Reports on HIV/AIDS: 1990

NOVEMBER 30, 1990, MMWR, Vol. 39, RR-16 ([inclusive page numbers]
4. Longini and Clark, in collaboration with staff at the Walter Reed Army Institute
of Research, have developed a staged model for the decline in CD4+ cell counts
in persons with HIV infection. In general, the results agree with the U.S. Army
data summarized in this section. This partially fulfills recommendation 5.
AIDS CASE PROJECTIONS
AIDS case projections are based on the incidence of AIDS, adjusted for estimated
reporting delays. The charge to the workshop group was to review methods for
forecasting future AIDS cases and to recommend how AIDS case projections should
be made. The 1986 and 1988 projections (1,2) were obtained by extrapolating recent
trends in the incidence of AIDS. Recent changes in these trends, shown in Figures 1-3,
indicate the need to reconsider the earlier projections. Interpretation of the change in
trends of AIDS incidence is an important factor in the choice of a model for projecting
AIDS cases and in the ultimate projected ranges.
Workshop participants concluded that the number of AIDS cases diagnosed in the
United States will continue to increase through 1993 (Table 2). An estimated 41,500
cases diagnosed during 1989 eventually will be reported-a 19% increase over the
corresponding count for 1988, greater than the earlier report of a 14% increase for a
similar period based on less complete data (10). After adjustments for underreporting, it is estimated that 52,000-57,000 cases of AIDS will be diagnosed during 1990
and that this figure will rise to 61,000-98,000 cases diagnosed during 1993 (Table 2).
The group also concluded that the number of AIDS cases diagnosed in the United
States will continue to increase through 1993 for each of the current principal
transmission categories (homosexual and bisexual men, IVDUs, persons infected
TABLE 2. Projected numbers* of acquired immunodeficiency syndrome (AIDS) cases,
deaths, and living persons with AIDS, United States, January 1989-December 1993
AIDS cases
Year New casest Alive Deaths
1989 44,000-50,000 92,000-98,000 31,000-34,000
1990 52,000-57,000 111,0001-122,000 37,000-42,000
1991 56,000-71,000 127,000-153,000 43,000-52,000
1992 58,000-85,000 139,000-188,000 49,000-64,000
1993 61,000-98,000 151,000-225,000 53,000-76,000
Cumulative total
through 1993" 390,000-480,000 - 285,000-340,000
*Projections 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.
tNumber of cases diagnosed in that year.
'This number differs from the number (101,000) published in the MMWR (1990;39:110-2,117-9)
because of a transcription error.
"Rounded to the nearest 5,000. Includes an estimated 120,000 AIDS cases diagnosed through
1988, 48,000 persons alive with AIDS at the end of 1988, and 72,000 deaths among patients
diagnosed as having AIDS through 1988.

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