Recent news has highlighted an alarming situation in Japan, where cases of serious and highly fatal bacterial infections have reached record levels. Official figures from the Japanese Ministry of Health indicate that 977 cases of streptococcal toxic shock syndrome (STSS) were recorded until June 2. With a mortality rate of up to 30%, this infection has already caused the death of 77 people between January and March, according to the most recent statistics available.
This steady rise in STSS cases in Japan has surpassed the previous year’s record, with 941 preliminary infections, the highest figure since statistics began in 1999. In 2022, the Japanese National Institute of Infectious Diseases reported 97 deaths from STSS, the second highest number of deaths in the last six years.
Strep toxic shock syndrome is a rare but serious bacterial infection that can develop when bacteria spread into deep tissues and the bloodstream. Patients initially present with fever, muscle pain and vomiting, but symptoms can quickly become life-threatening with low blood pressure, swelling and multiple organ failure leading to shock.
Even with treatment, STSS can be fatal. According to the U.S. Centers for Disease Control and Prevention (CDC), out of every 10 people with STSS, up to three people could die from the infection.
Most cases of STSS are caused by the group A streptococcal (GAS) bacteria, which primarily causes fever and throat infections in children. In rare circumstances, Strep A can become invasive when the bacteria produce a toxin that allows it to enter the bloodstream, causing serious illnesses such as toxic shock.
Strep A can also cause “flesh-eating” necrotizing fasciitis, which can lead to loss of limbs. However, most patients with this disease had other risk factors for infection, such as cancer or diabetes, according to the CDC.
Invasive Strep A infections have largely been brought under control thanks to Covid-19 control measures, such as mask wearing and social distancing. However, after these measures were relaxed, many countries reported a surge in cases.
As of December 2022, five European countries reported to the World Health Organization an increase in invasive group A streptococcus infections, with children under 10 years of age most affected. The CDC also said it was investigating an apparent increase in illness at that time.
In March, Japanese authorities warned of a surge in STSS cases. Japan’s National Institute of Infectious Diseases released a risk assessment stating that the number of cases of STSS caused by invasive Group A Strep “has increased since July 2023, especially among people under 50 years old.”
Older people with an open wound are at higher risk of contracting STSS, including those who have recently had surgery, the CDC said on its website.
However, experts don’t know how the bacteria got into the body for nearly half of people with STSS, the CDC added.
The reason for the rise in STSS cases this year in Japan remains unclear, according to Japanese public broadcaster NHK. Professor Ken Kikuchi, from Tokyo Women’s Medical University, suggested the increase could be due to people’s weakened immune systems following the Covid-19 pandemic.
“In a setting where individuals are constantly exposed to bacteria, immunity can be boosted. However, this mechanism was absent during the coronavirus pandemic,” Kikuchi said. “So more people are now likely to be infected, which could be a reason for the sharp increase in cases.”
This alarming situation highlights the importance of remaining vigilant against serious bacterial infections and maintaining adequate precautionary measures to protect public health.