[Aces4]

Originally Posted by golfing eagles

Short answer, highly unlikely.

Your question is actually 2 questions in one:

1) Can someone who doesn't believe they ever had chicken pox have immunity?

Yes, since antibody studies show almost everyone who "never had chicken pox", actually did---a sub-clinical case, an exposure that triggered an immune response, etc.

2) Can someone who truly never had chicken pox or raised an antibody response, someone whose Varicella titer is zero have "natural immunity?

Highly improbable. The explanation would be fairly complex, but the simple version is that our immune system is constantly "experimenting" with theoretical antibodies against theoretical diseases. So technically, even if the Martian flu comes back with the samples NASA is planning on bringing back from Mars, there would be some people with "natural immunity". It's also a two edged sword. The "experimental" antibody could be harmful to ourselves, in which case it is supposed to be destroyed when it fails the test of "sameness" against our major histocompatibility complex in specialized immunologically active tissues. But when that "self-destruct" mechanism fails, we get autoimmune diseases, such as lupus or Hashimoto's thyroiditis. (Sorry, that was the simple version)

We have an interesting situation in that our youngest son did not contract chickenpox in the early eighties when his siblings were sick with them. I encouraged him to get a titer to check his immunity when he began employment in a hospital setting. He had immunity. His grandmother was the only one of eight siblings not to contract chickenpox when they were all ill with the pox. She raised a large family and we all had chickenpox at one time but she never contracted them and at a very ripe old age passed away without any history of shingles. Always made us wonder.