They may rupture or become crusted or dry up and leave faint reddish stains. The course of herpes simplex is about 7 - 14 days. The site of the infection is the posterior root ganglion. The skin is the secondary site of infection. The lowered resistance of the body and skin due to injury, illness, drugs, pyschosomatic stress etc. predispose the body to an attack by the Vericella-zoster virus.
Cutaneous lesions develop three days after the onset of the attack.
The rash develops in the segmental distribution of the affected nerve root and consists of typical herpetic lesions. The lesion develops in several crops, each crop lasting a week or so. Ultimately the lesions rupture or dry up to form crusts which sloughs off leaving temporary pigmentation and faint scarring. The lymph glands near the affected area may be enlarged and painful. The attack lasts 2 to 3 weeks.