The Pan American Health Organization is calling for countries across the Americas to ramp up vaccination and surveillance against yellow fever, having recorded an eightfold rise in cases of the highly fatal disease in the first 20 weeks of 2025.1
At least 221 cases of yellow fever and 89 deaths have been detected so far this year, prompting particular concern because most infections were reported outside the Amazon region, where the disease is endemic.
The Pan American Health Organization, the World Health Organization’s (WHO) regional office for the Americas, said that the spread of the virus far from the rainforest was raising concerns about urban contagion “that could lead to explosive outbreaks and onward spread.”
As a result WHO has upgraded the disease’s risk level to high, noting the high fatality of yellow fever virus in tandem with vaccine shortages and “the …
