Document 2321
 DOCN  M94A2321
 TI    Reconstruction and prediction of HIV/AIDS in Europe.
 DT    9412
 AU    Downs AM; Heisterkamp SH; Ancelle-Park RA; Brunet JB; European Centre
       for the Epidemiological Monitoring of AIDS,; St-Maurice, France.
 SO    Int Conf AIDS. 1994 Aug 7-12;10(1):330 (abstract no. PC0254). Unique
       Identifier : AIDSLINE ICA10/94370254
 AB    OBJECTIVES: To reconstruct the HIV epidemic in Europe from AIDS
       incidence data reported through the surveillance system and to provide
       forecasts of AIDS incidence and stage-specific HIV prevalence. METHODS:
       AIDS incidence reported by 30 September 1993 was adjusted for reporting
       delays. A back-calculation method was implemented with: 1) the HIV
       infection curve modelled as a yearly step function with smoothness
       constraints; 2) progression to AIDS modelled as a 7-stage Markov
       process; 3) stage-specific effects of prophylactic treatment modelled
       from 1988 onwards; 4) estimation by an empirical Bayes method, with the
       prior distribution of the HIV incidence steps provided by the smoothness
       constraints of a penalized likelihood method. The performance of the
       estimation procedure was investigated using simulated data reflecting
       various possible forms of the HIV incidence curve. HIV incidence and
       stage-specific prevalence to mid-1993 were estimated by transmission
       group for three groups of countries: the European Union (EU); low
       incidence (LI) countries (< 50 AIDS cases/million population), mostly in
       eastern Europe; other countries of the WHO European region. RESULTS: Our
       estimation method performed well for most simulated epidemics. For the
       EU, total HIV/AIDS prevalence among adults was estimated to be around
       310000 at end 1989 and 440000 at mid-1993. The latter estimate is more
       uncertain than the former due to large variances in the estimates of
       recent HIV incidence. Group-specific estimates (1989, 1993) were:
       homo/bisexual: 95000, 98000; IDU: 120000, 180000; heterosexual: 50000,
       81000; other/undetermined: 46000, 87000 (includes persons possibly
       infected heterosexually). Since 1987, prevalence appears to have
       stabilized among homo/bisexual men and, at least until 1990, among IDUs;
       estimated recent increases in the latter group carry wide confidence
       intervals. In the LI countries, prevalence is estimated to have
       increased steadily, both overall (5200 in 1987, 7300 in 1989, 11000 in
       1993) and in each of the above 4 groups, with the largest % increase in
       the heterosexual transmission group. CONCLUSION: AIDS incidence is
       predicted to decrease slowly among homo/bisexual men in the EU. In other
       EU groups and in all 4 LI groups, incidence is expected to continue to
       increase through the late 1990s.
 DE    Acquired Immunodeficiency Syndrome/*EPIDEMIOLOGY/TRANSMISSION  Computer
       Simulation  *Disease Outbreaks  Europe/EPIDEMIOLOGY  Female  Human  HIV
       Infections/*EPIDEMIOLOGY/TRANSMISSION  HIV Seroprevalence/*TRENDS  Male
       Models, Statistical  *Population Surveillance  Risk Factors  Sex
       Behavior  Substance Abuse, Intravenous/COMPLICATIONS/EPIDEMIOLOGY
       MEETING ABSTRACT

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).