Canada Faces Loss of Measles Elimination Status Amid Outbreak

Canada is on the brink of losing its measles elimination status, a designation it has maintained since 1998. The World Health Organization (WHO) defines measles elimination as the cessation of disease transmission for a minimum of 12 months. Canada is set to cross this transmission threshold at the end of October 2024, following an outbreak that has already resulted in over 5,000 cases this year—more than double the total from the past 25 years combined.

In light of this alarming situation, the Pan American Health Organization (PAHO) will hold its annual meeting of the Measles and Rubella Elimination Regional Monitoring and Re-Verification Commission this November to assess Canada’s status.

Understanding Measles and Its Impact

Measles is a highly contagious viral infection transmitted through respiratory droplets. It has the potential to infect between 12 and 18 individuals from one contagious person, making it one of the most infectious diseases globally. Approximately 40 percent of those infected require hospitalization, and the disease can be fatal, particularly for unvaccinated children. Before the introduction of the vaccine, measles caused an estimated 2.6 million deaths annually worldwide.

Comparatively, the United States has reported 1,596 cases and 44 outbreaks in 2025. While this figure is significantly lower than Canada’s, it still represents a fivefold increase from the 285 cases reported the previous year. Both countries have seen their vaccination rates dip below the critical 95 percent threshold necessary to prevent outbreaks.

The Role of Vaccination and Public Health Response

According to data from BlueDot, a platform providing international infectious disease data founded by Dr. Kamran Khan, the vast majority of Canada’s measles cases—around 95 percent—have occurred among unvaccinated individuals or those with uncertain vaccination status. The decline in vaccination rates, attributed to vaccine hesitancy and disruptions in routine immunizations during the COVID-19 pandemic, has significantly contributed to the resurgence of measles.

Travel has also played a crucial role in the outbreak. The Public Health Agency of Canada identified international travel as the catalyst for the initial infections. Since then, Canada has reported thousands of cases across ten jurisdictions, including hundreds of hospitalizations and two deaths among infants who contracted the virus before birth.

Provinces like Alberta have faced severe challenges, with vaccination rates for the measles, mumps, and rubella (MMR) vaccine falling to 72 percent among children by age seven in 2024, down from 82 percent in 2019. This decline has resulted in Alberta recording nearly 2,000 cases since March, giving it the highest per capita case rate in the country.

Ontario, with a population more than three times that of Alberta, reported 2,375 cases as of early October. The province declared its outbreak over on October 6 after a 46-day period without new cases, although vaccination rates for children in Ontario have also declined, dropping to 70.4 percent from 86.1 percent in 2020.

Public health experts emphasize that increasing vaccination rates is essential to restoring Canada’s measles elimination status and preventing the disease from becoming endemic again. Dr. Mariana Torres Portillo, head of surveillance at BlueDot, noted that several countries have successfully regained their measles-free status after significant outbreaks, highlighting that “hope is not lost.”

All regions of the World Health Organization have committed to eliminating measles by 2030. As Canada prepares for the upcoming assessment by the PAHO, the focus remains on boosting vaccination efforts to protect public health and maintain the progress made over the past decades.