Hi Worried Guy 2 Thanks for getting in touch and sorry it has taken while to reply. There is the always a very small chance that you might be one of the people who get a false negative result. For an otherwise healthy male testing more than 12 weeks post possible infection the chances are much lower, in fact less than 1:1,000. Also, the chances of you passing it on through vaginal sex are about the same. Assuming you had sex more than once, the overall the chances of the test being wrong and you then, inadvertently, passing it on are probably 1:100,000. And this is all on the basis that you are HIV positive. Only about half of people infected with HIV get these symptoms. At this time of year about half of all people get symptoms like this from the flu or the common cold. So it's about 1,000 times more likely that your girlfriend has something other than HIV. My advice is to accept your negative HIV test for what it is and not worry about your or your girlfriends HIV status. I'm sorry that I can't give you an absolutely positive answer, but as I said the chances a very very low indeed. I really hope that this helps and if you want to discuss please don't hesitate to contact me again. Kind regards Gary Carpenter BioSure (UK) Limited