I think you're over-analyzing all this, and I don't agree with some of your premises. For one, the likelihood of current or past HPV, of any type including HPV16, rises with age. There is no reason to suppose that older partners are any less likely to have had HPV of any particular type -- the opposite is true. In other words, I don't see partner age as having any bearing on HPV disclosure. Also, immune deficiencies probably do not increase risk of catching HPV. People with soem types of serious immune deficiency are more likely to have overt HPV manifestations (warts, more rapid progression toward cancer, less effective treatment), but not in likelihood of catching the virus. In any case, the natural modest decline in immune function with age has no known effect; and if someone you date has serious immune deficiency due to chemotherapy, cancer, HIV/AIDS, etc, most likely you will know it. So I also do not think this is an important consieration, and I disagree with your intent to disclose your past HPV to older partners, nor should you insist they be vaccinated against HPV. Indeed, HPV immunization is never recommended beyond age 40-45 (and therefore their health insurance probably wouldn't pay, meaning self-pay of $600 or more).

Beyond that, your questions are speculative -- based on an assumption that you might have an abnormal pap in the future, which probably is unlikely. Indeed, after 3 normal pap smears beyond a certain age (I forget whether guidelines currently state 30, 35, or 40 years), paps no longer are recommended, because new abnormalities are so rare. Discuss this with your gynecologist when you have your next pap. (That said, I'm not sure what the guidelines say about women who have had a past high risk HPV infection. But even here, I doubt twice yearly paps are necessary so many years after the initial abnormality.)

In summary, assuming you have no further abnormal paps -- or if you are of an age at which your doctor no longer advises pap smears -- I see no need for you to say anything about your past HPV. All this, or course, is in the context of disclosure for health reasons, HPV prevention, etc. Many couples discuss past partnerships and STD experiences, as part of an evolving relationship and trust. But this is a relationship issue, unrelated to health except indirectly.

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD

 
It seems there is some misinterpretation with my question - I apologize, I was limited to a word count so I couldn't explain in detail. Let me try again. 

--- I agree with you, the likelihood of having HPV increases with age (I'm asking about someone who is slightly older with very few past sex partners. For example, someone who has just had a divorce). This makes them less likely to have acquired HPV16. 
--- I also agree that age has no bearing on HPV acquisition, I'm asking about age influencing the ability to clear an HPV infection so that it does not progress to cancer.
--- I also agree that I don't think I'll have another abnormal pap, but I think HPV can still reactivate outside of cervical abnormalities. 
--- I had no idea the vaccine would be that expensive at older ages. Thank you for informing me about that. 

The reason Im specifically asking about older age and limited past exposure to HPV16  is because, given my very limited bio background, I remember learning that humans need naive cd8 T cells to fight off NEW viral infections (no previous encounter thus no memory T cells). I also recall learning that after age 40-50 the thymus is pretty much done outputting new naive T cells. I understand that naive cd8 and cd4 T cells are still circulating well after thymus atrophy, but not too sure for how long or at what age the limited cd8 t cell count starts to matter in terms of encountering a NEW strain of high-risk HPV. This is where my "disclose after age 50" logic came into play. I was curious if thymic atrophy and lower naive cd8 T cell count was significant enough in late 30s and early 40s to SIGNIFICANTLY put someone risk of not clearing HPV16.

You're going far beyond where the science allows. I am unaware of any data that older persons clear HPV any less rapidly than younger ones. You cannot extrapolate safely from a physiologic observation like T cell function as the thymus regresses with age and the immune response to any parrticular infection. At least if such a connection exists for HPV, it is not general knowledge among STD experts.

You'll probably never encounter a partner in whom it is certain they never were exposed to HPV16. Or any of the other HPV types you may have had (since most people have multipe infections during their sexual "careers"). Anyway, you'll probably never have a reactivation. And what will it matter if you do and a partner acquires HPV16 from you? The large majority of infections never cause symptoms and remain asymptomatic. Don't overreact just because you happened to be in the unlucky minority:  the vast majority of HPV16 infections never become apparent.

Bottom line:  This additional information doesn't change my opinions or advice about disclosure to future partners.