Welcome to the forum. Thanks for your question. I'm sorry to hear of your situation -- this is a tough deal to be going through and I understand your concerns. I'll try to help.

If your assailant has HIV, this obviously was a high risk exposure, and until you know, it is right that you were prescribed post-exposure prophylaxis (PEP). I'll add at the outset that it is likely that the doctor who prescribed it has more experience with HIV exposures and prescribing PEP than Dr. Hook or I do. To my knowledge you are being treated with the best PEP drugs. However, if your doctor is not an infectious diseases specialist or otherwise highly experienced in managing and preventing HIV, you should ask for referral to such an expert to assist in your management.

From research in animals, PEP is believed to be virtually 100% effective, especially when admininstered within 24 hours. In addition, the large majority of HIV and infectious diseases experts have had no patients in whom PEP failed to prevent HIV. (As you will understand, it isn't possible to do research in humans who are known to be exposed, i.e. to treat some but not all with PEP to learn its true effectiveness.) I cannot say whether "anyone" has acquired HIV after PEP, especially when administered this quickly. However, most experience is in people with much lower risk of infection, such as sexual exposures. Whereas unprotected sex typically has less than 1 chance in a thousand of transmitting HIV, the risk probably is a lot higher after an injection exposure like yours. To my knowledge, there are no data on which to put a percentage estimate on your risk. While it is probably true that direct injection of infected blood into a vein is the most efficient mode of transmission, a needle stick under the skin may be almost as risky. For the rest of my reply, I'm assuming the needlestick was definite -- i.e. there is a clear entry wound, i.e. not mere suspicion that you you might have been stuck.

But of course you don't yet know whether he has HIV. Even in the highest risk urban areas, the large majority (over 95%) of injection drug users are not infected. If not, you can safely discontinue PEP; presumably that's why your initial prescription was for only the first few days. If he claims to be HIV negative, he still should be tested immediately. In this situation, I would recommend he have a PCR test (to check for viral RNA) as well as a duo test for HIV antibody and antigen. If he refuses voluntary testing, most or all states have laws that provide for court ordered testing in this situation -- but of course I do not know the legal situation in your area.

Even if it turns out he has HIV, at least two aspects are strongly in your favor, and maybe a third. First, your PEP was started very promptly. Second, the amount of blood in or on the needle probably was very small; the dose of virus makes a big difference in transmission risk. (Your situation is analagous to that of health workers who sustain sharp instrument injuries with HIV contaminated needles, scalpels, etc. Even without PEP, the large majority do not become infected.)

Third, if he is HIV positive positive you should also your assailant's detailed HIV status. Is he in medical care and on anti-HIV treatment? What is his viral load? As for HIV testing itself, most likely there are legal ways to learn this information even if he doesn't cooperate.

All in all, the odds are strongly in your favor, first because he probably doesn't have HIV; second because the risk might be quite low even if he does; and third because of prompt PEP. However, you also need to be asking these questions of the doctor(s) treating you, ideally an HIV/infectious diseases specialist.

I hope this information has been helpful, but let me know if anything isn't clear. Best wishes and good luck--  HHH, MD