Invasive Asian tick on Cape’s doorstep



Concern for entomologists is how quickly it could spread.

BARNSTABLE — Barnstable County officials are waiting to see if an invasive tick species that has made its way from overseas to New York state will cross the bridges to Cape Cod.

Known as the Asian or longhorned tick, the arthropod that sickens livestock in its native Asia has been found in eight states, including New York and Pennsylvania, since being pulled off a woman shearing sheep in New Jersey last year.

“It’s on our doorstep. But it’s not time to push the panic button,” said Larry Dapsis, deer tick program coordinator and entomologist with the Cape Cod Cooperative Extension.

The ticks reproduce asexually in a process known as parthenogenesis, which gives the species the opportunity to expand more quickly than other species, Dapsis said.

The longhorned tick can transmit diseases to livestock and cause lowered milk production in dairy cows and blood loss in calves.

“They can drain a lot of blood and kill young animals,” Dapsis said.

But he said the main concern of local entomologists is whether the longhorned tick will pick up diseases transmitted by the area’s blacklegged ticks and become another vector for illnesses including Lyme disease and babesiosis.

“The exotic diseases are not here, but can it make use of the existing ones?” Dapsis asked.

The longhorned tick has been known to carry pathogens that cause severe illness in people, but none of these have been detected in the ticks that have made it to the U.S., said Richard S. Ostfeld, senior scientist with the Cary Institute of Ecosystems Studies in Millbrook, New York.

“Officials are interested in whether it can acquire and then transmit the pathogens carried by the blacklegged tick,” Ostfeld wrote in an email.

“This could happen if it bites, say, a white-footed mouse that’s infected with Lyme bacteria. It is not known whether this is possible. But the longhorned tick does bite a lot of different species of wildlife and livestock, so it’s not impossible,” Ostfeld wrote.

Sam R. Telford III, a professor of vector-borne infection and public health at the Cummings School of Veterinary Medicine at Tufts University, said he does not think the longhorned tick is a threat to New England.

The tick made its way to Australia and New Zealand about a century ago, “and there has been no public health issue,” Telford said via email.

“They did not bring the Asian infections with them,” Telford said.

But with female ticks capable of laying larvae without help from males, “They could indeed spread like crazy,” Telford said.

And “with all the deer in eastern Massachusetts” serving as potential hosts and meals, “it could be very quick,” he said.

So far the longhorned tick has been reported in Arkansas, Maryland, New Jersey, New York, North Carolina, Pennsylvania, Virginia and West Virginia, according to published reports.

“It is thriving in northern New Jersey and southeastern New York, which are not too different ecologically from southern New England,” Ostfeld said.

“Their native range includes warm, temperate places without extreme winter cold, so perhaps they’ll be limited by cold temperatures to the north and west,” Ostfeld said.

If the longhorned tick does spread to Cape Cod, Dapsis said, people should take the same steps they use to avoid bites from blacklegged ticks: Wear permethrin-treated clothing and when walking in woods or grass wear light-colored clothing and tuck pants into socks.

Leave a Reply

%d bloggers like this: