She has found, for instance, that the malaria parasite seems to alter the mosquitoes’ sense of smell so that they are even more attracted to smellier feet, swarming to worn socks like bees to a flower bed. “There is some evidence that some proteins in the head of the mosquito change somehow, and they have a role in the olfactory response of mosquitoes,” says Smallegange. It’s a devious mechanism that leads the malaria’s host to home in on potential victims, so that it can continue its life cycle in a human body.

— Dr Renate Smallegange, a medical and veterinary entomologist at Wageningen University in the Netherlands, quoted in The disgusting secrets of smelly feet at BBC.