Hello and welcome to healthcaremagic. Shingles or herpes zoster is caused by reactivation of Herpes Zoster Virus. Herpes zoster virus lies dormant in the spinal root ganglion and can sometimes multiply and travel along the nerves route, giving rise to grouped vesicular/fluid filled lesions, usually arranged in a stripe like patter, with a sharp cut off at the midline. Treatment is oral antivirals like acyclovir 800mg 5 times a day for 7 days, which is usually sufficient. Treatment can be extended for 2-3 more days if needed. I also advice in my patients of herpes zoster to apply a topical antibacterial ointment e.g 2% mupirocin twice daily, so as to prevent secondary bacterial infection. regards