Rabies is among the world's oldest known human pathogens, and each year it kills more than 60,000 people, according to the World Health Organization (WHO). But research now underway aims to limit the prevalence of rabies, improve vaccinations and learn more about the virus itself to find more effective treatments — and, ultimately, a cure.
Prevalence and control
Successful efforts in developed parts of the world, which are described in the October 2014 issue of The Lancet, indicate that vaccinating dogs is an effective and affordable way to control the disease. But efforts need to be extended beyond dogs to include other mammals. For example, researchers published a literature review in the April 2014 issue of PLOS Medicine demonstrating that the virus can exist among primates. The researchers note that in some parts of the world, primates are kept as pets or live in close proximity to humans, but their potential threat to public health is not well understood.
A 2010 WHO report suggests that without vaccination, an estimated 327,000 people — many of them children — would die of the disease. A number of research projects are underway, working to make vaccinations safer, more affordable and, thus, more accessible, particularly for people living in remote parts of the world where the disease is most prevalent. Researchers at the Monash School of Biomedical Sciences in Australia, for example, have developed a vaccine that can be developed in large quantities and be delivered in a single dose, rather than the multiple doses that are now required. Other research projects focus on improving purification methodologies, producing equine-originated serum and minimizing side effects and allergic reactions.
Rabies and humans
In humans, it has been found that the virus can incubate for years before symptoms develop. In the January 2014 Annals of Neurology, researchers described this phenomenon, which confirmed the death of a Brazilian man from rabies eight years after he was exposed to the virus. There also have been instances in which the disease has not proven lethal; a study published in the April 2012 issue of the American Journal of Tropical Medicine and Hygiene reported the discovery of nonfatal exposure from the bite of vampire bats among certain people living in the Amazon. Similarly, another article published in the same journal relies on case examples to challenge the notion of a 100 percent mortality rate among untreated humans.
At the David Geffen School of Medicine at UCLA, researchers recently reported possibly finding "a broad-spectrum antiviral that will fight a host of viruses." According to Dr. Otto Yang, professor of infectious diseases at UCLA, rabies research has plateaued to some degree. He especially hopes to see further advances in treatment for what he describes as a "horrible" disease. Rabies is far from being defeated — but the research gives hope that it will one day meet its match.