In the early 1990s, HIV seroprevalence was highest at the Miami homeless cl
inic among 16 homeless sites participating in a nationwide sentinel survey.
To examine dynamic seroprevalence patterns in Miami's homeless clients in
relation to demographics and risk behaviors over six years, we analyzed dat
a from an unlinked (blinded) serosurvey of clients attending the principal
primary care clinic serving Miami's homeless. Data were from 3,797 medical
encounters with homeless persons who, on their initial clinic visit within
an annual survey period, received routine serologic testing and a risk beha
vior survey. Overall HIV seroprevalence was 15.9% and infection rates for m
en (16.4%) and women (14.5%) did not differ. Seroprevalence for blacks (19.
9%) was significantly higher than for Hispanics (9.1%) or whites (8.3%) (p
< 0.0001). Seroprevalence was 12.6% (35 times the national rate) for client
s reporting heterosexual contact as their only risk. Significant increases
in seroprevalence, above this heterosexual-contact-only 'baseline', were fo
und for clients disclosing high-risk behaviors: male-to-male sex, drug inje
ction, receiving or giving money/drugs for sex, and sexual contact with a d
rug injector or HIV-infected partner (p < 0.0001). Seroprevalence declined
over six years from 23.2 to 7.2% (p < 0.0001). Significant downward trends
were observed for men and women, blacks and Hispanics, men who have sex wit
h men, and clients reporting heterosexual contact. The proportion of client
s reporting high-risk behaviors decreased sharply (p < 0.0001). Elevated HI
V seroprevalence in Miami's homeless clients was strongly associated with h
igh-risk behaviors. Expansion of HIV prevention and HIV/drug treatment serv
ices for homeless persons is strongly recommended.