How to: Survive rabies without really trying

This is an awkward sort of "How To" post because nobody really knows the answer. Here's the rather bleak reality: Rabies is not, typically, something you live through. If you think you've been exposed, you can get a life-saving vaccine. But, if you miss that window, and symptoms start to appear, your chances of survival are pretty much nil.

There are exceptions. We've talked before here about the Milwaukee Protocol, a medical intervention that some doctors think has allowed a handful of people to escape death. But the Milwaukee Protocol is not a simple thing. It involves hospitalization, as doctors put the affected person into a coma. Basically, they reboot the system. And it might not be as effective as we think it is. Five people have gotten the Milwaukee Protocol and survived. Thirty-two others received the treatment and still died. There's a lot of effort that goes into the Milwaukee Protocol, and it might be wasted effort.

Then there's this: In 2009, a teenage runaway walked into a Texas hospital, exhibiting symptoms of rabies—a diagnosis that was later confirmed. She didn't get vaccinated before symptoms started. She never got the Milwaukee Protocol. Instead, she recovered on her own and left the hospital hale and healthy three weeks later.

That's not supposed to happen in humans.

The Austin American-Statesman has a fascinating story about this case. At the heart is a big mystery. The young woman cut off contact with hospital researchers shortly after she was discharged from the hospital. She was homeless—in fact, she'd probably contracted rabies from a bat while camping in a cave. There's a very good chance that we may never know why she survived when so many others don't.

Veterinarians know that not all animals die after exposure — usually from a bite — to the rabies virus, which is carried in saliva and other bodily fluids. Much depends on how much of the virus is transmitted, the severity and location of the bite, and the immune system of the bitten animal.

"Abortive rabies is not unusual in research animals — it happens spontaneously all the time," Rupprecht said.

Rupprecht said the blood of certain human populations — maybe 1 percent of raccoon hunters, for example — also tests positive for rabies antibodies, indicating they have been exposed to the virus without becoming acutely ill. In the Amazon, where indigenous tribes are at daily risk of rabies from vampire bats, "it could be in the 10 percent or more range," he said.

The rabies vaccine, injected in a series of five doses, prevents onset of the disease if given soon enough after exposure. About 35,000 people receive the expensive shots — the series costs about $1,600 — in the U.S. each year. Seldom do more than a handful of people die from rabies in a year. But once rabies symptoms appear, the vaccine is no help.

"We don't have poster children. In our field, 99.9 percent of our cases are in the ground," Rupprecht said.

Read the rest of the article at the Austin American-Statesman

Image: White-Shouldered Bat, a Creative Commons Attribution Share-Alike (2.0) image from wilsonb's photostream

Via GrrlScientist