Syphilis on the rise: dial up screening and “test it away”

BETWEEN COVID-19, influenza and respiratory syncytial virus, GPs now have to keep a weather eye on their at-risk patients as syphilis numbers continue to rise in vulnerable communities, leading to calls for increased screening in those groups.

According to the National Communicable Disease Surveillance Report for 30 May to 12 June 2022, there is an “ongoing outbreak” occurring in men who have sex with men (MSM), predominantly 20–39 years of age, in urban areas, in women aged 20–39 years (both Aboriginal and Torres Strait Islander and non-Indigenous) in urban areas, and Aboriginal and Torres Strait Islander people in northern and central Australia.

“This is a very significant rise. Syphilis is a serious infection and we need to take it very seriously,” said Professor Christopher Fairley, Director of the Melbourne Sexual Health Centre and Professor of Public Health at Monash University.

Syphilis is a bacterial sexually transmitted infection caused by Treponema pallidum. There are four stages – primary, secondary, latent, and tertiary.

Primary syphilis presents 2–4 weeks after infection as a painless sore at the site of infection, and can often go unnoticed, depending on where it develops. Without treatment the sores will self-resolve but the patient remains infectious. Secondary syphilis can occur 7–10 weeks after infection. Symptoms include rash, fever, enlarged glands, sore throat, hair loss, weight loss, headaches, ulcers in the mouth, nose or genitals, and neurological symptoms. Latent syphilis is asymptomatic and can only be detected via a blood test – it is infectious for 12–24 months. Tertiary syphilis (5–20 years after infection) can damage any part of the body, including the heart, brain, spinal cord, eyes and bones.

Treatment for syphilis remains intramuscular penicillin, which remains highly effective against T. pallidum.

What’s causing the rise?

“It’s a very good question,” said Professor Fairley.

“If you have adequate access to health care and a population that presents when they get symptoms, you will get adequate control.

“What drives the increased incidence of syphilis in MSM is complicated, but it relates in part to society’s stigma against them. Stigma pushes them away into a corner and says, you know what, I don’t really respect your relationships.

“When you put stigma on people, they increase their risk-taking behaviours – more drug-taking, for example, and more sexual partners. They also don’t like accessing health care because of the stigma they feel.”

Compounding that, Professor Fairley told InSight+, were the current challenges in accessing general practice care, either through waiting times, lack of workforce, or rising costs.

“The shortage of GPs, the cost of going to GPs, the fact that sexual health services are being stretched – all those things make it harder for people to get access to health care.

“And fast access to health care is vital in the context of syphilis, because it means that instead of being infectious for 3 months or 6 months, it’s infectious for 6 days. It’s much harder to transmit if it’s only infectious for 6 days rather than 6 months.”

Any routine test of HIV in MSM was an opportunity to test for syphilis, he said.

“When you go and have an HIV test, you should have a syphilis test. People know about the HIV test, but they don’t really know about syphilis testing – both should happen.

“HIV and syphilis have similar risks, and they both should be tested for at the same time.

“We know that if you increase testing, you shorten the duration of infection, which means you improve control.”

The rise in syphilis in women of reproductive age is particularly concerning, said Professor Fairley. Syphilis in pregnancy can transmit the infection vertically resulting in congenital syphilis, and is associated with “serious perinatal consequences” such as premature birth, intrauterine growth restriction, miscarriage, stillbirth, and perinatal death.

In July 2022, McKenzie and colleagues recommended that antenatal testing for syphilis be increased to three tests.

“Routine syphilis testing at the first antenatal visit is advised by the Australian sexually transmissible infections guidelines,” they wrote.

“A test early in the third trimester is recommended depending on local guidelines. As syphilis rates grow in many parts of Australia, other jurisdictions should consider adopting additional routine syphilis screening for all pregnant women.”

Professor Fairley agreed.

“What stops congenital syphilis in women is proper antenatal testing,” he told InSight+. “There are moves to test pregnant women more frequently, not just once but three times during the pregnancy.”

In Aboriginal and Torres Strait Islander communities the rise of syphilis could be attributed to lack of access to health care, but also to growing resistance of T. pallidum to another commonly used antibiotic, said Professor Fairley.

“Azithromycin was used commonly in Indigenous populations to treat chlamydia, gonorrhoea and other things, and incidentally it probably made syphilis non-infectious.

“But syphilis has now become resistant to azithromycin. So that background use of antibiotics for other STIs isn’t working anymore for syphilis,” he said.

Professor Basil Donovan, Head of the Sexual Health Program at the Kirby Institute at UNSW Sydney, told InSight+ that “health system failures” were responsible for the rise of syphilis in remote Aboriginal and Torres Strait Islander communities.

“They just don’t get tested often enough. Their sexual behavior isn’t particularly unusual, it’s just they don’t have access to health services. We’re trying to get those health services to test more often.”

Screen, screen, screen

The answer, said Professor Fairley, was to screen patients in vulnerable populations as often as possible.

“If your patient is at risk of acquiring syphilis – if they’re young and sexually active, if they are a man having sex with men, or a woman who is a partner of a man having sex with men, or a transgender woman – test for syphilis,” he said.

“Any neurological symptom [in those patient groups] can be syphilis – balance problems, weakness, facial droop, ringing in the ears, funny visual things – anything can be syphilis.

“Test them.”

Professor Donovan agreed.

“In an ideal world I’d be encouraging young Aboriginal people to go and get tested,” he said. “But we must resource health services to do those tests.

“In the case of gay men, if you’re doing an HIV test, it’s almost criminal not to test for syphilis as well. And yes, we need multiple tests during pregnancy.

“We have to test it away as much as we can.”

The MJA has today published a report of a case of neurosyphilis with multiple cranial neuropathies in an immunocompetent 65-year-old man.

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