Measles Outbreak in Northern Ontario: 96 New Cases Reported This Week

Public Health Ontario is grappling with a growing measles outbreak, reporting 96 new cases in the past week, bringing the total number of infections to 2,179 since the outbreak began in October 2024. This surge marks the third consecutive week of increased cases in the province, particularly impacting the Algoma Public Health region, which includes Sault Ste. Marie. The area has recorded 115 cases to date, with three hospitalizations attributed to the outbreak.

The escalation in measles cases comes after the first infection was confirmed in April 2025. Dr. John Tuinema, the associate medical officer of health for Algoma, highlighted that the recent rise was anticipated, as it follows a pattern observed in Southwestern Ontario several months prior. He expressed cautious optimism, noting that the northern region is less likely to experience the same magnitude of infection due to a higher vaccination rate and smaller population size.

According to data from Algoma Public Health, vaccination rates are notably high, with 87% of seven-year-olds and 97% of 17-year-olds immunized against measles. "When we do have a case, if they do have contact with people who are immunized, that kind of quickly hits that wall of herd immunity. But it’s still sort of working its way through some of the unimmunized population. It’s almost exclusively been in private settings, such as households," Dr. Tuinema explained.

In contrast, Southwestern Public Health, identified as the provincial hotspot for measles, has reported a total of 751 cases, including 12 new infections over the last week, which have shown a declining trend in recent weeks. The situation in Southwestern Ontario has prompted health officials to implement various community health measures to contain the outbreak.

Experts emphasize the importance of vaccination in preventing further spread. Dr. Kieran Moore, Chief Medical Officer of Health for Ontario, reiterated the necessity for all eligible individuals to receive the measles vaccine, particularly in light of the current outbreak. He stated, "Vaccination is the most effective way to prevent measles and protect our communities."

As the outbreak continues to unfold, health authorities are closely monitoring the situation, urging parents to ensure their children are vaccinated and promoting awareness of the measles symptoms, which include high fever, cough, runny nose, and a distinctive rash.

In light of this situation, Public Health Ontario plans to conduct more outreach and educational campaigns aimed at encouraging vaccinations among communities at risk of exposure. The health unit also intends to collaborate with schools and community organizations to disseminate crucial information regarding the outbreak and vaccination benefits.

The implications of the ongoing measles outbreak extend beyond individual health, potentially affecting public health policy and vaccination strategies across the province. As Ontario navigates this public health challenge, the importance of maintaining high vaccination coverage remains paramount to preventing similar outbreaks in the future.