NASOPHARYNGEAL CARRIAGE OF STREPTOCOCCUS PNEUMONIAE  
AND SEROTYPES INDENTIFIED AMONG NURSING HOME RESIDENTS  
IN COMPARISON TO THE ELDERLY AND PATIENTS YOUNGER THAN  
65 YEARS LIVING IN DOMESTIC ENVIRONMENT
Maja KOLŠEK-ŠUŠTERŠIČ1*, Andreja BEG KRASNIČ1, Verica MIOČ2, Metka PARAGI2, Janez RIFEL3
1Community Health Centre Ljubljana, Metelkova 9, 1000 Ljubljana, Slovenia
2National Laboratory of Health, Environment and Food, Centre for Medical Microbiology,  
Department for Public Health Microbiology, Grablovičeva 44, 1000 Ljubljana, Slovenia   
3University of Ljubljana, Faculty of Medicine, Department of Family Medicine,  
Poljanski nasip 58, 1000 Ljubljana, Slovenia   
Received: Jan 25, 2016
Accepted: Mar 23, 2017
Original scientific article
Introduction. In Slovenia, there is little data available on pneumococcal vaccination rates and no data on 
asymptomatic NPCR and serotypes in the population of nursing home residents in comparison to the elderly 
living in domestic environment, therefore the goal was to gain these data.
Methods. A cross sectional epidemiological study was performed. Nasopharyngeal swabs from 151 nursing home 
residents, 150 elderly living in domestic environment, and 38 adults less than 65 years old were collected twice 
(in two consecutive years). The swabs were analysed for pneumococcal identification and serotyping. Patient 
data were collected from medical files and medical history. 
Results. No statistically significant differences in NPCR were seen between compared groups in two consecutive 
years. An average NPCR in two consecutive years in nursing home residents was 1.45%, in the elderly living in 
domestic environment 0.85%, and in adults less than 65 years old 7.05%. Serotypes identified among nursing 
home residents were 6B and 9N, among the group of elderly living in domestic environment, 6A and among 
adults less than 65 years old, 35F, 18C and 3. Pneumococcal vaccination rates were low (3.3% in nursing home 
residents, 6% in the elderly from domestic environment and 0% in the group of adults less than 65 years old). 
Conclusions. Our data suggests that NPCR and the proportion of people vaccinated with pneumococcal vaccine 
among the elderly are low. We identified different serotypes in all groups, only one person was a chronic carrier 
(serotype 35F). 
Izhodišča. V Sloveniji je malo podatkov o stopnji precepljenosti s pnevmokoknimi cepivi in ni dostopnih 
podatkov o nosilstvu pnevmokoka v nosnem žrelu ter o serotipih med oskrbovanci doma starejših občanov 
(DSO) v primerjavi s starostniki, ki živijo v domačem okolju, zato je bil namen raziskave pridobiti te podatke. 
Metode. Izvedli smo presečno epidemiološko raziskavo. Dvakrat (v dveh zaporednih letih) smo odvzeli brise 
151 oskrbovancem DSO, 150 starostnikom, ki živijo v domačem okolju, in 38 odraslim, mlajših od 65 let. Z 
analizo brisov smo identificirali pnevmokoke in jih serotipizirali. Podatke o bolnikih smo pridobili iz medicinske 
dokumentacije ter iz anamneze.
Rezultati. V nobeni od primerjanih skupin nismo ugotovili razlike v deležu nosilstva pnevmokoka v dveh 
zaporednih letih. Povprečni delež nosilstva v dveh zaporednih letih skupaj je bil med oskrbovanci DSO 
1,45%, med starostniki, ki živijo v domačem okolju, 0,85% ter med odraslimi, mlajšimi od 65 let, 7,05%. Med 
oskrbovanci DSO smo identificirali serotipa 6B in 9N, med starostniki, ki živijo v domačem okolju, serotip 6A 
ter med odraslimi, mlajšimi od 65 let, stereotipe 35F, 18C in 3. Delež cepljenih s pnevmokoknim cepivom je 
bil nizek (3,3% med oskrbovanci DSO, 6% med starostniki, ki živijo v domačem okolju, in 0% med odraslimi, 
mlajšimi od 65 let). 
Zaključki. Glede na naše izsledke sklepamo, da sta delež nosilcev pnevmokoka v nosnem žrelu ter delež oseb, 
cepljenih s pnevmokoknimi cepivi, med starostniki nizka. Identificirani serotipi v vseh skupinah so bili različni, 
odkrili smo le enega kroničnega nosilca (serotip 35F).
ABSTRACT
Keywords: 
S. pneumoniae, 
nasopharyngeal 
carriage, serotype 
identification, 
retirement home 
residents, vaccination
IZVLEČEK
Ključne besede: 
pnevmokok, nosilstvo 
v nosnem žrelu, 
identifikacija serotipov, 
oskrbovanci doma 
starejših občanov, 
cepljenje
*Corresponding author: Tel: ++ 386 41 519 962; E-mail: maja.kolsek@gmail.com
10.1515/sjph-2017-0023 Zdr Varst 2017; 56(3): 172-178
172
NOSILSTVO PNEVMOKOKA V NOSNEM ŽRELU IN IDENTIFIKACIJA SEROTIPOV 
MED OSKRBOVANCI DOMA STAREJŠIH OBČANOV V PRIMERJAVI  
S STAROSTNIKI IN MLAJŠIMI OD 65 LET, KI ŽIVIJO V DOMAČEM OKOLJU
Kolšek-Šušteršič M, Beg Krasnič A, Mioč V, Paragi M, Rifel J. Nasopharyngeal carriage of Streptococcus pneumoniae and serotypes indentified among nursing home 
residents in comparison to the elderly and patients younger than 65 years living in domestic environment. Zdr Varst 2017; 56(3): 172-178.
© Nacionalni inštitut za javno zdravje, Slovenija. 
1 INTRODUCTION
Elderly living in nursing homes represent 5% of the total 
elderly population in Slovenia (1). Among them respiratory 
tract infections are the second most prevalent and 
represent one of the most frequent causes of morbidity, 
mortality and hospital admissions (1-3). In this group, 
pneumonia is regarded a special category due to advanced 
age, numerous co-morbidities and non-specific, but often 
severe disease course, which all contribute to a high (30%) 
mortality rate (2). One of the main pathogens causing 
pneumonia in the group of elderly is S. pneumoniae 
(Streptococcus pneumoniae; 4-7). 
S. pneumoniae is part of the normal nasopharyngeal 
microbial flora (8). Colonization occurs early in life, 
with prevalence of 40% in children and 15% in adults 
(9), transmission between individuals is via aerosol 
(8). Nasopharyngeal colonization is a risk factor for 
pneumococcal diseases: otitis media, pneumonia, sepsis, 
meningitis. Asymptomatic carriers are the main reservoir 
of pneumococci and the principal source of spread among 
new hosts (10). More than 20% of deaths associated with 
pneumococcal infection are supposed to occur among 
people older than 80 years, although nasopharyngeal 
pneumococcal carriage rate (NPCR) in this group is low 
(11, 12). 
The estimated incidence of pneumonia among nursing 
home residents in the United States is 365/1000 residents 
per year and it is significantly higher in comparison to 
elderly living in domestic environment (20-40/1000) 
(13). Due to frequent and sometimes unjustified use of 
antibiotics, numerous antibiotic resistant pneumococcal 
strains develop (4, 13), representing an increasing 
problem worldwide (5, 14).
The incidence of invasive pneumococcal disease in 
Slovenia was 11.9/100,000 in year 2012 (most frequently 
pneumonia) (15). The highest rates were among children 
under 5 years of age (46.2/100,000) and among elderly 
over 65 years of age (27/100,000) (15). Among adults 
most prevalent serotypes, causing invasive pneumococcal 
disease, were 3, 9V, 14, 4, 1, 23F and 19F (15). Similar 
data was found in United States, German and Czech 
studies (16-18).
Although pneumococcal pneumonia is an important 
cause of morbidity and mortality among nursing home 
residents and represents great cost for the society (19), 
pneumococcal vaccination rates remain low (6, 13, 20). 
In situations where vaccination rates within a closed 
population, such as in a nursing home, are less than 
5%, there is a greater risk for pneumococcal infection 
outbreak (6). Pneumococcal vaccination represents 
effective protection from pneumococcal pneumonia 
for an individual and vaccination of critical number of 
individuals can lead to herd immunity effect (6, 21). 
So far, there is little data available on pneumococcal 
vaccination rates (20) and no data on asymptomatic NPCR 
and serotypes in the population of nursing home residents 
in comparison to adults living in domestic environment 
in Slovenia. Therefore the goal of this research is to gain 
these data.
2 METHODS
2.1 Type of a Study and Study Population
We performed a cross sectional epidemiological study, in 
which two swabs were taken from all the participants (one 
swab every year) in two consecutive years (February 2013 
– November 2013 and February 2014 – November 2014). 
The study included 151 nursing home residents from “Dom 
upokojencev center” in Ljubljana, 152 elderly living in 
domestic environment and 38 adults less than 65 years, 
all visiting General practitioners in the same region 
(“Zdravstveni dom Ljubljana Center”). Due to lack of 
data, 2 of the participants in the first year, both from the 
group of elderly living in domestic environment, and one 
participant in the second year, from the group of nursing 
home residents, were excluded from the analysis.
Inclusion criteria were i) no sign of acute respiratory 
infection, ii) living in a defined geographical region in 
a domestic environment or retirement home and iii) 
informed consent form signed by the patient or patient’s 
legal representative.
Exclusion criteria were i) ongoing acute respiratory 
infection, ii) living outside defined geographical 
region, iii) refusal to sign informed consent form by 
patient or patient’s legal representative, iv) the use of 
antibiotics in the two weeks prior to taking the swab, 
and v) immunocompromised patients (hematological 
malignancies, inherited immunodeficiency, HIV, post 
splenectomy status, cancer chemotherapy).
2.2 Data Collection
Recruitment of participants started in the nursing 
home. We asked all the residents from “unit Poljane” 
to participate. On-site recruitment approach, with the 
possibility to turn down the participation was used. 
This was previously identified as one of more successful 
approaches (22). 95 out of 168 decided to join the study. 
We continued in “unit Tabor”, where the random number 
method was used until we included the expected number 
of participants. The same method was used to select 
the participants among elderly patients and adults less 
than 65 years from different General practitioner offices 
at “Zdravstveni dom Ljubljana Center”. These were 
contacted by telephone. 
Case report form was filled in for each participant. 
It included patient’s identification number, gender, 
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age, preceding vaccination data against influenza and 
pneumococcal infections, preceding antibacterial therapy 
(from three months up to two weeks prior to taking the 
swab), data on preschool children contacts, corticosteroid 
or immunosuppressant treatment and data on chronic 
diseases. This data was collected by reviewing patient 
medical files and by taking patient history.
2.3 Nasopharyngeal Swab Collection
We used R Sterile Copan swab (Copan, Brescia, Italy) 
with a universal transport medium to take a sample from 
nasopharynx. Nasopharyngeal space is currently defined 
as the most appropriate spot for S. pneumoniae detection 
(23). The swab was inserted through a nostril about 10 cm 
deep into the nasopharynx, rotated there and removed 
after 5 seconds and inserted directly into the transport 
medium. 
2.4 Streptococcus Pneumoniae Identification and 
Serotyping
The swabs were transferred to the National Laboratory 
of Health, Environment and Food, Centre for Medical 
Microbiology, Department for Public Health Microbiology, 
Laboratory for Public Health Bacteriology, Ljubljana, 
Slovenia no later than 24h after specimen collection, 
where the identification and serotyping of S. pneumonia 
was performed. 
The cultures were grown on Columbia blood agar with 
5% sheep blood and Blood agar with bovine blood, both 
manufactured at the laboratory, and incubated on 35±2 
°C in the 5% CO2 for 48h. The plates were checked for 
the presence of suspected S. pneumoniae colonies after 
24 and 48h of incubation. All suspected colonies based 
on colony morphology and hemolysis were cultured on 
Columbia agar for 24h and then stained by Gram, tested 
for the presence of catalase, optochin sensitivity and bile 
solubility. An isolate was considered to be S. pneumoniae 
if the Gram stain morphology of the isolate showed gram-
positive diplococci, cocci, single or in chains, was catalase 
negative, optochin sensitive and bile soluble. Serotyping 
was performed with the Neufeld-Quellung reaction, using 
specific pneumococcal typing antisera (Omni, pooled, 
group, type and factor) containing specific antibodies 
against pneumococcal capsular polysaccharide type 
antigens (Statens Serum Institute, Copenhagen, Denmark). 
To avoid misidentification of S. pneumoniae like viridians 
group streptococci, a Real-Time PCR Assay targeting Lyt 
A (autolysin) a gen specific for S. pneumoniae,  has been 
used (24).  The DNA isolation was done using the QIAamp 
DNA Mini Kit (Qiagen, Hilden, Germany).
2.5 Statistical Analysis
The collected data was analyzed with SPSS, version 20.0.0. 
Pearson Chi Square test was used to test the differences 
between different groups of participants. A value of 
p<0.05 was used as a limit to describe significant scientific 
differences between groups. 
3 RESULTS
3.1 Description of the Groups
In the group of nursing home residents, the average age 
was 85.24 years (range 67-105 years), 120 (79.4%) were 
females and 31 (20.6%) were males. 
In the group of elderly from domestic environment, the 
average age was 82.07 years (range 65-97 years), 115 
(76.7%) were females and 35 (23.3%) were males. 
In the group of adults less than 65 years the average age 
was 55.34 years (range 47-64 years), 19 (50%) were females 
and 19 (50%) were males. 
3.2 Swab Results
NPCR were low in groups of elderly studied in two 
consecutive years. In the group of adults less than 65 years 
NPCR were higher, in the second year NPCR in this group 
was significantly higher, compared to others (p<0.05) 
(Table 1).
71 participants were eliminated from the study after the 
first year; 42 participants turned down the second swab 
(1 from nursing home residents, 38 elderly from domestic 
environment and 3 adults less than 65 years) and 29 due to 
death (20 nursing home residents, 8 elderly from domestic 
environment, 1 adult less than 65 years).
Table 1. Number of positive swabs in different groups in two 
consecutive years.
First year
Second year
* p<0.05
2 (1.3%) n=151
2 (1.6%) n=129
1 (0.7%) n=150
1 (1%) n=104
2 (5.3%) n=38
3 (8.8%) n=34*
Nursing home 
residents
Elderly 
domestic 
environment
Adults 
< 65 years
3.2.1 Characteristics of Participants with Positive Swab 
Results
There were five positive swab results in the first year (Table 
2) and six in the second (Table 3). Serotype 6B and a non-
typeable S. pneumoniae was identified in nursing home 
residents in the first year (Table 2), in the second year 
serotypes 6B and 9N were identified (Table 3). In the group 
of elderly from domestic environment a non-typeable 
10.1515/sjph-2017-0023 Zdr Varst 2017; 56(3): 172-178
175
S. Pneumoniae was identified in the first year (Table 2) 
and 6A serotype in the second year (Table 3). In adults 
less than 65 years a non-typeable S. pneumoniae and 35F 
serotype were identified in the first year (Table 2) and 35F 
serotype (chronic carrier) and 18C and 3 in the second 
year (Table 3). 
Table 2.
Table 3.
Characteristics of participants with positive swab result and S. pneumoniae serotypes in the first year.
Characteristics of participants with positive swab result and S. pneumoniae serotypes in the first year.
Age
Gender 
Group 
Influenza vaccinationa
Pneumococcal vaccinationb
Antibiotics 3 months prior to swab
Preschool children contacts
Corticosteroid treatmentc
1 chronic illness
2 chronic illnesses
≥ 3 chronic illnesses
S. pneumoniae serotype
Death after the first year
Second swab refusal
Age
Gender
Group
Influenza vaccinationa
Pneumococcal vaccinationb
Antibiotics 3 months prior to swab
Preschool children contacts
Corticosteroid treatmentc
1 chronic illness
2 chronic illnesses
≥ 3 chronic illnesses
S. pneumoniae serotype
a in the previous season, b in the last 5 years, c in the last month, NT, non-typeable; /, not applicable
a in the previous season, b in the last 5 years, c in the last month; /, not applicable
88 years
Female 
Nursing Home
No 
No 
No 
No 
No 
/
/
Yes 
NT
No 
No 
86 years
Male 
Nursing Home
No
No
No 
No 
No 
/
Yes 
/
6B
77 years 
Female 
Nursing Home
No 
No 
No 
No 
No 
/
Yes 
/
9N
80 years
Female
Domestic 
Environment
No 
No 
No 
No 
No 
/
Yes 
/
6A
47 years 
Male 
Adults 
<65 years
No 
No 
No 
No 
No 
No 
No 
No 
35F
58 years 
Male 
Adults 
<65 years
No 
No
Yes 
Yes 
Yes 
Yes 
/
/
18C
60 years 
Female 
Adults 
<65 years
No 
No 
No 
Yes 
No 
No 
No 
No 
3
78 years
Male 
Nursing Home
Yes 
Yes 
No 
No 
Yes 
/
/
Yes 
6B
Yes 
/
80 years
Female 
Domestic Environment
No 
No 
No
No 
No 
/
Yes 
/
NT 
No 
No 
47 years
Male 
Adults <65 years
No 
No 
No 
No 
No 
No
No
No
35F
No 
No 
58 years
Male 
Adults <65 years
No 
No 
Yes 
Yes 
Yes 
Yes 
/
/
NT
No 
No 
Participant 
Nr. 1
Participant 
Nr. 1’
Participant 
Nr. 2’
Participant 
Nr. 3’
Participant 
Nr. 4’
Participant 
Nr. 5’
Participant 
Nr. 6’
Participant 
Nr. 3
Participant 
Nr. 2
Participant 
Nr. 4
Participant 
Nr. 5
10.1515/sjph-2017-0023 Zdr Varst 2017; 56(3): 172-178
176
3.2.2 Characteristics of Participants with Negative 
Swab Results
The rate of influenza vaccination was significantly lower in 
the group of adults less than 65 years, compared to both 
groups of elderly, the rate of influenza vaccination was 
significantly higher in the group of nursing home residents, 
compared to elderly from domestic environment (Table 4). 
The rate of pneumococcal vaccination was low in all the 
groups, there was no statistically significant difference 
(Table 4). There was also no difference considering 
preschool children contacts and immunosuppressant 
therapy. Antibiotic consumption rate was significantly 
higher in both groups of elderly, compared to adults less 
than 65 years and the number of comorbidities (≥3) was 
significantly higher in the group of nursing home residents, 
compared to others. Death incidence was significantly 
higher among nursing home residents, compared to the 
other two groups, whereas the rate of second swab 
refusal, was significantly higher in the group of elderly 
living in domestic environment, compared to others. 
Table 4. Characteristics of participants with negative swab results in two consecutive years.
Influenza  vaccinationa
Pneumococcal vaccinationb
Antibiotics 3 months 
prior to swab
Preschool children contacts
Corticosteroid treatmentc
1 chronic illness
2 chronic Illnesses
≥ 3 chronic illnesses
Death after the first year
Second swab refusal
a in the previous season, b in the last 5 years, c in the last month, *, p<0.05 – see discussion
Yes
No 
Unknown 
Yes 
No
Unknown 
Yes 
No
Unknown 
Yes
No
Unknown 
Yes 
No 
Unknown 
Yes
Yes 
Yes
Yes
No
Yes
No 
50 (33.6%)*
99 (66.4%)
/
4 (2.7%)
145 (97.3%)
/
43 (28.9%)*
106 (71.1%)
/
29 (19.5%)
119 (79.9%)
1 (0.6%)
9 (6%)
140 (94%)
/
38 (25.5%)
50 (33.6%)
47 (31.6%)*
19 (12.8%)*
130 (87.2%)
1 (0.7%)
148 (99.3%)
23 (18.1%)
63 (49.6%)
41 (32.3%)
4 (3.1%)
123 (96.9%)
/
37 (29.1%)
90 (70.9%)
/
26 (20.5%)
100 (78.7%)
1 (0.8%)
6 (4.7%)
121 (95.3%)
/
35 (27.6%)
42 (33.1%)
38 (29.9%)
31 (20.8%)
118 (79.2%)
/
9 (6%)
139 (93.3%)
1 (0.7%)
19 (12.8%)*
130 (87.2%)
/
38 (25.5%)
111 (74.5%)
/
6 (4%)
143 (96%)
/
64 (43%)
43 (28.9%)
21 (14.1%)
8 (5.4%)
141 (94.6%)
38 (25.6%)*
111 (74.4%)
2 (5.6%)
34 (94.4%)*
/
0
36 (100%)
/
5 (13.9%)
31 (86.1%)
/
14 (38.9%)
22 (61.1%)
/
0
36 (100%)
/
11 (30.6%)
5 (13.9%)
4 (11.1%)
1 (2.8%)
35 (97.2%)
3 (11.2%)
32 (88.8%)
20 (19.4%)
56 (54.4%)
27 (26.2%)
8 (7.8%)
94 (91.2%)
1 (1%)
12 (11.7%)
91 (88.3%)
/
28 (27.2%)
75 (72.8%)
/
4 (3.9%)
99 (96.1%)
/
43 (41.7%)
28 (27.2%)
14 (13.6%)
2 (6.4%)
28 (90.3%)
1 (3.3%)
/
31 (100%)
/
4 (12.9%)
27 (87.1%)
/
12 (38.7%)
19 (61.3%)
/
/
31 (100%)
/
10 (32.3%)
4 (12.9%)
3 (9.7%)
Nursing home residents
First year First year First yearSecond year Second year Second year
Adults <65 yearsElderly domestic environment
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4 DISCUSSION
Swab analysis in two consecutive years in nursing home 
residents showed a NPCR of 1.45% on average, which is 
similar to the data found in the United States study among 
retirement community residents (25). Some characteristics 
of nursing home residents in our study, such as a higher 
number of patients with two or more comorbidities in the 
group of nursing home residents and a more common use 
of antibiotics in this group, were similar to the data found 
in studies by Lee and Sundvall (26, 27). An average NPCR 
in the group of elderly living in domestic environment in 
two consecutive years was 0.85%, which also correlates to 
some studies conducted among the elderly, where NPCR 
were 0.32% and 5.3%, respectively (28, 12). Most of the 
pneumococci isolated were serotyped, some of them 
were non-typeable, which means they did not have the 
polysaccharide capsule. 
6B and 9N serotypes are present, along with other 
serotypes, in the 23-valent polysaccharide pneumococcal 
vaccine (PPV23); moreover, 6B is also present in the 
13-valent conjugate pneumococcal vaccine (PCV13). The 
one S. pneumoniae carrier, who was vaccinated with PPV23 
vaccine, carried a 6B serotype. Vaccination with this type 
of vaccine only prevents invasive pneumococcal disease, 
whereas vaccination with PCV13 vaccine also prevents 
nasopharyngeal colonization (29). A 6A serotype, which 
was identified in the participant from the group of the 
elderly from domestic environment, may have a potential 
to cause micro-epidemics in closed communities; it is 
present in the PCV13 vaccine (30). 
Although NPCR among the elderly are low, this 
group represents a high risk population for invasive 
pneumococcal disease. This might implicate that long-
term pneumococcal carriage among the elderly is rare, 
and that newly acquired pneumococci are responsible for 
invasive pneumococcal disease (31, 32). Seasonality also 
affects pneumococcal carriage rates - pneumococci are 
transmitted better during cooler and drier months (33).
The nasopharyngeal swab analysis among adults less 
than 65 years old showed that pneumococcal carriage 
rates were higher in this group in comparison to the 
elderly population – 5.3% in the first year and 8.8% in 
the second year. This may be because the participants 
from this group have more preschool children contacts 
(39.5%), compared to the groups of the elderly, although 
statistically significant difference was not confirmed 
in this case. Adults less than 65 years old carried 35 F 
(chronic carrier), 18C, 3 and a non-typeable serotype. 
None of the participants were vaccinated with either of 
pneumococcal vaccines.
The strong side of this study is that it is the first study 
addressing the topic of pneumococcal carriage and 
serotype identification among nursing home residents and 
the elderly living in domestic environment in Slovenia, 
and that the results of this study (low NPCR and serotype 
diversity) are consistent with foreign studies (34). There 
are also some limitations to this study. The first is that 
the sample is not representative, since it includes only 
participants from one nursing home and one community 
health center in the same region, and as the number of 
participants is not very high. The second limitation is that 
the study was not conducted in the coolest and driest 
months of the year, which might have influenced our 
results. 
Although the NPCR among nursing home residents are low, 
the incidence of pneumonia (3) and the mortality rate in 
this population are significantly higher in comparison to 
the group of the elderly living in domestic environment 
(30% vs.16.7%) (2). In 2012, 81% of invasive pneumococcal 
infections in the population >65 years of age in Slovenia 
were caused with serotypes included in the PCV13 vaccine 
and 95% with serotypes included in the PPV23 vaccine (15). 
Pneumococcal vaccines are important means of invasive 
disease prevention, and are related to a lower mortality 
rate from pneumococcal pneumonia (6); nevertheless, 
the vaccination rates remain low also according to our 
data (3.3% in nursing home residents and 6% in the elderly 
from domestic environment). It is necessary to increase 
the number of vaccinated elderly. 
5 CONCLUSIONS
Our data suggests that NPCR among the elderly are low 
and not significantly different in nursing home residents, 
compared to the elderly living in domestic environment. 
We identified different serotypes in all groups, only one 
person was a chronic carrier (serotype 35F). Our data also 
shows that pneumococcal vaccination rates are low in all 
compared groups, despite the benefits the vaccination 
brings. 
CONFLICTS OF INTEREST
The authors declare that no conflicts of interest exist.
FUNDING
The Swabs and S. pneumoniae identification and 
serotyping were financed by Pfizer Luxembourg SARL.
ETHICAL APPROVAL
The Committee of the Republic of Slovenia for medical 
ethics approved the study on 19.12.2011, Nr. 72/11/11.
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178
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