HIV is transmitted through certain bodily fluids, mainly blood, semen, vaginal fluids, and breast milk, not through air, saliva, or casual contact, and it is dependant of high-risk behaviours, not sexuality, gender, etc. Gay men may be statistically more affected by HIV, not because of their sexuality, but because anal sex is more common among men who have sex with men, and it carries a higher risk of transmission. The lining of the anus is thinner and more likely to tear during intercourse, which can lead to blood-to-blood contact if one partner is HIV-positive, or semen is stuck inside. It can also happen between a man and a woman, again, depending if the act.
Please see below for probability of transmission and their corresponding high risk-behaviours. Anyways, carry on…
| Activity | Risk-per-exposure |
|---|
| Vaginal sex, female-to-male, no condom | 0.04% (1 in 2380) |
| Vaginal sex, female-to-male, no condom, undetectable viral load | 0% |
| Vaginal sex, male-to-female, no condom | 0.08% (1 in 1234) |
| Vaginal sex, male-to-female, no condom, undetectable viral load | 0% |
| Receptive anal sex, no condom | 1.38% (1 in 72) |
| Receptive anal sex, no condom, undetectable viral load | 0% |
| Insertive anal sex, no condom | 0.11% (1 in 909) |
| Insertive anal sex, no condom, undetectable viral load | 0% |
| Receptive fellatio (giving head), no condom, viral load not known | Estimates range from 0.00% to 0.04% (1 in 2500) |
| Pregnancy and childbirth, no preventative measures | 22.6% (1 in 4) |
| Pregnancy and childbirth, undetectable viral load | 0.14% (1 in 715) |
| Injecting drug use | 0.63% (1 in 158) |
| Needlestick injury with contaminated blood | 0.23% (1 in 435) |
| Blood transfusion with contaminated blood | 92.5% (9 in 10) |
