How a brutal drought may have helped unleash yellow fever in Brazil

Mosquitoes thrive after rain, but drought can also alter behavior and raise disease risk

Three small gray monkeys with long striped tails sit in a row on a power line with lots of cords attached to a wooden pole. In the background is a forested area.

Computer simulations suggest that marmosets, such as these sitting on powerlines in urban Brazil, may have helped spark the country’s first yellow fever outbreak in decades when a severe drought sent forest animals searching for water in cities.

Anaid Cárdenas-Navarrete

Rain may bring disease-carrying mosquitoes.