-fully protected from current exposure but not infected yet? I believe I read Dr. Hansfield or Hook mention that

-or fully protected from reinfection from an old virus?

2. Is reinfection in healthy individuals something that is uncommon? My concern would be that something would reappar if I had a night out of having beers, or had a week where I didn't eat as well, generally reducing my immune response? or are we talking that is has to be on a larger scale as in AIDS or other immunodeficiencies?

3. Is it common to have exposure without infection? What are the chances of being exposed to the cancer causing strains, 16/18? Do we all come in contact with them eventually. Can we build immunity without infection? 

4. Am I protected forever after having the immunization? I read ( believe from Dr. Hook or Hansfield) that after the second immunization, you are fully covered? Is that at 2 months, or just whenever you have the injection (as you can have them at 1-2 months). 

I just want to be secure that I won't pass anything on to anyone else as there's a lot of info out there on the subject. 

First let's be sure we're clear on terminology. Reinfection means catching a new infection with a particular HPV type if reexposed to it. The context of your question suggests you're also asking about relapse, i.e. previous infection suppressed by the immune system but now reactivating. Reinfection is uncommon even without vaccination -- that is, the immune system reduces (but probably does not eliminate) the risk of new infection if reexposed to the same type of HPV. The vaccine probably is highly effective in preventing reinfection, but has no effect on potential relapse of an infection acquired before immunization.

Second, your questions suggest you may be expecting more from the vaccine than it offers, and I have to wonder exactly why you have started the vaccine at age 30. Normally it is not administered after age 26, because new HPV infections are uncommon and therefore there is less benefit to immunization. And it will have no effect on any prior HPV infections you may have had, or the likelihood you will transmit HPV to future partners. However, now that you have had the first dose, I would recommend you complete all three doses.

To your specific questions:

2) Here is where I think you're asking about relapse, not reinfection. Given your age and sexual history, you can be sure you have been infected with HPV, probably more than once. Being vaccinated will have no effect on the potential for one of these infections may relapse. But even without immunization, most such infections stay dormant for life, i.e. not detectable with current test methods, never causing symptoms or disease, and not being transmissible to partners. However, all these things happen occasionally.

3) Yes, it is common to be exposed but not infected. That is, most episodes of sex with an infected person probably do not result in transmission of the virus. The cancer causing strains like HPV 16 and 18 are among the most common, so there's a very good chance you already have been exposed and likely infected with them (again, based on statistical probabilities for a 30 year old with several lifetime sex partners). However, there is no known immunity without infection:  that is, it is infection that results in immunity, not simply exposure.

4) Evolving data suggest that protection is very strong after only two vaccine doses. However, 3 doses probably is slightly better and is the only regimen known for sure to be 100% protective. You should plan on getting all 3 doses.

There is no guarantee that you won't transmit HPV to a future sex partner, but the chance is fairly low (with or without the vaccine).

I hope this information is helpful. Let me know if anything isn't clear.

HHH, MD

3. And, as far as reduced immunity goes, we're talking for people with major immuno suppressive issues such as AIDS/HIV, et cetera. Not referring to normal everyday stress, occasional drinking, etc.. ( I do not smoke)

Once again, Thank you.

2) Correct, the vaccine only protects against new infection with the types covered by the vaccine. You are a very typical example of why the initial studies of the HPV vaccines didn't enroll people over age 26:  at that age, too many (even those with many fewer partners than you) have already been infected with the vaccine strains and therefore would not be protected. More recent research has documented vaccine effectiveness in people age 26-40, but most experts would recommend against vaccination in people with your sexual history.

3) Correct about immunity. There is no evidence that day to day immune system stresses have any effect on HPV. Major immunosuppression like cancer chemotherapy or advanced HIV can promote HPV recurrence and more rapid progression to warts or cancer.

Thanks for the thanks. I'm glad to have helped. Anything else?

Thanks for the thanks. I'm glad to have helped. Best wishes to you.