Remain Alert for Syphilis

09 August 2024

There were 323 notifications of infectious syphilis in South Australia (SA) in 2023, a 17-fold increase since 2011. There has been a rise in syphilis cases in women of reproductive age and pregnant women, increasing the risk of mother-to-child transmission. Two cases of congenital syphilis have been reported in SA this year. Congenital syphilis can lead to premature delivery, stillbirth, neonatal death, and congenital abnormalities that may cause severe, permanent disabilities. Early diagnosis and treatment of syphilis is critical to preventing these and other poor outcomes and stopping onward transmission.

There is no longer a shortage of 1.2 million unit benzathine benzylpenicillin pre-filled syringes (Bicillin L-A) used in the treatment of syphilis and group A streptococcal infections. See TGA shortages.  

Doctors are advised to:

Maintain a high clinical suspicion for syphilis in all population groups

  • Primary syphilis may present with one or more typically painless ulcers at the site of infection.
  • Secondary syphilis may present with a rash and constitutional symptoms such as fever or malaise.
  • Consider syphilis testing on patients presenting with a generalised skin rash otherwise unexplained.
  • Be alert to new visual complaints or loss of hearing and consider syphilis in the differential diagnosis. Ocular and neurological symptoms may occur at any stage of syphilis.
  • Always send blood for serology when any stage of syphilis is suspected. Additionally, request PCR for suspected syphilitic lesions (primary or secondary) using a swab suitable for molecular testing.

Consider syphilis screening in all sexually active patients

  • All asymptomatic sexual health checks and MBS item 715 assessments for Aboriginal and Torres Strait Islander people should including syphilis and HIV testing.
  • Test for syphilis and HIV in persons diagnosed with an STI, or a contact of a person with an STI.
  • Familiarise yourself with indications for testing in the ASHM Decision Making In Syphilis Tool.

Syphilis in pregnancy - universal repeat antenatal syphilis screening is recommended

  • Ascertain pregnancy status of your patient and their partners when testing for syphilis or other STIs.
  • CDCB recommends universal repeat antenatal syphilis screening at the first antenatal visit, 26-28 weeks, and 36 weeks (or at time of any pre-term birth). Neonates should not be discharged without offering a third screen if it has not occurred. Updates to relevant guidelines are in progress.
  • Additional screening should be considered for groups at increased risk including Aboriginal people (due to the current outbreak); people with new sexual partners during pregnancy, a recent history of any STI or is a contact of a person diagnosed with an STI, or people with limited antenatal care.
  • Urgently recall all pregnant persons with reactive syphilis serology to assess the need for treatment.

Consider use of doxycycline as post exposure prophylaxis (Doxy-PEP)

  • Discuss the potential use of Doxy-PEP with gay, bisexual or other men who have sex with men to reduce the risk of acquiring syphilis. See ASHM consensus statement.

Facilitate prompt treatment of syphilis and ensure appropriate monitoring

  • Treat patients with infectious syphilis promptly with 1.8g/2.4 million units benzathine penicillin (Bicillin L-A) via intramuscular injection (IMI).
  • Treat patients with non-infectious syphilis (i.e. asymptomatic infection with no evidence of seroconversion or fourfold rise in reactive plasma regain (RPR) titre in the previous two years) with 1.8g/2.4 million units benzathine penicillin IMI weekly for 3 weeks.
  • Treat contacts of syphilis presumptively with 1.8g/2.4 million units benzathine penicillin IMI and collect syphilis serology concurrently.  
  • Consider ordering benzathine penicillin through the PBS Emergency Drug Supply Schedule (Prescriber Bag), to minimise the risk of treatment delay.
  • Repeat RPR testing at 3, 6, and 12 months to monitor treatment response and exclude re-infection.

Notify new syphilis cases & cases requiring treatment in pregnancy (even if previously notified)

Seek advice and assistance from specialist services, if needed

Dr Louise Flood – Medical Lead, Communicable Disease Control Branch