Outbreak of severe community-acquired bacterial infections fromStreptococcus pyogenes, Streptococcus pneumoniae, Neisseria meningitidis, andHaemophilus influenzaeamong children in North Rhine-Westphalia (Germany), October to December 2022

Abstract

Background: In late 2022, a surge of severe bacterial infections caused by S. pyogenes was reported in several European countries, including Germany. This study assessed disease burden and severity of hospitalizations for community-acquired bacterial infections with S. pyogenes, S. pneumoniae, N. meningitidis, and H. influenzae among children in North Rhine-Westphalia (NRW), Germany, during the last quarter of 2022 compared to long-term incidences. Methods: Hospital cases due to bacterial infections between October and December 2022 were collected from 59/62 (95 %) children's hospitals in NRW and combined with surveillance data (2016 - 2023) from the national reference laboratories for streptococci, N. meningitidis, and H. influenzae. Total cases in NRW and incidence rates from January 2016 to March 2023 were estimated by capture-recapture analyses. Expected annual deaths from the studied pathogens were calculated from national death cause statistics. Results: Between October and December 2022, 153 cases with high overall disease severity were reported with pneumonia being most common (59 %, n = 91). Incidence rates of bacterial infections declined at the beginning of the COVID-19 pandemic. In late 2022 and early 2023 a massive surge to levels unprecedented since 2016 was observed, mainly driven by S. pyogenes and S. pneumoniae. Observed deaths during the study period exceeded the expected number for the entire year in NRW by far (7 vs. 0.9). Discussion: The unprecedented peak of bacterial infections in late 2022 and early 2023 was caused by various mechanisms intertwined that require close surveillance and improved precautionary measures for future outbreaks.