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Yellow fever - Region of the #Americas (#WHO D.O.N., May 16 '25)

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By G.M.

{Summary}

Situation at a glance

From 29 December 2024 and as of 26 April 2025 (with data for Ecuador updated as of 2 May 2025), a total of 212 confirmed human cases of yellow fever, including 85 deaths, have been reported to WHO by five countries in the Region of the Americas (case fatality rate (CFR) 40%). 

The cases have been reported in the Plurinational State of Bolivia, Brazil, Colombia, Ecuador and Peru. 

The 212 confirmed yellow fever cases reported so far in 2025 represent a threefold increase compared to the 61 confirmed cases reported in 2024. 

WHO is supporting affected countries in implementing coordinated actions to respond to the yellow fever cases and outbreaks. 

This includes: 

- enhancing preventive measures, 

- strengthening surveillance and case management, 

- improving risk communication and community engagement, and 

- implementing immunization activities. 

The current yellow fever situation in the Americas is driven by increased sylvatic transmission cycles. 

The occurrence of yellow fever cases outside of the Amazon basin, combined with high fatality, varying vaccination coverage across affected countries, and limited vaccine supply, contributes to the overall classification of yellow fever risk in the Region of the Americas, especially in endemic countries, as high. 

WHO emphasizes the importance of active surveillance, timely laboratory testing, cross-border coordination, and information sharing. 

Vaccination remains the primary means for the prevention and control of yellow fever. 

WHO continues to support countries in expanding vaccination coverage through routine immunization programs and mass vaccination campaigns to enhance population immunity and reduce the risk of outbreaks.

(...)

Source: World Health Organization, https://www.who.int/emergencies/disease-outbreak-news/item/2025-DON570

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