MMWR Article Outlines Study of Newly Arrived Ticks
The Asian longhorned tick (Haemaphysalis longicornis) has been found in several U.S. states since it was first discovered here in New Jersey in August 2017.
The Nov. 29 edition of the Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report contains an article about CDC's work with public health, agricultural, and academic experts to understand the possible threat posed by the spread of a tick species that is indigenous to eastern Asia and is an important vector of human and animal disease agents. The Asian longhorned tick (Haemaphysalis longicornis) has been found in several U.S. states since it was first discovered here in New Jersey in August 2017, according to the article.
Since then, 45 counties or county equivalents in New Jersey and eight other states—Arkansas, Connecticut, Maryland, North Carolina, New York, Pennsylvania, Virginia, and West Virginia—have reported finding the tick on a variety of hosts, including people, wildlife, domestic animals, and in environmental samples.
"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. "In other parts of the world, the Asian longhorned tick can transmit many types of pathogens common in the United States. 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."
"The public health and agricultural impacts of the multistate introduction and subsequent domestic establishment of H. longicornis are not known," Beard and his co-authors write in the article. "At present, there is no evidence that H. longicornis has transmitted pathogens to humans, domestic animals, or wildlife in the United States. This species, however, is a potential vector of a number of important agents of human and animal diseases in the United States, including Rickettsia, Borrelia, Ehrlichia, Anaplasma, Theileria, and several important viral agents such as Heartland and Powassan viruses. Consequently, increased tick surveillance is warranted, using standardized animal and environmental sampling methods."
CDC reported it is now working with federal, state, and local experts representing veterinary and agricultural science and public health to:
- Determine the geographic distribution of Asian longhorned tick in the United States
- Determine the kinds of pathogens carried by Asian longhorned ticks in affected states that could infect people
- Determine what new laboratory tests are needed to detect pathogens that could be introduced or spread by these ticks in the United States
- Establish a clean colony (ticks with no pathogens) for studies
- Determine how frequently the Asian longhorned tick bites people and animals in the United States
- Determine effective prevention and control strategies