Two elderly men, one in Montana and the other in Washington state, died from rabies earlier this year after encounters with bats. The deaths have prompted federal health officials to recommend that people be treated for rabies if they have touched bats, whether or not they have been bitten.
In both cases, said officials at the Centers for Disease Control and Prevention, there is no evidence that the men were bitten by bats. The deaths were at first incorrectly attributed to a degenerative brain disease. And it was only in autopsies that the authorities discovered evidence of a strain of rabies common to bats.
“People will handle bats and not think anything about it,” said Dr. Lisa Rotz, a centers epidemiologist who reported on the deaths in Friday’s issue of the Morbidity and Mortality Weekly Report. “But contact with a bat should be taken seriously. Bats should not be handled or kept as pets. They are cute and all, but there is a real risk.”
People who have even limited, seemingly insignificant, exposure to bats should consult their doctors, Dr. Rotz said. Such exposure could include shooing a bat out of the house with a broom, as did the 66-year-old Montana man who died, or discovering one hovering over the bed in the middle of the night.
“Just walking into a room and seeing a bat obviously does not constitute something that would transmit rabies to you,” Dr. Rotz said. “But if you wake up to find a bat in the room and you can’t say for certain whether the bat has landed on you or bit you or scratched you during the night, then you should consider speaking with your doctor and possibly receiving treatment to prevent rabies.”
Rabies, a viral infection that travels through the nervous system and ultimately inflames the brain, is always fatal if not treated. It is very rare in the United States; only 34 cases have been reported since 1980, 19 of them attributed to bats.
But this year’s deaths, both in January, come at a time when centers officials have noticed a slight but significant rise in the annual incidence of the disease. From 1981 to 1993, the number of rabies cases ranged from zero to three, said Dr. Charles Rupprecht, chief of the rabies section at the centers. There were six cases in 1994 and four each in 1995 and 1996. But experts said it was also possible that additional rabies deaths might have been wrongly ascribed to other diseases.
Despite an epidemic of rabies among raccoons on the East Coast, Rupprecht said, there have been no reports of humans’ becoming infected by raccoons. Most of the new cases involve bats.
“It’s a very mysterious trend,” he said. “We are concerned; the majority of the cases of late have been bat-related, and we are struggling with why that is.”
One possible explanation, Rupprecht said, is a rise in reporting. Another is that victims of bat bites do not seek medical help; most bats are not rabid and many people do not realize that the bites can be dangerous. A third is that people do not realize that they have been bitten, as was the case with a child in Washington who died several years ago.
“Bats have small bodies and small teeth to very efficiently eat bugs,” Rupprecht said. “If I were to show you the jaw of the bat that bit the child in Washington, it’s only a few millimeters long.”
Treatment for people exposed to rabies is not nearly as painful as it was years ago, when patients received a series of excruciating shots in the stomach, said Dr. Claire Panosian, an infectious-disease specialist at the University of California at Los Angeles. The new therapy, called post-exposure prophylaxis because it is meant to prevent the disease after exposure, is two pronged.
First, patients receive shots of a rabies immune globulin, a horse serum with antibodies to the rabies virus, in both the arm and the area of the bite. Then they receive five separate shots of the vaccine.
Bite victims should be treated as soon as possible, and no later than 24 to 48 hours after the injury occurs, Dr. Panosian said. By the time the first, flu-like symptoms of rabies appear, she said, it is too late. And because rabies is so rare in this country, many doctors do not even recognize it when they see it.
That was the case for the Montana man, who was 66, and the Washington man, who has 64. Both times, doctors suspected Creutzfelt-Jakob disease, a neurological disorder that resembles mad cow disease.
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