Illuminating a dark field: a case of congenital syphilis in the context of rising rates in Australia and implications for screening guidelines.

Objectives To describe the changing landscape of congenital syphilis. Type of program We present a case report of congenital syphilis, highlighting some of the challenges in management, and placing it within the broader public health context of rising syphilis rates. Methods This article is a brief case report in the context of a broader narrative review of congenital syphilis, including clinical significance, recent epidemiological trends in Australia and evolving recommendations on screening. Results The rising rates of infectious syphilis across Australia, specifically an increase in incidence amongst non-Indigenous and Indigenous females of 22 and 11% respectively across 2023, is associated with an increase in congenital syphilis diagnoses. Concerningly, more diagnoses are occurring late in pregnancy, with 79% of reported cases since 2016 being either post-delivery or within the 30days prior. The 10 deaths reported in 2023 from congenital syphilis is the highest number of deaths ever recorded in Australia. Our case was diagnosed early in pregnancy but did not receive sufficient antenatal care to prevent vertical transmission, despite intensive public health involvement. Lessons learnt We note that rising rates of congenital syphilis have prompted New South Wales (NSW), Queensland (Qld), Western Australia (WA) and South Australia (SA) to now universally recommend screening for syphilis multiple times in pregnancy and no longer reserve this for high-risk populations; however, our case would not have benefitted from these recommendations, emphasising the need for broader public health interventions to reduce the prevalence of infectious syphilis in Australia.