Asian longhorned tick confirmed in Maine, 25th U.S. state

Maine has confirmed the presence of an invasive Asian longhorned tick, marking the 25th state to report the species and the farthest northeast the pest has been found in the United States. The University of Maine and state conservation officials said the tick was confirmed in July. The tick is native to eastern Asia and can carry diseases that affect humans and livestock, including tickborne infections such as spotted fever. Public health officials say ongoing tick surveillance is essential to track its spread as conditions in the region change.

The specimen found in Maine was juvenile, meaning it could not reproduce yet. The species is known to have two forms, including a parthenogenetic female that can lay eggs without mating, a trait that can enable rapid population growth if a single tick establishes itself. Field surveillance did not identify additional specimens in the surrounding area after the initial finding. Researchers say the Maine discovery underscores the importance of monitoring invasive ticks as they move into new territories and as climate conditions shift.

Griffin Dill, director of the UMaine Extension Tick Lab, said the finding underscores the critical importance of continued tick surveillance in Maine and that authorities are closely monitoring the situation and coordinating with state and federal partners. Asian longhorned ticks feed on a broad range of hosts, including cattle and humans, and can carry pathogens that threaten both health and agriculture. Officials note that in Asia the virus behind some tickborne illnesses carries a higher fatality rate, but in the United States the tick has been linked more to livestock deaths than to confirmed human illnesses so far.

Experts say climate change is expanding tick habitats by warming average temperatures and lengthening active seasons, allowing these arachnids to thrive in places where they previously could not survive. The Northeastern United States, which already contends with the deer tick that spreads Lyme disease, is watching for shifts in tick populations that could affect both public health and cattle industries. Public health agencies advise people to guard against bites by performing thorough tick checks after outdoor activity, avoiding overgrown vegetation, wearing protective clothing, and using repellents where appropriate. If a tick attaches to skin or a pet, remove it promptly with fine-tipped tweezers by grasping the tick as close to the skin as possible and pulling upward with steady, even pressure. Do not twist the tick as you pull. After removal, wash the area with soap and water and disinfect the bite. The tick should be kept in a sealed container for identification by a physician or veterinarian.