Asian longhorned ticks are spreading across Ohio, threatening livestock
They're tiny and brown, and they're crawling their way across Ohio.
The Asian longhorned tick (ALHT) is an exotic species first reported on U.S. soil in 2017 and has since been found in at least 17 states.
So far, they've been found in at least five Ohio counties, most recently in Morgan County.
“They're generally a bit smaller than some of the ticks that we are used to seeing. They're pretty bland. They're plain brown ticks. And they have really triangular mouthparts, which is pretty distinct," said Resa Pesane, an assistant professor in The Ohio State University College of Veterinary Medicine.
“I started here in 2019," Pesapane said, "And I looked at the map and I thought to myself, 'Well, there's just no way I buy that these Asian longhorned ticks are abiding by this geopolitical border along the Ohio River. I think they might be here in some number.'”
Since then, Pesapane has been one of the lead investigators tracking the ticks' spread in Ohio.
ALHTs can reproduce without a mate, in a process called parthenogenesis. Just one female can lay thousands of eggs.
It's a fact that's alarming to cattle farmers like Tricyn Huntsman-Parker, who is also a veterinarian with a practice in Brown County, Ohio.
“You're talking about them sucking the animal dry," Huntsman-Parker said. "So if you have a young calf, and it gets a swarm of these, they'll kill it.”
ALHTs are suspected in a handful of cattle deaths last year in southeastern Ohio.
Not only does this tick feed in extraordinary numbers, but it can also carry an aggressive and exotic pathogen called Theileria orientalis Ikeda. It's a protozoon for which cows in the U.S. have no natural defenses.
"It causes severe anemia, much like [bovine] anaplasmosis," Pesapane said. "This presents very, very similarly. So it can be hard to distinguish initially, but it does cause cattle losses in areas as well."
It's not just livestock at risk. Pesapane said ALHTs have been shown to feed on over 26 animal species in the U.S.
"This tick is tasting the buffet of all the available hosts and the U.S. as a new species exploring its space," she said.
As this tick branches out to varying hosts, there's concern that it might be able to transmit human pathogens as well.
"We need to understand that where we're at now is different than where we used to be," said Ohio State University Extension educator Timothy McDermott. "We didn't really have worries that we were going to have disease vector to us for a tick bite a while back, and now those worries are real."
McDermott, who spent two decades practicing veterinary medicine, said these ticks call for an "integrated pest management strategy" to protect Ohio's cattle farms.
“We do have products that are effective, but we need to also do things like scouting in the field management, intensive grazing, making sure that we bring all the tools in the toolbox to bear for something of this potential magnitude," he said.
Jason Workman is a seventh-generation cattle farmer and the owner of Twin Oak Farms in Ashland County, Ohio.
He said some of his friends in the cattle business are already dealing with ALHTs. He's bracing for when—not if—these ticks reach his farm.
“When a calf is born, it takes up to two years to see the first return on it. So if [ALHTs] kill a cow, and you're trying to replace it, you're already two years back," Workman said.
He said they already treat their animals for ticks and other parasites, but wonders how he'll keep ALHTs from infesting his fields. Still, he remains undaunted.
“Mother Nature's in control of everything. She's going to do what she wants, "Workman said. "It could be the climate, it could be the weeds, it could be anything... You just got to improvise and work through it," he said.
Anyone who comes across large infestations of ticks is urged to report them to their local county extension office or veterinarian.
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