Prevalence of Streptococcus pneumoniae serotypes causing pneumococcal diseases in the Chinese Mainland: A systematic review and meta-analysis

Pneumococcal disease (PD) caused by Streptococcus pneumoniae (Sp) continues to be a global public health concern. Monitoring the prevalence and shift of Sp serotypes causing PD is critical for vaccination and local policies for PD management. A systematic review of published work on pneumococcal serotype distribution in the Chinese Mainland from January 1997 to July 2023 was conducted. The literature was searched in Medline, Embase, the Cochrane Library, Web of Science, CNKI, and Wanfang. Distribution of the Sp serogroups/serotypes was presented as count and proportion. Pooled distributions were calculated using a double arcsine transformation. Subgroup analyses were performed according to isolate location, strain source, patient age, period, and clinical manifestation. In total 36,477 Sp isolates in 159 studies were included. In the Chinese Mainland, the highest proportion of Sp in PD was serotype 19F, followed by 19A, 23F, 14 and 6B. Serotype 19F was the most predominant circulating serotype through all time periods. PD cases caused by non-vaccine serotypes showed a significant increase after 2019. In summary, from 1997 to 2023, the top 10 prevalent Sp serotypes causing PD in the Chinese Mainland were 19F, 19A, 6, 23F, 14, 6B, 6A, 3, 15B, and 9 V. Although the distribution of serotypes varied according to the subgroups, the increase in non-vaccine serotypes (e.g. 15A), and diversity distribution of serotypes 6A and 3 in different age groups should not be ignored. Streptococcus pneumoniae is a type of bacteria that commonly causes disease. It is widespread in many areas of the world, including the Chinese Mainland. To effectively control the spread of streptococcus pneumoniae,policy makers and healthcare providers need to know what serotypes of the bacteria are present. This systematic review analyzed the literature from the last 25 years about the serotype distribution of streptococcus pneumoniae in the Chinese Mainland. The review also checked to see if the serotype distribution changed as a list of factors changed. This review found that the serotype distribution of streptococcus pneumoniaechanges according to location, strain source, patient age, time period, and clinical manifestation. The changes that happened over time suggest that the serotypes of streptococcus pneumoniaethat are not covered by commonly used vaccines have become more common over time. However, even though they became more common, the vaccine types remain covering the predominant s