As the 2026 FIFA World Cup and a wave of other large-scale international mass gatherings approach across the Americas, regional health leaders are sounding a urgent call to action: countries must shore up measles surveillance, expand vaccination coverage, and refine rapid response protocols to counter ongoing outbreaks of the highly contagious disease across the region. This warning came in an official Epidemiological Alert published by the Pan American Health Organization (PAHO) on May 29, which outlines a series of actionable steps public health authorities can take to mitigate the risk of large-scale transmission during high-profile events. The alert notes that rising community transmission of measles combined with a surge in cross-border international travel creates ideal conditions for the virus to spread rapidly when thousands of visitors from across the globe gather for major events.
In the specific context of the 2026 FIFA World Cup and other upcoming mass gatherings, PAHO advises all host and neighboring countries to boost the sensitivity of their existing disease surveillance systems by rolling out active case-finding protocols. These efforts are designed both to document the absence of circulating measles and rubella in high-traffic areas and to ensure accessible information and vaccination services are available to all incoming and outgoing travelers.
To cut the risk of international virus spread during the 2026 tournament, PAHO has issued clear guidance for traveler vaccination protocols: all people aged six months and older who cannot provide official proof of full two-dose vaccination or existing immunity to measles and rubella should receive an additional dose of the combined vaccine at least two weeks before traveling to regions with documented ongoing transmission. Beyond vaccination, the organization also recommends that public health systems provide all departing travelers with clear educational resources on the most common signs and symptoms of measles and rubella, which include fever, widespread rash, cough, nasal congestion, conjunctivitis, joint pain, and swollen lymph nodes.
PAHO guidance also covers protocols during travel and post-arrival: travelers who develop symptoms consistent with measles or rubella while away from home are advised to seek immediate medical attention, wear a well-fitting medical face mask at all times, avoid close contact with other people, and stay away from crowded public spaces for a full seven days after the rash first appears to limit secondary spread. After returning to their home countries, travelers who suspect they may have contracted the virus are encouraged to reach out to a healthcare provider immediately and disclose their recent travel history to help enable fast diagnosis and contact tracing.
Beyond traveler guidance, PAHO is calling on national governments to strengthen routine epidemiological surveillance in high-risk sites across the region, including border crossings, international airports, seaports, and the venues that will host the 2026 World Cup and other major events. The alert specifically recommends expanding active case-finding efforts, ensuring all suspected cases receive full epidemiological investigation within 48 hours, maintaining fully trained and resourced rapid response teams, and strengthening cross-border coordination for international contact tracing and collaborative outbreak response when clusters are detected.
This public health alert comes at a time of sustained, alarming growth in measles cases both across the Americas and around the globe. According to data from the World Health Organization (WHO), between January 1 and May 13, 2026, 184,489 suspected measles cases were reported by 155 WHO Member States, with 100,239, or 54.3%, of these cases ultimately confirmed through laboratory testing. The WHO South-East Asia Region accounted for 29% of all global reported cases, followed by the Eastern Mediterranean Region at 21%, while the African Region and the Region of the Americas each made up 19% of the global total.
In the Americas specifically, 20,521 confirmed measles cases and 25 measles-related deaths have been recorded across 16 countries and one territory between the first and 20th epidemiological weeks of 2026. This figure marks a fourfold increase compared to the 5,123 cases recorded during the same period in 2025, and has already exceeded the total number of cases reported across the entire region for all of 2025.
As of the latest data, Mexico has confirmed 10,920 cases and 13 deaths so far in 2026, while Guatemala has reported 6,209 cases and 12 deaths. The United States has recorded 1,952 confirmed cases, while Canada has reported 1,018. Peru has logged 301 confirmed cases, and smaller numbers of cases tied to local outbreaks or imported infections have also been reported across Bolivia, Belize, Costa Rica, El Salvador, Honduras, Panama, and Uruguay.
PAHO officials emphasize that the vast majority of all confirmed measles cases across the region have occurred among people who were unvaccinated, or whose vaccination status could not be officially verified. The organization notes that growing volumes of international travel and ongoing widespread transmission make it clear that maintaining robust disease surveillance systems and ensuring all travelers are fully protected against vaccine-preventable diseases before they attend large international events is critical to preventing larger outbreaks.
In closing, PAHO reminded national health authorities that under the binding International Health Regulations, a measles vaccination certificate cannot be required as a condition of entry for international travelers. Even so, the organization stressed that widespread vaccination remains the single most effective intervention to stop measles transmission, protect vulnerable communities, and safeguard public health during major global events.