About syphilis

  • The STI syphilis is caused by the bacterium Treponema pallidum.

  • In Australia, there were 5078 infectious syphilis cases diagnosed in 2018, a >300% increase since 2009.1

Diagnosis and treatment

  • There are different stages of syphilis infection, each characterised by different signs and symptoms at different time periods. Infectious syphilis refers to primary, secondary and early latent syphilis cases. Non-infectious syphilis refers to late latent and tertiary syphilis.

  • Syphilis testing should be routinely offered to pregnant people at the first antenatal visit, and should be repeated early in the third trimester, depending on local guidelines. Vertical transmission can occur at any time during pregnancy and any stage of syphilis and cause congenital syphilis. See the STI Management Guidelines for more information about testing and treatment during pregnancy. 

  • Syphilis is diagnosed through a combination of clinical assessment, serology and PCR of lesions. For guidance on how to test for syphilis and interpretation of syphilis serology refer to the ASHM syphilis decision making tool

  • Syphilis is a notifiable condition.

Notification in your state/territory

Syphilis is a notifiable disease in all Australian states/territories. The diagnosing clinician and/or the pathology labratory is responsible for notification, depending on the jurisdiction. Click on your state below for further information about notification in your jurisdiction.  Please note that information regarding notification is correct as of July 2022. Please check with your relevant Health Department for further updates. 

Follow-up and management

  • Antibiotic treatment for syphilis will vary depending on the stage of syphilis. Click here for more information.  

  • Advise the index case no sexual contact for 7 days after treatment, and no sex with past partners [from the last 3 months (primary syphilis), last 6 months (secondary syphilis) or 12 months (early latent)] until the partners have been tested and treated as appropriate.2 

  • All sexual contacts of patients with primary or secondary syphilis should be presumptively treated. 

  • All patients should be reviewed clinically and have repeat testing at 3 and 6 months after completing treatment to assess treatment response. Consider HIV and other STI testing at the 3-month visit.

For detailed information about syphilis, including diagnosis, treatment and management, see

Australian STI Management Guidelines: Syphilis | Syphilis Decision Making Tool | Syphilis Outbreak Training


1. Kirby Institute. National update on HIV, viral hepatitis and sexually transmissible infections in Australia 2009–2018. Sydney: Kirby Institute, UNSW; 2020.


MoCCA is funded by the National Health and Medical Research Council (APP1150014) and is a collaboration between the University of Melbourne and our project investigators and partner organisations in Victoria, New South Wales and Queensland. Click here for a list of our collaborators.

The information on this website was last updated in June 2024. 

We acknowledge and pay respect to the Traditional Owners of the lands upon which this research is being conducted.