Everyone wants to know if they are at risk for HIV infection or any of a number of sexually transmitted infections for that matter. Do the behaviors in which they engage increase their risk of HIV infection? Can I get HIV from one unprotected sexual encounter? What is your risk of sexually transmitted infections? Unfortunately, their is a lot of debate as to what the answer to these question are. There are behaviors we know put you at risk for HIV infection and sexually transmitted infections.
- Receptive anal intercourse ("bottom")
According to the Guidelines for the Management and Post Exposure Prophylaxis of Individuals who Sustain Nonoccupational Exposure to HIV, ANCAHRD/CTARC Bulletin, February 2001, the risk of transmission as a result of receptive anal sex is somewhere between 1 in 125 to 1 in 31 or approximately three per cent. Other experts place the risk as low as 1 in 1300.Important Fact!
Infection can and does occur with just one unprotected sexual encounter. It's important to note that even though the risk is 1 in 1300, that one chance in 1300 can be the first time. - Insertive partner ("top") during anal intercourse
While the risk is about 10 times less than being the receptive partner, the risk is there and is real. And of course the same holds true...it only takes one time. - Vaginal intercourse - infected men to uninfected women
One study put the risk at about 1 chance of infection in 100,000 unprotected sexual encounters but again, the one might be the first contact you have. - Vaginal intercourse - infected women to uninfected men
Studies seem to confirm that the risk is quite low, about 1 in 200,000 but of course the risk is not zero. - Oral sex
Admittedly the risk of transmitting HIV during oral sex is extremely low, but the risk is there and it is not zero.Important Fact!
Keep in mind that beside HIV, oral sex can transmit other sexually transmitted diseases such has herpes and syphilis.
Which type of exposures carry the highest risk?
Certain exposure routes do offer higher risk of infection than others. Those exposures that carry the highest risk include:
- Sharing needles to inject drugs
- Receptive unprotected anal intercourse
- Vaginal intercourse
Breatfeeding & Child Birth
There are two transmission routes that have very high incidence of HIV infection - upwards of 1 in 4.
- child birth - transmission from infected mom to her unborn baby
- breastfeeding - transmission from mother to baby during breast feeding.
Fortunately, the risk for these two transmission routes can be decreased dramatically by good prenatal HIV care, expert HIV care during delivery, and HIV care for the baby after the delivery.
Important Fact!
Numbers and percentages really are just guidelines. Infection can and does occur after one unprotected sexual encounter or after sharing a needle once. The only way to know if you've been infected is to get tested. Percentages and numbers should not be a substitute for testing and safer sex.
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