Strptococcal toxic shock syndrome (STSS), a deadly bacterial infection, is spreading over Japan and raising questions regarding its origin and prevention. As of June 2, Japan's National Institute of Infectious Diseases recorded 977 cases, over the 941 total from previous year. This is substantially more than the 395 cases recorded thus far this year in the United States.

The CDC characterizes STSS as a rare but serious infection that might quickly turn fatal. Fever, chills, muscular aches, nausea, and vomiting are among the first signs; limb pain and edema follow. Low blood pressure can occur 24 to 48 hours later and might cause organ failure, higher heart rate, and quick breathing. With a death rate of up to 30%, the CDC emphasizes that STSS can be lethal even under treatment.

Toxins from Streptococcus pyogenes, sometimes known as Group A Streptococcus (GAS), induce STSS and also aggravate sore throats and skin diseases. Expert in infectious illnesses Dr. Céline Gounder notes that severe GAS infections can strike the blood, lungs, and as "flesh-eating" infections with a mortality rate of 30–60%.

Vaccines against influenza and chickenpox are among the preventive actions meant to lower the risk of severe GAS infection. Those near to severe GAS sufferers—especially those who are immunocompromised, pregnant, or have open wounds—should take antibiotics to ward against infection.

Although everyone can have STSS, those most at risk include those over 65, those with skin injuries, and those with medical disorders including diabetes or alcohol use disorder. Other nations including the UK, Ireland, France, the Netherlands, and Sweden have also observed a rise in GAS infections since late 2022. Dr. Gounder underlines the need for worldwide infectious disease surveillance and control.