In a stark reversal of over 25 years of public-health progress, Canada has had its measles elimination status formally withdrawn, according to an announcement from the Public Health Agency of Canada (PHAC).Elimination status means a country has interrupted endemic (continuous) transmission of a disease for at least 12 months. Canada had been certified as eliminating measles in 1998.But a multi-province outbreak beginning in late 2024 and continuing into 2025 has shattered that record. The Pan American Health Organization (PAHO) has notified Canada that it no longer meets the criteria for elimination, Reuter's reported Monday morning.Between 1 January and 12 April 2025, Canada reported 1,069 confirmed and probable measles cases from seven provinces — a dramatic rise compared to the same period in 2024.Measles is one of the most contagious human viruses. To protect a population, public-health authorities estimate that at least 90-95% of a community must be immune (via vaccination or past infection).Evidence shows that Canada’s population immunity has declined. A serological survey found measles immunity below 95% in age bands 6–39 years.The outbreak is concentrated in communities with low vaccination uptake: PHAC reports 84% of cases were unvaccinated, 12% unknown vaccination status, said the World health Organization.PHAC has announced a recalibration of its strategy: boosting vaccine coverage, enhancing surveillance, better data-sharing across jurisdictions. Provinces are responding too — for example, in Ontario infants as young as six months in outbreak zones have been offered early vaccination.What this means going forwardWithout elimination status, measles may now be considered endemic in Canada — meaning the potential for sustained transmission rather than only occasional outbreaks.Vulnerable groups (infants too young to vaccinate, immunocompromised individuals) are at heightened risk.A public-health milestone has been lost, signalling the fragility of gains made through vaccination programs.The outbreak underscores the “prevention gap” — even in a wealthy country with broad immunization access, high-risk pockets persist,