Wildlife

Brazil’s response to a huge yellow fever outbreak: Kill the monkeys

A yellow fever outbreak is tearing through Brazil leaving thousands dead in its wake — thousands of monkeys, that is. Not only are monkeys susceptible to yellow fever, but local residents have begun pre-emptively killing monkeys, incorrectly assuming that they help spread the disease.

As the epidemic advances, rural towns are littered with monkey corpses falling from trees, terrifying villagers. One town in the southern state of Minas had to close down a park after 38 dead monkeys were found in its premises.

But, contrary to local lore, these primates don’t transmit the disease. In fact, they play a crucial role in preventing its spread. A dead monkey is often the first sign yellow fever has reached a new town, which can serve as an alarm bell for authorities directing vaccination campaigns. It’s a warning sign that allows health officials to monitor the disease before it hits humans.

Scientists are calling the monkey killings an environmental disaster. Howler monkeys have been hit the hardest, with more than 1,000 killed since January. As the disease spreads north, scientists are particularly worried about the endangered brown howler monkeys, which have already started to become infected and face the threat of extinction.