Asian longhorned tick

Asian longhorned tick (ALHT)

Asian longhorned tick and its impact

Asian longhorned tick (Haemaphysalis longicornis) can infest a variety of mammals. Heavy ALHT infestations have been reported on cattle and white-tailed deer, and livestock and deer are thought to be their primary hosts. In its native range, it vectors several diseases for animals and humans. ALHT in the U.S. does not currently carry or vector any pathogens.

ALHT has been shown to carry Rocky Mountain Spotted Fever under laboratory conditions, but this has not been found in the field.

ALHT are unique among many other ticks because they can reproduce without a male. A female tick can lay up to 2,000 eggs without a male, meaning that one female can create a new population,


ALHT is a recent invader of the U.S. It was confirmed in the U.S/ in 2017 but has likely been here since 2010. As of April 2023, ALHT has not been detected in Illinois but has been found in Kentucky, Indiana, Missouri, and Tennessee.

A very small tick

Asian longhorned tick and it's regulation

There are currently no regulations in place for ALHT.

How to identify the Asian longhorned tick 

ALHT is a very small light brown tick. The adults are about the size of a sesame seed before feeding and about the size of a pea after a blood meal. Female ticks lay eggs in spring and early summer and when the larvae hatch, they climb plants and wait for a suitable host. They are host seeking through their larval and nymphal stages throughout the summer.

How to manage Asian longhorned tick

For both livestock and humans, tick checks are crucial for prevention of tick infestations and possible disease spread. There are pasture and lawn control measures that can reduce tick-bite risk. Weed control, low grass height, and general sanitation are good cultural control practices to prevent tick-bite risk. There are labeled insecticides for ALHT control in the environment as well as personal protective clothing that can be used to prevent tick-bites on humans.