What is the risk of contracting AIDS if somebody has unprotected sex just once or twice (not knowing whether the other person is HIV + or not)?
To answer this question: it depends! First, keep in mind that you donít contract AIDS, but HIV, which is the virus that causes AIDS. Contracting HIV through unprotected sex depends on a number of things. First, you note that you do not know if the person was positive or negative. If he or she is negative, there is no chance that you will contract HIV from unprotected sex! But if he or she is positive, it depends on things like whether you were the insertive or receptive partner (receptive is more risky than insertive); if the sex is oral, vaginal or anal (with oral being least risky, vaginal more risky and anal the most risky); the viral load of the person living with HIV (with higher viral loads being more risky.) The bottom line: the only way you can know if you have contracted HIV is by going for a test. And always practice safer sex as this is the only way to make sure that you will not become infected through unprotected sex.