Dr. Roussin pens letter to Manitobans as measles cases rise

Dr. Brent Roussin, Manitoba chief public health officer, speaks at the Manitoba legislature in Winnipeg Wednesday, Dec.16, 2020. (John Woods/The Canadian Press)

Manitoba’s chief provincial public health officer is spreading the word about how easily someone can get measles and why getting vaccinated against the disease is so important.

Dr. Brent Roussin has sent a letter to all school divisions, independent schools, and licensed child-care centres in the province about the recent measles outbreak.

The update dated May 8, 2025, is addressed to parents/guardians, staff and volunteers.

“Canada is now experiencing the largest measles outbreak since measles was declared eliminated in Canada in 1998,” Roussin wrote. “Outbreaks are also occurring in the USA and Mexico. Over 90 per cent of recent cases in Canada are unimmunized or have unknown vaccination status.”

Roussin also explained how easily measles spreads.

“Someone with measles can spread it to others from four days before the rash begins (before they know they are sick) to four days after the rash appears,” the letter reads.

It also said anyone who has not been vaccinated against measles or has not had measles before, will likely get infected if exposed.

The first five cases in Manitoba were reported in February 2025, since then, at least one new confirmed case has been reported each month. Manitoba Health has also issued 30 measles exposure notices for different locations or flights. As of May 10, 2025, there have been 44 confirmed cases in the province and four probable cases.

In Roussin’s letter, he wrote two doses of the measles vaccine are almost 100 per cent effective in preventing measles. He added breakthrough infections are possible, but they are typically milder and less likely to spread the disease to others.

He said if you think you have the measles, stay home and contact your health-care provider to get tested.

“If you have a household member who is unimmunized, they should also stay home while you are waiting for test results. This is because they may already be infectious even if they do not have symptoms,” he wrote.

His advice for Manitobans to protect their community school is that a measles-positive person must isolate for four days after their rash appears. He also said for someone exposed who is not immunized, they may need to stay home for three weeks after being exposed, a timeframe that could be extended if additional cases are found at the school.

Manitoba makes changes to measles vaccine eligibility

With spikes in confirmed cases in Manitoba, the province has altered its vaccine eligibility.

Infants between six months and under 12 months living in the Southern Health-Santé Sud and Interlake Eastern health regions are now eligible to get the MMR vaccine, which covers measles, mumps and rubella.

It is also available for children in that age bracket who travel regularly to or have close contact with people from those areas.

The province said an early dose doesn’t protect children from varicella, as the MMRV vaccine isn’t recommended for kids under 12 months old.

“All infants should still receive two doses of MMRV after their first birthday and at least four weeks after the previous dose of any measles vaccine to ensure long-lasting immunity,” the province said in a news release.

Manitoba Health updates measles cases weekly on Wednesdays.

- With files from CTV’s Devon McKendrick