This is because HIV is normally present in low levels in the throat which are not sufficient enough to cause infection
. Secondly, the lining of the mouth and throat
are very resistant to viral infections such as HIV, so infection is unlikely if they are healthy. But, if there is bleeding wounds or gums in the HIV positive person’s mouth or on their lips, the virus may transfer through the blood into the mucous membranes of the other person’s genitals or into any cuts or sores they may have.