How Does Rabies Affect the Nerves?

Transmission

The rabies virus is spread through an infected animal's saliva and travels along the nerves after the bite. The nervous system plays a significant role in how the virus then travels throughout the body--from the site of infection, to the brain and into the saliva glands. The saliva can enter the body in two ways: either directly into the peripheral nerves, or into non-nervous tissues such as muscles cells. The peripheral nerves play a tremendous role in the virus's progression. Before the virus reaches the brain, it goes into an incubation phase in which the victim will experience no symptoms or ill effects.

Transportation

It is through the peripheral nerves that the virus travels to the central nervous system through a retrograde axoplasmic flow. From there, the virus travels rapidly to the limbic system neurons, salivary glands and into the saliva. At this point, the body's nerve systems are severely affected, beginning with the sensory and motor nerves at the site of the infection, and the victim will begin experiencing the worst of the disease's symptoms.

Affect on Nerves

The actual effects the virus has on the nerves are numerous. First, the sensory nerve endings in the head, face, neck and fingers tend to lead to a higher fatality rate when they are exposed to the virus. When the nerves of the infected salivary glands are affected, they cause painful throat and voice box spasms, making it difficult for the victim to swallow. The disease also produces too much saliva, causing the foaming-at-the-mouth effect associated with rabies. When the central nervous system or brain is affected, the symptoms for the disease worsen. This includes uncontrollable excitement, loss of muscle control and bodily functions, muscles spasms and paralysis.

References

• Natural History of Rabies
• Rabies