Oral Info: A Gay Men's Primer on Oral Sex and STDs

By Elizabeth Boskey, Ph.D. M.P.H. C.H.E.S.

Most of the safer sex information targeted at gay men these days focuses on just saying no to bareback sex. And with good reason: The majority of new HIV cases among men who have sex with men are transmitted via unprotected anal sex. While the primary message about safer anal sex is pretty clear—don't have unprotected anal sex if you don't want to contract HIV and other STDs—messaging around oral sex has traditionally been murkier. Want to cut through the fog and find out exactly what you can and can't catch from oral sex? Read on.

A lot of people equate unprotected oral sex with "safe" sex, but they're wrong. Although oral sex is certainly far safer than anal sex in regards to transmission of HIV, it is definitely not an infection-free ride. Many sexually transmitted disease pathogens are perfectly happy to jump from the mouth to the genitals and vice versa. While the majority of gay men choose not to use condoms for oral sex, it is nevertheless important to separate fact from fiction to help you make informed decisions.

Is HIV transmission through oral sex an urban myth propagated by men who don't want to admit they had unprotected anal sex? Maybe, maybe not. Although oral sex is a much lower-risk behavior than anal or vaginal intercourse, some studies have concluded it is possible to transmit HIV through oral sex. It's far from common, and several health departments consider it a low to moderate risk activity, but it is possible. In other words, don't panic, but don't assume you could never get HIV from oral sex.

The risk of HIV transmission via oral sex is increased if the person performing the oral sex has cuts or sores in his mouth, if the person receiving oral sex has other sexually transmitted diseases, or if ejaculation takes place in the mouth. This risk is primarily for the person performing the oral sex—saliva alone is extremely unlikely to transmit HIV, and so, unless the person performing oral sex has lots of blood in his mouth from dental surgery or other trauma, oral sex is a low-risk activity for the receptive partner. While many gay men do not use condoms for oral sex (or dental dams for rimming), it's important to note these are effective ways to even further reduce the low chance of transmitting HIV through oral sex.

Gonorrhea and Chlamydia
Both gonorrhea and chlamydia can be transmitted by oral sex, and, unlike with HIV transmission via oral sex, the risk of these two bacterial diseases really does go both ways. Unfortunately, physicians rarely test for either pharyngeal (from oral sex) or rectal (from anal sex) cases of these two bacterial STDs, so they often go undiagnosed and untreated. If you regularly have unprotected oral or anal sex, you should speak to your doctor about getting additional tests for gonorrhea and chlamydia in your throat and anus, but it is important to know that using a condom should be essentially 100 percent effective at preventing these two diseases.

If you are diagnosed with either gonorrhea or chlamydia, it is very important that you take your medication exactly as prescribed. Drug-resistant gonorrhea is increasingly becoming a problem in gay men, and it is possible that, if the number of resistant strains continues to rise, eventually one may develop that's untreatable. Don't be part of the problem—if you contract one of these diseases, take your pills like the doctor tells you to.

Despite the fact that, in general, different variants of the herpes virus are responsible for oral (cold sores) and genital infections, it is possible for the viruses to jump from location to location. HSV-2, the virus most often responsible for genital infections, can spread from the genitals to the mouth during oral sex, and HSV-1, the virus most often responsible for oral infections, can spread in the other direction. In other words, it is possible for the herpes virus to be transmitted during oral sex no matter which partner is infected. Although the use of condoms during oral sex reduces the risk of transmission, the herpes virus spreads skin to skin, so they may not be fully protective. You should also know that the herpes virus can be transmitted even in the absence of an outbreak, and that although treatment with medications such as acyclovir reduces the chance of transmission, it does not prevent it entirely.

Syphilis is on the rise in gay men across the United States. There is a body of research that suggests that that may be, in large part, due to unprotected oral sex, since very few men realize that syphilis can be transmitted in that way. There are areas of the world in which nearly half of the syphilis seen in men who have sex with men can be attributed to oral sex. Although syphilis is only contagious in the primary and secondary stages when symptoms are present, the sores often go unnoticed. You cannot assume that your partner does not have infectious syphilis just because you have not noticed the presence of a sore. Syphilis sores in the mouth may be particularly difficult to detect, and secondary syphilis in that area sometimes presents as something as seemingly innocuous as tonsillitis. If you have unprotected oral sex, getting tested for syphilis should be a regular part of your health checkups.

Hepatitis A can be passed during oral-anal sex (rimming), and it's possible that Hep B may be transmitted that way as well, although the data is less clear. Similarly, the research is mixed as to whether Hep B and Hep C can be transmitted via oral-genital contact. Some studies have shown transmission for individuals with extremely large numbers of sexual partners, while others have shown no association with oral sex at all. Fortunately there are safe and effective vaccines against both Hep A and Hep B, and they are easily available. Both vaccines are recommended for all men who have sex with men who weren't vaccinated as children.

HPV is best known as the virus responsible for causing the vast majority of cases of cervical cancer. This fact leads many men—and gay men in particular—to assume that human papillomavirus (HPV) infection is nothing they need to worry about. They're wrong. In addition to causing genital warts, HPV can cause penile and anal cancers as well as oral and throat cancers. HPV can definitely be transmitted from the penis to the oral cavity during oral sex, and it's possible that it could be transmitted the other way as well. Although very little research has been done in that area, at least one study has shown that one of the best predictors of having an oral HPV infection is having a regular partner with an oral HPV infection; the virus is very easy to transmit.


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