In the past decade, the number of syphilis cases across Australia has more than doubled, and syphilis was declared a Communicable Disease Incident of National Significance in August 2025.

But 10 months on, there are signs that the outbreak is starting to ebb. In 2024, there were 5866 cases — more than double the number of cases in 2014. Cases rose to 8993 in 2025 — the highest number on record since the disease became notifiable in 2004. So far this year, there have been more than 2800 new cases of syphilis notifications across the country.

Melbourne Sexual Health Centre sees one third of Victoria’s syphilis cases, according to Director Jason Ong, MBBS, PhD, who also is a professor of medicine at Monash University in Melbourne, Australia. “Data from Victoria show that there’s been a slight plateau, which is great to see. It might be a signal that the tide is starting to turn. We’ll have to see what happens for the rest of the year,” he told Medscape News Australia.

The sharp rise in cases was driven by several factors, he explained, including a decrease in the use of condoms due to decreased fear of HIV, online dating apps, international travel, and the frequently asymptomatic nature of the disease. Of greatest concern were the huge increase in cases among women of reproductive age and the rise in congenital syphilis cases and infant deaths.

“The biggest driver is that people are not testing frequently enough,” said Ong. “There are certain sexual networks not testing for syphilis, but there’s a high incidence of syphilis transmission across networks. These are the people who don’t come to us: the people who aren’t engaged with healthcare and who don’t engage with community messages.”

Discussing Safer Sex

Earlier this year, in a bid to equip general practitioners with the tools and confidence for the prompt detection and testing of the disease, a new campaign was launched, Stop Syphilis, by the Australasia Society for HIV, Viral Hepatitis, and Sexual Health Medicine (ASHM), the country’s peak organization for healthcare workers who focus on HIV, bloodborne viruses, and sexual and reproductive health.

This campaign follows an ASHM survey that found that more than half of healthcare providers don’t feel confident about when to test or refer for syphilis. About 38% believed it’s their responsibility to raise sexual health with their patients. The campaign provides several resources, including a clinical indicator tool, management guidelines, and a decision-making tool that encourages professionals to move from risk-based testing to opportunistic and enhanced testing strategies.

Promoting ASHM resources is crucial to tackling the epidemic and supporting general practitioners, Sara Whitburn, MBBS, medical director of Sexual Health Victoria and chair in the Sexual Health Special Interest Group of the Royal Australian College of General Practitioners in Melbourne, Australia, told Medscape News Australia.

“I encourage general practitioners to get familiar with the ASHM guides, to be aware that benzathine benzylpenicillin is the specific penicillin required for treatment and that it can be supplied via doctors’ bag prescription, and to connect with local sexual health teams for support and advice to support testing and treating in primary care,” she said.

“We also need to continue discussing safer sex. Quality sexual health education is crucial. We need increased government support and funding for sexual health training and for increased rebates for health professionals to provide longer consultations.”

In the past, general practitioners used to think that heterosexuals were not at risk for syphilis, so they didn’t consider testing for it, said Ong. Now clinicians are more aware that syphilis affects the heterosexual population.

“That said, general practitioners still find it uncomfortable to talk about sex or raise it with their patients,” he said. “General practitioners do health checks all the time. We need to normalize routine sexually transmitted infection (STI) testing as part of normal healthcare. And as much as we can, we need to talk about condoms. It’s an increasingly difficult conversation to have, especially when no one else is using them, but we can still try.”

Whitburn agreed, saying that syphilis must be included in routine STI testing, and that general practitioners should also ensure that pregnant women and their partners are tested throughout pregnancy. She also encouraged practices to display information about syphilis in waiting rooms to normalize testing for everyone.

Ambitious Goals

Australia’s National Syphilis Response Plan 2023-2030 aims for the virtual elimination of congenital syphilis and a significant reduction in the prevalence of infectious syphilis. Experts said that the country is not on track to reach the goals.

“The biggest concern is the rise in congenital syphilis, which can cause miscarriage, stillbirth, infant death, and lifelong disability if maternal infection is not detected and treated,” said Whitburn. Between 2016 and 2026, more than 30 infants died, with First Nations children disproportionately impacted.

“It’s sad because syphilis is so easily treated, as long as it’s tested for. But now we’re starting to see more complicated syphilis, and we have to refer patients to a different hospital,” said Ong.

But several encouraging developments could help tackle the disease. Doxycycline post-exposure prophylaxis (Doxy-PEP), an oral dose of the antibiotic doxycycline within 72 hours of having sex, has been shown to reduce the risk for syphilis and chlamydia by as much as 90%. It is recommended for use for men who have sex with men (MSM) and transgender women. Trials among heterosexuals are ongoing.

“We suspect that the slight decrease or plateau we’re seeing might be because of MSM using Doxy-PEP, which is contributing to less syphilis circulating in the population,” Ong said.

Because testing is crucial to find the disease, Ong said that blood tests remain the gold standard because the current available rapid test can’t distinguish between a current and past infection.

Melbourne Sexual Health Centre and the Burnett Institute are currently developing a new point-of-care diagnostic test and a rapid self-test that can distinguish between current and past infections. Studies are ongoing, and Ong hopes that the Therapeutic Goods Administration will approve the test in 2028.

“As bad as it is, we have some hope for the future,” Ong said.

Ong and Whitburn reported no relevant financial relationships.