Claim: A risk factor for shingles reactivation is poor immune function.

Shingles , also known as herpes zoster , is a viral disease characterized by a painful skin rash with blisters in a localized area . Typically the rash occurs in a single stripe either on the left or right of the body or face . Two to four days before the rash occurs there may be tingling or local pain in the area . Otherwise there are typically few symptoms . The rash usually heals within two to four weeks ; however , some people develop ongoing nerve pain which can last for months or years , a condition called postherpetic neuralgia . In those with poor immune function the rash may occur widely . If the rash involves the eye , vision loss may occur .   Shingles is due to a reactivation of varicella zoster virus -LRB- VZV -RRB- within a person 's body . Chickenpox is due to an initial infection with VZV . Once chickenpox has resolved , the virus may remain inactive in nerve cells . When it reactivates it travels from the nerve body to the endings in the skin producing blisters . Risk factors for reactivation include old age , poor immune function , and having had chickenpox before 18 months of age . How the virus remains in the body or subsequently re-activates is not well understood . Exposure to the virus in the blisters can cause chickenpox in someone who has not had it before but will not trigger shingles . Diagnosis is typically based on a person 's signs and symptoms . Varicella zoster virus is not the same as herpes simplex virus ; however , they belong to the same family of viruses .   The shingles vaccine decreases the chance of shingles by about half in those between the ages of 50 and 80 . It also decreases rates of postherpetic neuralgia , and if an outbreak occurs , its severity . After 80 the vaccine is still effective , just less so . It contains the same material as the varicella vaccine , just at a higher dose . If shingles develops , antiviral medications such as aciclovir can reduce the severity and duration of disease if started within 72 hours of the appearance of the rash . Evidence does not show a significant effect of antivirals or steroids on rates of postherpetic neuralgia . Paracetamol , NSAIDs , or opioids may be used to help with the acute pain .   It is estimated that about a third of people develop shingles at some point in their life . While more common among older people , children may also get the disease . The number of new cases per year ranges from 1.2 -- 3.4 per 1,000 among healthy individuals to 3.9 -- 11.8 per 1,000 among those older than 65 years of age . About half of those living to age 85 will have at least one attack , and less than 5 % will have more than one attack . The disease has been recognized since ancient times .