Biting midges, also commonly known as “no-see-ums” or “punkies”, are a group of small blood-feeding flies in the genus Culicoides. Biting midges can transmit serious animal pathogens including bluetongue virus (BTV), epizootic hemorrhagic disease virus (EHDV), and African horse sickness virus (AHSV). BTV and EHDV are widespread viruses that affect ruminant animals like cattle, sheep, and deer. Recent outbreaks of BTV in Europe and EHDV in the United States have resulted in considerable animal mortality and severe economic impacts to cattle or deer producers, respectively. AHSV is primarily limited to sub-Saharan Africa where it affects equids causing high mortality in horses and donkeys, with zebras serving as a reservoir of the virus.
Biting midges generally develop in organically enriched moist to semi-aquatic habitats such as wet animal manure, deep leaf litter, tree-holes, or manure-polluted effluent emanating from confined animal facilities. Most biting midge species become active toward dusk and may bite throughout the night. Only female biting midges feed on blood, using bladed mouthparts to cut into the host skin until blood flows from torn capillaries beneath the skin surface of the host. Biting sites on the host are often determined by the species of biting midge, with many midge species biting the host on the belly while other species prefer to attack near the head or ears.