COP30 in Belém: PAHO recommends yellow fever and measles vaccination for travelers – PAHO/WHO

Washington, DC, October 22, 2025 (PAHO/WHO) – Ahead of the 30th United Nations Climate Change Conference (COP30), scheduled for November 10-21, 2025, in Belém, Pará state, Brazil, the Pan American Health Organization/World Health Organization (PAHO/WHO) recommends that travelers, including heads of state, scientists, activists and civil society representatives among the expected 60,000 attendees from 198 countries: check your yellow fever and measles vaccination status before traveling.

Yellow fever is a serious mosquito-borne viral disease that can cause high fever, liver damage and, in up to 50% of severe cases, death. So far in 2025, the Americas have reported 294 human cases, including 121 deaths, in six countries: Bolivia, Brazil, Colombia, Ecuador, Guyana and Peru. Additionally, Costa Rica reported one imported case. Although no cases have been reported in the city of Belém this year, its location in the Amazon region, a permanent risk area, requires caution.

Measles, a highly contagious viral disease, has returned globally, with 177,469 cases reported worldwide and 12,163 in 10 countries in the Americas as of mid-October, primarily among unvaccinated people or people with unknown vaccination status. Canada currently reports the highest number of cases in the region, while Brazil recorded 35 cases during the same period, none of them in Belém.

Although Brazil does not require proof of vaccination against yellow fever or measles to enter the country, PAHO/WHO recommends the following:

• People who have not been previously vaccinated should consider receiving one dose of the yellow fever vaccine (recommended for people 12 months to 59 years old) at least 10 days before traveling, and the MMR vaccine (measles, mumps, rubella, for people 12 months and older) at least 15 days before traveling.
• For people 60 years of age and older, the yellow fever vaccine is recommended with caution and should only be considered after a personalized medical assessment of risks and benefits.
• Both vaccines can be administered on the same day, or at least four weeks apart if administered separately.

PAHO/WHO calls on the countries of the region to strengthen epidemiological surveillance, guarantee the availability of vaccines in health services and improve risk communication aimed at travelers and international delegations.

Health systems are also encouraged to monitor possible cases among COP30 attendees, both during the event and after they return home, paying close attention to symptoms such as fever and rash (measles) or yellowing of the skin and eyes (yellow fever).