Rabies is a dangerous viral disease that many outdoorsmen and women have encountered in one form or another. Without treatment, the infection is almost 100 percent fatal. But a teenage girl who was bitten by a rabid bat eight years ago and survived without treatment had scientists racking their brains for an explanation.
A post-exposure vaccine is very effective at preventing the onslaught of neurological degradation from the virus, but not all persons infected by the disease are lucky enough to get a quick treatment. At least 55,000 people a year die of rabies worldwide, according to the World Health Organization. The United States is particularly free of rabies incidents, with only one or two occurring each year.
Dogs are responsible for the transmission of rabies in 99 percent of human cases resulting in death, especially in Asia and Africa. In North America, bats are the greatest source of human rabies deaths. A recent study on the virus observed humans who were infected by bats in the Amazon, namely Peru.
The study, published in the American Journal of Tropical Medicine and Hygiene, challenged conventional wisdom by saying that certain humans were able to naturally fight off the disease without the need for a vaccine.
“The overwhelming majority of rabies exposures that proceed to infections are fatal. However, our results open the door to the idea that there may be some type of natural resistance or enhanced immune response in certain communities regularly exposed to the disease. This means there may be ways to develop effective treatments that can save lives in areas where rabies remains a persistent cause of death,” said Amy Gilbert with the CDC’s National Center for Emerging and Zoonotic Infectious Diseases, and the paper’s lead author, on MedicalDaily.com.
Through their research, scientists found that 11 percent of people in the study group were naturally resistant to infections. By analyzing genetic factors of the study group, researchers hope to find new ways to treat the disease in the general population.
This is one of the first and strongest studies to show that humans can naturally develop rabies antibodies, according to the researchers. However, the reason why these people have developed an immunity is still unknown.