However, a 2002 study has supported the protocol of precautionary administration of PEP where a child or mentally compromised individual has been alone with a bat, especially in sleep areas, where a bite or exposure may occur with the victim being unaware. After onset
At least two treatment schemes have been proposed for treating rabies after the onset of symptoms, the Milwaukee Protocol and the Recife Protocol. The Milwaukee Protocol was first used in 2004 on Jeanna Giese, who became the first person known to have survived rabies without preventive treatments before symptom onset. The protocol puts a person into a chemically induced coma and uses antiviral medications to prevent fatal dysautonomia. The overall protocol is complex; the sixth version of the protocol last updated in 2018 consists of 17 pages with 22 steps of treatment, detailed monitoring, and a timeline of expected complications. The Recife Protocol follows the same principle but differs in details like termination of sedation and supplementary medication. Prognosis
Vaccination after exposure, PEP, is highly successful in preventing rabies. In unvaccinated humans, rabies is virtually always fatal after neurological symptoms have developed. Epidemiology
In 2010, an estimated 26,000 people died from rabies, down from 54,000 in 1990. The majority of the deaths occurred in Asia and Africa. As of 2015, India, followed by China (approximately 6,000) and the Democratic Republic of the Congo (5,600), had the most cases.
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. After a typical human infection by bite, the virus enters the peripheral nervous system. It then travels retrograde along the efferent 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, which is the beginning of the symptoms. Once the patient becomes symptomatic, treatment is almost never effective and mortality is over 99%. Rabies may also inflame the spinal cord, producing transverse myelitis.Although it is theoretically possible for rabies-infected humans to transmit it to others by biting or otherwise, no such cases have ever been documented, because infected humans are usually hospitalized and necessary precautions taken. Casual contact, such as touching a person with rabies or contact with non-infectious fluid or tissue (urine, blood, feces), does not constitute an exposure and does not require post-exposure prophylaxis. But as the virus is present in sperm and vaginal secretions, it might be possible for rabies to spread through sex. There are only a handful of recorded cases of human-to-human transmission of rabies, and all occurred through organ transplants from infected donors.