Monitoring Over a Decade in the Serotype Prevalence of Streptococcus pneumoniae in Iran: A Systematic Review and Meta-analysis

Background: There is no comprehensive information about the circulating serotypes of Streptococcus pneumoniae in Iran in recent years. This study aimed to summarize information about the changes over a decade in the serotype prevalence of S. pneumoniae in Iran. Methods: We performed a comprehensive search in PubMed/Medline, Web of Science, Science Direct, and the Iranian Database, such as Magiran and SID, from January 2011 to February 2023. The systematic process, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), was carried out by two researchers who were both independent and calibrated. Statistical analyses were carried out using Comprehensive Meta-Analysis software. Identifying and measuring heterogeneity were done using I² and the chi-square test. Finally, Begg's rank correlation test was used in combination with a funnel plot to evaluate any possible publication bias. Results: The search returned 16 relevant results, with a total of 1575 isolates. Of those studies, eight studies reported the distribution of S. pneumoniae serotypes among patients, three studies among healthy individuals, and five studies among both groups. As the meta-analysis revealed, the most common serotypes were 23F (n = 299, 14.1% [95% CI: 9.7-19.9]; I² = 84.3%; P<0.001 for heterogeneity), 19F (n = 221, 13.4% [95% CI: 9.9-17.9; I² = 76.7%; P<0.001 for heterogeneity]), and 19A (n = 102, 8.7% [95% CI: 6.5-11.7; I² = 54.3%; P<0.001 for heterogeneity]). Moreover, Begg's test (P = 0.160, 0.173, and 0.176 for 23F, 19F, and 19A, respectively) showed no evidence of publication bias. Conclusion: Based on our pooled results, the majority of the serotypes of pneumococci in the Iranian population were 23F, 19F, and 19A, respectively, over the last decade. The findings can be valuable in selecting effective pneumococcal vaccine candidates and targeted antibiotics in Iranian patients.