Researchers at the Peter Doherty Institute for Infection and Immunity have studied infections of Streptococcus dysgalactiae subspecies equisimilis (SDSE), a close cousin of group A strep, and found it’s rising at markedly different rates across parts of the country.

Both infections cause skin and soft tissue infections and, in severe cases, can invade the blood and organs and become life-threatening.

Lead author Dr Ouli Xie from the University of Melbourne said SDSE had previously been considered a “minor player” compared to group A strep, but the study proved it was causing “a significant and rising burden of severe disease in Australia”.

He said in the remote northern regions, cases were 25 per cent higher than in the south-east.

Further to this, the study found that within the Top End, Indigenous Australians were three times more likely to develop the invasive disease than non-Indigenous people.

“We urgently need strategies that address the social determinants of health driving this burden, as well as new approaches to prevent and treat invasive strep infections,” Doherty Institute researcher and co-lead author Professor Steven Tong said.

The study also found that some treatments used to control the spread of group A strep infections, such as antibiotics, were not as effective with SDSE.