A study published on August 1 in the American Journal of Tropical Medicine and Hygiene reported that rabies may not be fatal in all patients who do not receive treatment. Among the study population in the Peruvian Amazon, ten percent of participants reported surviving exposure to rabies, and another eleven percent were confirmed to have antibodies in their blood that neutralize the disease.
Researchers interviewed 92 individuals from an area with a large bat population. While most bats do not actually have rabies, they are the source of most human deaths of rabies in the Americas and in western Europe. Dogs are the most common transmitters of rabies in Africa and Asia, but because most domestic animals in the United States are vaccinated, wild animals, such as bats, become the predominant source of transmission. Because of the large bat population in this region of Peru, exposure to the disease is widespread. However, little research has been done on rabies resistance in areas where the disease is endemic due to high carrier populations.
Most reported cases of rabies in the United States occur in wild animals, such as raccoons and skunks, with only two to four deaths reported annually. However, the disease kills more than 55,000 worldwide each year. Rabies incidence is on the rise in China, the former Soviet republics, and Central and South America.
This research has implications for further research in infectious diseases that currently have no cure. Dr. Rodney Willoughby Jr., a pediatric infectious disease specialist at Children’s Hospital of Wisconsin wrote in an editorial accompanying the research, “Knowing that there is a continuum of disease, even for infectious diseases like rabies, should push us harder to try for cures when confronted by so-called untreatable infectious diseases.”
Rabies is transmitted by the bite of an infected animal and is not contagious between people. It affects the central nervous system and usually kills within a few days of the onset of symptoms. Post-exposure injections are generally 100 percent effective in treating the disease if administered promptly.
Pets are also at risk of rabies infection when they are bitten or scratched by an infected wild animal. Symptoms of the disease include behavior changes such as irritability, followed by paralysis and foaming at the mouth. If you believe your pet may have been infected, experts recommend calling your veterinarian and avoiding touching the animal.
For more information on rabies, please consult HealthMap’s piece on World Rabies Day, which occurs on September 28.