Sweden reports most invasive group A streptococci cases since it became notifiable 20 years ago
The Swedish Public Health Agency reports a total of 1,327 invasive group A streptococci, iGAS cases in 2023, including 141 children aged 0–9, which is the highest number since iGAS became notifiable in 2004.
In 2022, Sweden saw 374 iGAS cases.
The counties/regions reporting the most cases include Stockholm (364), Västra Götaland (201) and Skåne (186).
According to health officials:
A contributing cause is likely increased contacts and lower immunity in the population after the restrictions during the pandemic years 2020–2022. The fact that we are seeing a large spread of other respiratory infections such as covid-19, influenza and the RS virus may also have contributed to the increase, because simultaneous infection of viruses and group A streptococcus can increase the risk of invasive disease, says state epidemiologist Magnus Gisslén.
In recent years, the spread of variants of group A streptococci associated with an increased incidence of cases with iGAS has become more common in Europe and Sweden. The Public Health Agency has, in collaboration with the regions, analyzed some of the cases with mapping (whole genome sequencing) of the bacteria's genetic material. The analysis showed that the cases did not differ genetically.
Group A Streptococcus (GAS) bacteria can cause a range of illnesses, from pharyngitis (i.e., strep throat) and skin and soft tissue infections to uncommon but severe diseases such as sepsis, streptococcal toxic shock syndrome, and necrotizing fasciitis. These severe and invasive diseases are associated with high mortality rates and require immediate treatment, including appropriate antibiotic therapy.