Jt. Murphy et al., REDEFINING THE GROWTH OF THE HETEROSEXUAL HIV AIDS EPIDEMIC IN CHICAGO/, Journal of acquired immune deficiency syndromes and human retrovirology, 16(2), 1997, pp. 122-126
A dramatic shift in the relative distribution of the five categories o
f heterosexual transmission for AIDS cases diagnosed in Chicago since
1991 prompted a mode-of-transmission validation study of what had beco
me the most frequently reported heterosexual exposure: heterosexual re
lations with a person with AIDS (PWA) or documented HIV infection whos
e risk is not specified. Methods: For 395 cases with originally report
ed heterosexual exposure, one or more of three supplemental data sourc
es were employed: medical records were reviewed, medical providers wer
e interviewed, and patients or proxies (i.e., spouse, significant othe
r, or family member) were interviewed when possible. When reported HIV
exposure could not be validated or reclassified, the transmission cat
egory employed was ''no identifiable risk'' (NIR). Results: Eighty-fiv
e percent (336 of 395 cases) were reclassified into different transmis
sion categories. Most notably, 69% (272 of 395 cases) were reclassifie
d into transmission categories that did not involve heterosexual conta
ct, including NIR. The cumulative percentage of cases attributable to
heterosexual contact declined from 8% to 5% as a result of reclassific
ation. Additionally, reclassification resulted in a reduction of nearl
y 50% in the number of AIDS cases attributable to heterosexual contact
diagnosed in 1993 and 1994. Conclusions: In Chicago, an emerging prob
lem in AIDS surveillance appears to be the use of an ambiguous heteros
exual exposure category as a default when other information is not rea
dily available. This study has found the growth in AIDS cases among pe
rsons exposed to HIV through heterosexual contact to be much slower th
an previously perceived. This finding may have important implications
for the national debate over the extent to which heterosexual people a
re being infected and how funding and prevention strategies should be
prioritized.