SEATTLE, WA — Two bats in King and Pierce counties recently tested positive for the deadly "white-nose syndrome" infection, which has killed millions of bats in the U.S. since it emerged along the East Coast in more than a decade ago.

The white-nose syndrome case found in King County was in a western long-eared bat — the first ever found in North America with the infection, and now 12th species of bat affected by white-nose syndrome. The Pierce County case was in a brown bat. Both animals were found dead. White-nose syndrome is caused by the fungus Pseudogymnoascus destructans, which infects bat skin and wing tissue, leading to dehydration, starvation, and death. The fungus is not harmful to humans, but humans can spread the spores during outdoor activity.

A total of 30 cases of white-nose syndrome have been found in Washington since 2016, and 29 of those were in King County. Local bats are an important part of the ecosystem. They eat pesky bugs like mosquitoes, and bugs that damage crops and forests. "Confirming another species with white-nose syndrome is concerning, but something we've anticipated," state department of Fish and Wildlife white-nose syndrome coordinator Abby Tobin said in a recent statement. "We are grateful for the public's involvement in reporting sick or dead bats, as it helps us monitor bat populations and track the spread of this catastrophic disease in Washington."