Serotype distribution and coverage by pneumococcal vaccines in hospitalized adults with pneumococcal pneumonia in Germany

Introduction Understanding the prevalence of pneumococcal serotypes in hospitalized patients with Community-Acquired Pneumonia (CAP) is critical for vaccine development and implementation of future public health policies. Pneumococcal conjugate vaccines (PCVs) have been implemented to decrease the burden of pneumococcal disease. This study aims to identify the serotype distribution of pneumococcal CAP in Germany. Methods This interim analysis of a multicenter, prospective, active observational study, includes patients aged >18 years hospitalized with CAP in 7 German hospitals. Patients were enrolled between August 2022-September 2024. To determine CAP etiology, microbiological tests were performed according to local standard of care. Urinary Antigen Testing for Streptococcus pneumoniae (BinaxNOW) was performed in all patients and two serotype-specific urinary antigen detection (SSUAD) assays were used to detect serotypes in pneumococcal vaccines PCV15 and PCV20. Results S. pneumoniae was detected in 16.5% (85/514) of participants by all diagnostic tests. SSUAD assays detected S. pneumoniae as pathogen in 13.2% (68/514) of participants. In 6 patients, 2 pneumococcal serotypes were detected. The 7 most detected serotypes were: 3, 11A, 8, 23B, 9N, 18C and 22F. Among 74 serotype detections, 64 (86.9%) are included in V116, compared with 56 (75.8%) in PCV20. The difference in coverage between PCV20 and V116 was 10.8% (95% CI: [–3.2%, 24.8%]). Conclusion Among adults hospitalized with CAP in Germany, S. pneumoniae was detected in 13% of cases by SSUAD assays. While the findings suggest that V116 may offer broader serotype coverage compared with PCV20, these differences were not statistically significant.