Thoracic and lumbar dermatomes are the most commonly involved, presumably because this is the area of greatest VZV infection in the primary infection. The onset of the disease is preceded by pain 48 to 72 hours before the rash develops in the affected dermatome. The rash appears as erythematous, maculopapular lesions that rapidly evolve into vesicles. The vesicles may coalesce and form bullous lesions. The lesions continue to form for 3 to 5 days, with a total duration of the disease of 10 to 15 days.
Herpes zoster can affect the cornea and be followed by iridocyclitis, secondary glaucoma.
This condition is known as herpes zoster ophthalmicus and is sight threatening. The pain can be very intense in adults and may be worse at night or with exposure to temperature changes. Fifty percent of persons older than 50 will suffer debilitating pain for more than 1 month. Frequently there are no clinical symptoms. After central nervous system zoster, granulomatous cerebral angitis can be found.