rabies

rabies or hydrophobia, acute viral infection of the central nervous system in dogs, foxes, raccoons, skunks, bats, and other animals, and in humans. The virus is transmitted from an animal to a person, or from one animal to another, via infected saliva, most often by biting but also by the contact of torn skin with infected saliva. The virus travels from the bite or contact location to the spinal cord and brain. In humans the incubation period ranges from 10 days to a year or more. Symptoms are fever, uncontrollable excitement, and pronounced spasms of the throat muscles. Salivation is extreme, and despite great thirst the victim cannot swallow water; hence the misnomer hydrophobia (fear of water). Once symptoms develop, death (caused by convulsions, exhaustion, or paralysis) is usually inevitable.

Following a bite from a rabid or possibly rabid animal, preventive treatment involves administration of immune globulin for passive immunization followed by vaccinations over several weeks for active immunization. The only treatment after symptoms appear is rest and sedation. Dogs have been immunized from the time Louis Pasteur demonstrated a successful vaccine in 1885. Since then, human rabies has become rare in the United States and other industrialized countries due to comprehensive vaccination programs for domestic animals. Mass vaccination of susceptible animals in the wild with vaccine-laced bait has been used in an effort to stem an increase of rabies cases in the United States and Canada that began in the late 1980s. A similar wild animal vaccination program has been used with some success in parts of Europe.

Acute, usually fatal infectious disease of warm-blooded animals that attacks the central nervous system. It is spread by contact with an infected animal's saliva, usually from a bite. The rhabdovirus that causes it spreads along nerve tissue from the wound to the brain. Symptoms usually appear four to six weeks later, often beginning with irritability and aggressiveness. Wild animals lose their fear of humans and are easily provoked to bite, as are pets. Depression and paralysis soon follow. Death usually comes three to five days after symptoms begin. In humans, death can result from a seizure in the early phase even before symptoms of central nervous system depression develop. One name for rabies, hydrophobia (“fear of water”), comes from painful throat contraction on trying to swallow. If not treated in time (within a day or two) with a serum containing antibodies and then a series of vaccinations, rabies in humans is almost always fatal. Immediate cleansing of animal bites with soap and water can remove much of the virus.

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