The Recent Rise of Streptococcus Pyogenes Group A–Related Deaths in Cook County

Group A Streptococcus (GAS) is a gram-positive bacterium that causes a spectrum of illnesses, ranging from mild infections such as pharyngitis and impetigo to severe invasive diseases, including necrotizing fasciitis, streptococcal toxic shock syndrome, sepsis, and septic shock. Surveillance data from the United States and Europe indicate a marked post-COVID-19 pandemic increase in invasive GAS infections. At the Cook County Medical Examiner's Office (CCMEO), a retrospective review (2015-2025) identified 26 fatal GAS cases, with a significant surge in the postpandemic period. Postmortem diagnosis relies on cultures from sterile sites and histologic examination to confirm infection and minimize contamination artifacts. Most cases demonstrated rapid clinical progression, underscoring the high lethality of invasive GAS. As a secondary objective, postmortem pharyngeal swabs were collected in pediatric cases with suspected GAS infection and tested using a rapid antigen assay; all results were negative and confirmed by culture. These findings suggest the test may be useful for ruling out infection in negative cases, though the sensitivity in confirmed positives remains undetermined. This study highlights the essential role of forensic pathologists in detecting and documenting invasive GAS infections, thereby supporting public health surveillance, outbreak monitoring, and preventive strategies. Prompt recognition, accurate diagnostic sampling, and sustained vigilance are critical to reducing morbidity and mortality from this pathogen.