Nationwide outbreak of red eye syndrome associated with transfusion of leukocyte-reduced red blood cell units.

Objective: To characterize red eye reactions occurring within 24 hours after receipt of units of leukocyte-reduced red blood cells, determine their etiology, and investigate their potential link to transfusion.

Methods: We conducted a survey of transfusion facilities nationwide to determine the scope and magnitude of the reactions; performed case-control and cohort studies among transfused patients at the facility where most reactions occurred; and performed animal experiments, using cellulose acetate derivatives extracted from leukocyte-reduction filters and filter precursors, to reproduce reactions.

Results: From January 1, 1997, through January 15, 1998, we identified 159 reactions in 117 patients from 17 states.

Farm visits and undercooked hamburgers as major risk factors for sporadic Escherichia coli O157:H7 infection: data from a case-control study in 5 FoodNet sites.

In 1996, active surveillance in 5 Foodborne Diseases Active Surveillance Network (FoodNet) sites revealed up to a 9-fold difference in Escherichia coli O157:H7 (O157) infection incidence between sites. A matched case-control study of sporadic O157 cases was conducted in these sites from March 1996 through April 1997. Case subjects were patients with non-outbreak-related diarrheal illness who had O157 isolated from their stool samples.