The herpes simplex viruses, HSV-I and HSV-II, penetrate the body through breaks in the skin and then enter nerve cells. Once in the nerve cell, they are transported along its axon to the nucleus, where they will reside all life long. After the initial infection, symptoms recur whenever the virus migrates along the neuron to its ending. Symptoms such as blisters are neurological, not dermatological, since they are caused by accumulation of the virus in the nerve ending.
Cold Sores
Cold sores are a common manifestation of herpes. They usually appear on the lips near the angle of the mouth. The sore is a painful, fluid filled, blister that lasts about a week or two, till it crusts over and heals. Cold sores are precipitated by emotional stress, fever and sun exposure.
Genital Herpes
Symptoms include tingling, pain, blisters and ulcers in the genital area. Pain and itching usually precede the appearance of the blisters. Herpes can be infectious even when not symptomatic. Like facial herpes, the virus remains in the nerve cells for life and will be reactivated once in a while. According to the Illinois Department of Public Health, some people have recurrences a few times a year, others only a few times in their lives.
Blindness
According to "Harrison's Principles of Internal Medicine," herpes infection is a common cause of blindness. The virus can affect the cornea and cause keratitis. Symptoms include pain, blurred vision and sensitivity to light. The infection gets worse the more times it recurs, and can lead to ulcers, scars and eventually blindness.
Encephalitis
Herpes encephalitis is a devastating brain infection. Symptoms include fever, headaches and personality changes. According to "Adams and Victor's Principles of Neurology," the virus affects the temporal lobe preferentially, leading to symptoms such as strange behavior, partial complex seizures, hallucinations and memory disturbances. Even with treatment, long term neurological complications are common. One possible complication is Korsakoff's amnesia, a severe impairment of memory in which the patient loses the ability to learn and retain new material. The patient's nearest and dearest become strangers to him, and they have to reintroduce themselves every time they meet. Korsakoff's is a permanent and extremely disabling condition.
References
- "Harrison's Principles of Internal Medicine, 17th edition"; Anthony Fauci et al.; 2008
- Illinois Departement of Public Health: Herpes
- "Adams and Victor's Principles of Neurology"; Maurice Victor and Allan Ropper; 2001
