Rabies
Section snippets
Transmission
This zoonotic disease, found in unvaccinated domestic and wild animals, is typically transmitted to humans via bites and scratches containing saliva infected with the rabies virus. The virus travels along the peripheral nerves to the brain, where replication takes place. The replicated virus then spreads to tissues via the nervous system, with a large concentration of the virus found in the salivary glands. The incubation period for the virus is typically 1 to 3 months; however, the incubation
Clinical Presentation
Initial symptoms for those infected with rabies are often non-specific and may include fever, headache, weakness, and/or pain at the wound or bite site. These non-specific symptoms often make it difficult to diagnose the illness, as rabies may not be suspected, especially in cases where an unknown bite or scratch has occurred.
There are two clinical presentations in humans with rabies: furious or encephalitic rabies and paralytic rabies. Symptoms with both clinical presentations of rabies are a
Diagnosis
The “gold standard” for the diagnosis of rabies is the direct fluorescent antibody (DFA) test. Used for over 50 years, this method is the only recommended diagnostic test method for testing animal specimens in the U.S. (9). In the DFA test, a fluorescently labeled anti-rabies antibody binds to rabies antigen found in the nervous tissue of the brain. Rabies antigen stains fluorescent apple green and has a “starry-night appearance,” as seen in Fig. 1. In animals suspected of having rabies,
Prevention
The first rabies vaccine was produced by Louis Pasteur in 1895. Having pets vaccinated against the rabies virus is the best way to avoid human exposure to rabies. Indeed, the decline in human rabies in the U.S. has been attributed to rabies prevention programs in which domestic animals are vaccinated for protection against the rabies virus. Rabies is a preventable disease for animals that receive the vaccine.
It is also important to teach and remind children not to approach stray animals,
Prevention and Control
The rabies virus, though rare in the U.S., has a global mortality impact. Worldwide, over 55,000 people die from rabies each year, and over 15 million people receive post-exposure prophylaxis for potential rabies exposure. Depending on the circumstances of the bite or scratch, post-exposure immunizations may be started immediately after seeking medical care or may be delayed for 10 days while an animal is confined for observation.
One should always be aware of areas with high risk of rabies when
References (12)
Rabies surveillance in the U.S. during 2009
J. Am. Vet. Med. Assoc.
(2010)Effects of aerosolized rabies virus exposure on bats and mice
J. Infect. Dis.
(2007)