From ice to soil
Streptococcal toxic shock syndrome (STSS) is a disease defined as an infection with Streptococcus pyogenes accompanied by the sudden onset of shock, organ failure, and, frequently, death, according to the Centers for Disease Control and Prevention (CDC).
Most cases of STSS are caused by Streptococcus pyogenes. A type of bacteria more commonly known as strep A, it often lives in the nose and throat.
Strep A can cause sore throats, mainly in children, and many people have it without knowing it, as they may not fall ill.
But the highly contagious bacteria responsible for the infection can, in some cases, cause serious illness and other health complications. Pictured is Streptococcus pyogenes bacteria on primary human neutrophil (the most abundant type of granulocytes, or immune cells, and white blood cells in the human body).
Those most affected tend to be adults over 30. Cold-like symptoms are common. But in rare cases, the symptoms can worsen to include strep throat, tonsillitis, pneumonia, and meningitis.
STSS was first reported in Japan in 1992, according to The Japan Times. Since then, notes the newspaper, an average of 100 to 200 confirmed cases have been reported annually.
In 2023, however, Japan recorded 941 cases of STSS. This figure topped the previous record of 894 cases in 2019, according to the National Institute of Infectious Diseases (NIID).
Worryingly, the number of cases in 2024 is expected to exceed last year's record numbers, predicted NIID.
"There are still many unknown factors regarding the mechanisms behind fulminant (severe and sudden) forms of streptococcus, and we are not at the stage where we can explain them," said NIID in a statement.
While senior citizens have always been at greater risk of the group A strain, authorities in Japan are reporting more deaths among patients under 50, according to NIID.
Meanwhile, STSS continues to spread across Japan at an alarming rate. In the first two months of 2024, 378 cases were recorded, with infections identified in all but two of Japan's 47 prefectures, reports The Guardian.
But why exactly is this dangerous infection suddenly so prevalent in Japan? Some health officials think they have an explanation.
In May 2023, the Japanese government lifted restrictions imposed during the coronavirus pandemic.
The Ministry of Health, Labour and Welfare then reclassified COVID-19's category to class five, placing it on par with seasonal flu.
Beforehand, COVID-19's status was defined as class two, which includes tuberculosis and SARS.
With restrictions lifted, local authorities were no longer able to order infected people to stay away from work or to recommend hospitalization.
Furthermore, the move prompted complacency. Where once the wearing of a mask was mandatory by law and compliance with health regulations strictly adhered to, after May 2023 many chose to relax their guard. Even the "Three Cs" were largely ignored—avoiding closed spaces, crowded places, and close-contact settings.
Most people with strep infection do not develop symptoms. But in rare instances where the bacterium reaches the bloodstream, muscles and lungs, the symptoms can quickly turn serious, causing low blood pressure, multiple organ failure, and even death, authorities say.
Immediate treatment involves the administration of antibiotics. But serious complications require the removal of the infected tissue. It's why streptococcal toxic shock syndrome is sometimes dubbed the "flesh-eating disease."
Reacting to the crisis, Keizo Takemi, Japan's health minister, told reporters that, while the exact cause behind the increase is unknown, it is probably related to the rebound of respiratory diseases after Japan entered a post-pandemic phase last spring.
Ken Kikuchi, a professor of infectious diseases at Tokyo Women's Medical University, agrees. Speaking to The Guardian, he expressed concern about the exponential rise in cases this year in the number of patients with severe invasive streptococcal infections. He's also of the opinion that the reclassification of COVID-19 was the most important factor behind the increase in streptococcus pyogenes infections.
Professor Kikuchi believes that over 50% of the Japanese have been infected by SARS-CoV-2, the virus that causes COVID-19. These same people are especially vulnerable to STSS.
Streptococcal bacterium are highly contagious. And just like those of COVID-19, infections are spread by droplets, for example through coughing or sneezing, and physical contact.
The bacterium can also infect patients through wounds on the hands and feet.
As it battles more cases of the tissue-damaging bacterial disease, the Japanese government is urging its citizens to take the same basic hygiene precautions against strep A that became a part of everyday life during the coronavirus pandemic.
"We want people to take preventative steps such as keeping your fingers and hands clean, and exercising cough etiquette," said Keizo Takemi, stressing that proper hygiene is important.
Sources: (CDC) (MedlinePlus) (The Japan Times) (NIID) (The Guardian) (Ministry of Health, Labour and Welfare) (JapanGov)
A record number of cases involving a rare but serious type of bacterial infection is currently spreading across Japan. Known as streptococcal toxic shock syndrome (STSS), its prevalence is alarming health officials, given its 30% mortality rate. But as cases of this highly contagious condition soar, the Japanese Ministry of Health, Labour and Welfare is still struggling to identity the exact cause of what some have dubbed the "flesh-eating disease." But what exactly is STSS, and why is it so feared?
Click through and learn more about this potentially deadly infection sweeping across Japan.
In the most serious cases, streptococcal toxic shock syndrome can lead to organ failure and necrosis. About 30% of STSS cases are fatal.
In fact, of the 65 people under 50 who were diagnosed with STSS between July and December in 2023, about a third, or 21, died, reports the Osaka-based Asahi Shimbun newspaper.
"People's immunological status after recovering from COVID-19 might alter their susceptibility to some microorganisms. We need to clarify the infection cycle of severe invasive streptococcal pyogenes diseases and get them under control immediately," Kikuchi told The Guardian.
What is streptococcal toxic shock syndrome, and why is Japan worried?
Japanese health officials are increasingly concerned about this rare but serious type of bacterial disease
HEALTH Stss
A record number of cases involving a rare but serious type of bacterial infection is currently spreading across Japan. Known as streptococcal toxic shock syndrome (STSS), its prevalence is alarming health officials, given its 30% mortality rate. But as cases of this highly contagious condition soar, the Japanese Ministry of Health, Labour and Welfare is still struggling to identity the exact cause of what some have dubbed the "flesh-eating disease." But what exactly is STSS, and why is it so feared?
Click through and learn more about this potentially deadly infection sweeping across Japan.