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

12th World AIDS Conference

Abstracts 43552-43557 955

Results: Answered the call of the Project 944 potential volunteers, 104 (12.5%)
HIV positive. The snow-balling process was the main responsible for the volunteers' arrival, corresponding for 55.7% of the total, with notable increase betwen
the first recruitment semester (11.8%) and the last (80.3%). The prevalence of
HIV positive among the ones that answered also rose from 6.1% to 15.7%.662
volunteers were included in the follow-up. They maintained MSM relationship exclusive or preferential in 88.5%, having balance among steady partners (23.3%),
casual (31.3%) or both (41.4%). In the six months that preceded the reception
interview, 268 (40.5%) of the volunteers referred at least one episode of anal sex
without condom use. In elapsing of the study there were 189 (25.8%) losses of
follow-up. After three years, we have a total of 777.0 person-year. There were
11 serum conversions, with incidence density of 1.42 per 100 person-year. HIV
subtypes have been characterized in 6 of the seroconverters: B (5) and F (1).
Conclusions: The results indicate the need to address the recruitment process, predominantly snow-balling, for groups of higer prevalence of HIV positive.
Eforts should be made in order to decrease the number of lost of follow-up, what
is contradictory with the recruitment in groups of higer prevalence.
Funding: UNAIDS;WHO; Ministry of Health-Brazil; State of Sao Paulo Health
Secretary; FAPESP;CNPQ.
43552 Estimation of vaccine efficacy for prophylactic HIV
vaccines from field trials in developing countries
Ira Longini1'2, D. Kitayaporn3, S. Vanichseni4, K. Choopanya4, M.G. Hudgens2,
M.E. Halloran2, T.D. Mastro3, P.A. Mock3. 1Dept. Biostat., Rollins School Pub.
Health Emory Univ., Atlanta, GA 30322; 2Emory University Atlanta GA, USA;
3HIV/AIDS Collaboration Bangkok; 4 Bangkok Metropolitan Administration
Bangkok, Thailand
Background: Prophylactic HIV vaccines could reduce susceptibility to infection
or disease, i.e., vaccine efficacy for susceptibility (VEs). They also may reduce
infectiousness of vaccinees who become infected, i.e., vaccine efficacy for infectiousness (VE|). This latter effect could produce an important indirect reduction
in HIV transmission even if the vaccine does not protect well against infection.
We propose an augmented design for HIV vaccine trials that allows estimation of
both effects. The augmented design includes steady sexual partners of primary
participants.
Methods: A placebo-controlled phase III HIV vaccine trial is simulated according to the structure of the Bangkok Metropolitan Administration (BMA) cohort of
injecting drug users. In the simulation, 1,250 primary participants are recruited
per arm. Participants and their steady sexual partners are followed every six
months for three years. Primary participants are assumed to be at risk of infection
through needle-sharing at various frequencies. In addition, 50% of the primary
participants have unprotected sexual contact with a steady partner at various
frequencies. A likelihood function based on a Markov model is used to estimate
the VEs and VE1.
Results: In the simulated baseline vaccine trial, cumulative incidence in the
placebo arm among primary participants is 12% for the entire trial. There are
119 total infections in the placebo arm. The secondary attack rate (SAR) among
sexual partners in the placebo arm is 46%. The VEs and VE, were preset to
0.4 and 0.6, respectively. The estimated 95% confidence interval (CI) on VEs is
[0.22, 0.56] and on VE, is [0.37, 0.74]. The power to reject Ho: VEs = 0 and Ho:
VE, = 0 is 1.0 for both. If the HIV incidence rate is reduced so that 92 infections
occur among primary participants in the placebo arm and SAR = 32%, then the
estimated 95% confidence interval on VEs is [0.23, 0.54] and on VE, is [0.31,
0.78]. The power to reject Ho: VEs = 0 and Ho: VE, = 0 is still 1.0 for both.
Conclusions: It should be feasible to estimate both VEs and VE, for vaccine
trials in developing countries that have populations where the primary participants
are exposed to infection through injecting drugs or sexual contact, and who have
steady sexual partners. Several populations, in addition to the BMA cohort, with
this social structure are being considered for HIV vaccine trials.
43554 Role of information system on AIDS prevention in
Pakistan
Mursalin Syed Mohammad. HMIS Advisor, Ministry of Health, PHC Cell Feroze
Center, P.O. Box. 1831, Islamabad, Pakistan
Objective: To collect, transmit, consolidate and process information on 'Suspected AIDS Cases' as part of National HMIS Initiative and incorporate it in
Planning and Management of this health problem.
Project: Since 1992, Ministry of Health, Government of Pakistan have launched
a National Health Management Information System (HMIS) at its (Nearly 1000)
health facilities spread all over the country. To make the effort meaningful and
productive, information collection and processing activities are limited to 18 major
health problems only. 'Suspected AIDS' is considered to be one of the problems
identified. This system is currently operational at 86 districts out of 120 districts
of the country. Here the staff is trained, computer programme (Software) installed
and information has started generating. Contrarily to our belief, HMIS is now
revealing that situation of AIDS' in Pakistan is not as hopeful as was expected.

Based upon the HMIS information, Ministry is now seriously planning to initiate
as country wide health education programme to protect the people from spread
of AIDS in Pakistan.
Results: Till recently the health departments were pursuing "all is well approach" as no definite mechanism/data collection methods existed to know the
gravity of issue. HMIS has raised hopes among the programme managers that a
foundation of efficient management and planning has been laid.

517*/43555 HIV infection in young men in northern Thailand,
1991-1997, increasing role of injection drug use
Kenrad Nelson1, S. Eiutrakul2, D.D. Celentano1, C. Beyrer1, S. Kuntolbutra1,
C. Khamboonruang3. 1Johns Hopkins University, 615 N. Wolfe Street Baltimore,
MD E7132, USA; 2Royal Thai Army Medical Corps, Chiangmai; 3Chiangmai
University, Chiangmai, Thailand
Background: The rates of HIV infection in 21 year old men in northern Thailand
randomly conscripted for military service has been studied since 1991. They are
a good index of the general prevalence of HIV in this population because of their
means of selection; men with histories of drug use, male sex or HIV positivity are
not excluded. We used these data to evaluate temporal trends in risk behavior and
the overall effectiveness of the AIDS prevention program between 1991 and 1997.
Methods: We evaluated HIV prevalence in 7 cohorts (N = 5841) of male conscripts between 1991 and 1997; HIV prevalence was determined by ELISA and
Western blot. Risk behavior was assessed by trained interviewers and association
with HIV prevalence by odds ratios, 95% CI, and logistic regression.
Results: Most men (92.3%-82.1%) were sexually experienced. However, history of sex with a sex worker (CSW) decreased from 81.5% to 46.1% and sex with
CSW in the past year declined from 51.1% to 12.2% between 1991 and 1997.
Condom use with a CSW increased from 61.6% (191) to 92.3% (1997); positive
STD history decreased from 42.2% (1991) to 4.8% (1997). HIV prevalence declined from 11.9% in 1991 to 4.8% in 1996 but then increased to 5.4% in 1997.
History of injection drug use (IDU) increased from 1.1% of men in 1991 to 4.2%
of men in 1997. The odds ratio for HIV prevalence in men with a history of IDU
increased from 1.37 (95% Cl = 0.40, 4.72) in 1991 to 12.3 (95% Cl = 5.56-26.46)
in 1997. Multivariate analysis showed the adjusted O.R. of HIV prevalence for
injecting drug use to increase from 0.79 (0.22-2.27) in 1991 to 13.0 (5.66-29.88)
in 1997 after controlling for sex with a CSW, sex with girlfriends, sex with a male
and STD history.
Conclusion: The public health program to prevent sexually transmitted HIV
from commercial sex has been highly successful and sexual behavior change in
young men has been sustained. However, the decline in HIV prevalence has not
continued due in part to an increased contribution of injecting drug use to the risk
of HIV infection in this population. Effective programs to prevent HIV transmission
in drug users in Northern Thailand are urgently needed.
43556 Now is the time to re-examine partner notification for HIV
exposure
Willi McFarland', B. Adler2, W. Woods1, J. Sabatino2, J. Rinaldi2, T. Lihatsh2,
J.W. Dilley2. 1Center AIDS Prevention Studies Box 0886 San Francisco Ca
94143; 2Univ Cal San Fran AIDS Health Project San Francisco CA, USA
Background: Partner notification is a strategy used in the control of STD with
varying success; benefit of partner notification for HIV is less evident. Utilization
of the San Francisco Department of Public Health (DPH) HIV partner notification
services has been historically low, perhaps due to a lack of trust in the DPH's
ability to maintain confidentiality. New treatments for early infection, tests that
determine the duration of infection, and changes in sexual and testing behaviors may make partner notification more beneficial. An intervention study among
anonymous testers presented an opportunity to assess current willingness to
inform partners of HIV exposure.
Methods: MSM (N = 73) were recruited for a counseling intervention study
when scheduling an anonymous HIV antibody test. Participants were non-IDU,
had at least one previous test, were HIV negative at their prior test, and had
unprotected anal intercourse with another male who was positive or of unknown
status within the last year. Subjects were asked whether they were willing to notify
partners of exposure, either personally and through DPH services.
Results: When asked if they would inform their sex partners, were they to
test positive, 66 (90%) responded "yes", 5 (7%) were "not sure", and 2 (3%)
responded "no". When asked if they were willing to have the DPH notify partners,
29 (40%) responded "yes", 7 (10%) were "not sure", and 36 (50%) responded
"no". Of the 5 who were "not sure" they would inform their partners themselves,
2 (40%) were willing to have the DPH notify their partners. Men willing to have
the DPH contact partners did not differ from other subjects in the number of sex
partners in the last year, history of STD, race, age, education, or income.
Although 90% of the participants said that they would inform their partners
themselves if testing HIV-positive, a surprising number also indicated their willingness to have the DPH notify partners. Given this response along with new
developments in testing and treatment, the time is ripe to evaluate a more proactive partner notification system for HIV exposure. Careful attention must be
paid to laws and mechanisms that preserve confidentiality.
|43557 Public health databases: A client's right to choose
Jan Gurley1, Teri Dowling2, G.D. Levinson3, M.L. Katz2, R.J. Gurley2. 1San
Francisco DPH, 25 Van Ness Ave., #500 San Francisco, CA 94102-6033; 2San
Francisco Dept. of Public Health San Francisco CA; 3Support Center for

Non-Profit Management San Francisco CA, USA
Issues: Public and non-profit organizations are increasingly involved in the development of databases which contain information about people living with HIV,
including management systems for reporting and tracking services. Little work has
been done to describe or explore the involvement of clients in the development
of these systems and the ways in which clients do or do not have choices about
the contents or use of information.