How likely is it for a "top", negative guy to contract HIV from a "bottom" hiv positive guy?

I'm really interested in this guy and he just found out that a past partner is HIV +. The last time they did anything was beginning of August (before we ever met). The guy I am interested in was "topping" the positive guy, unprotected. I know the risk is lower, but never zero chance. He just had a HIV test a week or so ago and it came back negative; plus he had a urinary infection. I said to him that you are probably negative cuz if he had caught it, the urinary thing would have been worse. Is this true at all? And, how accurate are the RNA hiv tests? (I know it can take up to 3 months to show in the typical ELISA, but I read about an RNA/PCR test that looks for the DNA strand of HIV) Where can one get one? Thanks for any help

Really Worried and Upset =(

Thank you all!

The chance of HIV transmission from bottom to top is less than that from top to bottom, but not massively less. The risk is around the same as for both insertive and receptive vaginal sex. It sounds like your friend is playing with fire.

No, you can't tell whether he has HIV by how bad his "urinary" infection was. You should also know that nearly all "urinary" infections in otherwise healthy younger men are STIs, such as chlamydia and gonorrhoea. Unlike women, young men very rarely get bladder infections. Unfortunately, the presence of such urinary infections makes the likelihood of HIV transmission significantly higher.

I hope your friend is lucky, but it sounds like he needs to reevalute his attitude to safer sex. If you are contemplating having sex with him, it is important that you think carefully about safer practices too.

In Victoria (Australia) you used to be able to get PCR tests done, but the labs are reluctant to do them these days for diagnostic purposes. They were quite expensive - about A$200. If you are in the US I imagine they'd be even more expensive.

[Edit] Okay. As for the "parasite" thing, this sounds suspiciously like it's derived from the "theories" of Hulda Clark. You can read about her here: http://www.quackwatch.org/01QuackeryRela...

or here: http://en.wikipedia.org/wiki/Hulda_Clark

As for the PCR tests, there are two main types: qualitative and quantitative. Qualitative tests are used to determine if HIV is present, quantitative tests (much more common and also called viral load tests) are used to check how much virus is present and are used to monitor the course of HIV infection in someone who is already diagnosed. Quantitative shouldn't be used for screening for HIV because they read "undetectable" for a significant number of people who actually have HIV but who carry the virus in low numbers.

If your friend can find a clinic that will do a qualitative PCR he should ask carefully about the actual chances that a "negative" test is a true negative with the particular test they use. Before shelling out his money, he should also think about whether doing such a test will make any difference to his health, whatever the result. The results sometimes take a while to come through. He might be better off waiting a few weeks and doing a normal HIV antibody test which would provide a similar level of reassurance or otherwise.

Look, I realise you're dealing with some very confronting stuff here. I hope it all turns out okay, but you need to know that a "positive attitude to sex" is not enough to prevent HIV. Negotiating sexuality in the age of HIV is tricky especially for gay men, and requires informed and careful consideration of possible risks. You cannot do this during foreplay - the human brain is not designed that way. You have to do it beforehand . Safer sex is not an add-on - it should be the default position.

I'm sorry that you have to go through this. It is a hard thing to g through. I believe that it doesn't matter what position anyone is in, if someone with the virus enters the mucus membrane the virus is likely to enter it, especially if there is even the tiniest cut or opening to your blood.

Well it does take three months to detect HIV in a person's body because the virus has to take it's course to mutate and start killing cells and when it's killed a significant amount of white cells, that's when it shows up. It's good that he got checked and found out that he's negative, but tell him to continue to test. Wait until December and get checked again.

Also, I know that I may sound like I'm crazy, but HIV and AIDS are all caused by a parasite. I know this because I've done extensive research on parasites, because my health was declining and I found out it was parasites. It's an epidemic in the US and people don't even acknowledge it! So my suggestion for you and your friend, is to go to this website, and contact this Natropath. She is awesome!! I wouldn't recommend her if I didn't believe in her, and no I am not getting any commission or any other incentive for this. I just really want to help. Both of my siblings have type 1 diabetes and I found out it's also caused by parasites. SO please contact her, and get on a plan to rid him and you (if you are going to be sexually active) of parasites. She gives advice for free, but you have to join as a member, because if she didn't do that then everyone and their mom would be emailing her. www.herbalhealer.com. If you have any questions please please email me. Just be safe and good luck!

I feel kind of silly answering this way, but, do not believe a word that bigbadg says. Parasites have nothing to do with AIDS (or Type I diabetes). AIDS is caused by the HIV virus. The info given by Snout is very accurate. Usually the PCR test is only done after someone has shown to be positive, to monitor anti-viral therapy. After a baseline, showing how many replicates, the therapy is started, and a subsequent pcr is done and, hopefully, the replicates will be lower. I was told that if someone has not "sero-converted" (become HIV+) six months after exposure, then the individual had not been infected.

I'm not so sure about the "parasite" theory. Just stick to the virus idea - that's been proven.
I don't think it's possible to put a probablility factor on this sort of thing - ie what's the likelihood of someone getting HIV from someone else. Some people involve themselves in risky behaviour, and don't catch anything. Others do it once, and do catch something. I think in your case, regardless even of whether there's a risk that your partner could have undetected HIV, you should be wearing a condom EVERY TIME.
You're right, there's never a zero chance, and I don't think gambling with your health is a wise thing to do. Please use a condom!