Mosquitoes go through a four-stage life cycle: Egg, Larva, Pupa, and Adult.
After a female has fed (usually on blood), she lays eggs. Depending on the species, eggs can be laid directly on water, on the surface of an object containing water, or in a flood-prone area. Eggs hatch into mobile, microorganism-feeding larvae. Larvae then develop into non-feeding pupae. Pupae develop into flying male and female adult mosquitoes. Blood-feeding adult female mosquitoes can transmit pathogens that can cause diseases such as West Nile and Zika in humans. This entire process, from egg hatching to adult development, can take anywhere from 1-3 weeks.