In 2025, between the epidemiological week (SE) 1 and the SE 24 (from June 15), in the Americas region, 7 132 cas Decoe were confirmed, including 13 deaths, in Argentina (n = 34), in Belize (n = 34), in the plural state of Bolivia (n = 60), in Brazil (n = 5), in Canada (n = 3,170, including a death), in Costa Rica (n = 1 case), in Mexico (n = 2,597 cases, including nine deaths), case) and in the United States of America (n = 1,227, including three deaths). This total represents a multiplication by 29 compared to the 244 cases of measles notified during the same period in 2024.
The distribution of confirmed measles cases in the Americas region per week shows an increase in cases from week 3 of 2025, the maximum number of cases recorded in week 18 being linked to outbreaks in hesitant communities to be vaccinated in several countries in the region. According to information available on experienced cases, the most affected age group is that of 10-19 year olds (24 %), 1-4 year olds (22 %) and 20-29 year olds (19 %). However, the incidence rate is higher in children under one year (2.9 cases per 100,000 inhabitants), followed by the group of 1 to 4 years (2.3 cases per 100,000 inhabitants) and 5 to 9 years (1.4 cases per 100,000 inhabitants). With regard to vaccination history, 30 % of cases were not vaccinated and in 65 % of cases, this information was unknown or absent.
Au Canadabetween the SE1 and the SE23 of 2025, 3,170 cases of measles, a death of which were declared in nine provinces and territories: Alberta (n = 843), British Columbia (n = 12), Manitoba (n = 106), Northwest Territories (n = 1), Nova Scotia (n = 1), Ontario (n = 2,118, Congenital measles, born prematurely and having other serious medical complications not linked to the virus), Prince Edward Island (n = 2), Quebec (n = 36) and Saskatchewan (n = 51). In 2024, 177 cases had been detected in 2024. In 2025, 93% of cases were exposed in Canada, 1% are imported cases and 6% (n = 190) have an unknown or experimental source of exposure. As regards vaccination history, 85% were not vaccinated.
Most of the cases reported in 2025 are linked to an epidemic outbreak affecting several jurisdictions and affecting people who are not vaccinated in weakly covered communities that interact with each other. The epidemic began at the end of 2024. The epidemic came from an imported case which participated in an event in New Brunswick in October 2024, which people from several provinces attended. The majority of cases linked to this epidemic were not vaccinated (84 %) or had an unknown vaccination status (12 %).
To UNITED STATESBetween the 1st and 25th day of 2025, 1,227 cases of measles, including three deaths, were reported in 37 jurisdictions: Alaska, Arkansas, Arizona, California, Colorado, Florida, Georgia, Hawaii, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiane, Michigan, Minnesota, Missouri, Montana, Nebraska, New Jersey, New Mexico (including a death), New York City, New York State, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Dakota, Tennessee, Texas (including two deaths), Utah, Vermont, Virginie and Washington.
Of the total of cases, 89 % are associated with households (three cases or more), 23 households having been identified this year. An epidemic in the States of Texas, New Mexico and Oklahoma is the source of 69 % of the reported cases.
Regarding vaccination, 95 % of cases were not vaccinated. In the United States, ROR vaccination coverage in children has decreased in recent years, from 95.2 % in 2019-2020 to 92.7 % in 2023-2024.
Au Mexicobetween the SE1 and the SE24 of 2025, 2,597 cases of measles were confirmed, including nine deaths. Cases have been reported to Campeche (n = 6), Chihuahua (n = 2,417, including eight deaths), Coahuila (n = 13), Durango (n = 15), Guanajuato (n = 2), Guerrero (n = 5), Michoacán (n = 13), oaxaca (n = 4), Querétaro (n = 1) 1), San Luis Potosí (n = 1), Sinaloa (n = 2), Sonora (n = 78, including a death), Tabasco (n = 1), Tamaulipas (n = 12), Yucatán (n = 1) and Zacatecas (n = 20) (8).
With regard to vaccination history, 92.4 % (n = 2,396) were not vaccinated.
In Boliviabetween the SE1 and the SE24 of 2025, 60 cases of measles were confirmed, including an import linked, 95% (n = 57) being in the department of Santa Cruz. The first case reported in 2025 corresponds to a 14 -month -old child, with travel history in Brazil. The second case, reported on June 2, corresponds to a 22 -year -old woman who participated in a large -scale event with national and international participants, which took place in the municipality of Santa Cruz de la Sierra.
Regarding the history of measles vaccination, 80% of cases were not vaccinated or had a history of unknown vaccination, including 26 cases which correspond to people from low -level communities and who interact with each other.
Au Belizebetween the SE1 and the SE26 of 2025, 34 cases of measles were confirmed, 33 of which in the Cayo district. Of the total number of confirmed cases, four are imported and 30 are linked to import. The imported cases have a history of travel in Mexico between January and April 2025. Regarding the history of measles vaccination, none was vaccinated or had a history of unknown vaccination at the time of the diagnosis.
In Argentinebetween the SE1 and the SE24 of 2025, 34 cases of measles were confirmed in the autonomous city of Buenos Aires (CABA) (n = 13), the province of Buenos Aires (n = 20) and San Luis (n = 1), six of which are imported and 24 in connection with import. With regard to cases classified as imported, two are from Russia, one from Thailand, one from Mexico and two from England. With regard to import cases, the epidemiological survey and/or the genotyping of the National Reference Laboratory (LNR) made it possible to identify that 24 of the cases belong to the same chain of transmission as the cases imported from Russia.
Regarding the history of measles vaccination, in 21% (n = 7) of cases, vaccination was not appropriate because they had less than a year; 41% (n = 14) had a history of unknown vaccination or had not received a dose, 12% (n = 4) had received a single dose of ROR vaccine and 26% (n = 9) had received two doses of Ror vaccine.
Au BrazilBetween the SE1 and the SE22 of 2025, five cases of measles were confirmed in the federal district (n = 1 imported case concerning an adult woman who traveled to the United States, in Singapore, in the Philippines and Australia), in Rio de Janeiro (n = 2 cases corresponding to two non-vaccinated infants aged under 8 months), in São Paulo ( travel history) and at Rio Grande Do Sul (n = 1 imported case concerning an adult woman who has traveled to the United States).
Au Perubetween the SE19 and the SE24 of 2025, four cases of measles were confirmed in the province of Lima. Two cases imported from the United States and two imports related to health professionals.
Au Costa RicaBetween the SE1 and the SE24 of 2025, a case imported from measles was confirmed in the province of Guanacaste. It is an 18 -year -old non -vaccinated young woman who entered the country on May 3, 2025 from Canada.
Figure: geographical distribution of confirmed cases of measles by subnational level (in yellow) in the region of the Americas, 2025 (up to the SE25)
Source : PAHO. Epidemiological Update Measles in the Americas Region. 1 July 2025
Associated areas: United States, Canada, Mexico, Belize, Bolivia, Brazil, Costa Rica, Peru, Argentina
