Reports on HIV/AIDS: 1990

NOVEMBER 30, 1990, MMWR, Vol. 39, RR-16 [inclusive page numbers]
through heterosexual transmission, and children infected perinatally; see Table 3).
These projections include an adjustment for the estimate that approximately 85% of
diagnosed AIDS cases (i.e., 85% of all persons with diagnosed diseases meeting the
current surveillance criteria for AIDS) are eventually reported.
The current projections are lower than those made in 1988 (the midpoint of the
current projected range is 10% lower for 1989 and 17% lower for 1992; see Table 4),
reflecting the change in the trend in the incidence of AIDS that occurred in 1987. A
discussion of possible reasons for the change in the rate of increase did not yield firm
conclusions, but the group thought that the change was too abrupt to have been
caused solely by past changes in HIV incidence.
The current range of projections was derived from extrapolation and from
back-calculation, with two of the back-calculation models incorporating plausible
estimates of the effect of currently available medical therapy and of the proportions
of infected persons receiving therapy (see Appendices A and B). Predictions after
1990 arq especially uncertain, however, because little information exists on the future
extent and duration of the therapeutic effect of zidovudine, prophylactic therapy for
Pneumocystis carinii pneumonia, or other treatments in delaying AIDS, or when
these treatments began to be used extensively, and the number of persons receiving
such treatments.
Recommendations
1. AIDS case projections should continue to be made and should be based on
reported AIDS cases adjusted for national underreporting. Projections should
also be made for patient subgroups defined by geography, gender, race/
ethnicity, and mode of HIV exposure.
TABLE 3. Projected numbers of acquired immunodeficiency syndrome (AIDS) cases,
by risk-behavior group*, United States, 1989-1993
Homosexual/bisexual men mHet erexual
male and female
Not intravenous Intravenous intravenous Heterosexual Perinatal
Year drug users drug users drug users transmission transmission
1989 26,000-28,000 2,600-2,800 11,000 2,600-2,900 1,000-1,100
1990 29,000-31,000 2,700-3,000 13,000-14,000 3,700-4,000 1,300-1,500
1991 30,000-38,000 2,600-3,400 14,000-18,000 4,800-6,100 1,600-2,200
1992 30,000-44,000 2,500-3,600 16,000-23,000 6,100-8,800 2,100-3,100
1993 30,000-48,000 2,400-3,800 17,000-27,000 7,600-12,200 2,600-4,100
Cumulative
total through
1993t 219,000-262,000 21,000-25,000 95,000-118,000 29,000-38,000 11,000-14,000
*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 for the first and third groups, and to the
nearest 100 for the other three groups).
tRounded to the nearest 1,000. Includes the following numbers of cases estimated to have been
diagnosed through 1988: 74,000 among homosexual and bisexual men who are not intravenous drug users (IVDUs); 8,600 among homosexual and bisexual men who are IVDUs; 25,000
among heterosexual male and female IVDUs; 4,200 attributed to heterosexual transmission;
and 1,900 attributed to perinatal transmission.

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