Attraction of Anhidrotic Subjects to Mosquitoes

Two anhidrotic individuals were tested for attractiveness to mosquitoes (Aedes aegyptiL). Attractiveness was evaluated by two methods: (1) by recording the time when 50% of exposed mosquitoes probed on the bottom of a cage held over the forearm probing time-50 (PT-50) technique and (2) by placing five mosquitoes in a similar cage held over the forearm and recording from the instant of first exposure the number of mosquitoes probing continuously for a period of ten minutes (continuous probing technique). The PT-50's on the forearms of these subjects were significantly higher than the PT-50's of controls (P<0.01) but the palm where the subject sweats was normally attractive. It is suggested that the low attractiveness of these anhidrotic individuals relates to the lack of sweat in their skin and the application of water releases substances attractive to mosquitoes.