In 2017, Poland introduced the 10-valent pneumococcal conjugate vaccine (PCV) into its national immunization schedule. This prospective study was conducted between March and June 2020 to determine the impact of vaccination on prevalence of the nasopharyngeal carriage of S. pneumoniae in 176 healthy children and to determine how conjugate vaccines indirectly affect colonization of nasopharyngeal microbiota. Pneumococcal isolates were analyzed by serotyping and antimicrobial resistance tests. Nasopharyngeal microbiota were detected and identified using the culture method and real-time PCR amplification primers and hydrolysis-probe detection with the 16S rRNA gene as the target. In the vaccinated group of children, colonization was in 24.2% of children, compared to 21.4% in the unvaccinated group. Serotypes 23A and 23B constituted 41.5% of the isolates. Serotypes belonging to PCV10 and PCV13 constituted 4.9% and 17.1% of the isolates, respectively. S. pneumoniae isolates were resistant to penicillin (34.1%), erythromycin (31.7%), and co-trimoxazole (26.8%). Microbial DNA qPCR array correlated to increased amounts of Streptococcus mitis and S. sanguinis in vaccinated children, with reduced amounts of C. pseudodiphtericum, S. aureus, and M. catarrhalis. Introduction of PCV for routine infant immunization was associated with significant reductions in nasopharyngeal carriage of PCV serotypes and resistant strains amongst vaccine serotypes, yet carriage of non-PCV serotypes increased modestly, particularly serotype 23B.

Introduction: Tympanic membrane perforation (TMP) may be caused by several factors but commonly leads to conductive hearing loss. This study aims to characterize the profiles of hearing loss in pediatric patients with TMPs. Material and methods:A retrospective analysis of the medical charts of 27 patients was conducted. Otoscopy of the TM was done and pure tone audiometry was used to assess hearing loss. Cluster analysis was applied to evaluate the profiles of hearing loss and to find possible relations between profiles of hearing loss and the location of the perforation on the TM.Results: Cluster analysis revealed three types of hearing loss. The mean hearing loss in cluster 1 (6 cases) was above 30 dB, mainly as the result of perforation after chronic otitis media. Hearing loss in clusters 2 (9 cases) and 3 (12 cases) was less than 30 dB. In cluster 2 the perforation was mostly located in the posterior quadrants, while in cluster 3 it was most commonly in the inferior quadrants. In clusters 2 and 3, perforation was usually caused by slap of the open hand, injury, or past ventilation tube.Conclusions: Three different profiles (clusters) of hearing loss resulting from TMP were identified. Force of injury, etiology of the injury, and inflammation produce different sizes of perforations. Conductive hearing loss increases with perforation size and is independent of TM location. In general, hearing loss classification methods have the potential to improve diagnostic procedures, surgery, and rehabilitation of patients with TMPs.