The Varicella virus a shortened name for the Varicella-Zoster virus (VZV) is the pathogen responsible for both chickenpox and shingles. The idea that one virus could cause two fairly different illnesses can be rather confusing. Hopefully this article will help clear up the fog surrounding this strange virus.
Fact: The Varicella virus was first described in the 9th century
The famous Persian physician Rhazes first described it as a mild form of smallpox (he was actually looking at chickenpox). He noticed that contracting this mild smallpox didn't protect against the development of epidemic smallpox.
Fact: VZV is a member of the Herpes virus family
There are eight viruses in the Herpes family, also including Herpes Simplex Virus 1 (causes cold-sores) and Herpes Simples Virus 2 (causes genital herpes). Not to worry, though. VZV won't cause cold-sores or herpes lesions, nor is it sexually transmitted.
Fact: Most people will get chickenpox only once in their life
Unlike viruses like rhinovirus or influenza, VZV mutates very slowly. Because of this, there are very few strains comparatively. Once your immune system fights off a certain virus strain it is nearly impossible to become re-infected with the same strain because your immune system recognizes it and kills it before it has time to become established. Since there are so few strains of VZV out there the chances of encountering a different strain and therefore developing chickenpox again are incredibly slim.
Fact: Once infected, the Varicella virus never leaves the body
Most viral infections are eventually cleared by the immune system. Many of the herpes viruses, including VZV, are capable of hiding from the immune system indefinitely. They do this by entering an area of the body which the immune system doesn't patrol: the nervous system. The Varicella virus is particularly adept at inhabiting the dorsal root ganglia, nerve bundles along the spinal cord which allow the skin to communicate with the brain.
Fact: Shingles is a condition that results from reactivation of VZV
When the Varicella virus lies dormant in the dorsal root ganglia it is said to be in latency. Certain factors can cause it to come out of latency including advancing age, stress, and other immuno-compromising states. This reactivation results in the condition known as shingles. A shingles outbreak usually lasts between 4 and 5 weeks, causing a blistered rash localized to the trunk that eventually heals on its own. Any other reactivation of the virus will always result in a shingles outbreak, never chickenpox.
Fact: Shingles isn't nearly as contagious as chickenpox
While chickenpox can be spread by inhaling infected droplets spread by coughing as sneezing or by touching pustules of the rash, shingles cannot be spread so easily. The only way spread the Varicella virus through shingles is by touching the fluid within shingles blisters. What's interesting, though, is that if someone with shingles infects someone who has never had chickenpox, that person will develop chickenpox instead of shingles. However, if someone with shingles is in contact with someone who has had chickenpox, that person will be unaffected since a shingles outbreak can only occur as the result of the reactivated Varicella virus in their own body. Shingles outbreaks can occur again and again, often causing painful nerve damage. Although there is no cure for shingles, there are many natural pain management methods. Be sure you know the specifics about shingles, especially as you age, to prepare yourself for a potential outbreak.