Before and after the bottleneck: pediatric group A streptococcal infections in Houston, TX, from 2013 to 2023

Group A <i>Streptococcus</i> (GAS) causes common childhood infections such as strep throat but can also lead to severe, life-threatening disease. During and after the COVID-19 pandemic, many regions reported sharp increases in GAS infections, yet the reasons for these changes were unclear. Using long-term surveillance of children in a large US city, this study shows that the post-pandemic rise in GAS was accompanied by meaningful changes in both the types of infections and the strains causing them. We found a small but significant increase in invasive disease, shifts in the most common GAS strain types, and temporary increases in resistance to certain antibiotics. These changes likely reflect how pandemic-related disruptions altered bacterial spread. By examining both mild and severe infections over more than a decade, this work demonstrates how large-scale changes in human behavior can reshape bacterial disease patterns and highlights the importance of continued monitoring to protect child health.