An article in the current issue of PLoS Biology
describes a study of Kenyan children and Anopheles gambiae
, a malaria-carrying mosquito. The researchers found that children infected at the most transmissible stage of malaria (the gametocyte stage) are more attractive to mosquitoes
than are uninfected children and those at less transmissible stages of disease. The parasite self-propagates by attracting vectors to itself, which is a really fascinating idea - what if HIV infection somehow made people sexier or increased their libidos?
It's not clear what exactly happens to make the infected kids more attractive to mosquitoes - some pheromone, or residue in sweat or what - but it reminds me of the race of beings in one of the later Ender's Game
books who communicated entirely by molecular emissions. Well, it does!