Measles outbreak a ‘global resurgence’, infectious disease specialist says

A dose of the measles, mumps, and rubella (MMR) vaccination awaits the next patient during a vaccine clinic at Southwestern Public Health in St. Thomas, Ont. on Tuesday, March 4, 2025.THE CANADIAN PRESS/ Geoff Robins (Geoff Robins/THE CANADIAN PRESS)

Measles infections in Canada have surged to 227 confirmed cases since the start of this year, surpassing the total for all of 2024 in a trend one infectious disease specialist calls “concerning.”

Isaac Bogoch, a clinician and researcher with University Health Network, says the outbreak is particularly troubling due to its transmissibility and the global resurgence of the disease.

“This outbreak is not unique to Canada,” he said in an interview with CTV News Friday.

Data from the Public Health Agency of Canada (PHAC) shows that cases connected with outbreaks in New Brunswick, Ontario, Quebec and Manitoba have been surging.

“And while most of Canada is immune and our vaccination rates are typically very high, we certainly have pockets within the country where the vaccine rates have dipped,” says Bogoch.

He says the most vulnerable populations are the unvaccinated or under-vaccinated children and immunocompromised individuals.

“There’s this misconception that this was just a routine childhood illness that everyone used to get decades ago, and everyone was fine,” Bogoch said.

“This can have significant morbidity and even mortality associated with it, about 100,000 deaths per year, mostly in children around the world.”

Ten to 15 per cent of cases in Canada could potentially result in hospitalization, he said.

“It is not a benign childhood illness,” says Bogoch. “There are certainly complications associated with it, and it is totally preventable.”

The country’s chief public health officer, Theresa Tam, released a statement on Thursday warning the public of the “concerning trend.”

“As we move through spring break travel season, I am concerned that the global rise in measles cases, combined with declining vaccination rates among school-aged children in Canada, could lead to more illness and more community transmission,” Tam said.

“I strongly urge all Canadians to ensure they are vaccinated against measles —check to see if you are up to date before travelling.”

A few of the recent cases in the provinces affected came from travelers who were exposed to the disease in another country, Tam stated.

The decline in vaccination rates is attributed to missed doses during the pandemic and disinformation, according to Bogoch.

He believes an effort needs to be made to lower barriers to vaccinations, to increase accessibility.

Common symptoms and signs

Symptoms can appear seven to 21 days after being infected with the virus, according to the Canadian government’s website.

They initially present as fever, cough, runny nose, and red, watery eyes.

Three to seven days after the symptoms start showing, a rash that looks like red spots and blotchy patches appears, starting from the face and then spreading to the rest of the body.

This rash can last four to seven days, the website said, and recovery can take two to three weeks.

However, there are some complications that can arise due to this disease.

The most common ones include ear infections, pneumonia and diarrhea.

Measles can sometimes result in hospitalization leading to severe complications like respiratory failure, swelling of the brain (encephalitis) and death.

There is also a possibility of developing a neurological condition called subacute sclerosing panencephalitis, seven to 10 years after recovering from measles.

Pregnant people who get infected with this virus could have a miscarriage, go into premature labour, or give birth to an infant with a low birth weight, the government said.

People who develop symptoms are asked to isolate at home and call a health care provider immediately for further treatment.

Although, there are no specific anti-viral treatments for measles, medications are available to help relieve and manage the complications.

The Canadian government has stated that all countries have a travel health notice that advises travelers to be careful and be up to date with their vaccinations.

With files from CTV News’ Christl Dabu