Rabies is a viral disease that causes acute encephalitis in warm-blooded animals. For a human, rabies is almost invariably fatal if postexposure prophylaxis is not administered prior to the onset of severe symptoms. The rabies virus travels to the brain by following the peripheral nerves. The incubation period of the disease is usually a few months in humans, depending on the distance the virus must travel to reach the central nervous system. Once the rabies virus reaches the central nervous system and symptoms begin to show, the infection is virtually untreatable and usually fatal within days. Early-stage symptoms of rabies are malaise, headache and fever, progressing to acute pain, violent movements, uncontrolled excitement, depression, and hydrophobia. Finally, the patient may experience periods of mania and lethargy, eventually leading to coma. 95% of human deaths due to rabies occur in Asia and Africa. Roughly 97% of human rabies cases result from dog bites. In the United States, animal control and vaccination programs have effectively eliminated domestic dogs as reservoirs of rabies. In several countries, including Australia, Japan, and Singapore, rabies carried by terrestrial animals has been eliminated entirely. While classical rabies has been eradicated in the United Kingdom, bats infected with a related virus have been found in the country on rare occasions. deadly fatal sick sickness dog dogs cat cats mice mouse rat rats diseased ill illness illnesses dead alive health healthy weird crazy insane mad madness hat anger angry hate hateful attack attacking violent violence rabid rabies wild animal animals mammal mammals race track prevent prevention preventing air mouth saliva drool foam autopsy autopsies restore restoration restoring well wellness ability able sit stand lay sleep lie foaming symptom symptoms attacked bite biting bites carry carries carried push Soon after, the symptoms may expand to slight or partial paralysis, anxiety, insomnia, confusion, agitation, abnormal behavior, paranoia, terror, and hallucinations, progressing to delirium. Hydrophobia (fear of water), the historic name for the disease, refers to the dread of swallowing fluids these patients exhibit.[clarification needed] Death almost invariably results 2 to 10 days after first symptoms. Once symptoms have presented, survival is rare, even with the administration of proper and intensive care. cctv In 2005, Jeanna Giese, the first patient treated with the Milwaukee protocol, became the first person ever recorded to have survived rabies without receiving successful post-exposure prophylaxis. An intention-to-treat analysis has since found this protocol has a survival rate of about 8%. The virus has even been adapted to grow in cells of poikilothermic ("cold-blooded") vertebrates. Most animals can be infected by the virus and can transmit the disease to humans. Infected bats, monkeys, raccoons, foxes, skunks, cattle, wolves, coyotes, dogs, mongooses (normally yellow mongoose) or cats present the greatest risk to humans. Rabies may also spread through exposure to infected domestic farm animals, groundhogs, weasels, bears, raccoons, skunks and other wild carnivorans. Small rodents, such as squirrels, hamsters, guinea pigs, gerbils, chipmunks, rats, and mice, and lagomorphs such as rabbits and hares, are almost never found to be infected with rabies and are not known to transmit rabies to humans. The Virginia opossum is resistant but not immune to rabies. The virus is usually present in the nerves and saliva of a symptomatic rabid animal. The route of infection is usually, but not always, by a bite. In many cases, the infected animal is exceptionally aggressive, may attack without provocation, and exhibits otherwise uncharacteristic behavior. This is an example of a viral pathogen modifying the behavior of its host to facilitate its transmission to other hosts. Transmission between humans is extremely rare. A few cases have been recorded through transplant surgery. After a typical human infection by bite, the virus enters the peripheral nervous system. It then travels along the afferent nerves toward the central nervous system. During this phase, the virus cannot be easily detected within the host, and vaccination may still confer cell-mediated immunity to prevent symptomatic rabies. When the virus reaches the brain, it rapidly causes encephalitis, the prodromal phase, and is the beginning of the symptoms. Once the patient becomes symptomatic, treatment is almost never effective and mortality is over 99%. The human diploid cell rabies vaccine was started in 1967; a new and less expensive purified chicken embryo cell vaccine and purified vero cell rabies vaccine are now available. A recombinant vaccine called V-RG has been successfully used in Belgium, France, Germany, and the United States to prevent outbreaks

• published: 25 Dec 2013
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