Ontario Declares Year-Long Measles Outbreak Over

Signs warn of a measles alert at the Taber Community Health Clinic in Taber, Alta., on July 28, 2025. The Canadian Press/Jeff McIntosh

Ontario has declared its measles outbreak over after more than 2,000 cases were reported in the province over the past year.

Public Health Ontario declared the outbreak over as of Oct. 6 in an epidemiology report last updated on Oct. 9. An outbreak is declared over once 46 days have passed since the last outbreak case.

“Although the outbreak is declared over, measles continues to circulate in Canada and globally, so ongoing vigilance for measles case finding and public health follow-up will continue to occur,” the report said.

The province’s first outbreak cases occurred during the week of Oct. 28, 2024, after exposure to a travel-related case in New Brunswick on Oct. 18, 2024, the agency said, noting other provinces have reported measles cases related to the outbreak. New Brunswick declared its outbreak over in January.

While there were a total of 2,375 measles cases reported across 26 local public health units in Ontario during the outbreak, no additional outbreak cases have been reported since the week of Aug. 18 to 24.

There have also been 43 reported cases of non-outbreak related cases, including some related to travel or without a reported source of exposure.

Nearly three-quarters of people infected with measles in Ontario have been infants, children, and adolescents, the health agency said. Overall, 6.9 percent of outbreak cases involved hospitalization and 0.5 percent were admitted to the intensive care unit.

There was one death reported during Ontario’s outbreak, involving a baby in the womb who was infected with measles and died after the mother gave birth prematurely.

Measles was declared eliminated in Canada in 1998, but the Public Health Agency of Canada (PHAC) said the country could lose its measles-free status if there are 12 months of continuous transmission. Oct. 27 will mark one year from start of the current outbreak.

PHAC said the majority of measles cases this year have been in Ontario and Alberta, but there have been cases reported in every province, as well as one in the Northwest Territories, and no cases reported in Yukon or Nunavut.

Symptoms of measles include fever, cough, runny nose, and red, watery eyes, with a rash appearing three to five days after symptoms start, PHAC said. The rash “looks like red spots and blotchy patches that start on the face, and then spread down the body, arms and legs.” It can last four to seven days, with most people recovering from the infection within two or three weeks.

The Canadian Press contributed to this report.