HIV is found in body fluids of a person with the virus, whose levels of virus are detectable. The body fluids most likely to contain enough virus to pass on HIV to another person are: semen (including pre-cum) vaginal fluid anal mucus blood breast milk HIV is a fragile virus and does not survive outside the body for long. HIV is most commonly passed on through unprotected anal or vaginal sex. There is a very low risk of getting HIV through oral sex and there can be a small risk through sharing sex toys, which can be eliminated by using fresh condoms for each person using the toy.