1st measles case confirmed in Thunder Bay, Ont., since province-wide outbreak began
Sarah Law | CBC News | Posted: May 9, 2025 9:53 PM | Last Updated: May 9
Thunder Bay District Health Unit says risk to general public is low
The Thunder Bay District Health Unit (TBDHU) is reporting a lab-confirmed case of measles, which marks the first confirmed case in northwestern Ontario since the province's measles outbreak began in the fall.
"The individual acquired the infection through international travel and is now recovering at home," the TBDHU said in a news release issued late Friday afternoon.
"The public health investigation is unfolding. At this time, TBDHU is following up directly with known contacts, with a focus on those at higher risk. The risk to the general public is low."
TBDHU is advising people of the following potential for exposure to measles on May 4:
- Air Canada flight AC1195 – Toronto to Thunder Bay: 9:40 p.m. to 11 p.m. ET.
- Thunder Bay International Airport (YQT) terminal building 11 p.m. to 1:30 a.m. ET
Anyone who may have been exposed is asked to check their vaccination record and monitor for symptoms until May 25.
Ontario health officials said on Thursday that there have been 1,440 probable and confirmed cases of the previously eradicated disease since the outbreak began in October.
Northern Ontario's first measles case in 30 years was confirmed in North Bay in early March. Since then, cases have increased in the northeast but had not spread further west until this point.
Generally, people born before 1970 are considered immune. However, anyone born in 1970 or later should check their vaccination record to make sure they have received two doses of a measles vaccine, the TBDHU said.
Donna Stanley, director of health protection at the Northwestern Health Unit, told CBC News earlier this year that those who plan to travel internationally, attend post-secondary school or work in health care should consider a booster dose.
Those unsure of their vaccination status are encouraged to contact their health-care provider.
Symptoms of measles can include:
- Fever, runny nose, cough, red eyes.
- Small spots with white centres that appear inside the mouth.
- A red blotchy rash appears on the face then spreads down the body (which normally appears three to seven days after symptoms begin).
People should monitor for symptoms even if they are vaccinated against measles, the TBDHU said.
"Measles is a highly contagious disease that can spread easily to others through the air. Routine infant and childhood vaccination is usually given at 12 months and between four to six years of age," said Friday's news release.
"The vaccine is very effective against measles, even if the vaccine was received many years ago. Anyone who has not had two doses of a measles vaccine, for example, the measles, mumps and rubella (MMR) vaccine or has not had measles in the past is at risk of infection."
More information can be found on the TBDHU's website.