An invasive new tick is spreading in the U.S.

A new tick species has appeared in the United States, one that carries dangerous pathogens in its home range in Asia. So far, the Asian long-horned tick has been found in seven states and in New York City suburbs.

A new tick species has appeared in the United States, one that carries dangerous pathogens in its home range in Asia. So far, the Asian long-horned tick has been found in seven states and in New York City suburbs. No long-horned ticks have yet been found with any human diseases in the United States, and public health officials say they are concerned but not alarmed. In Asia, the species carries a virus that has an overall fatality rate of 15%. Researchers are still studying the ticks and will attempt to determine whether they can transmit Rocky Mountain spotted fever and other diseases. The new ticks are for now considered a bigger threat to livestock, as they can multiply quickly and be fatal for young animals. David Thompson, a veterinarian in Queensland, Australia, says that the ticks—known as bush ticks in Australia and cattle ticks in New Zealand—cause disease in cattle in those countries but are mostly "of nuisance value" to humans.