Mexico’s Measles Cases Increase; Region Loses Measles-Free Status

Mexico is reporting a continued rise in measles cases, as national and regional health authorities reassess containment efforts. Meanwhile, the Americas confront the loss of their measles-free status after the Pan American Health Organization (PAHO) confirmed in early November that the region no longer meets the criteria for the elimination of endemic transmission, following sustained outbreaks across several countries.

According to Mexico’s latest epidemiological update, as of Nov. 19, 2025, the country has registered 5,299 accumulated measles cases. Health authorities define a probable case as any person of any age presenting fever and maculopapular rash, along with symptoms such as cough, coryza, conjunctivitis, or lymphadenopathy. Confirmation occurs through laboratory analysis by the National Institute of Epidemiological Diagnosis and Reference (InDRE) or by epidemiological linkage to a laboratory-confirmed case.

Data indicates that 27 states and 150 municipalities in Mexico have reported confirmed infections. The first confirmed case of the year was notified in epidemiological week (EW) five. Preliminary figures show 190 probable and 20 confirmed cases in EW 46, and 23 probable cases in EW 47. Cases affect both sexes nearly equally. Children aged 0 to four years represent the largest group, with 1,355 cases, followed by adults aged 25 to 29 and those between 20 and 24. The highest incidence rate is also concentrated among children under four.

Measles remains one of the leading causes of mortality among children globally, according to the World Health Organization. The virus spreads through airborne particles expelled from the nose and mouth of an infected person, and can affect individuals at any age if they lack immunity. Early symptoms typically include a fever of at least three days, cough, runny nose, and conjunctivitis. Severe cases in people with weakened immune systems may progress to pneumonia. 

Vaccination continues to be the primary method of prevention. Mexico’s Universal Vaccination Program recommends the measles, mumps, and rubella (MMR) vaccine for children and the dual measles-rubella vaccine for adolescents and adults who have not been immunized.

Mexico’s Minister of Health, David Kershenobich, says that the outbreak is being contained and that some states have reported days without new cases. However, opposition legislator Éctor Jaime argues that the scale of the outbreak remains significant, noting that no other country in the continent, except Canada and the United States, has accumulated numbers this high. As of Nov. 7, the America’s region had reported 12,596 confirmed measles cases across 10 countries, a 30-fold increase compared to 2024, with about 95% of cases concentrated in Canada, Mexico, and the United States.

PAHO’s decision to revoke the region’s measles elimination status followed a meeting of the Regional Commission for Monitoring and Verification of the Elimination of Measles, Rubella, and Congenital Rubella Syndrome, held in Mexico City from Nov. 4–7, 2025. The organization cited ongoing transmission and rising case numbers as key factors in its determination.

“We must restore the use of existing vaccines to prevent resurgences of diseases we previously thought were under control, like measles,” says Rodrigo Romero, Coordinator, Mexican Association of Vaccinology, to MBN.