Alberta’s measles surge appears to be slowing, but with children back in school this week health experts caution another rapid upswing could be around the corner.
The magnitude of the province’s outbreaks has sparked widespread concern for months, eclipsing the total case counts for the entire United States in July.
Alberta continues to report more cases, on a weekly basis, than any other province in the country, according to the Public Health Agency of Canada.
However, the number of new measles cases confirmed each week has been trending downwards since peaking in July.
Seven more cases were reported over the long weekend — all of them in the north zone — bringing the total number identified since the outbreaks began in March to 1,826 as of noon Wednesday.
“There are still measles cases around the province but the number of new cases is decreasing, which is a good sign,” said Dr. Karina Top, a pediatric infectious disease specialist at Edmonton’s Stollery Children’s Hospital.
“We did see an uptick in people getting their [measles] vaccines earlier in the summer and so I think it’s thanks to those people and the efforts of public health to help get people vaccinated that we’re starting to see a down trend in the number of new cases.”
One person is currently in hospital due to the illness. As of Aug. 23, 152 Albertans have been hospitalized since the outbreaks began, including 15 intensive care unit admissions. No deaths have been reported this year.
“We’re not seeing as many sick kids recently with it, which is a good thing,” said Dr. Sidd Thakore, a pediatrician at Alberta Children’s Hospital in Calgary.
Classroom risk
Thakore has treated children who are very sick with measles, which can lead to serious complications, including pneumonia, brain swelling and even death.
He’s watching to see what happens as kids head back to school and spend more time inside, in close contact
“Will we see another spike because of that? Time will tell. But it’s such a contagious virus for those that have symptoms that are going to be around people who are not vaccinated, there’s definitely a much higher risk for us to see those numbers go up again.”
Infectious diseases tend to spread more easily as people move indoors. Making matters worse, measles is a highly contagious airborne virus that can hang in the air for up to two hours after a person leaves a location.
“If a child is in a classroom with measles, within a couple of hours they’ll expose every other child in that classroom that is not protected against measles … and anyone who goes into the classroom for two hours after that child has left could also get measles,” said Top, who is also a professor of pediatrics at the University of Alberta.
Both doctors are urging Albertans to ensure their family is up-to-date with immunizations and to keep kids home when they’re sick.
The latest publicly available data shows in 2024 measles vaccination rates among young children were well below the 95 per cent threshold infectious disease experts say is required for herd immunity.
According to the province, two doses of the measles vaccine offer nearly 100 per cent protection.
The vast majority of confirmed cases continue to be among those who are not immunized.