Asian longhorned ticks are spreading across the U.S.

Researchers say the ticks arrived in 2017. They are warning people after three cows in Ohio died from tens of thousands of bites. Scientists were able to gather nearly 10,000 ticks in just an hour and a half at the cow pasture.

The Centers for Disease Control and Prevention says the ticks have also been found in Connecticut, New Jersey and New York.

Researchers say the tick can survive harsh conditions. It’s unclear whether they can pass diseases to humans.