The excitement for the 2026 FIFA World Cup™ is building, but alongside the anticipation, health officials are issuing important warnings. The Pan American Health Organization (PAHO) is calling on countries throughout the Americas to significantly step up their efforts to combat measles, especially as major global events like the World Cup are set to attract millions of travelers. The concern is clear: increased international travel combined with ongoing measles outbreaks creates a fertile ground for the highly contagious disease to spread rapidly. PAHO's recent Epidemiological Alert emphasizes the critical need for robust health strategies. This includes a thorough review of existing measles and rubella surveillance systems and vaccination coverage to pinpoint areas most vulnerable to new outbreaks. By proactively identifying weak spots, health authorities can implement targeted preventive measures, safeguarding public health during a period of heightened global mobility. ## Understanding Measles and Its Dangers Measles is much more than just a childhood rash; it's a serious and highly contagious viral infection that can lead to severe complications. Symptoms typically begin with a high fever, cough, runny nose, and red, watery eyes. A few days later, tiny white spots may appear inside the mouth, followed by the characteristic red or reddish-brown rash that starts on the face and neck, then spreads downwards. While many recover without issues, measles can cause life-threatening complications like pneumonia, encephalitis (brain inflammation), and even death, especially in young children and those with weakened immune systems. The virus spreads through airborne droplets from coughing or sneezing, making it incredibly easy to transmit, particularly in crowded environments. A single infected person can easily pass the virus to 9 out of 10 unvaccinated people they come into close contact with, highlighting its extreme contagiousness. ## Why Mass Gatherings Amplify Risk Events like the FIFA World Cup are magnets for international travelers, bringing together people from diverse corners of the globe. While this fosters cultural exchange and celebration, it also inadvertently creates perfect conditions for infectious diseases to cross borders and ignite new outbreaks. When large numbers of people from different epidemiological contexts – some with high vaccination rates, others with lower ones, and some even bringing active infections – congregate in a single location, the risk of rapid disease transmission skyrockets. This is precisely why PAHO is advocating for heightened vigilance, not just during the World Cup, but for all large-scale international gatherings. ## Essential Advice for Travelers: Before You Go For anyone planning to travel to areas where measles or rubella transmission has been documented, PAHO offers crucial guidance. The primary recommendation is to ensure full vaccination against measles and rubella. This means travelers aged six months and older should have received two doses of the measles-rubella (MR) vaccine, or be able to provide proof of immunity. Ideally, this vaccination should happen at least two weeks before departure to allow the body to build sufficient protective antibodies. For those unsure of their vaccination status, consulting a healthcare provider before travel is paramount. Additionally, all travelers should be well-informed about the tell-tale signs and symptoms of measles and rubella, which include fever, rash, cough, runny nose, conjunctivitis (red eyes), joint pain, and swollen lymph nodes. Knowing what to look for can prompt early action and prevent further spread. ## During Your Journey and Upon Return Should any traveler develop symptoms consistent with measles or rubella while abroad, immediate medical attention is essential. PAHO advises wearing a medical facemask to prevent airborne transmission, avoiding close contact with others, and refraining from visiting public places for at least seven days after the rash appears. These measures are critical to contain the virus and protect others. Upon returning home, it’s equally important for individuals who suspect they may have contracted measles or rubella to promptly contact their healthcare provider. Crucially, they should inform medical professionals about their recent travel history, as this information is vital for accurate diagnosis, proper treatment, and public health follow-up, including contact tracing to prevent secondary infections in the community. ## Strengthening Public Health Defenses Beyond individual traveler responsibility, PAHO is urging countries to bolster their public health infrastructure. This includes strengthening epidemiological surveillance in high-risk zones such as border crossings, airports, seaports, and locations hosting major international events. Active case-finding, where health workers actively look for potential cases rather than waiting for them to be reported, is crucial for early detection. Rapid investigation of suspected cases, maintaining highly trained rapid response teams, and enhancing international coordination for contact tracing and outbreak management are also vital components of an effective defense strategy. These coordinated efforts are essential to quickly identify and contain outbreaks before they spiral out of control. ## The Growing Threat of Measles Across the Americas and Globally The alarm raised by PAHO is not without reason. The world is experiencing a concerning surge in measles cases. Data from the World Health Organization (WHO) reveals a staggering 184,489 measles cases reported globally in the first five months of 2026, with over 100,000 confirmed. While the South-East Asia and Eastern Mediterranean regions account for significant portions, the Americas region alone contributes a substantial 19% to the global total. In the Americas, 20,521 confirmed cases and 25 deaths were recorded in 16 countries and one territory between January and May 2026. This represents a four-fold increase compared to the same period in 2025, and has already surpassed the total number of cases reported throughout all of the previous year. Mexico, with 10,920 cases and 13 deaths, and Guatemala, with 6,209 cases and 12 deaths, are particularly hard-hit. Other nations like Canada (1,018 cases), the United States (1,952 cases), and Peru (301 cases), along with Bolivia, Belize, Costa Rica, El Salvador, Honduras, Panama, and Uruguay, have also reported cases linked to ongoing outbreaks or importations. A common thread among these cases is that the majority occurred in unvaccinated individuals or those whose vaccination status was unknown, underscoring the critical role of immunization in preventing this resurgence. While a measles vaccination certificate is not an entry requirement under International Health Regulations (IHR), PAHO firmly reiterates that vaccination remains the single most effective measure to prevent transmission and protect public health against this highly preventable disease. The goal is to ensure communities remain protected and that the excitement of international events is not overshadowed by health crises.