Ticks and Flies That Carry Animal Diseases

Last Modified: March 19, 2024

a bull receiving treatment to protect against tropical bont ticks — This bull is receiving a doramectin injection to protect it from tropical bont ticks.

Certain ticks and flies (also called vectors) can injure and transfer disease to people and animals and threaten American agriculture. APHIS has put in place measures to prevent the entry, establishment, and spread of exotic vectors. These safeguards include import inspections, testing, identification, surveillance, and targeted response and treatment strategies.

Asian longhorned ticks are aggressive biters. They can form large infestations on an animal, causing stress, reduced growth and production, and severe blood loss. This pest can also spread diseases that impact both animals and people.

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Tropical bont ticks are periodically detected in the U.S. Virgin Islands. These ticks cause painful wounds to livestock and wildlife. They are known to spread the bacterial disease heartwater.

Cattle fever ticks are important parasites of cattle because they can carry bovine babesiosis and anaplasmosis. APHIS and partners have confined this pest to a permanent quarantine zone along the Texas-Mexico border.

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The red sheep tick was detected in the United States in 2020 in Rhode Island. It has not been found anywhere else in this country. This pest can transmit several diseases to livestock.

New World screwworm is a serious livestock pest. It feeds on the living tissue of warmblooded animals. If untreated, it can cause deadly damage to animals and people.