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

12th World AIDS Conference

Abstracts 13217-13220 129

Methods: Remnant serum specimens collected for routine purposes from the
first visits of all patients during an annual study period in 4 STD clinics in Baltimore,
New Orleans, and Houston were tested for HIV-1.
HIV-1 positive specimens from 1991-96 were then tested using a less sensitive modification of the HIV-1 EIA (3A11, Abbott), which detects HIV 0.35 years
(95% CI: 0.30-0.41 years) after detection by the standard EIA. The annualized
incidence was estimated by [number HIV-1 positive but negative on the modified
3A11]/[(total number tested minus number positive on modified 3A11) x 0.35
years].
Results: Overall, 734/22,432 (3.3%) patients in these 4 STD clinics were HIV-1
positive; 77/734 (10%) were non-reactive on the less sensitive assay. Of these
77 incident cases, 12 (16%) were MSM and 25 (32%) were women. Incidence
among MSM was 14 percent per year (ppy) (95% Cl: 5-30 ppy) and ranged by
clinic from 5-20 ppy. Among heterosexual men, incidence was 0.8 ppy (95% CI:
0.48-1.4 ppy); among women, it was 0.9 ppy (95% CI: 0.45-1.6 ppy).
Conclusions: HIV seroincidence among MSM was approximately 17 times
higher than that among heterosexuals in this population, indicating that substantial HIV transmission continues among MSM. These findings are consistent with
record-based studies in the same clinics, suggesting that this simple, inexpensive
serologic testing strategy may have wide applicability for estimating incidence in
populations at high risk for HIV infection.
13217 Evidence for evolution of HIV-1 within behavioral risk
groups in San Francisco 1984-1997
Edwin D. Charlebois1, D. Osmond2, R. Grant2, A. Moss2, W. Winkelstein3.
1UCSF-CAPS, Suite 600, 74 New Montgomery, San Francisco; 2University of
California San Francisco, CA, 3University of Califonia Berkeley, CA, USA
Objectives: To compare HIV-1 genetic diversity in San Francisco seroconverters
to investigate the evidence for segregation of viral strains by behavioral risk group
and to look for evidence for evolutionary change overtime.
Methods: HIV-1 RNA was extracted from stored or fresh plasma taken within
6 months from the time of seroconversion. Virus was successfully isolated from 9
gay men from the San Francisco Men's Health Study, who seroconverted during
1984-1985, eight gay men from the San Francisco Young Men's Health Study
- seroconverting during 1994-95, and 9 heterosexual injection drug users from
a study of HIV and TB in the San Francisco homeless seroconverting recently.
Sequencing was performed using an ABI automated sequencer. DNA distances
were calculated using a Kimura 2-parameter model within the DNAdist program
contained within the PHYLIP 3.0 package for UNIX.
Results: All isolates were found to cluster with the Clade B consensus sequence. Neighbor joining trees and maximum-parsimony methods placed the
heterosexual isolates in among the samples from gay men taken in the 80's and
90's. A significant difference in the mean genetic distance between the three
groups was observed (p -.0001 Wilcoxon test)
Conclusion: Unlike the situation in Amsterdam, isolates from injection drug
users did not uniformly cluster apart from isolates from gay men. Genetic diversity
was relatively low in isolates from gay men at the start of the San Francisco
HIV epidemic. Higher genetic diversity was seen in samples from gay men more
recently infected with HIV, consistent with evolutionary divergence. Heterosexual injection drug users were found to have an intermediate level of diversity,
suggesting a later introduction of HIV into this population.
13218 Declining AIDS mortality in New York City (NYC)
Mary Ann Chiasson, W. Li, L. Berenson, S. Schwartz, T. Singh, S. Forlenza. New
York City Dept. of Health New York, 125 Worth Street Box 6 New York, NY, USA
Objective: To compare AIDS mortality in New York City for the 2nd half of 1995
and the 2nd half of 1997 by gender, race/ethnicity, and age.
Design: Descriptive analysis.
Methods: The analysis includes all NYC death certificates filed with NYCDOH
by 1/12/98. Data for 1997 are provisional with only small changes expected.
ICD-9 codes 042-044 identified AIDS deaths. AIDS case surveillance data were
used to determine living AIDS cases and for estimates of mortality by HIV risk
behavior for 1995 and 1996.
Results: AIDS deaths plateaued at -7,000 in 1995, dropped 29% to -5,000
in 1996 and an additional 48% to ~-2,600 in 1997. During the same time, the
number of people living with AIDS increased from 31,913 to 36,198. From the 2nd
half of 1995 to the 2nd half of 1997, there was a 71% (2,644 to 767) decline in
male and a 63% (930 to 341) decline in female deaths. Deaths fell for both men
(M) and women (W) by race/ethnicity: whites 78%M & 73%W; blacks 65%M &
59%W: Hispanics 72%M & 66%W. Deaths also declined in all age groups: 87%
in 0-14 yrs; 64% in 15-24 yrs; 76% in 25-34 yrs; 71% in 35-44 yrs; and 61% in
45+ yrs. By HIV transmission category, deaths fell -40% in men who have sex
with men and -30% in injecting drug users and heterosexuals from 1995 to 1996.
Conclusion: The dramatic decline in AIDS deaths first observed in NYC in 1996
continued through 1997 at slightly varying rates in all demographic groups. This
occurred at a time when new antiretroviral therapies became widely available.

13219 AIDS surveillance trends in the United States: Declines in
AIDS diagnoses and deaths direct a shift to integrated
HIV/AIDS case surveillance
Patricia L. Fleming, P.A. Sweeney, R.L. Frey, M.A. Mays, J.W. Ward. CDC 1600
Clifton Rd, NE, Mailstop E-47, Atlanta, Georgia, USA
Objective: To describe recent declines in US AIDS diagnoses (dx) and deaths
and examine trends in HIV dx compared to AIDS in 26 states that conduct HIV
case reporting.
Methods: AIDS data from all States and Territories (data reported to CDC
through Dec '97 were adjusted for reporting.
Methods: AIDS data delays and unreported risk) and HIV surveillance data
from 26 HIV reporting states were examined by half-year of dx or death through
June '97. Based on their earliest HIV dx date, persons first reported as HIV
infected were compared to persons reported with AIDS.
Results: Through Dec '97, 641,086 AIDS and 92,107 HIV (not AIDS) cases
were reported to CDC. AIDS trends: Declines in AIDS and deaths from the first
half of 1995 to the first half of 1996 were 9% and 14%, respectively. Comparing
the first half of 1996 to the first half of 1997: AIDS declined 12% to 29,520 during
Jan-June '97; deaths declined 44% to 12,040. Declines in AIDS and deaths were
greatest for homsexual/bisexual men: AIDS declined 17% to 12,170 and deaths
declined 51% to 4,840. For injecting drug users, declines in AIDS and deaths
were 11% and 28%, to 8,830 and 4,060, respectively. For heterosexual-contacts,
AIDS incidence was stable (N = 6400) and deaths declined 33% to 2,010. AIDS
prevalence was 259,000 persons in June '97; a 13% increase from June '96.
HIV trends: During 1994, 1995 and 1996, trends in persons with HIV dx (not
AIDS) were stable: 9,800, 10,190, and 10,180, respectively. During 1994 through
1996, each year approximately two-thirds of persons with HIV/AIDS were first
diagnosed with HIV.
Conclusions: Declines in AIDS incidence and deaths in the US principally
reflect the impact of treatment-induced delays in progression from HIV to AIDS
and increased survival after an AIDS diagnosis. The number of new HIV dx is not
affected by treatment. Because two-thirds of persons diagnosed each year were
diagnosed with HIV before they progressed to AIDS, integrated HIV/AIDS surveillance is more representative of all persons diagnosed with HIV and provides
opportunities for early prevention and treatment interventions.
13220 Surveillance of AIDS in Canada - Change to surveillance
of HIV infections
John Farley, D.W. Sutherland, P. Yan, J. Sutherland. Brooke Claxton Bldg level
01 p10900B1 Tunneys Pasture, Bureau of HIV-AIDS and STDs Health Canada,
Ottawa, Ontario, Canada
Background: AIDS cases reported to the National AIDS Case Surveillance System (ACRSS, LCDC) show a shift from predominantly men who have sex with
men, to multiple HIV epidemics in different sub-populations occurring at different
rates in different jurisdictions. It is no longer valid to predict the time to onset of
AIDS from HIV infection. AIDS case reporting alone is now less appropriate for
surveillance for HIV infections.
Methods: Since 1983 AIDS surveillance has been the principal mechanism
for monitoring the AIDS epidemic. Demographic, epidemiologic, and risk factor
information are reported confidentially (personal identifiers removed) to LCDC.
Through statistical methods adjustments are made for the delays and the AIDS
data are used to estimate HIV incidence.
Results: As of October 23, 1997, there had been a cumulative total of 15,310
cases of AIDS reported to LCDC since the beginning of the AIDS epidemic. Males
account for 93.6%, and females 6.4% of the cumulative reported AIDS cases. It
is estimated that there have been approximately 20,000 cases since the onset
of the AIDS epidemic. The reported AIDS incidence appears to have levelled
off around 1993-1995, and started declining by about late 1995. Men who have
sex with men continues to be the predominant risk category affected. Recent
trends are however showing increases in the heterosexual, women, intravenous
drug use and aboriginal categories. Variations in trends are also apparent within
specific birth cohorts in these sub-populations. More data will be presented on the
changing Canadian AIDS/HIV However, even after adjusting for reporting delays,
an annual decline of about 20% has been noted in the reported AIDS cases
between 1995, and 1996. The decline has continued into 1997. This may reflect
decreased reporting and/or an actual decline in AIDS cases.
Conclusion: The decline in reported AIDS cases may be attributed to newer
and improved treatment and prophylaxis regimens delaying the onset of AIDS.
Recent estimates as well as available data on HIV prevalence and incidence
also indicate increasing HIV incidence and prevalence. To better monitor the
burden of HIV disease, and for more relevant program planning, a system for HIV
surveillance is recommended. Proposed strategies will be discussed.
|13221 The National Perinatal HIV Surveillance Program: Canada
1985-1996

Susan King1, N. Lapointe2, J. Forbes3, U.D. Allen', S.E. Read1, J. Singer4.
1University of Toronto, Toronto, ON; 2Universite de Montreal, Montreal, QC;
3University of Birtish Columbia, Vancouver, BC; 4CTN of British Columbia,
Vancouver, BC, The Canadian Pediatric AIDS Research Group (CPARG),
Canada
Objectives: To document all pregnancies in Canada of women known to be HIV+