A deadly bacterial infection is spreading in Japan. Here's what to know about causes and prevention.

A potentially deadly bacterial infection called streptococcal toxic shock syndrome, or STSS, is spreading in Japan, prompting questions about what causes it and how to prevent it. 

Japan's National Institute of Infectious Diseases issued a statement in March warning that STSS was increasing in the country. As of June 2, Japan's health ministry reports 977 cases since the start of 2024 — surpassing last year's 941 cases.

That's almost two and a half times the number reported in the U.S. so far this year.