What is the risk of acquiring HIV from oral sex? Workshop Ground Rules Confidentiality Use “I” statements Pass if you want Agree to Disagree Leave PC at the Door Speak one at a time Step up/Step back Turn off cell phones and pagers

Ice Breaker INTRODUCTORY QUESTIONS: Name? Where are you from? Occupation? How would you counsel someone on the risk of acquiring HIV through performing fellatio?

Evidence Case reports – total of 28 (some with multiple cases) –Majority are fellatio (male to male receptive oral sex) –The number of case reports is actually low when one considers the size and duration of the pandemic Animal studies –SIV can be transmitted through oral or tonsillar mucosa Breastfeeding Epidemiological studies consistently show very low risk

Genetics, biological history Oral Health Co-morbidity Drug use Sexual behaviors Partner infectivity factors Trauma Sores Inflammation Allergy STI-Coinfection Ejaculation Immunosupression Xerostomia Hypothesized Co-Factors

Demographics of male participants (N=363) Median age (IQR) 40 (32-49) Gay or bisexual 100% Race/ethnicity Asian 10% White 72% Latino 8% African American 5% Median no. of previous HIV tests (IQR) 5 (3-10) Median no. of males performed fellatio on last 6 months (IQR) 3 (2-6)

Detels et al., Seroconversion, sexual activity, and condom use; JAIDS 1989: Only one seroconversion among 232 in 2915 MSM followed for 9330 PY (interval in which ano-genital sex was reported was outside of the range of the induction period between exposure and 1 st anti-HIV positive test) * Estimated incidence: total no. of men seroconverting in each category divided by the sum of the men in that category for each of the four visit intervals since baseline

Men w/ HIV-infected partner Women with HIV infected partner Total individuals with HIV-infected partner No. of individual who had unprotected sex Fellatio Without ejaculation With ejaculation Cunnilingus Estimated No. of unprotected orogenital contacts 1,69517,62119,316 Fellatio Without ejaculation With ejaculation Cunnilingus 1, ,965 5,905 3,060 8,656 10,046 6,545 3,501 9,270 Person-years at risk HIV seroconversions000 Del Romero et al., Evaluating the risk of HIV transmission throught unprotected orogenital sex; AIDS 2002: over unprotected orogenital contacts with their HIV-infected partner, without a single case of seroconversion to HIV occurring.

Page-Shafer et al., Sexual risk behavior and risk factors for HIV-1 seroconversion in homosexual men participating in the Tricontinental Seroconverter Study, AJE 1997 Case-control study of 345 seroconverters (cases) compared to 345 HIV negative controls found low but significant risk of HIV in association with oral sex Type of contactOdds Ratio (per partner increase) 95% CI Receptive anal sex Receptive oral sex STD (yes vs. no) Amphetamine user (yes vs. no)

Vittinghoff et al., Per-contact risk of HIV transmission between male sexual partners; AJE Risk of acquiring HIV infection from receptive oral sex with HIV+/?* serostatus partners was 0.04 % (1/2500 acts) in a prospective cohort study of 2189 high risk homosexual and bisexual men. Type of contactper contact risk (%)95% CI Unprotected receptive anal sex with HIV+/? partner Protected receptive anal sex with HIV+/? Partner Unprotected insertive anal sex with HIV+/? partner Unprotected receptive oral sex with HIV+/? partner *HIV+/?: HIV positive or unknown serostatus partner

Page-Shafer 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 No incident or prevalent HIV infections detected in participants who report oral sex as their only sexual behavior Among 239 MSM who practiced exclusively fellatio in the past 6 months: 50% had 3 partners, 98% unprotected; 28% had an HIV-positive partner. No HIV was detected (probability of orally acquired HIV = 0 (95% CI: 0, 1.5). To-date data (unpublished): 0 infections in 363 participants (p=0; 95% CI: 0, 1.0)

Oral sex rarely transmits HIV Exposure is frequent Reported cases are few Measured risk is low Calculated risk is very low

Oral sex rarely transmits HIV Macaque model requires high SIV concentrations > intravenous Baba TW, et al. Science 1996: 272: No SIV in GI tract, nor dendritic cells Stahl-Hennig C, et al. Science 1999: 285:

Biology prevents oral transmission Saliva inhibits HIV replication –Mucosal antibodies, mucins, thrombospondin, secretory leucocyte protease inhibitor, hypotonicity Target cells limited to tonsillar tissue Duration of exposure is brief

In contrast: HIV prevalence and incidence among repeat HIV testers in San Francisco from December 1999 to February 2001 Sexual behavior HIV Prevalence % (95% CI) HIV Incidence % (95% CI) Overall, HIV Infection among repeat testers 3.3 (2.9–3.9)1.9/100 (1.6–2.3) Persons reporting unprotected RAI 5.1 (4.1–6.3)3.5/100 (2.7–4.5) Person reporting protected RAI 2.3 (1.7–3.1)1.7/100 (1.2–2.3)

Group Challenge Create a message for the public about HIV and Oral Sex: Groups 1 & 2: A Billboard ad Groups 3 & 4: An HIV Counseling and testing session Groups 5 & 6: A TV ad or PSA Groups 7 & 8: A newspaper Ad Groups 9 & 10: A Brochure