The United States may lose its measles elimination status as soon as January, marking the sustained resurgence of a disease that had been eliminated from the country 25 years ago.
On Nov. 10, Canada lost its measles elimination status, after the Pan American Health Organization concluded that the country's recent measles outbreaks were connected and represented ongoing transmission lasting more than 12 months. Measles is considered eliminated in a country or region only when there are no outbreaks lasting longer than a year. Thus, to maintain "elimination status," any introductions of the disease from travel must be quashed before 12 consecutive months of spread.
