While they are willing to feed on anyone, mosquitoes do have a preference for who they bite. Mosquitoes prefer people who have type O blood over those with any other type.

Mosquitoes feed from those with Type O blood whenever they have the chance. Their next preference is those with type B blood. They feed least often from those who have type A blood. Around 85 percent of people secrete a type of chemical that tells the mosquitoes what kind of blood they have. Mosquitoes feed much more often on those who secrete this chemical than on those who do not.