Bridging the Gap: Conference Record [Abstract book, International Conference on AIDS (12th: 1998: Geneva, Switzerland)]

364 Abstracts 23115-23118

12th World AIDS Conference

[OR] = 1.8, 95% Cl = 1.1, 3.1 for each comparison). Among HPV positive men
at entry, detection of additional HPV types was more common among HIV+ men
(OR = 2.3, 95% CI = 1.5, 3.4). Becoming HPV negative during follow-up was less
common among men with HIV (OR = 0.4, 95% CI = 0.3, 0.6) or high entry HPV
levels (OR = 0.6, 95% Cl = 0.4, 0.9). Among HIV+ men, HPV persistence was
associated with presence of HIV DNA in the anal canal (OR = 2.8, 95% CI = 1.3,
6.1), but not with CD4 count.
Conclusions: Risk of incident and prevalent anal HPV infection appears to
increase with sexual exposure, epithelial trauma, HIV infection and immune deficiency. Incident infection may result from recent sexual exposure or reactivation
of latent infection. Further studies are needed to elucidate the mechanism by
which HIV DNA in the anal canal increases risk of HPV persistence.
23115 Increasing risk behavior has not led to higher HIV
incidence rates in the San Francisco Young Mens' Health
Study: 1993-1998
Dennis Osmond1 2, E. Charlebois2, K. Page-Shafer2, R. Stall2, H. Sheppard3.
'Box 1347 Dept. of Epidemiology Univ of Califirnia San Francisco San
Francisco; 2 UCSF Center for AIDS Prevention Studies San Francisco CA; 3Calif.
Dept. of Health Services San Francisco CA, USA
Objective: To determine rates of HIV incidence and risk behavior over time in a
population-based prospective study of young homosexual/bisexual men living in
San Francisco, California.
Methods: A cohort of 428 young homosexual men were recruited by a probability household sample of single men ages 18-29 in 1992-93. An additional
sample of 622 of their friends were recruited by referral during the first cycle
of follow-up. Four follow-up examination cycles have been completed and the
fifth is in progress. HIV incidence rates with 95% confidence intervals (CI) were
calculated for each annual cycle. Percent of men HIV negative at the beginning of each cycle reporting unprotected receptive anal intercourse (URAI) was
calculated (excluding behavior with an HIV seroconcordant primary partner).
Results: 32 men have seroconverted (SC) during follow-up. The percent of
HIV negatives reporting URAI in increased in 1995-1997 by 50% over 1993-1995
while HIV incidence was steady. The increase in risk behavior not explained by
low risk persons dropping out of the study.
Year % URAI SC/N Rate/yr (95% CI)
1993-94 14.0% 5/260 2.6% (0.9-5.6)
1994-95 13.6% 7/660 1.4% (0.6-2.6)
1995-96 18.7% 10/545 1.3% (0.6-2.3)
1996-97 22.5% 7/481 1.3% (0.6-2.5)
1997-98 TBD 3/431 0.9% (0.2-2.2)
Conclusions: Increasing risk behavior in young men is a disturbing trend that
challenges prevention strategies but has not yet led to increasing HIV infection
rates. The reasons for this seeming paradox are not known but may be related to partner selection, declining HIV seroprevalence, and possibly decreased
infectiousness of HIV positives as a result of antiretroviral therapy.
23116 Increasing rates of unprotected anal intercourse among
San Francisco gay men include high UAI rates with a
partner of unknown or different serostatus
Maria Ekstrand, R. Stall, J. Paul, D. Osmond, T. Coates. UCSF Center for AIDS
Prevention Studies S-600 74 New Montgomery SF 94105, USA
Objectives: 1) To examine the prevalence and individual patterns of sexual risk
taking in a prospective longitudinal cohort of San Francisco gay men; 2) to measure the prevalence and correlates of unprotected anal intercourse (UAI) with
partners of unknown of different serostatus in 1996.
Methods: San Francisco gay men between 18-29 years were recruited using
household sampling (n = 408) and participant referrals (n = 622) and followed
annually. Behavioral and psychosocial measures were administered using a self-administered survey. In 1996, participants were asked whether any UAI had
occurred with a partner of different or unknown serostatus.
Results: Cross-sectional rates of UAI have increased significantly during the
4-year study period:
1993 1994 1995 1996
Receptive UAS 31% 31% 37% 41%*
Insertive UAS 25% 28% 35% 39%
All UAS 37% 37% 45% 50%/
significantly (p <.05) greater than in previous wave
An examination of individual behavior patterns shows that 51% of participants
practiced unprotected anal sex occasionally (i.e. in 1, 2, or 3 years). In 1996,
we examined in detail the conditions under which UAI occurred. 22% of the

participants indicated that they had engaged in UAI with a partner of different or
unknown serostatus, Compared to all other men, participants who reported UAI
with a partner of an unknown or different serostatus also reported having more
male sexual partners, more sex in bathhouses and sexclubs, more sex under the
influence of alcohol, and were more likely to perceive UAI as "inevitable".
Conclusions: The increasing rates of unprotected anal sex in this population
can not be attributed solely to negotiated safety since about half of the men

reporting UAI stated that this occurred with partners of unknown or different
serostatus. This figure is especially alarming in light of the high rates of HIV
prevalence among San Francisco gay men. Intervention programs targeting this
population are urgently needed to avoid ongoing waves of new HIV infections in
San Francisco.
123117 1 Patterns of oral sex among men who have affective and
sexual relations with other men (MASM) in Montreal
Robert S. Meris12, A. Dufour3, M. Alary4, J. Otis5, B. Masse4, B. Turmel6,
R. LeClerc7. 'Dept. Public Health Sciences, University of Toronto, 12 Queen's
Park Cres W, Toronto, Ontario M5S 1A8; 2Dept. Public Health Sciences U. of
Toronto, Toronto, ON; 3Hospital Saint Sacrament, Quebec, PQ; 4 Universite
Laval, Quebec, PQ; 5Dept. of Sexology, UQAM, Montreal, PQ; 6Montreal Public
Health Department; 7COCO-Sida, Montreal, PQ, Canada
Objectives: (1) To characterize patterns of oral sex among Montreal MASM and
(2) to determine the degree and determinants of unprotected receptive oral sex
with an HIV-positive partner.
Design: Cohort study with follow-up visits every 6 months.
Methods: At the Omega cohort study, we are recruiting HIV-negative MASM to
determine the incidence and psychosocial determinants of HIV infection. At each
visit, we test for HIV and administer a questionnaire including detailed questions
about sexual practices. We examined patterns of oral sex in the previous 6
months among subjects presenting for their second visit (April-October 1997).
Results: Of the 431 MASM presenting for their second visit, 400 had had sex
with a regular or casual sexual partner. The proportions who reported unprotected
receptive oral sex with a regular partner according to the partner's HIV serostatus
were: seronegative 93.9% (n = 196), unknown 90.9% (n = 186) and seropositive
87.5% (n = 32). For casual partners, the findings were: all partners 92.0% (n =
299), and seropositive 72.7% (n = 32). In a multivariate logistic model comparing
MASM who had had unprotected oral sex with a seropositive partner (n = 36) with
those who had not had risky anal sex or oral sex with a seropositive partner (n
= 273), the following variables were found to be significantly associated: having
had a cohabiting partner who had died, odds ratio (OR) = 72.4; consumed drugs
or alcohol during sex, OR = 8.2; fewer regular sexual partners in the previous 6
months, OR = 5.1; having children, OR = 3.1; and less likely to perceive a risk of
HIV infection from receptive (OR = 0.73) and insertive (OR = 0.56) oral sex.
Conclusions: Most MASM in Montreal engage in oral sex. A small but substantial proportion have unprotected oral sex with a known HIV-positive partner;
this was associated with several demographic and behavioural factors and a
lower perceived risk associated with oral sex. Though the HIV risk associated
with oral sex may be small, case reports and epidemiologic studies suggest that
transmission can occur and may account for an increasing proportion among the
(much reduced) new HIV infections among MASM.
123118 Evidence of elevated HIV incidence and relapse to unsafe
sex among young men having sex with men (MSM) in
Vancouver, Canada
Martin Schechter, Steffanie Anne Strathdee, S.L. Martindale, M.L. Miller,
R.S. Hogg, B. Woodfall, P. Sestak, M.T. Schechter. B.C. Centre for Excellence in
HIV/AIDS, Vancouver BC, Canada
Objective: To determine HIV incidence among young MSM and investigate trends
in unsafe sex behaviours.
Methodology: Beginning May/95, MSM aged 18-30 who had not previously
tested HIV+ were enrolled in a prospective study in Vancouver, Canada. At baseline and annually, men completed a questionnaire on sociodemographics and
sexual risk behaviours and had an HIV test. Behaviours pertained to the year
prior to baseline, and baseline to first follow-up (mean: 15 mo.). HIV incidence
density was calculated. Among men remaining HIV negative, we compared baseline and follow-up responses for unprotected anal insertive or receptive sex with
regular (>1 contact per mo.) and casual (<1 contact per mo.) male partners.
Among men reporting always using condoms during anal sex prior to baseline,
we defined 'relapse' as any unprotected anal sex reported at follow-up. Odds
ratios (ORs) for relapse were tested using McNemar's test.
Results: Of 386 men at follow-up, HIV incidence was 1.96 per 100 pyrs (95%
Cl: 0.74, 3.18). Of 10 seroconverters, 4 reported sex trade and 3 injected drugs
(including one sex worker.). Three reported having unprotected anal sex with a
male they knew was HIV+. Among HIV negative men with regular partners (n =
266), odds of relapse were elevated for unprotected insertive (OR = 2.4; 95%
CI: 1.5-4.4.) and receptive anal sex (OR = 2.1; 95% CI: 1.3-3.3). Among HIV
negative men with casual partners (n = 261), similar elevations were observed
for unprotected insertive (OR = 1.8; 95% CI: 1.1-3.0) but not receptive anal sex
(OR = 1.2; 95% CI: 0.7-2.2). The true extent of incidence and relapse may be
under-estimated, since men who were eligible for follow-up but who had not yet
returned were younger (p < 0.001), had less education (p < 0.001), were more
likely to be unemployed (p < 0.001), non-white (p = 0.004), and were more likely
to engage in the sex trade (p < 0.001), than men who returned for follow-up (80%

return rate).
Conclusions: We observed elevated HIV incidence among young MSM in
Vancouver. MSM who inject drugs, engage in the sex trade, or who knowingly
take risks with HIV+ partners, may be at highest risk. Our analysis is limited by low
power, self-reported data, and differential follow-up. However, early indications
of a relapse to unsafe sex are consistent with early incidence data. Our findings
underscore the urgent need for targeted HIV interventions for young MSM, par