Pneumococcal Nasopharyngeal Carriage in Young Healthy Children After Pneumococcal Conjugate Vaccine in Turkey

Abstract

Aims: To determine the prevalence of nasopharyngealcarriage of Streptococcus pneumoniae in healthy childrenaged 0-6 years who were vaccinated with pneumococcalconjugate vaccine.Methods: This cross-sectional study was conducted on150 healthy Turkish children between 1 month and 6years of age. Serotyping was performed and risk factorsof carriage were evaluated.Results: The overall carriage rate was 14%. Vaccinetype serotypes were determined in 17 (12.6%) childrenwho received full-dose PCV13 vaccine. The highestcarriage rate was observed among children youngerthan 24 months (76.2%). In multivariate analysis,respiratory infection in recent months, age, attendanceat a day-care center and antibiotic usage were notstatistically significant risk factors for carriage. Overall,S. pneumoniae strains were considered as penicillinsusceptible and antimicrobial resistance was limited.Conclusion: We observed a low rate of pneumococcalcarriage in children after PCV13 implementationcompared with that of children receiving PCV7.Although it was reduced, vaccine serotype colonizationin PCV13-vaccinated children remains persistent.