The Pan American Health Organization (PAHO) is urging countries across the Americas to intensify vaccination, disease surveillance and outbreak response efforts as measles cases continue to rise across the region.
The warning comes as the Americas records its highest number of confirmed measles cases in more than two decades, with transmission still active in several countries.
Measles is highly contagious and spreads through the air when an infected person breathes, coughs or sneezes. Symptoms can include fever, cough, runny nose, conjunctivitis and a characteristic rash. Severe cases can result in complications such as pneumonia, encephalitis, blindness and death.
By the end of epidemiological week 28 on July 18, 2026, health authorities across the region had recorded 47,459 confirmed measles cases. A total of 44 deaths have been reported in three countries. The figure is more than three times the 15,011 cases recorded throughout 2025, when 32 deaths were also reported.
Guatemala, Mexico, the United States and Peru account for approximately 95 percent of confirmed cases reported in the region so far this year. Guatemala has recorded the highest number, with 30,371 cases and 26 deaths, followed by Mexico with 12,255 cases and 17 deaths. The United States has reported 2,260 cases, while Peru has recorded 1,277 and Canada 1,107.
PAHO continues to classify the public health risk associated with measles in the Americas as very high. The assessment takes into account ongoing outbreaks, gaps in vaccination coverage and the growing number of people susceptible to infection.
International travel and large gatherings are also contributing to the risk of the virus being introduced into new areas and spreading between countries.
While some of the region’s larger outbreaks have begun to slow, PAHO says transmission remains active in several countries. The organization has also noted cases emerging in new geographic areas and an increase in measles-related deaths compared with 2025.
PAHO’s Executive Manager of the Special Program for Comprehensive Immunization, Daniel Salas, stressed that continued vigilance is necessary to prevent further spread.
Salas noted that “Measles leaves no room for complacency” and further emphasized the need for high vaccination coverage, early detection of suspected cases and a rapid response to interrupt transmission.
PAHO is particularly concerned about young children who have not yet reached the age for their first vaccine dose, as well as unvaccinated and under-vaccinated populations. Indigenous communities, migrants, displaced people and others facing barriers to healthcare are also considered particularly vulnerable.
The organization is calling for countries to achieve and maintain at least 95 percent coverage with two doses of a measles-containing vaccine. PAHO says this level of coverage is critical to interrupt transmission, protect vulnerable populations and support efforts to restore the Americas’ measles elimination status.
The regional increase forms part of a wider global resurgence. World Health Organization data show that 186,168 measles cases had been reported globally by July 2026, representing a 12 percent increase compared with the same period in 2025.
PAHO has said that it will continue working with countries to strengthen surveillance systems, expand vaccination efforts, improve preparedness and response to outbreaks, and enhance public communication, particularly in areas where transmission and vaccination gaps remain.