Smelly feet linked to malaria risk
Smelly feet may be a serious health hazard in parts of the world affected by malaria, new research suggests.
Mosquitoes that spread the disease are attracted to people whose feet are heavily covered with certain kinds of bacteria, scientists have discovered.
The bugs give off an odour that draws the insects in, thereby increasing the chances of being bitten.
However, individuals with many different kinds of bacteria on their feet seem to have some protection.
The findings, published in the online journal Public Library of Science ONE, could lead to new ways of preventing malaria and other insect-spread diseases by altering body odour.
Authors Dr Niels Verhulst, from Wageningen University in the Netherlands, and colleagues wrote: "Compounds that inhibit microbial production of human odour or manipulation of the composition of the skin microbiota may reduce a person's attractiveness to mosquitoes."
The researchers sampled sweat from the soles of the feet of 48 mostly Caucasian male volunteers aged 20 to 64.
Before the start of the study participants were told to refrain from drinking alcohol, eating garlic, onions or spicy food, taking a shower or using perfumed cosmetics. They were also told to wear special nylon socks provided by the research team for 24 hours before sampling.
In a series of experiments, the researchers tested the attractiveness of different samples to A. gambiae mosquitoes from Liberia, Africa, where malaria is endemic.
The degree to which mosquitoes homed in on the samples depended on the abundance and type of bacteria present. Levels of Staphylococcus bacteria were 2.62 times higher in samples from "highly attractive" individuals than from "poorly attractive" individuals.