Recent reports of fatal transfusion-associated Yersinia enterocolitica sepsis prompted a study of the feasibility of adding a question to the routine donor health history as a method of reducing this risk. In three American Red Cross blood centers, 11,323 donors were asked one of two questions about gastrointestinal symptoms during their health history screenings. Affirmative responses were obtained from 0.6 or 4.0 percent of the donors, depending on how the question was asked. In one center, more than 6 percent of donors gave affirmative answers. The efficacy of asking a relatively simple question about gastrointestinal symptoms as a way of preventing Y. enterocolitica should be evaluated further, because relatively large numbers of donors may respond affirmatively. Other methods of reducing the risk of transfusion-associated Y. enterocolitica infection should be pursued.