[Skin involvement in zoster]

Zoster is a localised, generally painful cutaneous eruption that occurs most frequently among older adults and immunocompromised persons. It is caused by reactivation of latent varicella zoster virus (VZV). A common complication of zoster is postzosteric neuralgia (PZN), a chronic, often debilitating pain condition that can last months or even years. The risk for PZN in patients with zoster is 10 % - 20 %. Another complication of zoster is eye involvement, which occurs in 10- 25 % of zoster episodes and can result in prolonged or permanent pain, severe itch, facial scarring, and loss of vision etc. Prompt treatment with the oral antiviral agents acyclovir, valacyclovir, brivudine or famciclovir decreases the severity and duration of zoster-associated pain (ZAP). Additional pain control can be achieved by supplementing antiviral agents with analgesics, tricyclic antidepressants, and other agents, e. g., gabapentin. Efficacy of the therapy depends on its early initiation. Because zoster starts with unspecific symptoms, specific treatment starts late, as a rule 3 - 7 days after the beginning of virus replication, responsible for complications. A licensed zoster vaccine is a preparation of a live, attenuated strain of VZV, the same strain used in the varicella vaccines. However, its minimum potency is at least 14-times higher than the potency of single-antigen varicella vaccine. In a large clinical trial, zoster vaccine was more than 50 % efficacious for preventing zoster. It is also efficacious in reducing the severity and duration of pain and preventing PHN. Therefore zoster vaccination is recommended for elderly persons.