PAHO calls for regional action as the Americas lose measles elimination status – PAHO/WHO

Washington, DC, November 10, 2025 (PAHO) –The Pan American Health Organization (PAHO) announced today that the Region of the Americas has lost its verification as free of endemic measles transmission.

The decision follows the conclusion of the PAHO Regional Commission for Surveillance and Reverification of the Elimination of Measles, Rubella and Congenital Rubella Syndrome, which met in Mexico City from November 4 to 7, 2025 to review the epidemiological situation throughout the region. The Commission determined that endemic measles transmission has re-established in Canada, where the virus has been circulating for at least 12 months.

As a result, the Americas, which was the first region in the world to eliminate measles twice, has now lost its measles-free status. All other countries continue to maintain their measles elimination status.

“This loss represents a setback, but it is also reversible,” said Dr. Jarbas Barbosa, Director of PAHO. «Until measles is eliminated worldwide, our Region will continue to face the risk of reintroduction and spread of the virus among unvaccinated or undervaccinated populations. However, as we have demonstrated before, with political commitment, regional cooperation and sustained vaccination, the Region can once again interrupt transmission and regain this collective achievement.»

Current situation

As of November 7, 2025, 12,596 confirmed cases of measles have been reported in ten countries (approximately 95% of the Region’s cases in Canada, Mexico and the USA), a 30-fold increase compared to 2024. Twenty-eight deaths have been recorded: 23 in Mexico, 3 in the United States and 2 in Canada.

There are active outbreaks in Canada, Mexico, the United States, Bolivia, Brazil, Paraguay and Belize, mostly caused by imported cases. Transmission has mainly affected poorly vaccinated communities, and 89% of cases have occurred in unvaccinated people or in people whose vaccination status is unknown. Children under 1 year old are the most affected, followed by those between one and four years old.

The measles outbreak in Canada began in October 2024 in the province of New Brunswick and has since spread across the country, with more than 5,000 confirmed cases reported nationwide. Although declining, transmission persists in Alberta, British Columbia, Manitoba and Saskatchewan.

Measles is very contagious. A single infected person can transmit it to up to 18 other people. Serious complications can include pneumonia, encephalitis, blindness and death. Outbreaks also disrupt daily life and put additional pressure on health systems.

Vaccination remains the most effective means of protection. In the last 25 years, the measles vaccine has prevented more than six million deaths throughout the American continent, and an estimated 15 million deaths in the last 50 years. However, in 2024, regional coverage for the second dose of the measles, mumps and rubella (MMR2) vaccine averaged 79%, well below the 95% needed to prevent outbreaks. Furthermore, only 31% of countries reached coverage of 95% or more for the first dose, and only 20% reached that level for the second dose.

PAHO response and recommendations

PAHO continues to provide technical support to countries to strengthen surveillance, laboratory diagnosis, outbreak response, and vaccination campaigns. Experts have been sent to Mexico, Argentina and Bolivia, and the organization is monitoring risks in Belize, Brazil and Paraguay.

Dr. Barbosa emphasized: «Every case we prevent, every outbreak we stop saves lives, protects families and makes communities healthier. Today, instead of lamenting the loss of a regional status, we call on all countries to redouble their efforts to strengthen vaccination rates, surveillance and timely response to suspected cases, reaching every corner of the Americas. As a Region, we have eliminated measles twice. We can do it a third time.»

RVC strongly encourages countries to:

• Continue to strengthen surveillance, immunization, and rapid outbreak response activities for each suspected case.
• Expand and consolidate electronic vaccination records in all countries, following the guidelines established by PAHO.
• Maintain sustainable laboratory surveillance by allocating sufficient financial and human resources.
• For suspected cases with clinical and epidemiological risk factors and a negative measles IgM result (with samples collected 0 to 3 days after rash onset), perform a PCR test to confirm or rule out infection.
• Implement all recommendations down to the local level.
• Closing of the document outbreak after the Regional Framework guidelines.

Thinking about the future

The Americas have faced setbacks before, including the temporary loss of measles elimination status in Venezuela (2018) and Brazil (2019). The region regained elimination status in 2024 through coordinated regional action.

To regain measles elimination status, a country must demonstrate interruption of endemic transmission for at least 12 consecutive months, supported by comprehensive vaccination, surveillance, and outbreak response data.

Canada will now present and implement an action plan within the PAHO regional framework, focused on increasing immunization coverage, strengthening surveillance systems and ensuring rapid response to outbreaks to stop endemic transmission and regain measles elimination status.

“Cooperation, solidarity and science are stronger than any virus, because when we work together, we protect the health and lives of all people in the Americas,” concluded Dr. Barbosa.