Public Health Updates for Clinicians: Congenital Syphilis on the Rise in Windsor and Essex County

Alert Date
Location
Ontario

Rates of syphilis have been rapidly increasing nationally, including among females aged 15-39. As a result, rates of congenital syphilis have increased 1,271% nationally1 with 96 confirmed cases reported in Canada in 2021, up from just 7 cases in 2017. As of November 28, 2023, 2 confirmed cases of congenital syphilis have been reported in Windsor and Essex County in 2023 and 2 cases in 2022, while there were no cases for several years.

Syphilis can be transmitted from an infected pregnant person to a fetus at any stage of pregnancy via transplacental transmission or at the time of delivery. Congenital syphilis clinical presentations include stillbirth, hydrops fetalis, preterm birth, rhinitis, snuffles, rash, hepatomegaly, splenomegaly, lymphadenopathy, neurosyphilis, hematological abnormalities, Hutchinson’s teeth, among other symptoms2. People who experience unstable housing and who use substances are disproportionately impacted by syphilis during pregnancy. Barriers to accessing prenatal care due to social and/or environmental factors can also increase the risk of congenital syphilis3. 

PRENATAL SCREENING FOR SYPHILIS

The Public Health Agency of Canada (PHAC)  recommends4:

  • Universal screening for all pregnant people in the first trimester or at the first prenatal visit; 
  • Repeat screening at 28-32 weeks (or as close to this interval as possible) and again at delivery for pregnant people at ongoing risk of infection or reinfection and in areas experiencing syphilis outbreaks;
  • Consider more frequent screening for pregnant people at high risk;
  • Screening of all people who deliver a stillborn infant after 20 weeks gestation; and
  • Testing of infants with signs or symptoms compatible with early congenital syphilis symptoms even if their mother was seronegative at delivery as they may have become infected near-term.

SCREENING NON-PREGNANT INDIVIDUALS FOR SYPHILIS

It is recommended that the following individuals be screened for syphilis: 

  • All sexually active persons with new or multiple partners, and/or upon request of the individual (individuals with multiple partners to be screened every 3 to 6 months)4
  • Gay, bisexual, and other men who have sex with men (be screened every 3 months) 4
  • People living with HIV (be screened every 3 months) 4
  • People who are or have been incarcerated (be screened every 3 months) 4
  • People who use substances (be screened every 3 months) 4
  • Some indigenous communities (be screened every 3 months) 4
  • Unprotected sexual activity involving contact with oral, genital, or anal mucosa4;
  • Having experienced or experiencing homelessness and/or street involvement4; 
  • Sexual contact with a known case of syphilis or other STBBI4; 
  • Substance use, including chemsex 4 (sexual activity while under the influence of drugs);
  • Previous syphilis, HIV infection or other STBBI4,8; 
  • Sex with someone from a country/region with a high prevalence of syphilis7; and/or
  • Anonymous sexual partnering8.

Maternal syphilis cases experience a high incidence of co-infection with other sexually transmitted and blood-borne infections (STBBIs). Testing for chlamydia, gonorrhea, Hepatitis B and C, and HIV should be recommended alongside syphilis screening5. For more information on testing, please visit Test Information Index - Public Health Ontario. 

ASSESSMENT OF NEONATES 

All neonates should be evaluated for presumed congenital syphilis if they were born to3:

  • People with untreated syphilis at the time of delivery;
  • People treated for syphilis within 4 weeks of delivery;
  • People treated for syphilis during pregnancy without penicillin;
  • People treated for syphilis prior to pregnancy with insufficient serologic follow-up;
  • People with evidence of reinfection or relapse post-treatment (e.g., fourfold increase in antibody titer);
  • People who do not demonstrate an adequate response (fourfold decrease in titer) despite appropriate penicillin treatment;
  • People without a well-documented history of syphilis treatment.

Serologic tests may be negative during pregnancy, with symptoms not apparent until later in life. Since most infected infants are asymptomatic at birth, it is critical that neonates are not discharged from the hospital without confirmation that either the newborn or mother received appropriate serologic testing3.

TREATMENT

Pregnant individuals should be treated with the recommended penicillin regimen for their stage of infection, and treatment should be initiated at least one month prior to delivery4. Fetal infection can be prevented if maternal treatment is received before 16 weeks gestation4. Consultation with an infectious disease specialist should be considered when pregnant individuals are diagnosed with infectious syphilis and congenital syphilis is suspected. Medication can be ordered free of charge from WECHU at: STI Medication Order Form. 

RESOURCES

  1. Infectious and Congenital Syphilis in Canada, 2021 - Public Health Agency of Canada (PHAC)
  2. Congenital Syphilis: No longer just of historical interest (2018) - Canadian Paediatric Society
  3. Congenital Syphilis - National Collaborating Centre for Infectious Disease
  4. Syphilis guide: Screening and diagnostic testing - Canada.ca
  5. Congenital Syphilis: A Guide to Diagnosis and Management - Paediatric Child Health
  6. Syphilis Guide: Screening and Diagnostic Testing - Public Health Agency of Canada
  7. Evaluating the Global, Regional, and National Impact of Syphilis: Results from the Global Burden of Disease Study 2019 - Scientific Reports
  8. Early Syphilis: Risk Factors and Clinical Manifestations Focusing on HIV-Positive Patients - BMC Infectious Diseases 

For questions or concerns, please contact us at:

519-258-2146, ext. 1420.
Infection Disease Prevention Department
Windsor-Essex County Health Unit
Ph. 519-258-2146 Ex. 1420
Fx. 226-783-2132