Chlamydia, human papillomavirus (HPV), gonorrhea, herpes, hepatitis (multiple strains), and other sexually transmitted diseases (STDs)—including HIV—can be transmitted through oral sex. While the risk of transmitting HIV through oral sex is unknown, it is suspected to be fairly rare.
Any kind of direct contact with body fluids of a person infected with HIV (the virus that causes AIDS) poses a risk of infection. The risk from most of these types of infection, however, is generally considered far less than that associated with vaginal or anal sex.
If the receiving partner has wounds or open sores on their genitals, or if the giving partner has wounds or open sores on or in their mouth, or bleeding gums, this poses an increased risk of STD transmission.
Brushing the teeth, flossing, undergoing dental work, or eating crunchy foods such as chips relatively soon before or after giving oral sex can also increase the risk of transmission, because all of these activities can cause small scratches in the lining of the mouth.
These wounds, even when they are microscopic, increase the chances of contracting STDs that can be transmitted orally under these conditions. Such contact can also lead to more mundane infections from common bacteria and viruses found in, around, and secreted from the genital regions.
