A rare and dangerous bacterial infection is spreading at a record pace in Japan, with authorities struggling to identify the cause. This was reported by local health authorities, cited by the Guardian. The number of cases in 2024 is expected to surpass last year's record figures, and there is growing concern that the most serious and potentially deadly form of group A streptococcal disease – streptococcal toxic shock syndrome (STSS) – will continue to spread, due to the presence of highly virulent and infectious strains of bacteria.
The National Institute of Infectious Diseases (NIID) said: “There are still many unknown factors regarding the mechanisms underlying fulminant (severe and sudden) forms of strep, and we are unable to explain them at this stage.”
According to provisional data released by the NIID, 941 cases of STSS were reported last year. In the first two months of 2024, 378 cases have already been recorded, with infections identified in all but two of Japan's 47 prefectures. Older people are considered at greatest risk, but the group A strain is causing more deaths among patients under 50, according to the NIID. Of the 65 people under 50 diagnosed with STSS between July and December in 2023, about a third, or 21, have died, the Asahi Shimbun newspaper reported. The highly contagious bacteria that cause the infection can, in some cases, cause serious illness, health complications and death, particularly in adults over the age of 30. About 30% of STSS cases are fatal.