By Alex DeMetrick

BALTIMORE (WJZ) — It has killed millions of bats and threatens to kill many more.  A lethal fungus, unheard of in the U.S. just a few years ago, continues to spread.

Alex DeMetrick reports Maryland is now right in the middle of it.

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Bats that once thrived in American caves suddenly started dying during hibernation in large numbers in 2006.

By 2010…

“Areas where it was first discovered, they’re finding complete devastation of the hibernacula.  No bats are there,” said Dana Limpert, DNR Natural Heritage Program.

The killer is called white-nose syndrome, for the fungus that forms around a bat’s nose.  For unknown reasons, bats stop hibernating and start flying in winter.  Without insects, they starve to death.

Seen first in New York, the syndrome has spread north and south. Bats are now dying in 16 states, including Maryland.

“We’ve discovered white-nose syndrome in a number of our important bat caves in Western Maryland,” said Jonathan McKnight, DNR Wildlife & Heritage. 

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Bu those caves are small, compared to Indigo Tunnel.  It is Maryland’s largest spot for hibernating bats and is closely monitored by biologists.

During a survey in 2010, no dead bats were found. And there is still no sign of the fungus today.

“And we’re extremely hopeful we can keep it that way,” said McKnight.

Researchers believe the fungus somehow got here from Europe, where bats are resistant to it.  U.S. Fish and Wildlife estimates as many as seven million bats have died, and there’s no known way to stop it.

And as bats vanish, insects that eat crops and spread disease will increase.

“Little brown bats eat about 1,000 mosquitoes an hour,” said a researcher.

If there’s no cure, there’s hope the bats will somehow develop resistance to the fungus if enough survive.

“I think it’s too early to talk about an extinction event, but it is a catastrophic event,” said McKnight.

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In agriculture alone, it’s estimated bats save U.S. farmers $1 billion a year in insect control.