There has been an alarming surge in the number of cases of streptococcal toxic shock syndrome (STSS), often referred to as a "flesh-eating" bacterial infection, in Japan, particularly in the capital city of Tokyo. Since January this year, a staggering 977 cases of STSS were reported in the country, overshadowing the previous record of 941 infections reported in 2023, data from the National Institute of Infectious Diseases revealed.

What causes STSS?

STSS is caused by Group A Streptococcus (GAS), a common bacterium known for causing ailments like skin infections and strep throat. "This condition is triggered by an unusual manifestation of strep A bacteria, which can become invasive, penetrating deep into soft tissues and causing necrotising fasciitis," Professor Jon Cohen, Emeritus Professor of Infectious Diseases at Brighton and Sussex Medical School, told The Telegraph.

Could STSS be fatal? 

In severe cases, it can lead to rapid deterioration of health, including swelling and severe limb pain, fever, and potentially fatal complications such as necrosis, organ failure, and septic shock. 

Is there a vulnerable age-group?

The elderly, aged 50 and above, are particularly vulnerable to the disease. The surge in cases has been most pronounced in Tokyo, where 145 cases were reported in the first half of 2024. Adults over 30 years old constitute the majority of patients affected, with a mortality rate hovering around 30 per cent, Japanese daily Asahi Shimbun reported.

What are the experts saying?

Experts suggest that the resurgence of STSS in Japan could be linked to the easing of social restrictions during the COVID-19 pandemic, similar to trends observed in Europe. "In England and elsewhere, the relaxation of social restrictions led to a rebound in strep A infections among susceptible populations, particularly children," Professor Shiranee Sriskandan, a professor of infectious diseases at Imperial College London, told The Telegraph.

She added, "It's plausible that Japan is now experiencing a delayed rebound in cases due to similar dynamics, exacerbated by seasonal factors." Meanwhile, health authorities in Japan have intensified efforts to contain the outbreak. Officials have been reaching out to people, re-emphasising early diagnosis and prompt treatment with antibiotics as crucial measures to mitigate the impact of the epidemic.