What are Shingles? also known as herpes zoster - is a condition that causes a painful rash or blisters on the skin.

It is caused by the same virus that causes chicken pox - the varicella-zoster virus. Anyone who has had chicken pox is at risk for herpes zoster, although it is not clear why some people's skin is affected while others seem to not get the condition even after having chicken pox.*

Researchers think that when some people get chicken pox, the illness lingers in the nervous system, only to be activated years later as herpes zoster.*