Worried about a Cascadia subduction-zone earthquake? Worried about nuclear war? Worried about climate change?

Phhffft!

Those potential calamities are nothing. If you want to really have nightmares, read on to find out what’s happening to cows in North Carolina -- and what it could mean for humans.

Asian longhorned ticks, also sometimes called “clone ticks” because they can reproduce without mating, have killed five cows in the Tar Heel State this year -- by draining them of blood. Each cow was infested by hundreds of ticks.

“The official cause of death,” writes technology news site Ars Technica, “was acute anemia, which is typically associated with severe hemorrhaging.”

These ticks are extremely aggressive; New Jersey health investigators in 2017 reported them swiftly clambering up their legs while they investigated a tick assault on a sheep paddock. The ticks’ usual killing grounds are in Russia and Asia, where they are known to spread various serious diseases to humans. It’s not known how or exactly when they arrived in the U.S. So far the ones found in North America have not carried disease.

What appears to be an Asian longhorned tick found in New York in 2018. (Staten Island Advance)

“The first case identified in the U.S. was in West Virginia from a tick taken from a white-tail deer in August 2010,” the North Carolina Department of Agriculture & Consumer Services wrote in a July 8 warning to livestock owners. “Since then, 67 counties in the United States have confirmed local Asian longhorned tick populations. Virginia has the most counties with 24 confirmed.”

The state agency added: “The tick can reproduce parthenogenetically (without a male) and a single fed female tick can create a localized population.”

The Centers for Disease Control and Prevention points out that “Asian longhorned ticks have been found on pets, livestock, wildlife and people.”

In May came the first known case of an Asian longhorned tick biting a human in the U.S. This happened in New York state. “Subsequent field studies confirmed that this tick was present in multiple geographic locations near the patient’s residence, including on manicured lawns,” wrote the journal Clinical Infectious Diseases.

In the U.S., Asian longhorned ticks have been found in Arkansas, Connecticut, Kentucky, Maryland, New Jersey, New York, North Carolina, Pennsylvania, Virginia, Tennessee and West Virginia.

The CDC recommends that people take precautions against ticks, such as avoiding “wooded and brushy areas with high grass and leaf litter,” and to examine clothing and do a “full-body check” after being outdoors.

-- Douglas Perry

@douglasmperry

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