Beware L.A. County’s rabid bat boom

Healthy bats, like the one shown above, fly by night and avoid humans. Watch out for daytime sightings.

They’ve shown up in homes in Malibu and Topanga, in a Burbank restroom, on a Van Nuys sidewalk and a closet in Hollywood. In a Santa Clarita barn. In a flower bed in Palmdale. In a cat’s mouth in Glendale.  In the front door entrance to a Pasadena building and a Northridge home where five people were sleeping. In a Los Angeles school.

A record 45 rabid bats have been captured so far this year in the county—four and a half times the normal average for the area. Health officials say that so far, the reasons are unclear; last year’s count also was much higher than normal. But for safety reasons, members of the public are being urged to steer clear of the critters—and all wild animals—and to make sure that pets have up-to-date vaccinations for rabies.

“It is important that everyone understand the potential dangers posed to themselves and their pets, as most of these rabid bats have been found in and around homes,” Director of Public Health Dr. Jonathan E. Fielding said in a statement.  “Children and teens especially should avoid handling bats or other wildlife, even if their intentions are to nurse an injured or ill animal back to health.”

Karen Ehnert, acting director of the county’s veterinary public health program, says she has been talking to local wildlife biologists, but so far hasn’t received any information on what might be causing the outbreak.  “Whether there are more bats in the area and therefore more crowding, or some sick bats migrated in and started spreading it, we don’t know,” she says.

But she knew early this year that the incidence of bat rabies was going to be a problem.

“Usually if I start seeing cases in April and May, there’s more transmission going on,” she says. “Well, this year, I saw the first case in January.”

Typically, Ehnert says, she sees about ten rabid bats in an entire year in L.A. County, and by April, she had already counted nine cases.  Moreover, she says, the percentage of captured bats testing positive for rabies has been rising.

“Usually only about 13% test positive,” says Ehnert. “But last year, it was up to 17% positive. And this year it was 20%.”

Only about 1% of bats are typically infected with rabies in nature, but they are the most common carriers in Los Angeles County, according to public health officials. Healthy bats eat insects, pollinate plants and typically fly only at night and avoid humans. However, the public health department warns that bats flying in daylight, or found on the ground or indoors near a sleeping person should be captured and tested for rabies.

Never pick up a bat with bare hands. Public Health recommends calling a local animal control agency (click here for a list of local animal control numbers), or, in urgent situations, putting on gloves and protective clothing and trapping the animal in a box or a bucket without touching it. Bats are protected by federal law and can only be removed via humane release; it is illegal to try to exterminate them.

If you are exposed to a bat, seek immediate medical attention; bats have very small, sharp teeth and their bites can be hard to detect. And don’t panic. Ehnert says that if you’re bitten, you can recover as long as you receive treatment before you start to develop symptoms. Los Angeles County hasn’t had a case of full-blown human rabies in more than 50 years.

Posted 9/12/12