[Research and development progress of pneumococcal conjugate vaccines based on the serotype distribution...

Streptococcus pneumoniae (Spn) is one of the major pathogens responsible for morbidity and mortality worldwide, and pneumococcal diseases constitute a significant global public health burden, with a particularly high burden among children under five years of age and older adults. Based on differences in the structure of capsular polysaccharides, more than 100 pneumococcal serotypes have been identified to date. The pathogenicity of Spn is, to some extent, associated with immune evasion mediated by serotype-specific capsular polysaccharides; therefore, pneumococcal vaccines covering multiple serotypes have significant public health importance for the prevention and control of related diseases. With the promotion and application of pneumococcal vaccines in China, the serotype distribution of Spn has undergone dynamic changes, and serotype-specific epidemiological evidence as well as real-world evidence on vaccine use has continued to accumulate. This study systematically reviews the distribution characteristics of Spn serotypes and related diseases in China, as well as the current status of antimicrobial resistance; describes the immune protective mechanisms of pneumococcal conjugate vaccines (PCVs) against different serotypes; compares the immunogenicity and protective effects of PCVs with different valences; and discusses the development directions and key scientific issues of higher-valent PCVs and universal pneumococcal vaccines, in order to provide evidence reference and scientific support for the design of PCV serotype coverage and the optimization of immunization strategies in China.