What we know about the “flesh-eating” bacteria that worries Japan

Since January, the Japanese archipelago has registered a record number of group A streptococcal infections, with nearly a third of cases being fatal.

Japanese authorities tried to allay fears during a press briefing by a government spokesman on Friday. But there is growing concern at home and abroad as the number of cases of streptococcal infection has increased in the year 2023 and even more since the beginning of the year.

The government of the capital, Tokyo, warned residents about the strong spread of the bacteria, reported Sunday, March 24. The Japan Times. In terms of serious health concerns, after the 2026 World Cup qualifying match between Japan and North Korea was canceled by FIFA on Saturday, enough to revive fears. Here’s what we know about it.

“Flesh-eating” bacteria, with severe but rare complications

Group A Streptococcus (GAS) bacteria are human pathogens that are transmitted through the air (droplets) or direct contact (nasal secretions, skin lesions). According to data from Public Health France (PDF document)In 80% of cases it causes benign infections, such as angina, impetigo or skin lesions.

More rarely, it can cause dermohypodermatitis or necrotizing fasciitis (a disease). “resulting in complete destruction of the soft tissues”, which earned him the nickname of flesh-eating bacteria, recalls Sainte Public France), or streptococcal toxic shock syndrome (SCTS). These two acute complications are rare, but can be fatal.

SCTS releases toxins that can lead to organ failure. The first symptoms are sore throat, fever, diarrhea, vomiting and lethargy. It is fatal in 40% of cases, according to Sainte-Publique France, and in one in three cases, according to the American Centers for Disease Control and Prevention. Dermohypodermatitis or necrotizing fasciitis is fatal in 20 to 45% of cases, according to Sainte-Publique France.

An outbreak of cases in Japan

A significant increase in the number of SCTS has been reported in the Japanese archipelago. According to the National Institute of Infectious Diseases in Japan, in less than three months from January 1 to March 13, 2024, 474 cases of the syndrome were reported. This is more than half of all SCTS cases reported in the country during 2023 (941), a record year, as a Japanese newspaper headlined on January 18. Asahi Shimbun. The elderly are considered to be at greater risk, but deaths are increasing among patients under 50, notes the institute, which reports 21 deaths in this age group in 2023, a third of the death rate.

This outbreak of cases made headlines in newspapers around the world, to the point that the Japanese government sought to put concerns into perspective on Friday, especially after North Korea refused to host the national football team. On Thursday, Pyongyang signaled it did not want to host the match between their two teams, which qualified for the 2026 World Cup, and was initially scheduled for March 26. Finally, FIFA announced the cancellation of the match on Saturday.

Worry is spreading across the Asian continent: On Friday, the South Korean Disease Control and Prevention Agency warned travelers from Japan of the risk of SCTS, underlining The Japan Times.

Japanese government spokesman Yoshimasa Hayashi declined to comment on Pyongyang’s surprise move on Friday, but stressed that Japan is not the only country affected by the SCTS. Since the end of the Kovid-19 pandemic, “The number of patients with respiratory tract infections has increased in various countries, including Japan”., he announced during his regular press briefing. But there is still uncertainty about the cause of the outbreak of cases, as Japan’s health minister admitted to the press on January 22, reports The Japan Times.

An increase in cases has also been reported in France

Waves of invasive group A Streptococcus infections were also observed in 2022–2023 in Europe, including France, North America and Australia.

In France, a March 2023 Public Health France report noted an increase in invasive group A streptococcal infections in children and adults. Among people over the age of 18, the number of cases observed between October and December 2022 was significantly higher than the previous four years of reports. The frequency of infection cases associated with SCTS was increasing, increasing from 16.5% in the period 2017-2021 to 21% in December 2022, the institute further noted.

Experts talk about reduced immunity after covid

Health authorities are closely monitoring the situation, but they also recognize that the mechanism of SCTS is still unknown to medicine. While awaiting scientific progress, Japan’s health minister in January called on the population to continue using preventive measures, such as washing hands regularly and wearing masks in busy public places.

Some medical experts speculate that this outbreak of bacterial infections is due to a decline in collective immunity after a Covid-19 episode. “During the pandemic, the circulation of infectious diseases was slowed by health measures put in place around the world,” Masahiro Kami, a doctor and president of the Medical Governance Research Center, explains on the Toyo Keizai site. “This has reduced the number of people with immune defenses, leading to an increase in infections in recent times.”

In a British daily The Guardian, Ken Kikuchi, professor of infectious diseases at Tokyo Women’s Medical University, points to an additional factor. “In my opinion, more than 50% of Japanese people have been infected with SARS-CoV-2. The immune status of people who have recovered from Covid-19 may improve their susceptibility for certain. micro-organisms”He believes.