Search for a Cure: Don't Swallow: A Look at the Risks of Oral Sex

Beth Dillon of the Center for Disease Control's (CDC) most recent work focuses on determining the risk of oral sex transmission of HIV. But Beth was surprised this issue made front-page news. Her findings are far from the irresponsible headline grabbing stories screaming, "Priests with AIDS" and "Oral Sex is Dangerous" that were published after the 7th Conference on Retroviruses and Opportunistic Infections held January 30 to February 2, 2000 in San Francisco. Stories like these contribute to the belief that oral sex with someone who is HIV positive is dangerous. To those who have struggled to play it safe and decide from reading the headlines, "Oh well, if oral sex is dangerous too, I might as well do anything because the danger is all the same" -- don't! The headlines are simply wrong: there is a spectrum of danger from none (no sex at all) to very dangerous (anal receptive sex without a condom), and oral sex is not without risk, but it is still safer than other types of activity.

The real reason stories like these came out of the Retrovirus Conference is a combination of three factors: there was a great deal of important data presented at the conference, but little of it was easily understood so that it could be turned into a story. Some reporters lack integrity and care little about truth or relevance and care a lot about sexy headlines; and there is an underlying fascination with gay sex, straight sex or any sex at all. After all these years, sex still captures the media's attention.

The first thing wrong with the national headlines about oral sex being "dangerous" is that they are terribly misleading. The data presented at the retrovirus conference is not significantly different from earlier studies, all of which have concluded that the chances of oral sex transmitting HIV among those who are receiving semen in their mouth is very low.

The national headlines made the study sound like some new fact was uncovered that oral sex was somehow more dangerous than we had thought. But, in fact, the data shows, as has been thought all along, that oral sex is much, much safer than unprotected anal receptive sex, and that oral sex without ejaculation may be even safer. What is particularly disturbing about these headlines is that the data presented at the retrovirus conference is not significantly different from the many studies of this topic over the years.

To pick a few:

  1. 1989: Spitzer, P., et al; Transmission of HIV infection from a woman to a man by oral sex; NEJM; 320:251.

  2. 1990: Quarto, C., et. al; HIV transmission by Fellatio; European Journal of Epidemiology, 9:339-340.

  3. 1991: Lifson, R., et al; HIV seroconversion in two homosexual men after receptive oral intercourse with ejaculation; American Journal of Public Health, 80: 1509-1510.

  4. 1991: Clifford, L.; HIV seroconversion and oral intercourse; American Journal of Public Health, 81: 698.

  5. 1992: Keet, P.M., et al; Orogenital sex and the transmission of HIV among homosexual men; AIDS, 6: 223-226 (9 cases in a cohort of 102).

  6. 995: Edwards, S.K., et al; HIV seroconversion illness after orogenital contact with successful contact tracing; International Journal of STD and AIDS, 6: 50-51.

  7. 1996: Schacker, T., et al; Clinical and epidemiologic features of primary HIV infection; Annals of Internal Medicine, 125: 256-264.

  8. 1997: Bratt, G.A., et al; two cases of oral to genital HIV-1 transmission; International Journal of STD and AIDS, 8: 522-525.

  9. 1999: Robinson, E.D., et al.; Oral sex and HIV transmission; AIDS, 1999 16; 13(6); 737-738

Each reaches the same conclusion: oral sex can, under certain circumstances, transmit HIV; it happens rarely; among those who get HIV (which is itself a relatively small percent of people having unsafe sex), a very small number got it from unprotected oral sex. This does not mean we should be reckless. It just means we should play as safely as we are able.

The Real Story

There are huge problems with all of these efforts to determine the safety of oral sex transmission with regard to gay men. First, there are a certain number of men who, regardless of what they say or what psychosocial methods are used to determine the truth of what they say, will never admit to having anal receptive sex, as it is somewhat of a sub-cultural taboo. Sexism exists and one of its many manifestations is the tendency of a small percent of men to deny playing what some interpret as the "female" role in sexual behavior. There are also men with long-term partners who play out their "submissive" needs unbeknownst to their partners, with whom they may well restrict themselves to oral sex. And they aren't about to tell anyone that they do this. There simply is no provable way to tease out what percent of people who claim to engage in nothing but oral sex are people who would never admit to anal receptive sex, except to note that it is some percent, and therefore all of the data on oral transmission needs to be adjusted in this light.

Note that Ms. Dillon's study at the Retrovirology Conference concludes: "oral sex transmission is easily overestimated as other risks are not always revealed at initial interview. . . ."

In addition, there is a need to differentiate between people who are having receptive oral sex with ejaculation in their mouths versus those who do not go that far. People who have had recent oral surgery or other mouth sores versus those who do not, and there may also be a need to differentiate between types of HIV.

It may also be the case that people on medication are not likely to transmit virus: a very important study from the retrovirus conference, which was not widely reported, showed that among over 400 discordant couples (where one sex partner has HIV and the other does not) in which there was unprotected sex as a rule, NO HIV was transmitted when the person with HIV had a viral load below 1500. In this same study, it was shown that the higher the viral load the more likely HIV was transmitted during the study year. (Quinn, T.C., et al; Viral Load and risk of heterosexual transmission of HIV-1 among sexual partners, abstract 193 of the 7th Conference on Retroviruses and Opportunistic Infections, 2000. This material was presented at the conference's 27th slide presentation.)

This study is the first to document that lowering viral load with medications directly affects the rate of transmission in a major way. In fact, the conclusion of the study stated that " HIV-1 viral load was the major predictor of heterosexual transmission. . . ."

The Real Message

One person at the conference quipped we ought to change our question from "are you negative?" to "are you compliant?" given the data coming from the conference. The most important message coming from this conference about transmission is that people who are tested and successfully treated so their viral load is very low are unlikely to transmit the virus. This has dramatic implications for everyone -- it implies that we have a successful vaccine for AIDS -- antivirals. It has public health implications of a dramatic nature and it needs to be further studied and analyzed. It does not mean we should just pop pills and have any sex we want. That would be a big mistake because if HIV is transmitted under these circumstances; it probably is virus that our medicines won't be able to stop easily.

As far as oral sex goes: what everyone has been saying for a very long time is that it is much less dangerous than unprotected receptive anal sex. What's next?

As a practical matter, it needs to be understood that oral sex with a condom is safe. Oral sex to the point of ejaculation has a small element of risk to the receptive partner. Obviously if the partner is seronegative, there is no risk, and if the partner has a viral load that is very low, the risk is reduced. More studies of the risks of various sexual practices need to be funded, and studies which determine the danger of one kind of virus versus another also need to be funded.

What we are concerned about right now is the effect of the inaccurate sensationalized headlines. They might make some people think that oral sex is just as dangerous as anything else, so why try to stick to one versus the other. Oral sex is much, much safer than unprotected anal sex no matter what study you look at.

The Future

If you are negative, join a vaccine trial. If you are positive, check out the many new trials going on, especially trials of Immune-Based Therapies that might lead to control of the virus without drugs, or at least better control of the virus with drugs.

David Scondras is the founder and chairman of Search For A Cure. Scondras developed the nationally recognized HIV treatment series, "Reasons for Hope." All articles in the series are reviewed by expert HIV doctors and scientists and an HIV+ focus group for accuracy and understandability. The ideas expressed in this article are those of Search For A Cure and do not necessarily reflect the opinions of the Review Panel or AIDS Survival Project.

Search For A Cure is a not-for-profit organization providing education, promoting access and advocating the basic human right to safe and effective treatment for all people living with AIDS. If you have any questions or would like to receive the Reasons For Hope series in its entirety you can contact Search For A Cure at 617-536-2474, by e-mail at, or visit our web site at