Increasing incidence of the complicated pneumonia caused by Streptococcus pyogenes in children – another post-Covid epidemiological challenge?

Following the Covid-19 pandemics, we’ve been observing changes in the epidemiology of respiratory infections caused by different pathogens including S. pyogenes (GAS). Therefore we AIMED to investigate the incidence of community acquired complicated pneumonia (CACP) in children in the Wielkopolska region with a special emphasis on the disease caused by GAS. <bold>Methods:</bold> Retrospective analysis of the medical records of the children hospitalised from 2018 to 2023 with CCAP complicated by pleural effusion/empyema (PE), lung abscess or necrotizing pneumonia. <bold>Results:</bold> Number of children hospitalized due to CAP ranged from 1026 to 1218 cases per year, with a significant decrease in 2020/2021. From 2018 to 2022, there were several cases of CCAP per year, and GAS was rarely confirmed. In 2022/2023 a 4-fold increase in the incidence of CCAP was observed (60 vs. 16 cases), accompanied by increased GAS isolation (Figure 1). In 2022/2023 CCAP accounted for 5.7% of all pneumonia cases. In 14 children (23.3% of CCAP) GAS infection was confirmed - 12 with PE, 1 with lung abscess, and 1 with necrotizing pneumonia. 86% of these children had no underlying condition, nevertheless their clinical course was severe: 43% required intensive care and 2 died. <fig><object-id>erj;64/suppl_68/PA1390/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig> <bold>Conclusions:</bold> GAS is an increasingly important cause of CCAP in children and this changing epidemiological trend seems worth reporting.