[Three Suspected Cases of Streptococcal Toxic Shock Syndrome in the Republic of Korea, 2000-2024.3]

Streptococcal toxic shock syndrome (STSS) is a serious disease caused by invasive group A Streptococcus (GAS) infection. Since the end of 2022, the incidence of scarlet fever and invasive group A Streptococcus (iGAS) has increased in Europe, the USA, and Canada. In March 2024, Japan reported 941 cases of STSS in 2023, which is the highest number of cases since the start of surveillance in 1999. In the Republic of Korea (ROK), scarlet fever, which can be caused by GAS infection, has been designated and managed as a second-class, legally communicable disease. In addition, using the Acute Respiratory Infection Network (AriNet) for sample medical institutions, we have been investigating the status of the epidemic and the characteristics of GAS. The number of scarlet fever cases in the ROK in 2023 was 810, which is a slight increase in numbers from during to after the coronavirus disease 2019 (COVID-19) pandemic but low compared with the numbers before the COVID-19 pandemic. In addition, no increase in GAS numbers was observed using AriNet. Three of the reported cases of scarlet fever since 2000 were suspected STSS cases. In all three cases, rapid hypotension and clinical symptoms, such as renal dysfunction, blood coagulation disorder, and multiple organ failure, were confirmed. Culture tests confirmed GAS. In the third suspected case of STSS, coinfections with influenza and GAS were identified. The Korea Disease Control and Prevention Agency will continue to monitor changes in the incidence of streptococcal infections in the ROK by comprehensively strengthening monitoring by establishing an iGAS monitoring system.