Canada almost wiped out syphilis. Now rates are skyrocketing — as more women, infants getting infected

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Just a decade ago, syphilis infections among infants were nearly eradicated in Canada.

Yet there were warning signs the bacterial sexually transmitted infection (STI) — known for causing painless sores, organ damage, and stillborn infants — was making a comeback. First, rates started rising among adults in the early 2000s, followed by an alarming spike in congenital infections passed from mothers to their babies. 

The latest federal data shows there were nearly 14,000 cases of infectious syphilis across the country in 2022, as well as 117 instances of early congenital syphilis. That's a nearly 15-fold increase from just eight nation-wide cases of syphilis reported in infants five years earlier.

"When I started in clinical practice, just over 20 years ago, we'd see syphilis like every couple months," said Patrick O'Byrne, a nurse practitioner with Ottawa Public Health's sexual health clinic. "And I would say it's now daily."

There's no one reason to explain why syphilis is on the rise and in broader populations than before. Clinicians suspect changing sex practices and lack of health-care access for marginalized Canadians may create a climate where these infections can quietly run rampant.

Most concerning to Sean Rourke, a Unity Health Toronto scientist at the St. Michael's Hospital MAP Centre for Urban Health Solutions, is what he calls a lack of "political will" to fund and implement solutions as STI numbers "keep on going up and getting worse."

While federal officials have called syphilis an "ongoing crisis," Rourke said the situation should be dubbed an emergency that requires urgent on-the-ground efforts — before more vulnerable Canadians bear the brunt of escalating outbreaks.

"We're neglecting them," he said. "We've actually failed them."

A trio of bacterial STIs — chlamydia, gonorrhea and syphilis — were all rising steadily in Canada in the years before the COVID-19 pandemic, federal data shows.

While rates of chlamydia and gonorrhea dipped starting in 2020, likely due to reduced testing during COVID-related restrictions, syphilis maintained its upward trend after a briefer lull and remains a major concern for public health officials.

The STI is caused by the spiral-shaped bacterium Treponema pallidum, and transmits via direct contact with someone who's infected through vaginal, anal, or oral sex. Without treatment, syphilis can damage the heart, brain or other organs — and if someone is pregnant, it can spread to their fetus, leading to a high rate of stillbirths and a host of health impacts if the baby survives.

"They can be deaf, they can be blind, they can have learning disabilities," said Rourke. 

Alberta, Manitoba, Saskatchewan, and the Northwest Territories are among the hardest hit regions in recent years, according to federal figures. In recent years the country's syphilis rates were also rising faster than in the United States or Europe, a Reuters report noted in March 2023, which pinned the spike on poor health-care access and discrimination faced by Canada's Indigenous communities, concentrated across the Prairies.