Asked by: Anonymous
It is possible to have an extremely mild case of chicken pox as a very young child without producing enough antibodies, so leaving you open to subsequent doses. Generally though, one proper dose of chicken pox will set you up with life immunity.
However the varicella zoster virus, which causes chicken pox, is never fully eliminated from the body and can flare up in immuno-compromised adults to cause the quite different disease of herpes zoster (shingles).
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