Rabies is an acute viral encephalomyelitis or inflammation of the brain and spinal cord of humans and other mammals, especially carnivores. The disease, known since antiquity, is almost always transmitted to human beings in the saliva of biting animals and is almost invariably fatal. The name hydrophobia, “fear of water, ” and the French term la rage illustrate two common symptoms.
Distribution and Incidence
Rabies occurs in most of the world, including Africa, Asia, the Americas, and most of Europe. It has never occurred in, or has been eliminated from, Britain, Ireland, Sweden, Norway, Japan, Australia, New Zealand, Hawaii, and many other islands in the Pacific and the Caribbean. Rabies is primarily a disease of wild carnivores, particularly canids such as the fox, wolf, jackal, and coyote. Skunks and raccoons are also common hosts, as are many species of bats. Virtually any species of mammal can contract the disease when bitten by an infected animal. Domestic dogs are the major threat to humans; cats are a growing danger in North America. Cattle, horses, sheep, and other livestock may also be affected. Outbreaks among farm animals may cause considerable economic loss, but bovine or equine rabies usually poses little danger for humans.
Rabies is a relatively uncommon disease in humans, occurring sporadically as isolated cases or in small clusters. Epizootics develop at irregular intervals in wild carnivores, and may infect humans mainly through dogs or rarely directly. Persons working alone in remote areas, such as hunters, trappers, or shepherds, are vulnerable to attack by infected animals.