Primary HIV Infection Associated with Oral Transmission

Many persons have inquired about the results of a study presented as a poster at the 7th National Conference on Retroviruses and Opportunistic Infections, held January 30-February 2, 2000. The following questions and answers contain more specific information about the presented study results.

Question: What is this study about?

Answer:

This study, one component of a primary and recent HIV infection study called the Options Project, is funded by the Centers for Disease Control and Prevention (CDC) at the University of California, San Francisco. The purpose of this particular study was to ascertain the extent of HIV transmitted by oral sex among men who have sex with men who were identified with HIV within 12 months of becoming infected.

Question:

Hasn’t oral sex already been identified as a method of transmitting HIV?

Answer:

Yes. However, this is the most definitive study to date. Earlier studies have been published. (See a bibliography at the end of these questions/answers.)

Question:

What is the risk of HIV transmission from oral sex?

Answer:

The likelihood of transmission of HIV from an infected person to an uninfected person varies significantly depending on the type of exposure or contact involved. The risk of becoming infected with HIV through unprotected (without a condom) oral sex is lower than that of unprotected anal or vaginal sex. However, even a lower risk activity can become an important way people get infected if it is done often enough. The Options Project found that 7.8% (8 of 102) of recently infected men who have sex with men in San Francisco were probably infected through oral sex. Most of these men believed that the risk was minimal or non-existent.

Question:

What are the exact ways that HIV was transmitted in this study?

Answer:

Nearly half (3 of 8) of these cases reported oral problems, including occasional bleeding gums. Almost all (7 of 8) of these men reported to have had oral contact with pre-semen or semen.

Question:

How do you know if the study participants were telling the truth about their sexual history?

Answer:

Oral transmission of HIV is very difficult to single out as the only way that HIV is transmitted because few people engage exclusively in oral sex. A number of specific questions were asked by a trained evaluator. The participants’ risk behaviors were assessed by using clinical interviews, counselor intervention, epidemiologic interview, partner interview when possible, and final disposition of transmission risk. Of the 8 cases, 4 reported protected anal intercourse, without the condom breaking, with persons who were either HIV infected or had an unknown serostatus. Men in this study who reported that they were uncertain if the condom was used properly were eliminated from this study.

Question:

Was this a surprise finding?

Answer:

Yes and No. The percentage of recently infected men enrolled in this study who were probably infected through oral sex (8%) was higher than many researchers had thought likely or found in other studies. More media attention appeared to be placed on this particular study, probably because of the higher number of study participants. There appears to be evidence that higher risk activities (anal sex) among men who have sex with men is decreasing while lower risk activities (oral sex) among these men is increasing. Oral sex has always been considered a lower risk activity but is certainly not risk free.

Question:

What can be done to prevent HIV?

Answer:

The study results emphasize that any type of sexual activity with an infected person is a risk of HIV transmission. Oral sex with someone who is infected with HIV is certainly not risk free. Prevention of HIV is more important than ever. Some persons have indicated that they are less concerned about HIV because of new treatments and are being less careful. This study presents a wake-up call to everyone – that HIV is far from over and remains a serious, lifelong disease that is best to prevent. The surest way to avoid transmission of sexually transmitted diseases is to abstain from sexual intercourse, or to be in a long-term mutually monogamous relationship with a partner who has been tested and you know is uninfected. For persons whose sexual behaviors place them at risk for STDs, correct and consistent use of the male latex condom can reduce the risk of STD transmission. However, no protective method is 100 percent effective, and condom use cannot guarantee absolute protection against any STD.

Question:

Where can I get more information about transmission and prevention of HIV?

Answer:

CDC operates a toll-free, confidential National STD/AIDS Hotline which can assist callers with these types of concerns. The English service (24 hours a day, 7 days a week) can be reached by calling 1-800-342-2437; Spanish (8:00 am to 2:00 pm EST, 7 days a week) is 1-800-344-7432 and TTY service for Deaf and Hard of Hearing (10:00 am to 10:00 pm, EST, Monday- Friday) is 1-800-243-7889.

Bibliography:

Berrey M, Shea T. Oral sex HIV transmission (letter). J AIDS 1997; 475.

Bratt GA, Berglund T, Glantzberg BL, Albert J, Sandstrom E. Two cases of oral to genital HIV-1 transmission. Intl J STD & AIDS 1997; 8:522-525.

Clifford L. HIV seroconversion and oral intercourse. AJPH 1991;81:698.
Edwards SK, White C. HIV seroconversion illness after orogenital contact with successful contact tracing. International Journal of STD & AIDS. 1995; 6:50-51

Keet PM, Albrecht Van Lent IV, Sandfort TG, Coutinho RA, Van Griensven GJ. Orogenital sex and the transmission of HIV among homosexual men. AIDS 1992;6:223-226.

(9 cases in a cohort of 102)

Lifson AR, O’Malley PM, Hessol NA, Buchbinder SP, Cannon L, Rutherford GW. HIV seroconversion in two homosexual mean after receptive oral intercourse with ejaculation. AJPH 1991;80:1509-1510.

Quarto C, Germinario C, Troiano T, Fontana A, Barbuti S. HIV transmission by fellatio (letter). Europ J Epidemiol 1990;9:339-340 (heterosexual female to male oral transmission)

Robinson ED, Evans BGl. Oral sex and HIV transmission. AIDS 1999;16(6):737-8.

Schacker T, Collier AC, Hughes J, Shea T, Corey L. Clinical and epidemiologic features of primary HIV infection. Ann Intern Med 1996;125:256-264.

(4 cases in a cohort of 46 reported only oral risk)

Spitzer P, Weiner NJ. Transmission of HIV infection from a woman to a man by oral sex (letter). N Engl J Med 1989;320:251.

For more information...

CDC National AIDS Hotline: 1-800-342-AIDS Spanish: 1-800-344-SIDA Deaf: 1-800-243-7889

Internet Resources: DHAP: www.cdc.gov/hiv NPIN: www.cdcnpin.org

CDC National Prevention Information Network: P.O. Box 6003 Rockville, Maryland 20849-6003 1-800-458-5231