ALAMEDA, Calif. (KTVU) - Alameda County workers handed out rabies alerts Thursday in the Sunol neighborhood where the latest rabid bat was found.
The health department says a resident found the bat at her home Saturday and took it to a CalFire station, where staff passed it on to county officials for testing. The results came back positive.
"We have four rabid bats already and last year we only had two rabid bats for the whole year," said Daniel Wilson, an Alameda County Vector Control spokesman.
All of the rabid bats tested were Mexican free-tailed bats.
"They are actually one of the more common species here in the Bay Area and these guys are interesting because they live in large colonies," said Sarah Parnell, a program manager at the Lindsay Wildlife Museum in Walnut Creek.
Parnell showed KTVU one of the three Mexican free-tailed bats that are part of the museum's collection.
The bats aren't big or bloodthirsty. Rather, they are about the size of a mouse, have a little tail, and they feast on insects.
County health officials say they don't know why there are so many cases so early in the year. Historic data going back to 1995 shows the number of annual cases in Alameda County has fluctuated between 1 and 9 rabid bats.
"They're common, you have old barns and stuff in Sunol and there are going to be bats and all that sure," said Tom Stillman, a longtime Sunol resident, "There's a lot of animals out here so I'm not surprised."
The previous 2015 cases include two bats found in Fremont. One was found by a man walking his dog. That dog is on quarantine after picking up a rabid bat behind Niles Elementary School on March 13th.
Another rabid bat was found in Fremont near the Irvington Community Center. The first rabid bat of the year was found in San Leandro in February.
Rabies is a deadly virus if left untreated, so Alameda County health officials say it's important people and their pets avoid contact with bats or other wild animals, which can transmit the virus through bites and saliva.
"The ones that are down on the ground, the ones that are out during the day acting abnormally, they're sick," said Parnell.
Wildlife experts estimate about one percent of the bat population has rabies.
They advise that people give their pets a preventative rabies vaccine.
Anyone who might have had any contact with a bat should get medical attention immediately.
Symptoms of rabies begin with flu-like symptoms but can progress to hallucinations, insomnia, and delirium.