There has been a concerning rise in syphilis cases despite a drop in the number of Australians tested for sexually transmissible infections during the pandemic, data published by the Kirby Institute on Thursday shows.
In 2021 there were 86,916 diagnoses of chlamydia, 26,577 of gonorrhoea and 5,570 of infectious syphilis in Australia, according to the report titled HIV, Viral Hepatitis and Sexually Transmissible Infections in Australia.
There were reductions in total chlamydia and gonorrhoea diagnoses nationally. But Kirby Institute modelling shows most chlamydia and gonorrhoea cases are undiagnosed and untreated, and the report authors said the decrease in cases is likely a reflection of a drop in the numbers of Australians having a test for sexually transmissible infections (STIs). Chlamydia and gonorrhoea tests are down 14% from pre-pandemic levels.
In contrast syphilis diagnoses increased in 2021, after falling between 2019 and 2020. There have been steady rises in syphilis among gay and bisexual men and among Aboriginal and Torres Strait Islander people, and among women of reproductive age.
In the same time period, there was a large increase in the number of congenital syphilis diagnoses, which occurs when syphilis is transmitted during pregnancy to an unborn child. A disproportionate number of these infections – 60% – occurred among Aboriginal and Torres Strait Islander babies, who make up only approximately 5% of all newborns.
A co-author of the report, Dr Skye McGregor from the University of NSW, said it was a “particularly worrying” trend as pregnant women should be tested regularly for sexually transmitted infections as part of pre and antenatal health screening.
“But Covid-19 has put additional strains on health service delivery and access,” she said. “With timely screening, syphilis can be cured, so even one case of congenital syphilis is completely avoidable and unacceptable.”
Kirby Institute researchers are now working to understand what proportion of pregnant women are not receiving adequate screening, she said.
Diagnoses of genital warts among heterosexuals aged under 21 attending sexual health clinics declined to less than 1% among females and 0% among males under 21 years, reflecting the success of the national HPV vaccination program.
The medical director of Sexual Health Victoria, Dr Kathleen McNamee, said the report reflects what is being seen in clinics.
“Looking at previous years, although the majority of infections are in men, syphilis infections have increased at a greater rate in women,” she said. “Unlike many other STIs, condoms may not be protective.”
She said testing needs to be made easy with time, embarrassment and costs potential barriers. While normal practice is to collect samples for testing from people during their clinic visit, she said many people who had tests ordered after a telehealth consult did not take the extra step of visiting a lab to have their specimens taken.