In August 2017, a population of Asian longhorned ticks (Haemaphysalis longicornis) was first found in the U.S. outside of a quarantine facility. It is a known serious pest of livestock in the Australasian and Western Pacific Regions where it occurs. It is an aggressive biter and frequently builds intense infestations on domestic hosts causing great stress, reduced growth and production, and exsanguination. As the tick can reproduce parthenogenetically (without a male), a single fed female tick can create a population. It is also a known/suspected vector of several viral, bacterial and protozoan agents of livestock and human diseases. U.S.-collected Asian longhorned ticks have now been shown to vector Theileria orientalis Ikeda in the laboratory to calves.
For more information, please see our fact sheet on Cattle Theileriosis. For more information on the Asian longhorned tick or other related exotic ticks see our Asian Longhorned Tick Fact Sheet, ALHT Response Plan, ALHT Story Map, ALHT Situation Reports, or see our Red Sheep Tick (Haemaphysalis punctata) Fact Sheet.
In 2016, the United States had its first outbreak of New World Screwworm (NWS) in over 30 years. The NWS fly’s larval (maggot) stage feeds on the living tissue of warm blooded animals. The larvae were found infesting the endangered key deer in the Florida Keys prompting a multiagency response involving the release of sterile flies. More information on the fly, response, and lessons learned can be found here.
Bont and Tropical Bont Ticks (Ambylomma hebraeum and Amblyomma variegatum) Both ticks have large mouthparts that result in large, painful wounds. They are also vectors of Heartwater, a bacterial disease caused by Ehrlichia ruminantium. The tropical bont tick may serve as a vector for Nairobi sheepdisease (NSD), a virus (family Bunyaviridae) which primarily affects sheep and goats in East and Southern Africa. People may contract NSD, but it causes only a mild, influenza-like illness. Additionally they may vector Dermatophilosis which is a skin disease caused by the bacterium Dermatophilus congolensis. Standard operating procedures for NSD, Heartwater, and bont ticks may all be found here.