Can You Contract HIV Having Oral Sex?

I wanted a simple answer, but I learned that in the world of microbiology and infectious disease, nothing is simple. Let me share some of the highlights and principles with you. At the end of the article, is a list of terms and their definitions.

There is Still A Lot We Don’t Know
There is a lot of confusion and fuzzy answers about oral sex, and even men who use oral sex as an avenue to AVOID HIV infection continue to worry about transmission. (16) We know even less about the rate of HIV transmission from women to women (WSW) As one researcher noted:

“It is unconscionable that after 15 years of the HIV epidemic, HIV+ women still don't have accurate information about risk in order to know what to do or not do sexually with their female partners. A comprehensive HIV prevention strategy uses a variety of elements to protect as many people at risk as possible. Accurate information on female-to-female sexual transmission and HIV incidence, as well as what factors influence risk taking among WSW, will be key to protecting women who have sex with women.” http://www.caps.ucsf.edu/wsw.html

Infectious Diseases, Like People, Have Life Stages

Not all stages of infectious diseases are equally infectious. This is true of a variety of STI’s (Sexually Transmitted Infections). The notion of ‘stages’ in the HIV virus is an important breakthrough in understanding why different studies provide different answers to questions of transmission.

Not All People Contract Viruses and Bacteria When Exposed

We know this of course, from the common cold. Deliberately exposing a group of people to the cold virus will cause some of them to get sick, while others won’t. Why? Overall health as well as current and chronic stressors are some of the reasons. Depressed people who aren’t eating and sleeping well are also more vulnerable. Even life events like getting divorced can negatively impact your immune system, leaving you more susceptible. Ornstein, a researcher studying heart disease, found that even when not controlled for the severity of the heart condition, patients with good marriages survived at a higher rate than other. The same is likely to be true of those exposed to HIV.

Viruses Need Access

Like an open window that lets in mosquitoes, a tear in the skin, an open sore or gum disease create access points. Some skin tears are microscopic. Some are hidden from view in the recesses of the mouth or vagina. Some appear healed, but actually aren’t, like genital piercings some people have and wear small bar bells in. The constant minor friction continues to create minor microscopic openings for the HIV virus. It was one surprise researchers found: men who had piercings with bar bells had a higher rate of contracting HIV from a partner through Insertive Oral Sex (IOI) (see definitions below for more details).

People Don’t Tend To Practice Just One Sexual Behavior

By and large, if a person has oral sex, they often include other sexual behaviors with the same partner, such as sexual intercourse or anal sex. In one study, for example, more than 90% of those who reported engaging in unprotected receptive oral sex also reported having anal sex. (6) Of 513 “Men who have Sex with Men and Inject Drugs” (MSM/IDU), 43% reported having sex with women as well. In addition, 45% shared needles and most were poly-drug users. (12)
There are exceptions, of course, to the tendency to have more than one sexual practice. Female sex workers addicted to crack cocaine are more likely to practice strictly oral sex. They also have a higher rate of HIV infection resulting from the oral damage done by the cocaine use and smoke (and also probably as a result of the sheer volume of men they can service through oral sex alone). However, keeping these exceptions in mind, reports of transmission strictly through oral sex are often suspect.
Some researchers also hypothesize that there are likely to be certain differences in men who only practice oral sex compared to men who have a larger repertoire of sexual activities. (2)

People Don’t Tend To Be Reliable Reporters of Sexual Behaviors

Here are a few of the numerous reasons:

Faulty Memory
They may not be intentionally lying. Sex is an “altered state of consciousness,” and what one remembers in “normal waking state” maybe be different then when ‘getting it on.’ Some recall having "blacked out" at some point during sex. (2) Recreational drugs or alcohol use can also clouding the memory. There is also “recall bias,” a phenomenon probably more common today than 20 years ago. After years of receiving “safe sex” messages, subjects might begin to selectively “recall what happened” in a more “safe sex framework.” In one study from Holland in 1992, 55% of HIV positive subjects later retracted their initial story and in face-to-face interviews stated that they indeed had higher risk exposures to the HIV virus than they initially reported. Given what we know about people who underreported their risk, someone wanting treatment or asking for counseling may feel uncomfortable talking about what they actually DID instead of what they should have done. Maybe they feel stupid for having unprotected sex and say that they didn’t. Maybe they truly don’t remember. Regardless of the reason, it is important for researchers to address all the reasons why higher risk behavior can be underreported, causing the over-reporting of HIV transmission through oral sex alone.
Drug and alcohol use itself is correlated with riskier sexual behavior. Men who reported having used marijuana, poppers, hallucinogens, cocaine, or amphetamines in the 6 months before study enrollment in one study, were significantly more likely than men who did not use such drugs to report unprotected anal sex during that same period, regardless of the HIV serostatus of their partners. Heavy alcohol use was significantly associated with unprotected receptive anal sex with partners of unknown status and partners positive for HIV antibodies. Alcohol abuse was also associated with unprotected insertive anal sex with partners of unknown status. (6) Sex while high on crack cocaine was also the strongest positive association with HIV in one study of the behaviors among urban young men who have sex with men. (7) Cocaine use is also higher with prostitutes. (8,9,10)

Ego-Dystonic Behavior
What we do sexually and what we admit to doing is often not the same. Research subjects may be reluctant to admit particular behaviors that are unacceptable to them. Given the stigma attached to homosexual behavior, subjects might deny that they had sex in that way. STI’s are linked to HIV serocontraction (14, 15) and may suggest particular behaviors, like anal sex, that would otherwise be denied by the person.

Misattribution
A person might not define the behavior the same way a researcher would. For example, “nudging” is a practice of pushing a penis just into the opening of the rectum. When asked whether a person has had anal sex, a person who has had “nudging” might say “no.” Other subjects might consider having anal sex “just one time” as “not really having it.” Another might not consider it “oral sex” unless ejaculation occurred.

Sexual Ignorance
Sexual ignorance is also rampant. “I couldn’t be pregnant because I didn’t sleep with him” actually means that he left after the vaginal penetration, and didn’t spend the night.

Nervousness
Sexual research can also make people nervous, and that nervousness can create confusion with terms that are already confusing. Sometimes the fear of HIV itself can create the pressure to deny engaging in risky behavior. In one study, only after finding out that they were HIV negative could 25% of one group report engaging in sex acts as well as oral sex. (2)

What To Look For In Research Studies

So, given all these variables, I would suggest you keep certain elements in mind when reading literature regarding HIV transmission through oral sex:

(1) There are many ways to do research, and some are more reliable than others. In general, look for research studies that are conducted in person with experienced epidemiologist.
(2) A lot of ultra-detailed questions designed to elicit all kinds of possible exposures are usually more accurate than general questions.
(3) Repeat interviews with the same subjects are also more reliable than single interviews.
(4) Face to face history-takers, with in-depth, longer interviews, will be more reliable than results obtained through paper-and-pencil multiple-choice questionnaires or phone interviews.
(5) The best history-takers are also familiar with the subcultures and jargon of their research subjects. These skilled researchers are likely to produce results that provide more accurate findings than inexperienced ones.

Keeping all this in mind, let’s look at some of the overall findings:

• It is possible to get infected with HIV through oral sex. The risk is not zero. Depending on the population being tested, the rate has been anywhere from 0% (17), 1% (1,2) to as high as 7% in some populations. (3)

• The risk of HIV infection through oral sex is extremely low, but this again depends on a number of individual health factors listed above.

• Unprotected oral sex carries a much lower rate of infection than does other types of unprotected sexual activity. However, oral sex is seldom practices alone.

• Many other STI’s, such as syphilis and gonorrhea can be transmitted much more easily through oral sex. HIV should never be a person’s only concern when deciding on which sexual practices to engage in.

Studies Reporting Extremely Low Risk

An excellent paper from a Spanish publication detailed findings looking at serodiscordant (different HIV status) couples, who were heterosexuals, and they evaluated risks of HIV transmission through unprotected oral sex. In over 19,000 unprotected oral-genital contacts with HIV-infected partners, in which the total number of episodes between individual partners were several thousand, there was not a single case of seroconversion to HIV. (13) This included both infected women and infected men, but the majority of the population in this study was infected men. To quote the researchers:

“When you look at studies of serodiscordant couples, you have to remember that they had to remain serodiscordant for some time before being identified. This means that they had sex for some period of time and managed to still have the negative person stay negative. So whatever they were doing may not be reflective of serodiscordant couples in which the negative person became infected relatively quickly, or of people who are having multiple partners.” (2)

Another published study that showed that among 239 men who practice exclusively fellatio, not one HIV infection had occurred.(5) In a more recent work interviewing over 363 men, with about 30% of them reporting having sex with HIV-positive partners, again no infections were found. This represents over 5,000 acts of oral sex, with or without ejaculation. These men were all recruited from HIV testing sites, that tend, in general, to include very high risk subjects.

The Macaque Model

While we can ask people about their sexual behaviors, animal data is mentioned. Using Macaque monkeys, researchers demonstrated that if you swab tonsillar tissue or expose macaques to SIV, (a monkey equivalent to HIV) via oral mucosa, infection can occur.

On the other hand, I think that the studies in which comparisons are made of the efficacy of SIV transmission through oral, anal, vaginal, and intravenous routes are potentially flawed. SIV is a different virus from HIV. In addition, it was easier to induce transmission orally in monkeys, even non-traumatic oral transmission, than it was to cause SIV through anal exposure. This does not mimic the behavior of the HIV virus in humans.

The Mouth Isn’t Very Friendly to HIV

Overall, a healthy mouth is not usually a very hospitable place for the fragile HIV virus (see “Is a Dog’s Mouth Cleaner than a Human’s” in this folder). Certain strains of bacteria that occur naturally in the human mouth can snare the HIV virus and even snare infected cells, according to researchers at the University of Illinois at Chicago College of Dentistry. They reported their findings at the 104th General Meeting of the American Society for Microbiology.

In laboratory tests, researchers found that the bacteria latches onto the sugar coating on the envelope that encases the virus particle and blocks the infection. The bacteria also binds the sugar coating on immune cells, causing them to clump - a feature that could render those harboring HIV incapable of infecting other cells. http://www.news-medical.net/?id=1885

Getting Clear On Terms

The following are a list of terms I’ve come across in researching this topic and offered as a reference to you. HIV research is constantly changing. Never rely on old data when educating yourself. See what new research is out there. Hopefully, this will help:

IAS = insertive anal sex. The rate of HIV transmission to an HIV-uninfected person who is the insertive male partner in anal sex, when the receptive partner is HIV positive.

In plain English: Having anal sex with an HIV positive partner when you are not, and the risk of you becoming infected.

“IOI”= is the risk of HIV transmission to an HIV-uninfected person who is the insertive male partner when the receptive partner is HIV positive. Insertive oral intercourse refers to inserting your penis into someone’s mouth.

In plain English: This is the chances of becoming HIV positive when someone who is infected gives you a blow-job.

PEP= post-exposure prevention and post exposure prophylaxis with antiviral medications. Prospectively--before their infection status was known. Post exposure, after you were exposed to the virus. Retrospectively, when they were queried in great detail about all of their potential HIV exposures from three months prior to their last negative HIV test all the way through their first positive HIV test.

In plain English: You ask people who you now know are HIV positive what sexual behaviors they engaged in for the three months PRIOR to the last NEGATIVE HIV test.

'Per-partner' infectivity = refers to the risk with a given partner, uncontrolled for activity level (regardless of how active the couple is). This should be distinguished from the risk of a single sex act ('per-contact' risk).

Protected receptive anal sex - = what is the risk of HIV transmission to an HIV-uninfected person who receives anal sex from an HIV positive partner, while this person is wearing a condom? Receptive anal intercourse refers to receiving someone else’s penis in your anus.

English: What is the risk of you getting anal sex if your HIV infected partner wears a condom.

“ROI”= is the risk of HIV transmission to an HIV-uninfected person who performs oral sex on an insertive male partner who is HIV positive. Receptive oral intercourse refers to receiving someone else’s penis in your mouth. ROI refers to your chances of becoming HIV positive. Receptive oral sex with HIV-positive or unknown serostatus partners was 0.04 percent.

In plain English: This is the risk when you don’t have HIV, but you give a blow-job to someone who does.

Seroconversion – The process of HIV transmission from uninfected to infected. In HIV/AIDS research, seroconversion refers to the development of detectable antibodies to HIV in the blood as a result of HIV infection. A person who goes from being HIV negative to HIV positive is said to have seroconverted or is a seroconverter. A seroconverter is a person who has had one or more HIV blood tests (repeat tester) with negative results and who then, as a result of HIV infection, receives a positive HIV blood test result. The initial negative serostatus has converted to positive serostatus.

In Plain English: Sorry, no translation here.

SEROCONVERSION PERIOD
(See also SEROCONVERSION)
In HIV/AIDS research, the seroconversion period refers to the period of time it usually takes to develop detectable antibodies to HIV following infection with HIV. In 75% of persons, antibodies are produced in 4 to 8 weeks; in almost all persons, antibodies are produced within 14 weeks.

The seroconversion period is frequently described as the “window period.” It is very significant in relation to the timing of HIV tests. Persons who are tested during the window period may receive a negative HIV test result although they may IN FACT be infected with HIV. Persons disclosing HIV-related risk factors in the 14 weeks before testing negative for HIV are encouraged to be retested at the end of the window period.

The length of the seroconversion period depends on what infection the person has. For example, with the human immunodeficiency virus (HIV), the seroconversion is usually between 1 and 3 months, although it can be as short as 2 weeks or as long as 6 months. During the seroconversion period an infected person can infect others (even though no detectable signs of infection may have developed yet).



Reference:

1. Page-Shafer K, Shiboski CH, Osmond DH, et al. Risk of HIV infection attributable to oral sex among men who have sex with men and in the population of men who have sex with men. AIDS. 2002;16:2350-2352.
2. http://hivinsite.ucsf.edu/InSite?page=pr-rr-05
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4.http://hivinsite.ucsf.edu/InSite?page=pr-rr-05&doc=pr-rr-05-05
5. Page-Shafer K, Shiboski CH, Osmond DH, Dilley J, McFarland W, Shiboski SC, Klausner JD, Balls J, Greenspan D, Greenspan JS. Risk of HIV infection attributable to oral sex among men who have sex with men and in the population of men who have sex with men. AIDS. 2002 Nov 22;16(17):2350-2.
6. http://www.hptn.org/web%20documents/
Publications/bkbaselineajph.pdf
7.http://www.nyc.gov/html/doh/downloads/pdf/dires/epi-jaids-20040415.pdf
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Abstract
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JL Evans, JE Balls, J Klausner
(15IAC)
Abstract
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(15IAC) Abstract