The varicella-zoster virus is the cause of Ramsay Hunt syndrome II. It can lie dormant in the body for decades after its first incarnation as chickenpox. A recurrance of the virus is shingles and one complication of shingles is Ramsay Hunt syndrome.

The varicella-zoster virus infection may lead to inflammation or damage to the seventh cranial nerve (facial nerve carrying about 7,000 'fibres' which control the facial muscles) over a number of days. Responses to the inflammation can include any or all of the following: the onset of paralysis of one side of the subject's face, ear or facial pain on one side, loss of the sense of taste on one side of the tongue, dizziness, and one-sided hearing loss or tinnitis. Although initial symptoms seem to be quite dramatic many patients may experience a full and complete recovery. The chances of a good recovery are currently thought to be about 70%.

The Varicella Zoster Virus

People who have had chickenpox (varicella zoster) in their youth can develop shingles (herpes zoster) in later years. During an acute attack of the chickenpox virus, most of the viral organisms are destroyed, but some survive, travel up nerve fibers along the spine, and lodge in nerve cells where they may lie dormant for many years. A decrease in the body's resistance can cause the virus to reawaken decades later. It then travels back down the nerve fibers to the skin's surface.

The reawakened virus generally causes a vague burning sensation or tingling over an area of skin. A painful rash usually occurs two to five days after the first symptoms appear. A cluster of small bumps (1) turns into blisters (2) that resemble chickenpox lesions. The blisters fill with pus, break open (3), crust over (4), and finally disappear. This process takes four to five weeks.

A painful condition called post-herpetic neuralgia can sometimes occur. This condition is thought to be caused by damage to the nerves (5), and can last from weeks to years after the rash disappears.