Varicella Zoster Virus
What we will be talking about in this post is the Varicella Zoster Virus (VZV), classified under herpesviridae meaning it is a type of herpes virus. It spreads via the air and close contact. This virus causes chicken pox in us and is usually a one time affair.
Why?
This is because the VZV is a DNA virus that transcribes its genome, from DNA to mRNA in the host cell nucleus. The presence of host cell DNA polymerase ensures that no mistakes will be made during transcription. This severely lowers the mutability of the virus meaning that once the body develops immunity against it (First chicken pox infection), new infection will not occur due to the ability of the immune system to recognise it easily and destroy it.
However, there is something else that is very important. During the first infection, when you are very sick, the symptoms are due to the lytic cycle of the VZV. At the same time however, certain cells are "reserved". In these cells, the VZV ONLY goes through the lysogenic cycle in them. These cells are the nerve cells.
Therefore after the initial infection you will never get chicken pox again however IF the virus resting within your nerve cells get activated, you will experience excruciating pain all over the body because nerve cells are spread all over.
Image of VZV
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