The Asian Longhorned tick, Haemaphysalis longicornis, originates in East and Central Asia and has been known to menace cattle in New Zealand. The first tick of this species was discovered in the United States in 2017 and has now spread to 11 eastern states, including Connecticut. https://newsnetwork.mayoclinic.org/discussion/infectious-diseases-a-z-why-the-asian-longhorned-tick-is-more-than-a-menace/ Since this tick is relatively new to the US and could transmit harmful pathogens, experts are studying its potential effects and the USDA Department of Agriculture is trying to contain its spread as much as possible.

 

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Habits

 

The Asian longhorned tick is also known as the cattle tick, the bush tick, or the Asian tick. It parasitizes and spreads quickly among cattle, as well as other farm animals like sheep, horses, and pigs. This tick also likes to feed on birds.

 

An interesting characteristic that distinguishes the Asian longhorned tick from other species in Connecticut is that it’s capable of asexual reproduction. The female doesn’t require a male to become fertilized, as she’s able to produce and lay eggs all on her own. As a result, this tick may have the potential to spread much more rapidly than other species.

 

While many ticks distributed across the Northeast United States typically prefer forests and tall grass environments, it’s thought that Asian longhorned ticks favor short-grass meadows in either shade or sunshine. One reason for this belief is evidenced by the first human to be bitten by one of these ticks in the US – a man from Yonkers, NY, who was bitten presumably while he was on his lawn. http://www.cidrap.umn.edu/news-perspective/2019/06/first-us-human-bite-worrying-longhorned-tick-noted

 

Lifecycle

 

The full lifecycle of an Asian longhorned tick can last 6 months. Like many ticks, their full lifespan depends on their environment and if they are able to find a host. They also go through 3 phases after hatching – larva, nymph, and adult. It’s also common for this tick species to lie dormant in the winter months and become active again in the late spring and summer.

 

Larvae will feed on their hosts from 3-9 days, nymphs from 3-8 days, and adults from 7-14 days. In each phase of life, these ticks need a new host to take their necessary blood meal. Their development can be sped up in warmer temperatures and slowed down in cooler ones. Asian longhorned ticks also have a higher tolerance for dehydration than other tick species, so they can survive longer in the arid environments their preferred hosts are in.

 

When an adult female has her blood meal and becomes fully engorged, she can drop off her host and lay 2,000 eggs before she dies. And she can do so with or without fertilization from a male Asian longhorned tick.

 

Identification

 

Asian longhorned ticks are reddish-yellow in color, with 8 legs (as nymphs and adults). Females are slightly larger than males when unengorged. After taking a full blood meal, females expand massively. These ticks are also similar in size to the black-legged tick, a common tick found in Connecticut.

 

Two similar species of ticks that are already distributed in parts of the US are the rabbit tick and bird tick. The Asian longhorned tick differs from these two with the angle of its mouthparts. Since Asian longhorned ticks are a new invasive species to the United States, many non-experts are unable to identify them properly.

 

Associated Diseases

 

The Asian longhorned tick is a known vector in Asia for the bacteria Babesia gibsoni, Ehrlichia chaffeensis, and Powassan virus, which cause diseases in livestock, pets, and humans. Of the Asian longhorned ticks found in the US, though, it is still unknown if they could become vectors for these pathogens.

 

Babesia gibsoni causes canine babesiosis and Ehrlichia chaffeensis causes human ehrlichiosis. Experts are still studying the potential effects of these ticks in the US, to determine if they are capable of carrying the same diseases that have been confirmed in Asia. A particular concern for cattle and livestock is reduced milk production, as this was decreased by 25% in New Zealand and Australia. http://www.cidrap.umn.edu/news-perspective/2019/06/first-us-human-bite-worrying-longhorned-tick-noted

 

Final Thoughts

 

Asian longhorned ticks present a potential danger since much remains unknown about their behavior and capability to spread disease in the US. But it’s safe to say the measures you take against other tickborne diseases apply here – cover yourself with long sleeves and pants, tall socks, and closed-toe shoes when you go into high-grass and even low-grass areas. Using repellent when venturing outside is prudent, as is checking yourself and your animals for ticks upon returning home. The best defense is always prevention.