Asian Longhorned Ticks Are The Latest Bugs To Set Up Shop In CT

CONNECTICUT — If you are beginning to feel as though there is a headline about a new insect invasion every few weeks, you're not too far off the mark.

The Connecticut Agricultural Experiment Station reported the first established population of the Asian longhorned tick in Fairfield County this week. Haemaphysalis longicornis is an invasive species that was first discovered on a farm in New Jersey in 2017, raising public and veterinary health concerns, and has subsequently been found in at least 14 other states.

What's going on with these tick invasions? Goudarz Molaei, a research scientist who directs the CAES Passive Tick Surveillance and Testing Program, chalks it up to the weather, mostly.

"We don't have those harsh winters that we used to have in our state," Molaei said. "When these ticks get into our state, because of the environmental conditions, they are able to establish populations and stay here."

Molaei pointed to the recent invasion by the Gulf Coast ticks into the Nutmeg State.

"If that tick can survive winter in our state, you can imagine a number of other ticks can as well," Molaei said. "I think this is the tip of the iceberg of range expansion of ticks, mosquitoes and other vectors in the region, so this is going to sadly continue, and we have to be prepared."

We have limited resources to turn back the tide of an insect invasion once it drops its bags on our state's doorstep, but the Asian tick really, really doesn't play fair: It can breed through parthenogenesis, which — if you recall your sophomore science — means the females can reproduce without mating, making 1,000 to 2,000 eggs at a time.

"With this kind of biology, we are expecting to have an infestation that is unimaginable," Molaei told Patch.

Asian longhorned ticks are reddish-brown. Adult females are 2.7–3.4 mm long by 1.4–2.0 mm wide, whereas nymphs are 1.8 mm by 1.0 mm, and larvae are 0.6 mm by 0.5 mm. The ticks in the lab at CAES and scuttling around Fairfield County now are a long way from their native stomping grounds in the Korean Peninsula, Japan, and eastern regions of Russia and China. They're also a major livestock pest in Australia and New Zealand, where they were introduced before 1901.

The new-to-Connecticut insect is a known vector for the viral agent of severe fever with thrombocytopenia in humans, among other pathogens. Molaei said his team at CAES is closely monitoring the distribution and human biting activity of the ticks for their "potential involvement in transmission of exotic and local disease agents."

If there is anything good to report about the Asian longhorned ticks, it's that they appear to be less attracted to human skin compared with well-known native ticks such as the blacklegged tick, lone star tick and American dog tick, according to the Centers for Disease Control and Prevention.

"The potential is high for invasive ticks capable of transmitting pathogens of human and veterinary concern to become further established in new areas as environments continue to change," Molaei said. "Proper surveillance, interception and identification of exotic ticks are vital to protecting human and veterinary health."