There's a New Tick in Town
Date posted: Wednesday, August 18, 2021
Blog poster: NEHA's Vector Program Committee
There's a New Tick in Town
The Asian longhorned tick, Haemaphysalis longicornis, is native to East Asia and has spread to Australia and New Zealand. In 2010 it spread to the United States. The tick had been mistakenly identified as a rabbit tick, Haemaphysalis leporispalustris, and was not identified correctly until 2017 when multiple species were identified from a pasture in New Jersey. In the United States, these ticks have been documented in at least 16 states, mainly along the east coast. As of July 27, 2021, longhorned ticks have been found in Arkansas, Connecticut, Delaware, Kentucky, Maryland, New Jersey, New York, North Carolina, Missouri, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Virginia, and West Virginia. In other areas around the world where this tick lives, it tends to live in meadows and grassy areas near forests.
Asian longhorned ticks have been found on pets, livestock, wildlife, and people. One reason this tick is so successful is that the female ticks can lay eggs and reproduce without mating. Because of this, it multiplies rapidly, and thousands of ticks can be found together in grass or shrubs or on an animal. Compared with well-known native ticks (such as the blacklegged tick, lone star tick, and American dog tick), the Asian longhorned tick appears to be less attracted to human skin. However, in countries where this tick is normally found, they have been found to transmit disease to both people and animals. They are a major livestock pest and can transmit bovine theileriosis and babesiosis infection in animals. Asian longhorned ticks collected in Asia have also been found carrying pathogens similar to some of those that occur in the US, like the bacteria that cause anaplasmosis and ehrlichiosis, the parasite that causes babesiosis, and the Powassan virus. One recent experimental study found that this tick is not likely to contribute to the spread of Lyme disease bacteria in the United States. Another recent laboratory study found that this tick has the ability to carry and spread the bacteria that causes Rocky Mountain spotted fever (Rickettsia rickettsii). This bacterium has not yet been found in these ticks in nature, but research is ongoing. "The full public health and agricultural impact of this tick discovery and spread is unknown," said Ben Beard, Ph.D., deputy director of CDC's Division of Vector-Borne Diseases. "We are concerned that this tick, which can cause massive infestations on animals, on people, and in the environment, is spreading in the United States."
- A pictorial key to differentiate the recently detected exotic Haemaphysalis longicornis Neumann, 1901 (Acari, Ixodidae) from native congeners in North America, ZooKeys | Webpage
- What you need to know about Asian longhorned ticks - A new tick in the United States, CDC | Webpage
- Reports of Haemaphysalis longicornis in the United States, University of Georgia | Webpage
- The Asian Longhorned Tick, USDA | Webpage
- Asian Longhorned Tick Resources, USDA | Webpage
- First glimpse into the origin and spread of the Asain longhorned tick, Haemaphysalis, longicornis, in the United States, Wiley Online Library | Webpage
- The Longhorned Tick, Tennesee Ticks | Webpage
- Vectors and Public Health Pests, NEHA | Webpage
This blog is brought to you by NEHA's Vector Program Committee. Special thank you to Rosmarie Kelly.