Question: how likely I get HPV from two protected sex (Penis in Vagina) for two women whose pap is generally normal? I do not care about low-risk strains of HPV.  If it is warts, I can get treated for it. No Big Deal.  it is been 6 months since I had the encounter. I did not show symptom yet. I guess I may not.

Welcome to our Forum. I'll be glad to comment.  The two exposures that you describe are low risk but, of course, we are talking probabilities, not guarantees.  Before I comment however, I need to point out that I can see little reason to care whether you acquired HPV or not from the encounters you describe.  Since the infection is so common, since complications are so rare, and since in the majority of instances the infection is self-limited and clears spontaneously over a few months, I see little reason for concern.  If you are concerned, while we can do little about the past, going forward the best thing you can do for yourself and for future partners is to take the HPV vaccine which is highly effective and safe. 

Here are the considerations related to the exposures that you have described:

1.  There are no precise estimates of the likelihood of acquiring HPV if you had sex with an infected person.  For all STIs however, infection is transmitted ONLY in a minority of cases, even in unprotected exposures and you used condoms.  .

2.   Research has clearly shown that condoms are the most effective way of preventing STI transmission, including HPV.  Your use of condoms reduces you risk for infection substantially (probably over 50%).

3.  While the PAP smear is an imprecise way of detecting HPV infection, that your partner have normal PAPs is good news and reduces you exposure risk.

4.  That you have not developed visible warts means that you will not. If you were going to develop warts from the exposure you describe, you would have by now. 

I hope this information is helpful to you. If you have additional questions or clarification is needed, please feel free to use your follow-up questions for this purpose.  EWH

How reliable is cytotoxic T cell response testing for finding the past infection?  

 can I get reinfected with the same strain if I am already infected? 

Cytotoxic T-cell testing is a research tool which has NO role in evaluating risk for HPV. 

People can be re-infected with the same HPV type if they have naturally acquired infection but it is rare.  The vaccine on the other hand is, for all practical purposed, completely protective for the types of HPV found in it.

The DNA vaccine is promising but still the topic of research.  I recommend the currently commercially available protein capsid HPV vaccine. The enthusiastic link you provide is provided by the company developing this vaccine, not an unbiased observer. 

Hope this helps.  EWH

It is difficult to provide a precise estimate of your risk- likely less than 1 in 5 (20% and probably far lower) but this is merely a guess.  There is no good way to provide this sort of calculation. 

I agree that t-cells are an important part of the host response to HPV infection although the efficacy of the currently available vaccines also correlate with antibody levels.  There are no good, widely available data on the use of measuring immune response (antibodies or cytotoxic T-cells) for determining protective effect of HPV vaccination.   These are research tools only.

This is my 3rd reply to your questions. Thus, as per Forum guidelines, this thread will be closed without further responses.  Take care.  EWH