Myelin sheath is generally formed by Schwann cells when it comes to peripheral nerves and oligodendrites in central nerves. Between two neurons, there is often a synapse (point of communication). Synapses often result between presynaptic axon neuron and a cell body of other neuron or dendrite. At presynaptic junction, there are often a lot of synaptic chemicals which often contain neurotransmitter chemicals. Between two neurons, a space exists called synaptic cleft (Alan & William 63).
Rabies is commonly transmitted via bites from a rabid animal. In rare cases, there have been cases of people getting rabies through contact with saliva that is infected with open wounds or mucous membrane (Alan & William 10). Other people have got it through transplants and through infected bat caves via aerosol route.
When one is bitten, the virus often gets bound to muscle or nerve cells through nicotinic acetylcholine receptors. It may replicate in incubation phase in the given muscle cells without resulting to any symptoms (Alan & William 11). This phase may last for several months.
By use of retrograde transport, the nerves can be able to enter nerve cells and gain entry to the central nervous system (Alan & William 13). May first reach dorsal root ganglia of spinal cord, and even move to the brain. In brain, may affect purkinje cells, cerebellum, pontine nuclei and even hippocampus in prodromal phase (Alan & William 16).
Once in brain, neurological phase can result when it result to encephalitis, coma and even spread to via neurons to eye, skin, salivary glands, kidneys, adrenals, pancreatic islets, and etcetera (Alan & William 23).
In general, infected cases often exhibit the following symptoms. Pain/itching at site bitten, headache, fever, gastrointestinal problems at prodromal/incubation period.