Evidence is accumulating that Plasmodium-infected vertebrates are more attractive to mosquitoes than noninfected hosts, particularly when high levels of gametocytes are present. Changes in host odour have been suggested as a likely target for parasite manipulation because olfactory cues are crucial to mosquitoes in search of a bloodmeal host. This review discusses two routes that may lead to such changes: (i) direct emission of volatile products from malaria parasites, and (ii) changes in skin microbial composition that could lead to changes in the vertebrate odour profile. Here we synthesize what is known and suggest how further research can increase our understanding of the mechanisms of parasite manipulation of host attractiveness. Plasmodium-infected vertebrates are more attractive to mosquito vectors than are noninfected individuals.In humans, high levels of gametocytes are associated with a significant increase in attractiveness, suggesting that Plasmodium-induced attractiveness is highest when the chance of transmission is greatest. Plasmodium is associated with the emission of volatile organic compounds in in vitro cultures and in infected vertebrates. Plasmodium chabaudii-infected mice and P. falciparum-infected humans emit higher levels of volatile organic compounds that are known to be produced by skin bacteria, suggesting that changes in the skin microbiome upon Plasmodium infection may partly explain how malaria parasites manipulate host attractiveness.
- Skin microbiome