Description

• A rapidly progressive CNS infection caused by a ribonucleic acid (RNA) rhabdovirus affecting mammals, including humans
• The disease is generally considered to be 100% fatal once symptoms develop.
• System(s) affected: Nervous
• Synonym(s): Hydrophobia (due to inability to swallow water)

Epidemiology

• Most cases are in developing countries.
• Estimated 55,000 deaths worldwide per year
• Only 1 death in the US in 2007
• Only 3 cases in the US in 2006
• Predominant age: Any
• Predominant sex: Male = Female

Risk Factors

• Professions or activities that may expose a person to wild or domestic animals (e.g., animal handlers, lab workers, veterinarians, spelunkers [cave explorers])
• In the US, most cases due to exposure to bats
• Internationally, many countries still have rabies widespread in both domestic and feral dogs.
• Human-to-human transmission has occurred through cornea and other tissue transplants.
• International travel to countries where canine rabies is endemic

General Prevention

• Pre-exposure vaccination if at risk of unapparent or unrecognized exposure to rabies, such as traveling to endemic areas
• Pre-exposure vaccination for high-risk groups such as veterinarians, animal handlers, and certain laboratory workers
• Consider pre-exposure vaccination for travelers visiting relatives in areas, such as North Africa, that have increased risk of rabies from domestic animals.
• Immunization of dogs and cats
• People who observe abnormal behavior in any wildlife species should contact animal control and should avoid approaching or handling those animals.
• Avoid wild and unknown domestic animals.
• Seek treatment promptly if bitten, scratched, or in contact with saliva.
• Infection can be prevented by prompt postexposure treatment of persons bitten by or otherwise exposed to animals known or suspected to be carrying the disease.
• Postexposure prophylaxis should be considered for any person who reports direct contact with bats, unless it is known that an exposure did not occur.

Pathophysiology

Lyssavirus, which is an RNA virus in the family Rhabdoviridae

Etiology

• Rabies virus, a neurotropic virus present in saliva of infected animals
• Transmission occurs via bites from infected animals or rarely via saliva coming in contact with open wound or mucous membranes.
• In the US, bats are the most common source of rabies.