Toronto

Ontario measles case count tops 800, 155 new infections since last week

Ontario is reporting 155 new measles cases over the last week, pushing the province's case count to 816 since an outbreak began in the fall. Public Health Ontario says there have now been 61 hospitalizations.

Public Health Ontario says there have now been 61 hospitalizations

A colourized electron transmission micrograph of measles virus particles.
A colourized electron transmission micrograph of measles virus particles. (U.K. Health Security Agency)

Ontario is reporting 155 new measles cases over the last week, pushing the province's case count to 816 since an outbreak began in the fall.

The number of new cases has increased again after a few weeks of appearing to stabilize in the 100-per-week range, which public health physicians had taken as a sign of potential optimism.

Public Health Ontario says there have now been 61 hospitalizations — that's 11 more than last week — including 47 children. Unimmunized kids are the predominant group infected by the outbreak.

Most cases are still in Ontario's southwestern public health unit, but they spread to two more public health units this week, including Hamilton and Northeastern, which covers Timmins and Englehart.

Dr. Susy Hota, division head for infectious diseases at the University Health Network, told CBC News she never thought she would see this many measles cases in Ontario. 

"I haven't seen numbers like that in my career, so it's it's very disturbing to see that," she said.

Hota says lower vaccination rates could be to blame for the outbreak. 

"It was always a background worry that vaccine-preventable diseases like measles could come back and have a resurgence if the vaccination levels were low enough," she said. "It's just unfortunate that we haven't had a chance to try and help catch up and get that message out to people before it really hit our population more locally."

Over 90 per cent of people who don't have protection through vaccination or previous infection will likely be infected if exposed to the virus, she said — and that's why people should find out if they're immune or not.

"If you know that you haven't been fully vaccinated, this is a time to get it done. You really want to try and get ahead of this before you end up in a situation where you may be exposed," she said.

Doctor says electronic vaccine registry would be 'absolutely critical'

Dr. Ninh Tran, medical officer of health at Southwestern Public Health, says there's been a 130 per cent increase in measles vaccinations at local public health clinics from January to April compared to last year.

That translates to an additional 940 doses in arms.

Tran also spoke about schools beginning to issue suspensions this week to some of the thousands of students who aren't fully vaccinated, and the urgent calls for the province to digitize its immunization record system.

WATCH | Ontario students react after suspensions issued to those not fully vaccinated: 

Ontario students react after suspensions issued to those not fully vaccinated

5 days ago
Duration 3:26
Ontario's Immunization of School Pupils Act mandates that students must be vaccinated against nine vaccine-preventable diseases or have a valid exemption on file. CBC's Clara Pasieka spoke to Toronto students as high schools begin to dole out suspension notices.

Physicians have been calling on the province to create a central digital vaccine registry for over a decade with the spread of measles shining light on the outdated yellow immunization cards.

Tran says an electronic vaccine registry would be "absolutely critical" to better understand vaccine coverage.

"People can't seem to find them," he says about paper-based vaccine records. "They have to sort of contact their health-care provider and then report it to us."

Alberta's case count nearly doubled over the last week to 46, as did Saskatchewan's now six infections. Quebec has remained at 40 for a fourth week.

Manitoba has reported 10 cases since February, including an exposure on a flight from Toronto to Winnipeg, according to the latest update Monday.

Measles usually begins with a fever, cough, runny nose and red watery eyes, followed by a red blotchy rash that starts on the face and spreads to the body and limbs.

The virus can lead to pneumonia, inflammation of the brain and death.

With files from CBC News