85 Yellow Fever Fatalities in the Americas Reported in 2025

Researchers believe the yellow fever virus has existed in the Region of the Americas since the 17th century and is now considered one of the most dangerous mosquito-transmitted infectious diseases.

According to the World Health Organization (WHO, DON570), as of May 16, 2025, the YF virus has become endemic in tropical areas of 13 countries in the Americas.

During 2025, five countries in the Americas reported 212 confirmed human cases of yellow fever, including 85 deaths (CFR 40%).

The YF cases were reported in the Plurinational States of Bolivia, Brazil, Colombia, Ecuador, and Peru.

The WHO writes that the 'occurrence of yellow fever outside of the Amazon basin contributes to the overall classification of YF risk in the Americas, especially in endemic countries, as high.'

WHO emphasizes that vaccination remains the primary means for preventing and controlling yellow fever.

The WHO continues to support countries in expanding Sanofi Pasteur YF-VAX® vaccination coverage through routine immunization programs and mass vaccination campaigns, enhancing population immunity and reducing the risk of outbreaks.

In the United States, the CDC recommends yellow fever vaccination at least ten days before visiting outbreak areas. YF vaccination appointments are at travel clinics and pharmacies in May 2025.