Blood donor deferral in Minas Gerais State, Brazil: blood centers as sentinels of urban population health.

Background: Shortage of safe blood donors is frequent and it is important to understand the causes of deferral of potential donors, who reside mainly in urban areas, to improve recruitment campaigns aiming at the quality/availability of donors.

Study Design And Methods: In Minas Gerais State, Brazil, Hemominas Foundation collects, analyzes, and distributes more than 90 percent of blood. Blood is collected in 19 centers in cities.