More than 10,000 cases, 18 of them fatal, have been reported across 10 countries in the Americas this year, with the pace of infections 34 times higher than a year ago, the Pan American Health Organization (PAHO) said today, urging countries to step up their vaccination, surveillance, and outbreak responses.
In a news release, PAHO said the outbreaks are mainly linked to low vaccination coverage, with 89% of cases occurring in people who are unvaccinated or have unknown vaccination status. Though the region saw a slight rise in measles, mumps, and rubella (MMR) vaccine coverage from 2023 to 2024, at 89% for the first dose and 79% for the second dose, the levels are still below the 95% level recommended to prevent outbreaks.
Daniel Salas, MD, MPH, executive manager of the Special Program for Comprehensive Immunization at PAHO, emphasized that measles is preventable with a vaccine that has proven to be very safe and effective. “To stop these outbreaks, countries must urgently strengthen routine immunization and conduct targeted vaccination campaigns in high-risk communities,” he said.
Mennonite groups affected in multiple countries
Canada has the highest total in the region, with 4,548 cases, followed by Mexico (3,911) and the United States (1,356). Paraguay is the latest country to confirm measles cases, with other affected countries being Bolivia, Argentina, Belize, Brazil, Peru, and Costa Rica.
Two genotypes are involved in the outbreaks, with one identified in outbreaks across eight countries, especially in Mennonite communities in Canada, the United States, Mexico, Belize, Argentina, Bolivia, Brazil, and Paraguay. Brazil’s outbreak is focused on members of a small Russian Orthodox community in Tocantins state.
In North America, Canada’s transmission persists, with Alberta, British Columbia, Manitoba, and Ontario reporting most of the recent cases. Mexico has launched a large vaccination campaign targeting 14 locations in Chihuahua state, the country’s main hot spot. PAHO said indigenous communities have been hardest hit, with a case-fatality rate 20 times higher than the rest of the population.
Concerns about measles elimination status
Measles surges and ongoing transmission have led to concerns about hot-spot countries losing their measles elimination statuses, which the United States has had since 2000. PAHO said the Americas interrupted measles transmission in 2016, a milestone that was unique at the global level. Venezuela and Brazil experienced endemic transmission in 2018 and 2019, respectively, but they regained their elimination statuses in 2023 and 2024.
“Keeping measles at bay in the Americas remains a challenge, as the virus continues to circulate widely in other parts of the world and vaccine-hesitant groups are spread throughout the region,” PAHO said. It noted that, of nearly 240,000 suspected and about 108,000 confirmed cases reported globally this year, the eastern Mediterranean region makes up the highest portion, at 35%, while Africa and Europe each account for 21%.
More cases in New Mexico, Idaho
The US Centers for Disease Control and Prevention (CDC) did not update its measles total this week and said it would resume reports as soon as possible.
Meanwhile, states continue to report cases. The New Mexico Department of Health yesterday reported 3 more measles cases in Santa Fe County, all involving unvaccinated residents. The new confirmations push the state’s 2025 total to 100 cases.
Miranda Durham, MD, New Mexico’s chief medical officer, said officials are grateful that state residents continue to be vaccinated to help slow the spread of the virus. “Without that, measles outbreaks are more likely to last longer and grow over time.” Since February 1, a total of 48,620 people have been vaccinated.
Idaho health officials reported a second measles case, this one in Bonneville County, which involves an unvaccinated child who became ill after contact with a confirmed case reported last week, which involved an international traveler. In a statement, Eastern Idaho Public Health said the latest case marks Eastern Idaho’s first since 1991.
The previous Idaho case, reported earlier this week, involved an unvaccinated child in Kootenai County, which was the panhandle’s first case since 1991.