The summary

• Japan has reported a record number of cases of streptococcal toxic shock syndrome, a rare and dangerous bacterial infection caused by Group A strep bacteria.
• The U.S. similarly saw serious Group A strep infections — including STSS — reach a 20-year high in 2023.
• Experts think a post-pandemic rebound of bacterial and viral infections could partially explain the trend, but many unanswered questions persist.