Epidemiology of Pediatric Invasive Group A Streptococcal Infections in 10 US States, 2004-2023.

BACKGROUND

Group A Streptococcus (GAS) infections are common in children, ranging from mild to life-threatening invasive disease. Large-scale descriptions of changes in pediatric invasive GAS infections in the United States, particularly during the coronavirus disease 2019 (COVID-19) pandemic, are limited.

METHODS

We used the Centers for Disease Control and Prevention's (CDC's) Active Bacterial Core surveillance (ABCs), a multistate, population- and laboratory-based surveillance system, to assess changes in pediatric (<18 years old) invasive GAS incidence, clinical presentation, and bacterial strain characteristics from 2004 to 2023. Interrupted time series analysis was used to compare observed versus expected GAS incidence during 2020-2023, informed by trends before the COVID-19 pandemic (2004-2019).

RESULTS

During 2004-2023, 2856 invasive GAS cases were identified. Incidence remained stable from 2004 to 2019 (mean incidence 1.9 per 100 000), decreased in 2020 (1.0) and 2021 (0.6), and rebounded in 2022 (1.5) and 2023 (4.4). ICU admission increased from 2011 to 2023; case fatality remained stable. Penicillin resistance was not detected. Clindamycin non-susceptibility doubled from 2011 (3.8%) to 2022 (7.5%), before slightly decreasing in 2023 (6.4%). Infections due to emm1, the most frequently identified emm type in children with severe disease, almost disappeared in 2021 but surged in late 2022.

CONCLUSIONS

After remaining stable for more than a decade, pediatric invasive GAS incidence declined during the COVID-19 pandemic and rebounded in 2022, more than doubling 2004-2019 incidence in 2023. Although case fatality remained low, intensive care unit (ICU) admissions increased over time, highlighting the need for effective preventive measures such as vaccines. Increasing clindamycin non-susceptibility bears continued monitoring.