linguistic:paraphrasing
Sexually transmitted infections

Some sexually transmitted infections (STIs), such as Chlamydia and human papillomavirus (HPV), can be transmitted through oral sex. Any sexual exchange of bodily fluids with a person infected with HIV, the virus that causes AIDS, poses a risk of infection. Risk of STI infection, however, is generally considered significantly lower for oral sex than for vaginal or anal sex, with HIV transmission considered the lowest risk with regard to oral sex.

There is an increased risk of STI transmission if the receiving partner has wounds on their genitals, or if the giving partner has wounds or open sores on or in their mouth, or bleeding gums. Brushing the teeth, flossing, undergoing dental work soon before or after performing 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 STIs 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. Because of the aforementioned factors, medical sources advise the use of condoms or other effective barrier methods when performing or receiving oral sex with a partner whose STI status is unknown.