Written by SHFPACT. Posted in Health Information Brochures


Syphilis is a sexually transmitted infection caused by a bacteria, Treponema pallidum. It is not as common in Australia as it is in some other countries, but there have been increasing diagnoses recently. It is easily treated with antibiotics, but without treatment, it can cause serious health problems. Typically syphilis is known as having three stages: primary, secondary, and latent (latent has two stages – ‘early latent’ and ‘late latent’). The primary, secondary and early latent stages are sometimes called ‘infectious syphilis’ as these are the most infectious stages. Late latent syphilis requires treatment, but is not very infectious.


You can catch syphilis by having contact with a syphilis sore or rash. Using a condom for all sexual contact will reduce the risk of transmission. The most infectious time is when a partner has a syphilis sore (chancre), and direct skin to skin contact occurs with that sore. A person with a syphilis rash (as seen in secondary syphilis) is also more infectious. Early diagnosis and treatment, and using condoms for sexual contact, can greatly reduce the risk of infection. Pregnant women can also pass the infection on to their unborn baby though the placenta, with very serious effects on the foetus (congenital syphilis).


Primary Syphilis

In the first stage (primary syphilis) there may be no symptoms, but typically a painless ulcer or sore (chancre) appears about 3-4 weeks after infection. Because it is painless, it may not be noticed, especially if it’s in a part of the body not easily seen, e.g. the anus, cervix, or mouth. A chancre has large numbers of the Treponema bacteria present and is highly infectious. The size of the ulcer can vary from 3mm to 3cm. There is usually only a single chancre present, but some people may have multiple chancres. It usually has a dry base, but sometimes can be weepy with discharge in the base. Chancres can occur on any surface that has had contact with syphilis.

They usually clear up after 2-6 weeks, but the infection remains in the body if no treatment has been given, and can progress to the next stage. In primary syphilis, the infection can be passed on to others even if there are no symptoms or if the sore has healed.

Secondary Syphilis

Second stage (secondary syphilis) occurs about 2-4 months after infection if there has been no treatment. This stage usually lasts a few weeks, but it can come and go for up to two years if not treated. The most common symptom is a painless, red rash on the trunk, hands, and feet, including the palms and soles. The rash is highly infectious. There may also be flu like symptoms, swollen lymph nodes, tiredness, and a genital rash which can also come and go.

Latent Stage Syphilis

Latent stage syphilis occurs after the second stage ends if there has been no treatment. It can be further divided into Early latent and Late latent. Early latent syphilis has no symptoms and can last for years. It is considered infectious, mostly in the first two years. If untreated, it can progress to Late latent syphilis in about one-third of cases. (This is sometimes called tertiary syphilis.) Late latent syphilis can cause damage in almost any part of the body including the blood vessels, heart, joints, brain, eyes, and spinal cord, and may cause mental illness, blindness, deafness, paralysis, valvular heart disease, and death. Late latent syphilis is not considered infectious.


Syphilis can be prevented by using condoms correctly every time you have sex, and also by you and your sexual partner/s having regular testing for sexually transmitted infections with early treatment when infection is found. For useful tips on condom use, check out our condom fact sheet.


A blood test looking for antibodies to the Treponema bacteria can diagnose syphilis and is also used to monitor response to treatment. Sometimes more than one test is needed. If a chancre is present swabs can be collected for direct detection of the presence of the bacteria. Blood tests which are done routinely during pregnancy include syphilis testing.


Syphilis is treated with antibiotics, usually long-acting penicillin as an intramuscular injection. Late latent syphilis requires a longer course of treatment then the other stages. If a patient with syphilis has a severe allergy to penicillin alternative antibiotic treatment is available.

Some people, especially those with early stages of infection, are likely to experience a flu like illness when they have been treated. This is known as Jarisch-Herxheimer reaction. If it occurs it usually does so 6 – 12 hours after treatment and the severity varies. Symptoms may include fever, headache, sweats and joint pain. It lasts for several hours, and simple supportive treatment of an analgesia such as paracetamol, fluids and rest is usually all that is required. After treatment sexual contact of any type should be avoided until the rash or chancre has healed, and until at least one week after treatment has finished. Your partner/s may need treatment, and you need to wait for one week after their treatment before having sexual contact to avoid being re-infected. Follow up blood testing at 3 and 6 months (and sometimes 12 months) is usually recommended to ensure the treatment has been effective.


Sexual partners need to be advised that you have been diagnosed with syphilis as they will need testing and treatment. If they do not have treatment, they could end up with very severe problems (tertiary syphilis) and may even re-infect you. You will need to discuss with your practitioner how far back contact tracing is required as it could be as far back as 12 months or more.

There are websites that you can use to help contact your partners for example: or

Syphilis and HIV

The presence of syphilis can enhance HIV transmission, and it is an indication for HIV pre-exposure prophylaxis (PrEP) in men who have sex with men. Testing for syphilis and HIV is usually done at the same time or during the follow-up after treatment.

The presence of syphilis can enhance HIV transmission, and it is an indication for HIV pre-exposure prophylaxis (PrEP) in men who have sex with men. Testing for syphilis and HIV is usually done at the same time or during the follow-up after treatment.


If you are diagnosed with a sexually transmitted infection (STI), it is important to be checked for other STIs such as chlamydia. Your partners should also be notified, checked and treated if required. Be sure to have another test after treatment to make sure it has been cleared up.



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Last updated November 2017

Syphilis; Australian STI Management Guidelines
Syphilis, Australian Contact Tracing Manual >
Reexamining Syphilis: An Update on Epidemiology, Clinical Manifestations & Management > Molly E Kent, PharmD; Frank Romanelli, PharmD MPH BCPS The Annals of Pharmacotherapy 2008; 42(2):226-236. accessed 9/8/17 Sexual Health Information, Fact Sheets, Syphilis;
Melbourne Sexual Health Centre >

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