Understanding, measles: why has Ontario more cases than all the United States?

Ontario has been ravaged since last October by a bleaching of measles last October which has made more than 1,400 infections and which led to more than 100 hospitalizations, even caught in the United States. Why can’t Ontario manage to master its hatching, unlike Quebec? We asked experts the question.

The current hatch of measles in Ontario, the most imposing in a decade, is linked to a gathering of mennonites in New Brunswick last fall, said the chief hygienist of Ontario, Dr. Kieran Moore.

However, while New Brunswick and Quebec have declared the end of their respective hatching, infections continue to multiply in Ontario.

There were 197 more cases in the last week in Ontario, for a total of 1440 infections since last October (1221 confirmed cases and 219 probable cases), according to the most recent report, published Thursday.

As a comparison, public Health in the United States (CDC) had identified, dated May 1, a total of 935 cases confirmed in 2025.

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Communities that reject vaccination

More than 76 % of cases in Ontario are children and adolescents. More than 95 % of them were not vaccinated, just like almost 61 % of infected adults.

Dr. Moore specifies that infections are concentrated in “rural and agricultural” communities in the southwest of the province, where the vaccination rate is particularly low.

Ontario Prime Minister Doug Ford stresses that these communities are opposed to vaccination for reasons religious and that this is a issue To protect other communities, he said.

You cannot grab their children by the arm and vaccinate them.

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Many mennonites refuse to be vaccinatedrecognizes Dr. Anna Banerji, specialist in infectious diseases at the University of Toronto.

It is partly bad luck. Measles could also strike other regions in the country with non -vaccinated populations.

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Dr. Moore says that documentation on the benefits of immunization and the symptoms of measles has been translated into the Germanic dialect spoken by the communities affected in the southwest. Public health also tries to transmit its message thanks to a local radio where we use this dialect.

Generally, children receive a first dose of the measles vaccine at the age of one year, then a second dose at the age of 4 to 6, ideally before entering school, says public health. However, it is possible in Ontario to have an exemption for medical or religious reasons.

A very contagious virus

The measles virus, which is transmitted by coughing or sneezing in the air, is particularly contagious, specifies Dr. Moore. A single infected person can transmit the virus to 16 other non -vaccinated people.

Same story on the part of Dr Isaac Bogoch, clinician and researcher on infectious diseases at the Research Institute of the Toronto General Hospital.

It is one of the most transmitted viruses on the planet. When he meets an unaccompanied population, he spreads like a forest fire.

There are other non-vaccinated or subvacinated communities elsewhere in Canada, and if the virus had to enter it, unfortunately, we would see the same thing as in Ontariohe said.

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A disease taken lightly?

The government should perhaps do more to reach the most affected communitiessays Dr. Hugues Loemba, virologist and clinician-researcher at the University of Ottawa and at Montfort Hospital, which adds that cases also appear elsewhere in the province.

About 80 % of infections are currently concentrated in the territories of five public health offices in the South West and South Ontario. However, cases have also been identified in the south-east and in the northeast of the province, as well as in the regions of Waterloo, Niagara and North Bay, in particular.

A total of 17 public health offices have reported cases, but not that of Toronto for the moment.

It is a much more serious disease than what we thinksays Dr. Loemba, who describes the measles as dangerous.

Measles can cause pneumonia, which can lead a child to intensive care. The virus can cause encephalitis. […] The consequences can be really serious, even until killing.

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The pandemic has undermined vaccination efforts, argues Dr. Loemba. Many children have missed their appointment or missed their follow-uphe said, adding that there has been an increase in opposition to vaccines with the bad press Online to the COVID-19 vaccine.

Lack of money for public health?

The average vaccination rate against measles of 7 -year -old children in Ontario is only 70 %, according to Public Health Ontario. In some regions such as Hamilton and Halton, the immunization rate is less than 50 %.

As a comparison, the immunization rate is around 90 % for Quebec students. The target of public health is 95 %.

According to Dr. Moore, Ontario data on vaccination is not always up to date because of the pandemic. But he admits that there is catch -up to be done in the province, precisely because of the pandemic. He adds that the province launched a program on this subject in 2023, particularly targeting children’s vaccination.

The Ford government says it has improved public health funding by 20 %. Dr. Thomas Piggott, hygienist doctor of the health office of Haliburton-Kawartha-Northumberland-Peterboroughretorts that the financing was not improved at the same rate as inflation.

[Les bureaux de santé publique] do not have the same capacities as during the Pandemic of Covid-19.

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His health office has not identified in cases of measles for the moment, but Dr Piggot is prepared to this possibility, noting that the vaccination rates in Ontario are not not sufficient To have collective immunity and to prevent hatching.

The liberal opposition accuses the government of Doug Ford of having merged health offices rather than investing in public health. The NPD claims a plan of the government to combat the hatching of measles.

Mother’s Day is approaching this weekend and families are concerned about an accidental exhibition for vulnerable children and for loved ones.

MP Stiles recalls that a 5 -year -old Ontario child who had measles died last year. She adds that New York State broadcast in April a warning for its residents about Ontario trips in the light of current hatching.

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The Ford government retorts that any Ontario who wishes it can be vaccinated for free of measles.

A formerly eradicated illness

The measles had been successfully eliminated in Canada In the past thanks to vaccination, underlines Public Health Ontario. However, cases have appeared around the world for a few years.

Dr. Piggottt is sorry to see that Ontario parents hesitate or refuse to have their child vaccinated, while when he worked for doctors without borders (MSF) in Congo, mothers could work for four or five days to go to a clinic in order to immunize their child. I saw children die of measles [au Congo]he said.

It is not all Ontarians who have a family doctor, but if it is not the case, it is possible to contact a local health office to obtain a vaccine, he advises.

In order to simplify the task for parents and for public health offices, he would also like that the province is investing in the creation of an electronic vaccination file register.

For Dr. Loemba, measles hatching represents the Iceberg Pointe of the post-pandemic sequelaestressing that other infections such as darling, for which vaccines exist, make them in Ontario. We have to make up for [en matière de la vaccination]he says.