Yellow Fever's Fatal Resurgence in the Americas

In just the first three months of 2025, 131 cases and 53 related fatalities have been reported in the Region of the Americas, more than double the total for all of 2024.

According to the Pan American Health Organization, Brazil, Colombia, and Peru have been the most impacted countries.

Particularly concerning are the new cases reported since October 2024 in the department of Tolima, Colombia, which indicates the virus is appearing in areas not previously affected in past years. 

What's driving this surge, and how can we protect ourselves?

Listen to the PAHO Let's Talk About Health podcast to discover the keys to confronting this growing threat.

While two approved yellow fever vaccines (YF-VAX, Stamaril) are available at travel clinics and pharmacies, maintaining high immunization rates is essential.

According to the U.S. Centers for Disease Control and Prevention (CDC), yellow fever vaccination is recommended for people aged nine months or older who are traveling to or living in areas at risk for the YF virus.

A study published in April 2025 was the first to examine vaccination effectiveness in children.

These researchers wrote, 'Current recommendations assuming lifelong protection from a single dose of the YF vaccine do not appear to provide sufficient protection for children in high-risk areas.'

As of April 15, 2025, the CDC has issued Travel Health Advisories regarding yellow fever risks and recommends prospective travelers speak with a vaccine expert at least one month before visiting an at-risk area.