Measles outbreaks in the Americas: PAHO calls for strengthened vaccination and surveillance – PAHO/WHO

Washington, DC, March 3, 2025 (PAHO) – The Pan American Health Organization (PAHO) has issued an epidemiological alert due to an increase in measles cases in several Americas countries. From the epidemiological week 8 of 2025 (February 21, 2025), 268 measles cases have been confirmed, including a death, in Argentina, Canada, Mexico and the United States. This represents a significant increase compared to the same period in 2024, when 60 cases were reported during the first eight weeks of the year.

Although the region was reverified as measles free in 2024, measles remains a threat due to its continuous circulation in other regions of the world, which increases import risk through travelers and the existence of non -immunized population groups that continue to be vulnerable. Of the 268 cases confirmed in 2025, 69% were in people over 5 years of age.

Last year, 17,887 suspicious measles cases were reported in the region, of which 464 were confirmed, with a notable proportion of these in adolescents and young adults. In particular, 63% of the cases confirmed in 2024 had not been vaccinated, highlighting the gaps in immunization coverage.

Pah urgently calls the countries and territories of the Americas to intensify their efforts of vaccination and epidemiological surveillance, as well as to strengthen their rapid response capacity to contain and control outbreaks. Recommendations include intensifying vaccination campaigns, especially in high -risk areas, and improving surveillance to detect suspicious cases of the disease in a timely manner.

It is also recommended that vaccination coverage with two doses of MMR vaccine (measles, rubella and papers) remain above 95%, reaching all populations, with special emphasis on young children and adults, which constitute a significant portion of the cases.

The risk of measles outbreaks is due in part to factors such as the global circulation of the virus (more than 320,000 cases of confirmed measles were informed last year, according to WHO data, low vaccination coverage, greater mobility of people in the region and the similarity of measles symptoms to other diseases such as dengue, which could make the correct identification difficult.

Paho remembers that the elimination of measles syndrome, rubella and congenital rubella remains a public health priority for the region. To this end, it is essential that all countries work together to close the immunity gaps and make sure that no one is without protection against this highly contagious and serious but preventable disease.

The organization continues to monitor the situation and working closely with the countries of the region to support its efforts to vaccine, surveillance and rapid outbreaks to prevent the propagation and reintroduction of measles and protect the health of the entire population.