Cycle of Rabies Infection

Rabies is a virus in the rhabdoviridae family that causes inflammation of the brain, behavioral changes, pain and death. There is no cure for rabies, but a vaccine is available for humans who are more likely to be exposed to rabies, such as game wardens, along with a vaccine for companion animals to reduce cases.

Life Cycle

• The rabies virus enters the host through a wound and moves along nerve fibers to the spine and brain. In the brain, the virus replicates, causing neurological damage and erratic behavior. From the brain, the virus spreads throughout the body, particularly the saliva, which is an efficient medium for infecting a new host.

Transmission

• Cases of rabies in humans are usually caused by contact with an infected animal. If the saliva from someone or something infected touches the mucous membranes of a new host, there is the potential for infection.

Signs and Symptoms

• Signs and symptoms of rabies infection include paralysis, aggression, convulsions, choking or the inability to swallow, depression and drooling.

Stages

• The five stages of rabies infection are incubation, prodrome, acute neurologic period, coma and death. Incubation can be from five days to two years. The prodromal phase is when symptoms first appear, followed by the neurologic period, when convulsions, paralysis and behavioral changes start. At some point, the victim lapses into a coma and eventually dies.

Recovery

• Most victims of rabies will die, but there are a few documented cases of humans recovering from rabies infection. Supportive care should be standard with all patients exposed to rabies, in some case they can recover if treated before symptoms appear