Haemaphysalis longicornis: A tick of considerable veterinary importance, now established in North America

Haemaphysalis longicornis, the “Asian longhorned tick” (ALT), is native to eastern Asia and has spread to Australia, New Zealand, and several Pacific islands, where it is a threat to the health and welfare of wild and domestic animals (1,2). This tick is now established in the United States. Large numbers of all active life stages were collected from sheep, humans, and vegetation on a ranch in Hunterdon County, New Jersey, in October 2017 (3). From April to September 2018, numerous ALTs were collected from vegetation, domestic animals, wildlife, and humans in 8 additional States (4). Retrospective examination of tick collections revealed that populations were present in New Jersey as early as 2013 (5). Fortunately, this tick has not been detected in Canada; this was confirmed through re-examination of Haemaphysalis species held in the Canadian National Collection, Ottawa (Wayne Knee, Canadian National Collection of Insects, Arachnids and Nematodes, personal communication, 2018)