Introduction: Streptococcus pneumoniae in asymptomatic manner colonize the mucous membranes of the nasopharynx of children and adults, but can cause serious illness in the media which are naturally sterile. In 5-40% of healthy population this bacteria colonize the nasopharyngeal mucosa thanks to the surface adhesin protein, which allow the bacteria to attach to the epithelial cells. The normal nasopharyngeal microflora retains pneumococcus in a small number and does not allow it to express its pathogenic potential and cause disease. If this dominance of the normal microflora is violated, after adherence and local duplication, pneumococcus can spread to the middle ear, sinuses or lungs. Colonization is more common in children than in adults. Goal: The goal of this study was to determine the prevalence of the carrier state and susceptibility of pneumococcal strains that circulate in the outpatient population of Sarajevo Canton as a potential source of infection. Material and methods: In the microbiological laboratory of the Institute of Public Health of Canton Sarajevo in the period from July 1, 2013 until April 15, 2014 were analyzed swabs of the nose and nasopharynx, eye and ear from a total of 4109 outpatients. Swabs were inoculated on blood agar nutrient medium. Then was performed catalase test, preparation by Gram and susceptibility test on Optochin. Isolates positive for S. pneumoniae were subjected to in vitro assays to investigate the antimicrobial susceptibility/resistance. Results: Out of 4109 analyzed swabs the pneumococcus positive was 180 (4.38%). Of these, 137 (76.11%) nasal and nasopharyngeal swabs, 33 (18.33%) of the eyes and 10 (5.56%) ear. The highest number of positive swabs were isolated in children aged 6 years and less, a total of 168 (93.33%), in children aged 7-13 years were positive 7 (3.89%), while among respondents aged 14-20 years only 5 (2.78%). Conclusions: The most common site for isolation of pneumococci is the nose and throat, and the most common carriers of these bacteria are children under 6 years of age. Determining the prevalence of the carrier state contributes to the improvement of preventive measures to reduce the risk of infection and possible sequels.
[Med Arch 2015; 69(3.000): 177-180]

pneumococcus, carriage, prevalence, Optochin