Oral Sex and HIV: What are the risks?

One of the most common questions gay or gay-friendly physicians are asked is this one from one of our readers:

"I am a little unclear regarding the specific risks involved with oral sex between two males. Can you outline them for me? Also, how likely is HIV to be transmitted between oral sex?"

Rob Killian, MD responds:

Even among our three providers there is some debate on how best to handle this question. Let me tackle it this way:

From public health studies we know that men who have sex with men can get HIV from oral sex. It is the third most common way to get HIV in this community according to a well-respected public health community study out of San Francisco: (Google San Francisco Public Health and HIV statistics).

There is some risk of contracting HIV through oral sex. But attempting to quantify that risk is both frustrating and difficult. We know that anal sex, either as a top or a bottom (without a condom) is significantly more risky than receptive oral sex. There have been attempts to quantify the risk, but these have all proven to be inconclusive or to have mixed or inconclusive results... and transferring public health data to ones sexual encounter is very very difficult. This is science at its worst and at its best. The question is, honestly, impossible to answer in a black and white fashion.

Having treated HIV positive patients for over twelve years now I can, without a doubt, tell you that people can get HIV from oral receptive sexual encounters. Any of the HIV specialist providers I know will tell you that we all have some patients whose only risk for getting HIV was by giving blow jobs. But it is certainly a minority of our HIV positive patients.

So, none of us want anyone reading this to think that oral sex is without its risks. The other thing we all want to pass along is that HIV is not the only sexually transmitted disease to be worried about. With oral sex there is risk for Gonorrhea, Chlamydia, Syphilis, Herpes, HPV (warts) and Hepatitis--especially Hepatitis A. So, while oral sex is common, fun, and part of our sexual lives, it is not without some risk for STDs to consider.

Here is how I handle this personally. I try to get to know my partners first. I ask questions and try to be open and honest with them. I get to know them before even considering allowing them to come inside my mouth. And I get tested regularly.

This question alone is a good reason to have a physician or medical provider you can trust, to be honest with and to be able to openly discuss your questions, worries and risk. And one you feel comfortable going back to for repeated testing and repeated questions. Building a relationship with a medical provider is important. Being open and honest and expecting the same in return will add value to your life and your medical relationships.

Not one of us at Capitol Hill Medical want to prevent you from exploring your full sexual experiences and life. But, please, get tested, talk to your partners, talk to your healthcare provider and know the risks as best you can.

Dr. Chu or Dr. Dave do you have anything to add?


Dr. Vy Chu responds:

Hi Rob - thanks for taking a stab at this difficult and VERY common question.

Here's what we KNOW:

• People can and do become HIV positive from receptive oral sex (it has been documented in medical literature)

• Getting HIV from performing receptive oral sex is much less risky than than either receptive or insertive unprotected anal intercourse - let's call it a distant third

• As far as I know, there have not been any documented instances of HIV transmission from receiving oral sex (though certainly there is a theoretical risk)

Here's what we DON'T KNOW:

• We don't know exactly HOW much less risky oral sex is compared to receptive anal, or insertive anal sex; but for those demanding our best guesses, here is some data* listed by the CDC's January 21, 2005 guidelines on post-exposure prophylaxis for HIV ("post-exposure prophylaxis" means - you were exposed to HIV and we are going to give you meds to try to prevent you from actually getting infected):

*Note that I list this table under "What we don't know" because, despite the very certain-looking numbers in the table, these are still guesses and estimates (seriously, the authors of the study on which these numbers are based fully admit to making best estimates).

• We also don't know just how important some factors are in relation to each other in terms of oral transmission of HIV, such as: viral load of insertive partner, cuts in mouth/recent dental work/inflamed gums of receptive partner, whether the insertive partner ejaculated, etc. (though all these are theoretical contributors to risk of transmission)

In the end, as difficult as this question is to answer, it provides a great example of how best to navigate your risk. You need to talk to your sex partners, inquire about their HIV and STD status, and communicate openly about your concerns. So the more you know, the safer you can be. The less you ask, the higher your risk will be.

Rob, Dave, and I will always be here to help you navigate these risks...

- Vy Chu, MD