(HealthScoutNews) -- Has the risk of contracting AIDS through oral sex been overstated?
That's the conclusion of a new study in which Spanish researchers examined 135 heterosexual couples who had unprotected oral sex an estimated 19,000 times during a 10-year period.
In each couple, either the man or woman was HIV-positive. Yet not one uninfected person contracted the virus that causes AIDS, the researchers say.
"It's a much lower risk than perhaps people have been led to believe," says Kimberly Page Shafer, an assistant professor of medicine at the University of California at San Francisco's Center for AIDS Prevention Studies.
"I'm not going to say people can't get HIV from oral sex, but it's a low-risk activity," adds Page Shafer, who was not involved with the Spanish research.
Vaginal and anal intercourse are the main sexual ways to transmit the AIDS virus. For years, oral sex was relegated to a gray area as scientists debated its risks. Most people who engage in oral sex don't wear condoms or use other types of protection, Page Shafer says.
Determining the specific risk of oral sex "has been a huge challenge," she says. "People have a repertoire of sexual behaviors, and they don't limit themselves to only oral sex."
Last year, Page Shafer reported at a National HIV Prevention Conference that her study of 198 gay and bisexual men who said they'd only had oral sex found that none of them became infected with HIV, even though some engaged in the practice with HIV-positive partners.
In the Spanish study, researchers in Madrid followed several hundred couples that included one partner who was HIV-positive from 1990 to 2000. Then the researchers narrowed the number to 110 women and 25 men who engaged in unprotected oral sex but wore condoms during other types of intercourse.
The results of the study appear in a recent issue of the journal AIDS.
The researchers, counting both fellatio and cunnilingus, estimated that 19,000 oral sex acts had occurred, and men had ejaculated in 34 percent to 41 percent of the fellatio acts. However, no HIV-negative partners contracted the virus.
Page Shafer says saliva appears to create an environment that is unhealthy for the AIDS virus.
Michael Allerton, HIV operations policy leader with the Kaiser Permanente Medical Group in Oakland, Calif., says there have been only a small number of confirmed cases of HIV transmission through oral sex.
"But it all depends on a lot of things," he says. "There's a lot of variables about whether transmission is going to occur. For example, the AIDS virus may more easily transmit through oral sex to a person with gum disease.
"While evidence continues to mount that oral sex is at much lower risk than other activities, the word 'risk' is still there," he adds.
Allerton cautions that even if the risk of HIV transmission is low, oral sex isn't risk-free. "You still can get gonorrhea, syphilis and herpes," he says.
Federal health officials acknowledge the risk of HIV infection through oral sex is less than compared to vaginal or anal sex, but transmission of the virus is still possible.
This information is not intended to be a substitute for professional medical advice. You should not use this information to diagnose or treat a health problem or disease without consulting with a qualified healthcare provider. Please consult your healthcare provider with any questions or concerns you may have regarding your condition.
