryptosporidiosis in turkeys following inoculation with Cryptosporidium sp. isolated from commercial poults. Avian Dis 1988; 32: 445–50. DOI: 10.2307/1590910 98. Woodmansee DB, Pavlásek I, Pohlenz JFL, Moon HW. Subclinical cryptosporidiosis of tur- keys in Iowa. J Parasitol 1988; 74: 898–900. DOI: 10.2307/3282279 99. Fayer R, Speer CA, Dubey JP. The general biology of Cryptosporidium. In: Fayer R, Xiao L, eds. Cryptosporidium and cryptosporidiosis. New York : CRC Press, 1997. 100. Glisson JR, Brown TP, Brugh M, Page RK, Kleven SH, Daviset RB. Sinusitis in turkeys as- sociated with respiratory cryptosporidiosis. Avian Dis 1984; 28(3): 783-90. 101. Mason RW. Conjunctival cryptosporidio- sis in a duck. Avian Dis 1986; 30: 598–600. 102. O’Donoghue PJ, Tham VL, de Saram WG, Paull KL, McDermott S. Cryptosporidium infections in birds and mammals and attempted cross-transmission studies. Vet Parasitol 1987; 26: 1–11. DOI: 10.1016/0304-4017(87)90071-9 103. Randall CJ. Conjunctivitis in pheasants associated with cryptosporidial infection. Vet Rec 1986; 118: 211. DOI: 10.1136/vr.118.8.211 104. Mason RW, Hartley WJ. Respiratory cryp- tosporidiosis in a peacock chick. Avian Dis 24(3): 1980; 771–6. 105. Coldwell L, Caldow G, Holliman A, et al. Cryptospordium baileyi in wild red grouse with ‘bulgy eye’. Vet Rec 2012; 170: 603–4. DOI: 10.1136/vr.e3940 106. Ley DH, Moresco A, Frasca S Jr. Con- junctivitis, rhinitis, and sinusitis in cliff swallows (Petrochelidon pyrrhonota) found in association with Mycoplasma sturni infection and cryptospo- ridiosis. Avian Pathol 2012; 41: 395–401. DOI: 10.1080/03079457.2012.697624 107. Bougiouklis PA, Weissenböck H, Wells A, et al. Otitis media associated with Cryptospo- ridium baileyi in a Saker falcon (Falco cherrug). J Comp Pathol 2013; 148: 419–23. DOI: 10.1016/j. jcpa.2012.09.005 108. Baines D, Newborn D, Richardson M. Spread of Cryptosporidium baileyi in red grouse Lagopus lagopus scoticus. Vet Rec 2014; 175: 149. DOI: 10.1136/vr.102275 109. Goodwin MA. Cryptosporidiosis in birds: a review. Avian Pathol 1989; 18: 365–84. DOI: 10.1080/03079458908418612 110. Blagburn BL, Lindsay DS, Giambrone JJ, Sundermann CA, Hoerr FJ. Experimental crypto- sporidiosis in broiler chickens. Poultry Sci 1987; 66: 442–9. DOI: 10.3382/ps.0660442 111. Meireles MV, Paulillo AC, Silva GS, et al. Experimental infection with Cryptosporidium bai- leyi in broilers raised on floor-pens. Braz J Poult Sci 1999; 1: 37–42. 112. Abbassi H, Coudert F, Dambrine G, Chérel Y, Naciri M. Effect of Cryptosporidium bai- leyi in specific pathogen free chickens vaccinated (CVI988/ Rispens) and challenged with HPRS-16 strain of Marek’s. Avian Pathol 2000; 29: 623–34. DOI: 10.1080/03079450020016887 113. Hornok S, Heijmans JF, Békési L, et al. Interaction of chicken anaemia virus and Crypto- sporidium baileyi in experimentally infected chick- ens. Vet Parasitol 1998; 76: 43–55. DOI: 10.1016/ s0304-4017(97)00046-0 114. Levy MG, Ley DH, Barnes HJ, Gerig TM, Corbett WT. Experimental cryptosporidiosis and infectious bursal disease virus infection of spe- cific pathogen-free chickens. Avian Dis 1988; 32: 803–11. DOI: 10.2307/1591002 115. Guy JS, Levy MG, Ley DH, Barnes HJ, Gerig TM. Interaction of reovirus and Crypto- sporidium baileyi in experimentally infected chickens. Avian Dis 1988; 32: 381–90. DOI: 10.2307/1590901 116. Scott TR. Our current understanding of humoral immunity of poultry. Poult Sci 2004; 83: 574–9. DOI: https://DOI.org/10.1093/ps/83.4.574 117. Naciri M, Mazzella O, Coudert F. Interac- tions cryptosporidies-virus sauvage ou vaccinal de la maladie de Marek chez le poulet. Rec Méd Vét 1989; 165: 383–7. 118. Rhee JK, Kim HC, Lee SB, Yook SY. Im- munosuppressive effect of Cryptosporidium bai- leyi infection on vaccination against Newcastle disease in chicks. Korean J Parasitol 1998a; 36: 121–5. DOI: 10.3347/kjp.1998.36.2.121 119. Eladl AH, Hamed HR, Khalil MR. Con- sequence of Cryptosporidiosis on the immune response of vaccinated broiler chickens against Newcastle disease and/or avian influenza. Vet Res Commun 2014; 38: 237–47. DOI: 10.1007/ s11259-014-9610-5 120. Rhee JK, Yang HJ, Yook SY, Kim HC. Im- munosuppressive effect of Cryptosporidium baileyi infection on vaccination against avian infectious bronchitis in chicks. Korean J Parasitol 1998b; Zbornik_1_2022_22.4.22.indd 23 22/04/2022 09:53:33 24 W. A. A. El-Ghany 36: 203–6. DOI: 10.3347/kjp.1998.36.3.203 121. Hao YX, Yang JM, He C, Liu Q, McAllis- ter TA. Reduced serologic response to avian influ- enza vaccine in specific-pathogen-free chicks in- oculated with Cryptosporidium baileyi. Avian Dis 2008; 52: 690–3. DOI: 10.1637/8370-052608- reg.1 122. Goodwin MA, Brown J. Intestinal crypto- sporidiosis in chickens. Avian Dis 1989; 33: 770– 7. DOI: 10.2307/1591159 123. Meireles MV, Paulillo AC, Silva GS, et al. Influência da infecção experimental com Crypto- sporidium baileyi na resposta imune de frangos de corte vacinados contra a doença de Newcastle. Rev Bras Cienc Vet 1998; 5: 15–9. DOI: 10.4322/ rbcv.2015.092 124. Ranck FM Jr, Hoerr FJ. Cryptosporidia in the respiratory tract of turkeys. Avian Dis 1987; 31: 389–91. DOI: 10.2307/1590893 125. Ryan UM, Xiao L. Birds. In: Fayer R, Xiao L, eds. Cryptosporidium and cryptosporidiosis. Boca Raton : CRC Press, 2008. 126. Guy JS, Levy MG, Ley DH, Barnes HJ. Ex- perimental reproduction of enteritis in bobwhite quail (Colinus virginianus) with Cryptosporidium and reovirus. Avian Dis 1987; 31: 713–22. DOI: 10.2307/1591021 127. Jardine JE, Verwoerd DJ. Pancreatic cryptosporidiosis in ostriches. Avian Pathol 1997; 26: 665–70. DOI: 10.1080/03079459708419243 128. Goodwin MA, Krabill VA. Diarrhea asso- ciated with small-intestinal cryptosporidiosis in a budgerigar and in a cockatiel. Avian Dis 1989; 33: 829–33. DOI: 10.2307/1591170 129. Lindsay DS, Blagburn BL, Hoerr FJ. Small intestinal cryptosporidiosis in cocka- tiels associated with Cryptosporidium baileyi- like oocysts. Avian Dis 1990; 34: 791–3. DOI: 10.2307/1591283 130. Morgan UM, Xiao L, Limor J, et al. Cryp- tosporidium meleagridis in an Indian ring-necked parrot (Psittacula krameri). Aust Vet J 2000; 78: 182–3. DOI: 10.1111/j.1751-0813.2000. tb10589.x 131. Belton DJ, Powell IB. Cryptosporidiosis in lovebirds (Agapornis sp.). N Z Vet J 1987; 35: 15. DOI: 10.1080/00480169.1987.35364 132. Zylan K, Bailey T, Smith HV, et al. An outbreak of cryptosporidiosis in a collec- tion of Stone curlews (Burhinus oedicnemus) in Dubai. Avian Pathol 2008; 37: 521–6. DOI: 10.1080/03079450802357019 133. Clubb S. What is your diagnosis? J Avian Med Surg 1997; 11: 41–2. 134. Antunes RG, Simões DC, Nakamura AA, Meireles MV. Natural infection with Cryptospo- ridium galli in canaries (Serinus canaria), in a cockatiel (Nymphicus hollandicus), and in lesser seed-finches (Oryzoborus angolensis) from Brazil. Avian Dis 2008; 52: 702–5. DOI: 10.1637/8356- 051208-case.1 135. Silva DC, Homem CG, Nakamura AA, et al. Physical, epidemiological, and molecular eval- uation of infection by Cryptosporidium galli in Passeriformes. Parasitol Res 2010; 107: 271–7. DOI: 10.1007/s00436-010-1858-2. 136. Ravich ML, Reavill DR, Hess L, Chil- dress AL, Wellehan JFX Jr. Gastrointestinal cryptosporidiosis in captive psittacine birds in the United States: a case review. J Avian Med Surg 2014; 28: 297–303. DOI: 10.1647/1082- 6742-28.4.297 137. Qi M, Huang L, Wang R, et al. Natural infection of Cryptosporidium muris in ostriches (Struthio camelus). Vet Parasitol 2014; 205: 518– 22. DOI: 10.1016/j.vetpar.2014.06.035 138. Ryan U, Xiao L, Read C, et al. Identifica- tion of novel Cryptosporidium genotypes from the Czech Republic. Appl Environ Microbiol 2003b; 69: 4302–7. DOI: 10.1128/AEM.69.7.4302- 4307.2003. 139. Dhillon AS, Thacker HL, Dietzel AV, Winterfield RW. Respiratory cryptosporidiosis in broiler chickens. Avian Dis 1981; 25: 747–51. 140. Sponseller JK, Griffiths JK, Tzipori S. The evolution of respiratory cryptosporidiosis: evidence for transmission by inhalation. Clin Microbiol Rev 2014; 27: 575–86. DOI: 10.1128/ CMR.00115-13. 141. Fayer R, Morgan U, Upton SJ. Epidemiol- ogy of Cryptosporidium: transmission, detection and identification. Int J Parasitol 2000; 30: 1305– 22. DOI: 10.1016/s0020-7519(00)00135-1. 142. Papadopoulou C, Xylouri E, Zisides N. Cryptosporidial infection in broiler chick- ens in Greece. Avian Dis 1988; 32: 842–3. DOI: 10.2307/1591010 143. Kichou F, Saghir F, El Hamidi M. Natural Cryptosporidium sp. infection in broiler chickens in Morocco. Avian Pathol 1996; 25: 103–11. DOI: 10.1080/03079459608419124 144. Soltane R, Guyot K, Dei-Cas E, Ayadi A. Prevalence of Cryptosporidium spp. (Eucoccidior- ida: Cryptosporiidae) in seven species of farm an- Zbornik_1_2022_22.4.22.indd 24 22/04/2022 09:53:33 25Avian cryptosporidiosis: a significant parasitic disease of public health hazard imals in Tunisia. Parasite 2007; 14: 335–8. DOI: 10.1051/parasite/2007144335 145. Sevinc F, Irmak K, Sevinc M. The preva- lence of Cryptosporidium parvum infection in the diarrhoiec and non- diarrheic calves. Revue Méd Vét 2003; 154: 357–61. 146. Gabr NS, Abdellatif MZM, ElHafeez EHA, Rabou RAM. Comparison between Elisa and var- ious stains techniques in laboratory diagnosis of cryptosporidiosis. J Egypt Soc Parasitol 2014; 44: 509–16. DOI: 10.12816/jesp.2014.90410 147. Itakura C, Goryo M, Umemura T. Crypto- sporidial infection in chickens. Avian Pathol 1984; 13: 487–99. DOI: 10.1080/03079458408418550 148. Shemshadi B, Bahadori SR, Mozafari A. Study on cryptosporidiosis incidence in broilers in Garmsar region, Iran. Comp Clin Pathol 2011; 20: 143–9. DOI: 10.1007/s00580-010-0970-0 149. Sonzogni-Desautels K, Di Lenardo TZ, Renteria AE, et al. A protocol to count Crypto- sporidium oocysts by flow cytometry without an- tibody staining. PLoS Negl Trop Dis 2019; 13(3): e0007259. DOI: 10.1371/journal.pntd.0007259. 150. Farrington M, Winters S, Walker C, Miller R, Rubenstein D. Cryptosporidium antigen detec- tion in human feces by reverse passive hemagglu- tination assay. J Clin Microbiol 1994; 32: 2755– 9. DOI: 10.1128/jcm.32.11.2755-2759.1994 151. Ndao M. Diagnosis of parasitic diseases: old and new approaches. Interdiscip Perspect Infect Dis 2009; 2009: e278246. DOI: 10.1155/2009/278246 152. Fereig RM, Abdelbaky HH, Ihara F, Nishi- kawa Y. Development and evaluation of the first immunochromatographic test that can detect spe- cific antibodies against Cryptosporidium parvum. Acta Trop 2018; 185: 349–56. DOI: 10.1016/j.ac- tatropica.2018.06.019 153. Hassanein SM, Abd-El-Latif MM, Has- sanin OM, Abd-El-Latif LM, Ramadan NI. Cryp- tosporidium gastroenteritis in Egyptian children with acute lymphoblastic leukemia: Magnitude of the problem. Infection 2012; 40: 279–84. DOI: 10.1007/s15010-011-0230-5 154. Fereig RM, AbouLaila MR, Mohamed SG, et al. Serological detection and epidemiology of Neospora caninum and Cryptosporidium parvum antibodies in cattle in southern Egypt. Acta Trop 2016; 162: 206–11. DOI: 10.1016/j.actatrop- ica.2016.06.032 155. Masatani T, Fereig RM, Otomaru K, et al. Seroprevalence of Cryptosporidium parvum and Neospora caninum in cattle in the southern Kyu- shu region of Japan. Parasitol Int 2018; 67: 763– 7. DOI: 10.1016/j.parint.2018.08.001 156. Amar CF, Dear PH, McLauchlin J. De- tection and identification by real time PCR-RFLP analyses of Cryptosporidium species from human feces. Lett Appl Microbiol 2004; 38: 217–22. DOI: 10.1111/j.1472-765X.2004.01473.x 157. Xiao L, Escalante L, Yang C. Phylogenetic analysis of Cryptosporidium parasites based on the small-subunit rRNA gene locus. Appl Envi- ron Microbiol 1999; 65: 1578–83. DOI: 10.1128/ aem.65.4.1578-1583.1999 158. Mahfouz ME, Mira N, Amer S. Prevalence and genotyping of Cryptosporidium spp. in farm animals in Egypt. J Vet Med Sci 2014; 76: 1569– 75. DOI: 10.1292/jvms.14-0272 159. Spano F, Putignani L, McLauchlin J. PCR-R- FLP analysis of the Cryptosporidium oocyst wall pro- tein (COWP) gene discriminates between C. wrairi and C. parvum, and between C. parvum isolates of human and animal origin. FEMS Microbiol Lett 1997; 150: 209–17. DOI: 10.1016/s0378-1097(97)00115-8 160. Jex AR, Gasser RB. Genetic richness and diversity in C. hominis and C. parvum reveals ma- jor knowledge gaps and a need for the application of Bnext generation technologies research review. Biotechnol Adv 2010; 28: 17–26. DOI: 10.1016/j. biotechadv.2009.08.003 161. de Graaf DC, Vanopdenbosch E, Orte- ga-Mora LM, Abbassi H, Peeters JE. A review of the importance of cryptosporidiosis in farm animals. Int J Parasitol 1999; 29: 1269–87. DOI: 10.1016/ s0020-7519(99)00076-4 162. Amer S, Honma H, Ikarashi M, et al. Cryptosporidium genotypes and subtypes in dairy calves in Egypt. Vet Parasitol 2010; 169: 382–6. DOI: 10.1016/j.vetpar.2010.01.017 163. Ibrahim MA, Abdel-Ghany AE, Abdel-Latef GK, Abdel-Aziz SA, Aboelhadid SM. Epidemiology and public health significance of Cryptosporid- ium isolated from cattle, buffaloes, and humans in Egypt. Parasitol Res 2016; 115: 2439–48. DOI: 10.1007/s00436-016-4996-3 164. Alagappan A, Bergquist PL, Ferrari BC. Development of a two-color fluorescence in situ hybridization technique for species-level identifi- cation of human-infectious Cryptosporidium spp. Appl Environ Microbiol 2009; 75: 5996–8. DOI: 10.1128/AEM.00643-09 165. Wong YP, Othman S, Lau YL, Radu S, Chee HY. Loop-mediated isothermal amplification (LAMP): a versatile technique for detection of mi- Zbornik_1_2022_22.4.22.indd 25 22/04/2022 09:53:33 26 W. A. A. El-Ghany cro-organisms. J Appl Microbiol 2018; 124: 626– 43. DOI: 10.1111/jam.13647 166. Fayer R, Ungar BLP. Cryptosporidium spp. and cryptosporidiosis. Microbiol Rev 1986; 50: 458–83. 167. Abou-Eisha AM. Cryptosporidial infection in man and farm animals in Ismailia governorate. Vet Med J Giza 1994; 42: 107–11. 168. Abou-Eisha AM, Hussein MM, Abdel-Aal AA, Saleh RE. Cryptosporidium in drinking water sources and its zoonotic importance. Minufiya Vet J 2000; 1: 101–6. 169. Xiao L, Ryan U. Cryptosporidium. In: Xiao L, Ryan U, eds. Biology of foodborne parasites. Boca Raton : CRC Press, 2015: 77–95. 170. Preiser G, Preiser L, Madeo L. An outbreak of cryptosporidiosis among veterinary science stu- dents who work with calves. J Am Coll Health 2003; 51: 213–5. DOI: 10.1080/07448480309596353 171. Gait R, Soutar RH, Hanson M, Fraser C, Chalmers R. Outbreak of cryptosporidiosis among veterinary students. Vet Rec 2008; 162: 843–5. DOI: 10.1136/vr.162.26.843 172. Graczyk TK, Fayer R, Cranfield MR. Zo- onotic transmission of Cryptosporidium parvum: implications for waterborne cryptosporidiosis. Parasitol Today 1998; 13: 348–51. DOI: 10.1016/ s0169-4758(97)01076-4 173. Graczyk TK, Majewska AC, Schwab KJ. The role of birds in dissemination of human wa- terborne enteropathogens. Trends Parasitol 2008; 24: 55–9. DOI: 10.1016/j.pt.2007.10.007 174. Plutzer J, Tomor B. The role of aquatic birds in the environmental dissemination of human pathogenic Giardia duodenalis cysts and Cryptosporidium oocysts in Hungary. Par- asitol Int 2009; 58: 227–31. DOI: 10.1016/j. parint.2009.05.004 175. Wong SSY. The sick returned traveller. Top Updat Hong Kong Coll Pathol 2016; 11: 1–10. 176. Chen XM, Keitely JS, Paya CV, Larusso NF. Cryptosporidiosis. N Engl J Med 2002; 346: 1723–31. DOI: 10.1056/nejmra013170 177. Thomson S, Hamilton CA, Hope JC, et al. Bovine cryptosporidiosis: impact, host-parasite interaction and control strategies. Vet Res 2017; 48: 42. DOI: 10.1186/s13567-017-0447-0 178. Morgan-Ryan UM, Fall A, Ward LA, et al. Cryptosporidium hominis n. sp. (Apicomplexa: Cryptosporidiidae) from Homo sapiens. J Eu- karyot Microbiol 2002; 49: 433–40. DOI: 10.1111/ j.1550-7408.2002.tb00224.x 179. Chappell CL, Okhuysen PC, Langer- Curry RC, et al. Cryptosporidium meleagridis in- fectivity in healthy adult volunteers, Am J Trop Med Hyg 2011; 85: 238–42. DOI: 10.4269/ ajtmh.2011.10-0664 180. Xiao L. Molecular epidemiology of crypto- sporidiosis: an update. Exp Parasitol 2010; 124: 80–9. DOI: 10.1016/j.exppara.2009.03.018 181. Xiao L, Feng Y. Zoonotic cryptosporidio- sis. FEMS Immunol Med Microbiol 2008; 52: 309– 23. DOI: 10.1111/j.1574-695x.2008.00377.x 182. Chalmers RM, Giles M. Zoonotic cryp- tosporidiosis in the UK: challenges for con- trol. J Appl Microbiol 2010; 109: 1487–97. DOI: 10.1111/j.1365-2672.2010.04764.x 183. Elwin K, Hadfield SJ, Robinson G, Chalm- ers RM. The epidemiology of sporadic human in- fections with unusual cryptosporidia detected during routine typing in England and Wales, 2000–2008. Epidemiol Infect 2012; 140: 673–83. DOI: 10.1017/s0950268811000860 184. Insulander M, Silverlas C, Lebbad M, et al. Molecular epidemiology and clinical manifesta- tions of human cryptosporidiosis in Sweden. Epi- demiol Infect 2013; 141: 1009–20. DOI: 10.1017/ s0950268812001665 185. Steiner KL, Ahmed S, Gilchrist CA, et al. Species of cryptosporidia causing subclinical in- fection associated with growth faltering in rural and urban Bangladesh: a birth cohort study. Clin Infect Dis 2018; 67: 1347–55. DOI: 10.1093/cid/ ciy310 186. Stensvold CR, Beser J, Axén C, Lebbad M. High applicability of a novel method for gp60- based subtyping of Cryptosporidium meleagridis. J Clin Microbiol 2014; 52: 2311–9. DOI: 10.1128/ JCM.00598-14 187. Korpe PS, Gilchrist C, Burkey C, et al. Case-control study of Cryptosporidium transmis- sion in Bangladeshi households. Clin Infect Dis 2019; 68: 1073–9. DOI: 10.1093/cid/ciy593 188. Messenger AM, Barnes AN, Gray GC. Reverse zoonotic disease transmission (zooan- throponosis): a systematic review of seldom-doc- umented human biological threats to animals. PLoS One 2014; 9: e89055. DOI: 10.1371/jour- nal.pone.0089055 189. Aldeyarbi HM, El-Ezz NM, Karanis P. Cryptosporidium and cryptosporidiosis: the Afri- can perspective. Environ Sci Pollut Res 2016; 23: 13811–21. DOI: 10.1007/s11356-016-6746-6 190. Kotloff KL, Nataro JP, Blackwelder WC, Zbornik_1_2022_22.4.22.indd 26 22/04/2022 09:53:33 27Avian cryptosporidiosis: a significant parasitic disease of public health hazard et al. Burden and aetiology of diarrhoeal dis- ease in infants and young children in developing countries (The Global Enteric Multicenter Study, GEMS): a prospective, case-control study. Lan- cet 2013; 382: 209–22. DOI: 10.1016/s0140- 6736(13)60844-2 191. Gabr NS, Ahmad AK, Belal US, Abdel-Ha- feez EH, Abd Rabou RAM. Prevalence of Crypto- sporidium species in human faecal specimens in Minia Governorate, Egypt. Malaysian J Med Res 2018; 29: 225–9. 192. Abdel-Hafeez EH, Ahmad AK, Ali BA, Mo- slam FA. Opportunistic parasites among immuno- suppressed children in Minia District, Egypt. Ko- rean J Parasitol 2012; 50: 57–62. DOI: 10.3347/ kjp.2012.50.1.57 193. Helmy YA, Krucken J, Nockler K, von Samson-Himmelstjerna G, Zessin KH. Molecu- lar epidemiology of Cryptosporidium in livestock animals and humans in the Ismailia province of Egypt. Vet Parasitol 2013; 193: 15–24. DOI: 10.1016/j.vetpar.2012.12.015 194. Naser ME, Younis MS, Bayoumi IR, et al. Evaluation of nanogold-beads-based en- zyme-linked immunosorbent assay for detection of Cryptosporidium antigen in stool samples of di- arrheic patients. Benha Med J 2017; 34: 88–92. DOI: 10.4103/bmfj.bmfj_109_17 195. Mousa KM, Abdel-Tawab AH, Khalil HH, El-Hussieny NA. Diarrhea due to parasites particularly Cryptosporidium parvum in great Cairo, Egypt. J Egypt Soc Parasitol 2010; 40: 439–50. 196. Abdel-Maboud AI, Rossignol JF, El-Kady MS, Mostafa MS, Kabil SM. Cryptosporidiosis in Benha, study of some recent modalities in diag- nosis and treatment. J Egypt Soc Parasitol 2000; 30: 717–25. 197. Ali MS, Mahmoud LA, Abaza BE, Rama- dan MA. Intestinal spore-forming protozoa among patients suffering from chronic renal failure. J Egypt Soc Parasitol 30: 93–100. 198. Shoukry NM, Dawoud HA, Haridy FM. Studies on zoonotic cryptosporidiosis parvum in Ismailia Governorate, Egypt. J Egypt Soc Parasitol 2009; 39: 479–88. 199. Hassan SI, Sabry H, Amer NM, et al. In- cidence of cryptosporidiosis in immunodeficient cancer patients in Egypt. J Egyptian Soc Parasitol 2002; 32: 33–46. 200. Antonios SN, Tolba OA, Othman AA, Saad MA. A preliminary study on the prevalence of par- asitic infections in immunocompromised children. J Egypt Soc Parasitol 2010; 40: 617–30. 201. El-Badry AA, Al-Antably ASA, Hassan MA, Hanafy NA, AbuSarea EY. Molecular sea- sonal, age and gender distributions of Cryptospo- ridium in diarrhoeic Egyptians: distinct endemic- ity. Eur J Clin Microbiol 2015; 34(12): 2447–53. DOI: 10.1007/s10096-015-2502-y 202. Chako CZ, Tyler JW, Schultz LG, Chig- uma L, Beerntsen BT. Cryptosporidiosis in peo- ple: it’s not just about the cows. J Vet Intern Med 2010; 24: 37–43. DOI: 10.1111/j.1939- 1676.2009.0431.x 203. Joachim A. Human cryptosporidiosis: an update with special emphasis on the situa- tion in Europe. J Vet Med B Infect Dis Vet Public Health 2004; 51: 251–9. DOI: 10.1111/j.1439- 0450.2004.00765.x 204. Barbee SL, Weber DJ, Sobsey MD, Ru- tala WA. Inactivation of Cryptosporidium parvum oocyst infectivity by disinfection and sterilization processes. Gastrointest Endosc 1999; 49: 605–11. DOI: 10.1016/s0016-5107(99)70389-5 205. Semenza JC, Nichols G. Cryptosporid- iosis surveillance and water-borne outbreaks in Europe. Eur Commun Dis Bull 2007; 12: 120–3. DOI: 10.2807/esm.12.05.00711-en 206. Guerrant RL. Cryptosporidiosis: an emerging, highly infectious threat. Emerg Infect Dis 1997; 3: 51–7. DOI: 10.3201/eid0301.970106 207. King B, Fanok S, Phillips R, Swaffer B, Monis P. Integrated Cryptosporidium assay to de- termine oocyst density, infectivity, and genotype for risk assessment of source and reuse water. Appl Environ Microbiol 2015; 81: 3471–81. DOI: 10.1128/AEM.00163-15 208. Lindsay DS, Blagburn BL, Sundermann CA, Ernest JA. Chemoprophylaxis of cryptospo- ridiosis in chickens, using halofuginone, sali- nomycin, lasalocid, or monensin. Am J Vet Res 1987; 48: 354–5. 209. Shahiduzzaman M, Daugschies A. Ther- apy and prevention of cryptosporidiosis in an- imals. Vet Parasitol 2012; 188: 203–14. DOI: 10.1016/j.vetpar.2012.03.052 210. Hassan D, Farghali M, Eldeek H, et al. An- tiprotozoal activity of silver nanoparticles against Cryptosporidium parvum oocysts: new insights on their feasibility as a water disinfectant. J Micro- biol Meth 2019; 165: 105698. DOI: 10.1016/j.mi- met.2019.105698 211. Aly I, Taher H, El-Feky F. Efficacy of low Zbornik_1_2022_22.4.22.indd 27 22/04/2022 09:53:33 28 W. A. A. El-Ghany and high dose of paromomycin sulfate for treat- ment of cryptosporidiosis in immunosuppressed infected-mice. Global Vet 2015; 15: 137–43. 212. Abdel Megeed KN, Hammam AM, Morsy GH, Khalil FM. Control of cryptosporidiosis in buffalo calves using garlic (Allium sativum) and nitazoxanide with special reference to some bio- chemical parameters. Global Vet 2015; 14: 646– 55. 213. Carey CM, Lee H, Trevors JT. Biology, persistence and detection of Cryptosporidium parvum and Cryptosporidium hominis oocyst. Water Res 2003; 38: 818–32. DOI: 10.1016/j. watres.2003.10.012 214. Ryan UNA, Fayer R, Xiao L. Cryptospo- ridium species in humans and animals: cur- rent understanding and research needs. Par- asitology 2014; 141: 1667–85. DOI: 10.1017/ s0031182014001085 215. Acikgoz Y, Ozkaya O, Bek K, et al. Cryptosporidiosis: a rare and severe infec- tion in a pediatric renal transplant recipient. Pediatr Transplant 2012; 16: E115–9. DOI: 10.1111/j.1399-3046.2011.01473.x 216. Wei A, Shibamoto T. Antioxidant/lipoxy- genase inhibitory activities and chemical composi- tions of selected essential oils. J Agric Food Chem 2010; 58: 7218–25. DOI: 10.1021/jf101077s 217. Abouel-Nour MF, El-Shewehy DMM, Ha- mada SF, Morsy TA. The efficacy of three medicinal plants; garlic, ginger and mirazid and a chemical drug metronidazole against Cryptosporidium par- vum: II- histological changes. J Egypt Soc Parasi- tol 2016; 46: 185–200. DOI: 10.12816/0026164 218. Kim HC, Healey JM. Effects of pine bark extract administered to immunosuppressed adult mice infected with Cryptosporidium parvum. Am J Chin Med 2001; 29: 469–75. DOI: 10.1142/ s0192415x01000484 219. Wahba AA. Studies on efficacy of garlic extract on cryptosporidiosis in experimentally in- fected mice. Egypt J Agric Res 2003; 81: 795–805. 220. Abu El Ezz NMT, Khalil AM, Shaapan RM. Therapeutic effect of onion (Allium cepa) cin- namon (Cinnamomum zeylanicum) oils on cryp- tosporidiosis in experimentally infected mice. Global Vet 2001; 7: 179–83. 221. Gaafar MR. Efficacy of Allium sativum (garlic) against experimental cryptosporidiosis. Alex J Med 2011; 48: 59-66. 222. Toulah FH, El-Shafei AA, Al-Rashidi HS. Evaluation of garlic plant and indinavir drug efficacy in the treatment of cryptosporidi- osis in experimentally immune-suppressed rats. J Egypt Soc Parasitol 2012; 42: 321–8. DOI: 10.12816/0006320 223. Nasir A, Avais M, Khan MS, et al. Treat- ing Cryptosporidium parvum infection in calves. J Parasitol 2013; 99: 715–7. DOI: 10.1645/12- 42.1 224. Zaki WM, El-Amir YO. Therapeutic effi- cacy of a cysteine proteases inhibitor (phenyl vi- nyl sulfone) either alone or combined with Nigella sativa on experimental cryptosporidiosis. J Egypt Soc Parasitol 2018; 48: 165–74. DOI: 10.12816/ JESP.2018.77484 225. Sadek HA, Abdel-Rahman SM, Bakir HY, et al. The potential convention of garlic and black seed different extracts as an effective treatment of Cryptosporidium spp.: an experimental study. J Egypt Soc Parasitol 2020; 50: 613–21. DOI: 10.12816/JESP.2020.131094 226. Fareed G, Scolaro M, Jordan W, Sanders N. The use of a high-dose garlic preparation for the treatment of Cryptosporidium parvum diar- rhea. Int Conf AIDS 1996; 11: 288–97. Zbornik_1_2022_22.4.22.indd 28 22/04/2022 09:53:33 29Avian cryptosporidiosis: a significant parasitic disease of public health hazard KRIPTOSPORIDIOZA PTIC: POMEMBNA PARAZITSKA BOLEZEN, NEVARNA ZA JAVNO ZDRAVJE W. A. A. El-Ghany Izvleček: Kriptosporidioza je ena najpomembnejših zoonotskih parazitskih bolezni, ki prizadene številne gostiteljske vrste. Bolezen je razširjena po vsem svetu. Vrste Cryptosporidium lahko prizadenejo različne ptičje gostitelje in povzročijo veliko gos- podarsko škodo. Resnost simptomov kriptosporidioze pri pticah je različna, od asimptomatične bolezni do hudih črevesnih in/ ali dihalnih znakov z visoko smrtnostjo. Diagnoza okužbe s parazitom Cryptosporidium temelji predvsem na mikroskopskem od- krivanju oocist, seroloških metodah ali molekularnih tehnikah za identifikacijo različnih vrst povzročitelja. Ljudje in živali so zelo dovzetni za okužbo z različnimi vrstami Cryptosporidium, ki so posledica zaužitja kontaminirane hrane ali vode z oocistami ali neposrednega stika z okuženimi gostitelji. Za preprečevanje in nadzor bolezni pri okuženih živalih, pticah in ljudeh ali v njihovi oko- lici so bile uporabljene različne strategije. Namen tega preglednega članka je bil zato razjasniti vrste povzročiteljev in razširjenost kriptosporidioze ptic, dovzetnost za okužbo in način prenosa ter klinično sliko, laboratorijsko diagnostiko, zoonotski pomen in strategije preprečevanja in nadzora bolezni. Ključne besede: ptičji; Cryptosporidium; diagnoza; človeški Zbornik_1_2022_22.4.22.indd 29 22/04/2022 09:53:33