Sorry for the confusion around this information. HIV is not commonly passed to the person giving oral sex. This means we don’t usually see this as a way that HIV is passed, but it is possible to get HIV given the right conditions.
Usually HIV does not live in the mouth because enzymes in the saliva inhibit or kill the virus. When giving oral sex, vaginal fluids or blood could get into the mouth. If the person giving oral sex has bleeding gums, open areas in or around the mouth or has had recent dental work or tooth extraction, and there was enough blood present then HIV could be passed on. The risk would be higher when a woman is menstruating.
Dental dams or a condom cut longwise are barriers than can be used to lower risk.
You might want to check out “Know Your Chances” to get more information about ways of having sex and the chances of getting an STI.
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