Colorized electron micrograph of Treponema pallidum, the spiral-shaped bacteria that cause syphilis. The latest federal data shows there were nearly 14,000 cases of infectious syphilis across Canada in 2022, as well as 117 instances of early congenital syphilis. (CBC News/NIAID)
Nearly 14,000 cases of infectious syphilis across Canada in 2022, and 117 congenital infections
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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.”
Canada-wide crisis, data shows
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.
Alarming number of babies being born with syphilis in Canada
But the crisis is Canada-wide. In Ontario, rates hit their highest level in 2022 at nearly 24 cases per 100,000 people, with a year-end tally of more than 3,500 infections. (That’s close to the same number of cases reported across the entire country in 2016.)
The province has also documented a striking shift in which populations are getting infected.
While syphilis traditionally showed up more among males — and largely men who have sex with men, several experts noted — Ontario public health officials have observed steady increases among females, with the rate jumping from less than one case per 100,000 females in 2013 to 7.5 cases per 100,000 females by 2022.
There’s a similar trend playing out in B.C., with the province’s latest data showing the proportion of new syphilis cases in men who have sex with men has dropped from 84 per cent in 2018 to 33 per cent by mid-2023.
Meanwhile the proportion of infections among men who only have sex with women, and women who only have sex with men, has risen dramatically during the same five-year span — with those two groups now making up the vast majority of all syphilis infections in B.C., jumping from 14 per cent of the grand total in 2018 to 65 per cent last year.
“And we will expect that some of those individuals will potentially have some cases of congenital syphilis, especially if there are barriers to access to health care during that pregnancy,” noted Dr. Troy Grennan, the physician lead for the HIV/STI program at the B.C. Centre for Disease Control (BCCDC).
He called that a “devastating, preventable” outcome. (Syphilis caught during someone’s pregnancy through a prenatal screening can be treated with a basic regimen of penicillin.)
Multiple experts agreed marginalized groups including Indigenous communities, homeless individuals, and drug users are bearing the brunt of congenital infections.
Adam Grant, an Edmonton-based registered nurse and sexually transmitted and blood-borne illness team lead with Indigenous Services Canada, has met with pregnant individuals who find out they’re infected with syphilis at various points in their pregnancy. In many cases, those people live in remote areas and lack transportation to access care, or simply don’t have a primary care provider.
“Some individuals gave birth,” he said, “and then found out they had syphilis, because they never had prenatal care prior.”
N.W.T. officials deploy rapid tests to curb spread of syphilis
Shifts in sexual practices may be fuelling STI rise
While vulnerable communities may be more at risk, several experts suspect shifts in overall sex practices are partially fuelling syphilis’s comeback.
The rise of online dating apps, resulting in more people having multiple sexual partners, is one leading theory. A trend toward more oral sex could also be playing a role, said O’Byrne from Ottawa Public Health, who stressed that people think it’s safer because it’s not a likely transmission route for HIV, even though it’s a common transmission route for syphilis.
The growing use of pre-exposure prophylaxis (or PrEP) medicine — which has proven highly-effective in preventing HIV infection — also understandably led to behavior changes, Grennan noted.
“Some people now use condoms less frequently,” he added. “Or not at all.”
Awareness of bacterial STIs also dropped over time, leading clinicians to assume syphilis was no longer a threat, noted Dr. Kevin Woodward, an associate professor at McMaster University in Hamilton and the medical and executive director at HQ Toronto, a health hub offering STI and HIV testing.
More physicians need to include syphilis in routine screenings, he said. And that’s if someone even has a primary care provider in the first place, with surveys suggesting one in five Canadians don’t have a family doctor or nurse practitioner they can see regularly.
