© Shutterstock

What is streptococcal toxic shock syndrome? -

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).

© Getty Images

Streptococcus pyogenes -

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.

© Getty Images

Strep A -

Strep A can cause sore throats, mainly in children, and many people have it without knowing it, as they may not fall ill.

© Shutterstock

The cause of serious illness -

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).

© Shutterstock

Who is affected? -

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.

© Shutterstock

Fatal statistics -

In the most serious cases, streptococcal toxic shock syndrome can lead to organ failure and necrosis. About 30% of STSS cases are fatal.

© Shutterstock

STSS strikes Japan -

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.

© Shutterstock

Record number of STSS cases -

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).

© Shutterstock

Numbers expected to increase -

Worryingly, the number of cases in 2024 is expected to exceed last year's record numbers, predicted NIID.

© Shutterstock

Unknown factors -

"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.

© Shutterstock

Spreading at an alarming rate -

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.

© Shutterstock

Under fifties at greater risk -

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.

© Shutterstock

Dangerous diagnosis -

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.

© Shutterstock

Why Japan? -

But why exactly is this dangerous infection suddenly so prevalent in Japan? Some health officials think they have an explanation.

© Shutterstock

COVID-19 restrictions lifted -

In May 2023, the Japanese government lifted restrictions imposed during the coronavirus pandemic.

© Getty Images

Class two status -

Beforehand, COVID-19's status was defined as class two, which includes tuberculosis and SARS.

© Getty Images

Reclassified -

The Ministry of Health, Labour and Welfare then reclassified COVID-19's category to class five, placing it on par with seasonal flu.

© Getty Images

Free to roam -

With restrictions lifted, local authorities were no longer able to order infected people to stay away from work or to recommend hospitalization.

© Shutterstock

Complacent attitude -

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.

© Shutterstock

Highly contagious -

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.

© Shutterstock

Methods of infection -

The bacterium can also infect patients through wounds on the hands and feet.

© Getty Images

Possibility of death -

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.

© Shutterstock

The "flesh-eating disease" -

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."

© Shutterstock

What's to blame? -

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.

© Shutterstock

Concerns -

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.

© Getty Images

Vulnerable population -

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.

© Getty Images

Susceptibility to microorganisms -

"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.

© Shutterstock

Practice basic hygiene precautions -

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.

© Shutterstock

Preventative measures urged -

"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)

© Getty Images