ARS | Publication request: Partial blood meal, carbohydrate availability, and blood-feeding postponement effects on human host avidity and DEET repellency in Aedes albopictus (Diptera: Culicidae)

Submitted to: Experimental Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 22, 2009
Publication Date: N/A

Interpretive Summary: A female mosquito interrupted from blood feeding remains hungry, seeks the same or another host, and attempts to feed until no longer host avid. This process increases the potential for disease transmission to several hosts by the same mosquito. Two factors thought to affect mosquito hunger during this time are the interval between host contacts and carbohydrate availability. In this study, ARS and university scientists determined the effects of partial blood meal(s) combined with carbohydrate availability and postponement of host contact on host avidity and DEET repellency in the Asian tiger mosquito. Neither the number nor the source of partial blood meals was found to affect host avidity, whereas hunger decreased with time between host contacts and the absence of carbohydrate sustenance. The latter two factors also increased the repellency of DEET. The results showed that postponement of blood feeding and the absence of carbohydrate sustenance reduce human host avidity in mosquitoes but increase the effectiveness of repellents containing DEET.

Technical Abstract: Host avidity and DEET repellency were measured in partially blood fed Aedes albopictus (Skuse) provided 10% sucrose in water, water, or neither when access to a human host was postponed for 1 to 72 h after a partial blood meal. Carbohydrate availability and post-feeding time influenced host avidity but partial blood meal effects were not significant. Mean host avidity declined significantly between hours 1 and 6 (range: 50-18%) but increased significantly between hours 24 (54%) and 72 (68%) after a partial blood meal. Females provided sucrose solution and females denied sucrose or water were the least (29%) and most (39%) host avid regardless of other treatment effects. The longest and shortest DEET protection times were against females provided sucrose (8.5 h) and denied sucrose or water (7.3 h) respectively. Denial of carbohydrate sustenance significantly increased host avidity and DEET repellency in partially blood fed female Ae. albopictus, whereas sucrose availability led to reduced host seeking activity and decreased repellency of DEET.