The Pan American Health Organization/World Health Organization (PAHO/WHO) is urging people traveling throughout the Americas to review their vaccination status for yellow fever and measles, as both diseases continue to pose ongoing health risks in the region.
Yellow fever remains a serious mosquito-borne illness capable of causing high fever, severe liver complications, and death in up to half of severe cases. As of 2025, six countries in the Americas have reported 294 human cases and 121 deaths: Bolivia, Brazil, Colombia, Ecuador, Guyana, and Peru. Costa Rica has also identified one imported case. PAHO notes that travel to or through areas with active transmission warrants heightened precaution.
Measles has made a global comeback due to declining vaccination coverage. Worldwide, 177,469 cases have been reported so far this year. The Americas account for 12,163 cases across 10 countries, primarily among unvaccinated individuals or those without proof of full immunization. Canada currently reports the highest number of cases in the region.
PAHO recommends the following for travelers:
* One dose of the yellow fever vaccine for people aged 12 months to 59 years at least 10 days before travel to risk areas.
* The MMR vaccine (measles, mumps, rubella) for everyone 12 months and older at least 15 days before travel.
* Adults 60 and older should consult their doctor on the risks and benefits before receiving the yellow fever vaccine.
* Both vaccines can be given on the same day, or four weeks apart if administered separately.
The agency is calling on countries to strengthen vaccine access, reinforce disease surveillance, and continue public education efforts, particularly targeting travelers and international groups moving across borders.
PAHO also encourages health providers to remain alert for possible imported cases, paying close attention to symptoms such as fever and rash (measles) or jaundice (yellow fever), not only during travel but after travelers return home.
Vaccination remains the most effective tool to prevent outbreaks and protect both local residents and visitors throughout the Americas.