Canada Loses Measles Elimination Status After Year-Long Outbreak

Canada has lost its measles elimination status after nearly three decades, following a sustained outbreak that began in October 2024 and has persisted for over a year. The Pan American Health Organization (PAHO) confirmed the status change on November 10, 2025, citing continuous transmission of the measles virus within the country.

The outbreak has resulted in more than 5,100 reported cases and two infant deaths as of November 2025. The virus has spread across nine provinces and one territory, primarily affecting under-vaccinated communities. The loss of elimination status indicates that Canada has experienced uninterrupted transmission of the measles virus for over 12 months.

Measles is a highly contagious viral disease characterized by symptoms such as high fever, cough, runny nose, and a distinctive rash. While most individuals recover, measles can lead to severe complications, including pneumonia, encephalitis (brain swelling), and death, particularly in young children and immunocompromised individuals. The disease is preventable through vaccination, with the measles-mumps-rubella (MMR) vaccine being highly effective.

Canada achieved measles elimination status in 1998, indicating the absence of continuous transmission of the measles virus for at least 12 months. This milestone was part of a broader regional effort, culminating in the Americas being declared measles-free in 2016. However, maintaining this status requires sustained high vaccination coverage and robust surveillance systems.

Several factors have contributed to the resurgence of measles in Canada:

• Declining Vaccination Rates: To prevent measles outbreaks, a vaccination coverage of at least 95% is necessary. By 2024, regional coverage had declined to 79%, facilitating the spread of the virus.
• Vaccine Hesitancy: Growing skepticism towards vaccines, exacerbated by misinformation and distrust in public health measures, has led to decreased immunization rates.
• Impact of the COVID-19 Pandemic: The pandemic disrupted routine immunization programs and diverted healthcare resources, leading to missed vaccinations and weakened surveillance systems.

The loss of measles elimination status has several significant implications:

• Public Health Impact: Increased risk of measles outbreaks, especially among vulnerable populations, leading to higher morbidity and mortality rates.
• Healthcare System Strain: Outbreaks place additional pressure on healthcare systems, requiring resources for outbreak control, treatment, and public education.
• Reversal of Public Health Gains: The resurgence of measles undermines decades of public health efforts and may erode public confidence in vaccination programs.

Canada's loss of measles elimination status also affects the broader Americas region. The region had previously achieved measles-free status in 2016, but this designation is now compromised. Other countries, including the United States and Mexico, have reported significant measles outbreaks in 2025, further challenging regional elimination efforts.

To regain measles elimination status, Canada must:

1. Interrupt Endemic Transmission: Demonstrate the absence of continuous transmission of the measles virus for at least 12 months.
2. Strengthen Immunization Programs: Enhance vaccination coverage to meet or exceed the 95% threshold necessary to prevent outbreaks.
3. Improve Surveillance and Data Sharing: Implement robust surveillance systems to detect and respond to cases promptly and share data effectively with national and international partners.

The Public Health Agency of Canada (PHAC) has committed to collaborating with PAHO and other partners to implement coordinated actions focused on these areas. In a statement, PHAC emphasized the importance of vaccination:

"The measles vaccine is the best way to protect you and your family. By staying vigilant and working together to increase measles vaccine coverage, we can prevent outbreaks and keep our communities safe against this preventable disease."

Health Ministers across the country have acknowledged the importance of health security and committed to coordinated actions, including strategies to build trust through community engagement.

The loss of measles elimination status in Canada serves as a stark reminder of the importance of maintaining high vaccination coverage and robust public health infrastructure. Addressing vaccine hesitancy and improving immunization rates are critical steps toward regaining elimination status and preventing future outbreaks.