Mosquitoes do not normally die after sucking a host's blood, as the blood is used for egg production. Biochemists at the University of Arizona discovered that it is possible to stop the digestion of blood, causing the mosquito to die after two days and preventing the spread of disease.
Only female mosquitoes suck blood. Although mosquitoes derive their energy and nutrients from sugary fluids, such as nectar and honeydew, their eggs require the abundance of protein found in blood. The saliva of a mosquito blocks clotting of the blood, allowing easier access. During feeding, a female mosquito can ingest her entire body weight in blood.