Yellow fever cases rising in the Americas: PAHO warns

The Pan American Health Organization (PAHO) has issued a new epidemiological alert in response to an increase in yellow fever cases in the Americas during the initial months of 2025. From January to March 22, 2025, 131 cases in humans were confirmed, resulting in 53 fatalities, predominantly in Bolivia (1 case, 1 death), Brazil (81 cases, 31 deaths), Colombia (31 cases, 13 deaths), and Peru (18 cases, 8 deaths), with cases reported beyond the traditionally affected Amazon region. Of particular concern are the cases reported since October 2024 in the department of Tolima, Colombia, and those reported in the state of São Paulo, Brazil, with 34 cases and 19 deaths, respectively. These figures are of concern due to their proximity to densely populated urban centres. Most cases have been observed in individuals who have not received the vaccine. The increase in cases and their geographical spread highlight the need to strengthen surveillance, prevention, and control measures to contain the disease, especially through the strengthening of the vaccination campaign, aiming for coverage rates above 95%. It is a matter of concern that yellow fever, which is endemic in 13 regional areas of the Americas, has caused 9,591 human cases and 3,444 deaths since 1960.