Causes of Shingles

It is a known fact that it is the herpes zoster virus that causes shingles. It is also well known that this virus is also responsible for chicken pox in the human body. But what is not known is why the virus gets reactivated to cause herpes zoster.  The virus lies dormant in the nervous system and is actually never out of the body fully. According to experts during times of emotional stress, any immune deficiency or cancer, the virus gets reactivated and causes shingles.  However, in most cases of shingles the actual cause for the virus reactivation has never been found till date.