Reports on HIV/AIDS: 1990

NOVEMBER 30, 1990, MMWR, Vol. 39, RR-16 [inclusive page numbers]
2. Projections should be made by stage of disease for the number of living patients
with HIV-associated health problems, with stage based on a clinical indicator
such as CD4+ cell count.
3. Statistical methods used to project the future course of the epidemic should
continue to be based on surveillance data. To improve projections, more data
should be obtained on the completeness and timeliness of AIDS case reporting.
More data are also needed on the incidence of HIV, the spectrum and natural
history of HIV infection, the prevalence of types of behavior associated with HIV
acquisition and transmission, and the effect and use of various types of therapy.
These data should be obtained for both children and adults and for the major
HIV-transmission categories.
4. Statistical methods should be developed for making more accurate AIDS case
projections. These methods should incorporate empirical data on HIV incidence,
effects of therapy, and changes in the incubation period.
Actions taken since meeting
1. Brookmeyer and Liao (24) have extended their back-calculation procedure to
incorporate empirical estimates of recent HIV incidence. This fulfills recommendation 4 and is related to recommendation 2.
2. Longini and W.Y. Tan (Memphis State University) extended a model for the
stages of HIV infection (25) to include effects of therapy. Longini, R. Byers
(CDC), and Tan incorporated this extension into back-calculation (26). This work
is related to recommendations 2 and 4.
3. CDC, in collaboration with selected health departments, is now conducting
special surveillance projects to describe the spectrum of HIV-associated health
problems among adults and children, the completeness of AIDS case and death
reporting, and the extent of HIV-related morbidity and mortality not included in
AIDS surveillance criteria. In addition, another project is being initiated to collect
TABLE 4. Comparison between current and 1988 projected numbers of acquired
immunodeficiency syndrome (AIDS) cases diagnosed by year, United States, 1988 -1992*
1988 Adjusted 1988 Current
Year projections projections* projectionst Percent change'
1988 39,000 42,000 41,0001 -
1989 49,000 52,000 44,000 -50,000 -10
1990 60,000 64,000 52,000-57,000 -15
1991 71,000 76,000 56,000 -71,000 -16
1992 80,000 86,000 58,000-85,000 -17
*Published projections increased by 7% to account for change in multiplier used to obtain all
diagnosed cases, from 1.10 used in 1988 to 1.18 used in 1989.
tProjections are adjusted for unreported diagnoses of AIDS by adding 18% to projections
obtained from reported cases (corresponding to 85% of all diagnosed cases being reported:
1/0.85 = 1.18) and rounded to the nearest 1,000.
PPercent change of the midpoint of the current projection range versus the adjusted 1988
projection.
'Current estimate of 35,000 cases diagnosed in 1988 that will be reported (cases reported
through September 1990, adjusted for reporting delays), increased by 18% to account for
underreporting.

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