Related Experiment Video
Updated: Oct 29, 2026

Ex Vivo Infection of Human Lymphoid Tissue and Female Genital Mucosa with Human Immunodeficiency Virus 1 and Histoculture
Published on: October 12, 2018
Oral sex and the transmission of viral STIs
Objective:
To review the literature on the role of oral sex in the transmission of viral sexually transmitted infections (STIs).
Method:
A Medline search was performed using the keywords oro-genital sex, and those specific to each infection. Further references from each article identified by Medline were also included, as were relevant references from "Current contents".
Conclusions:
Oral sex is a common sexual practice among both heterosexual and homosexual couples. The evidence suggests that HIV transmission can take place through oro-genital sex from penis to mouth and vagina to mouth. Case reports describe apparent transmission from mouth to penis although this appears less likely. The risk of oro-genital transmission of HIV is substantially less than from vaginal and anal intercourse. Receptive oro-genital sex carries a small risk of human papillomavirus infection and possibly hepatitis C, while insertive oro-genital contact is an important risk factor for acquisition of HSV 1. Oro-anal transmission can occur with hepatitis A and B. The transmission of other viruses may occur but is unproved. The relative importance of oral sex as a route for the transmission of viruses is likely to increase as other, higher risk sexual practices are avoided for fear of acquiring HIV infection.
Related Concept Videos
Sexually Transmitted Infections
Amebiasis
Genital Herpes
Herpes
Viral Hepatitis I: Introduction
Transmission-based Precautions I: Contact, Enteric, and Droplets
Contact Precautions:
Contact precautions are the measures taken to prevent the transmission of infectious agents, especially epidemiologically important microorganisms such as MRSA or influenza, primarily transmitted through direct or indirect contact with an...

