Neonatal Congenital Syphilis: Rising Cases And Treatment Challenges

Congenital syphilis is a preventable infection that occurs when Treponema pallidum passes from a pregnant person to the fetus. It can lead to miscarriage, stillbirth, prematurity, hydrops, low birth weight, bone and liver disease, hearing loss, neurological injury, or death. Some newborns appear well at birth, which makes reliable maternal screening and follow-up essential.

Australia has seen renewed concern about infectious syphilis and congenital cases, particularly in remote and regional communities. The pattern reflects gaps in antenatal access, late diagnosis, reinfection, partner management, workforce capacity and continuity of care. For neonatal teams, the challenge is to act quickly while recognising that the right treatment depends on maternal records, examination findings and the possibility of an incomplete evaluation.

Why Congenital Syphilis Is Reappearing

Syphilis can cross the placenta at any stage of pregnancy, although fetal transmission becomes more likely when maternal infection is recent or untreated. Primary and secondary syphilis carry a substantial risk, but early latent infection can also be transmitted. A pregnant person may have few symptoms, and a rash or genital lesion may have resolved before antenatal care begins.

The resurgence of cases is linked to several overlapping pressures. Sexual health services may be difficult to reach, particularly for people living in remote Aboriginal and Torres Strait Islander communities. Pregnancy can occur during periods of housing instability, family violence, substance dependence or interrupted contact with health services. Language barriers and concerns about stigma can further delay testing or treatment.

A positive result does not end the clinical work. Reinfection is possible if a partner remains untreated, and a declining antibody titre does not always provide a simple answer about treatment success. Services need systems that track repeat testing, document the exact penicillin regimen, confirm partner management and share information safely between sexual health, midwifery, obstetric and neonatal teams.

Australia’s Uneven Burden And Missed Opportunities

National screening recommendations provide a framework, but local implementation varies. Standard antenatal testing is generally performed early in pregnancy, with repeat testing later in gestation and at birth for people or communities with increased risk. Jurisdictional protocols may differ, so clinicians should use current state or territory guidance rather than relying on an old hospital pathway.

In the Northern Territory, Queensland, Western Australia and parts of South Australia, distance can turn a routine appointment into a major logistical task. A patient may travel from a remote community to a regional centre, change clinics during pregnancy or deliver in a hospital far from the service that recorded the initial result. Point-of-care testing, outreach midwifery and culturally safe care can reduce these gaps when they are properly resourced.

Other pregnancy exposures can complicate the clinical picture without explaining away infection. For example, research into air pollution and fetal growth highlights how environmental conditions may influence prematurity and birth weight. Those findings should encourage careful assessment of every vulnerable newborn, while a positive maternal syphilis result still requires its own urgent investigation and treatment pathway.

At birth, clinicians should ask whether the mother received an adequate regimen, whether treatment began early enough, whether follow-up titres were appropriate and whether exposure to a partner with untreated infection continued. Missing documentation should be treated as a clinical uncertainty, not as proof that treatment was completed.

Diagnosis And Treatment In The Newborn

Maternal serology usually provides the starting point. Treponemal tests often remain positive for life, while non-treponemal titres such as RPR or VDRL are useful for assessing disease activity and response. The newborn should have a careful examination, including the skin, mucous membranes, liver, spleen, bones, joints, eyes, hearing and neurological system. Findings may include snuffles, rash, jaundice, hepatosplenomegaly, anaemia, thrombocytopenia or pseudoparalysis, though an asymptomatic examination does not exclude infection.

Neonatal serum should be tested with a quantitative non-treponemal test, preferably using the same method and laboratory approach as the maternal test. Cord blood is less reliable because of maternal blood contamination. Depending on the maternal history and infant findings, evaluation may include a full blood count, liver studies, long-bone radiographs, cerebrospinal fluid examination and specialist ophthalmic or auditory assessment.

Penicillin remains the treatment of choice. Depending on the clinical category, treatment may involve intravenous aqueous crystalline penicillin G or intramuscular procaine penicillin G for a defined course. Doses are weight-based and change as the infant grows. A missed dose or interruption can require the course to be restarted, so inpatient teams need clear documentation and handover.

The response to treatment can produce a Jarisch–Herxheimer reaction, with fever, irritability, tachycardia or respiratory change soon after antibiotics begin. This reaction is not a reason to withhold penicillin, but it calls for monitoring and supportive care. Specialist advice is essential when the mother reports penicillin allergy, as desensitisation may be required during pregnancy and alternative antibiotics are generally not dependable substitutes for preventing fetal infection.

Coordinating Care Beyond The Nursery

Congenital infection care begins before delivery. Obstetric and sexual health teams should explain the result in plain language, arrange prompt treatment, provide partner notification support and record the date, dose and formulation of every penicillin injection. Aboriginal health workers, interpreters and community-controlled health services can help make care safer and more acceptable.

Neonatal clinicians should receive the maternal serology, treatment dates, titre history, antenatal ultrasound concerns and information about possible reinfection. A verbal handover is valuable, but the details also need to appear in the infant’s medical record and discharge summary. Families should leave with a named contact, a follow-up appointment and a clear explanation of why repeat blood tests may be needed even when the baby looks healthy.

Australia’s geography makes transport planning part of clinical care. Families may need to travel from the Kimberley, Cape York, the Top End or rural New South Wales to a tertiary neonatal service. A practical travel planning resource may help with logistics, but health services remain responsible for coordinating referrals, accommodation support and continuity of medication or testing.

Follow-up should include serial non-treponemal titres until the expected decline is documented. Persistent or rising titres require reassessment for missed treatment, reinfection or another explanation. Hearing, vision, developmental progress and neurological status also deserve attention because some effects become clearer during infancy rather than during the birth admission.

Practical Priorities For Australian Services

Local protocols work best when they are simple enough for busy maternity and neonatal teams to use during an overnight admission. Electronic prompts can flag missing maternal results, overdue repeat testing and incomplete treatment documentation. Audit should examine whether screening occurred at the recommended points, whether positive results led to same-day action and whether infants completed follow-up.

Perinatal specialists have long used placental examination to investigate infection, inflammation and poor fetal growth. The discussion of placental pathology in pregnancy is a useful reminder that placental findings can add clinical context, although they do not replace maternal serology or neonatal assessment for syphilis.

Services can strengthen prevention and treatment by focusing on the following actions:

• Offer early antenatal syphilis screening and repeat testing when recommended by local risk-based guidance.
• Use point-of-care testing and outreach services for communities where laboratory access or transport causes delays.
• Record penicillin type, dose, timing, adherence and partner management in a shared, accessible care plan.
• Treat possible reinfection as an urgent issue and provide confidential partner notification support.
• Ensure every exposed newborn has a documented examination, matched serology and a follow-up appointment before discharge.
• Build culturally safe pathways with Aboriginal Community Controlled Health Organisations and local interpreters.
• Audit congenital syphilis cases through a multidisciplinary review that includes maternity, neonatal, sexual health and public health teams.

The most effective response combines prevention, rapid diagnosis and reliable follow-through. Neonatal units should review their current pathway against Australian national guidance and state or territory requirements, then test it with realistic scenarios involving remote transfer, incomplete records and a newborn who appears well. Early action can prevent a lifelong burden from an infection that remains treatable.