Decreasing seroprevalence of human immunodeficiency virus type 1 in a regional blood donor population

Abstract
Blood banks have intensified their efforts to discourage donations from individuals at risk for the human immunodeficiency virus (HIV‐1). Since the onset of HIV‐1 donor screening in April 1985, a marked reduction in seroprevalence has been seen at the authors' institutions: from 51 cases per 100,000 donors in 1985 to 13 per 100,000 in the first 6 months of 1988. Data from 3.5 years have been analyzed for temporal trends in the association of HIV‐1 seroprevalence with donation site (urban vs. non‐urban) and donor gender. The association of HIV‐1 seropositivity with an urban donation site decreased through 1987 as the urban‐to‐nonurban donation odds ratio declined from 6.48 in 1985 to 2.54 in 1987. Despite this decrease, both men and women who donated in urban areas had a significantly higher seroprevalence than those in nonurban areas. Male donors had a higher overall HIV‐1 seroprevalence than female donors. However, the male‐to‐female odds ratio declined from 2.94 in 1985 to 1.96 in 1988, and male gender was no longer significantly associated with HIV‐1 seropositivity. This change in the donor profile appears to reflect declining numbers of seropositive men who acknowledge risk factors and greater numbers of women with no identified risks for HIV‐1. This study documents a dramatic decrease in HIV‐1‐seropositive donors and suggests that the deferral of high‐risk individuals has become increasingly successful.