Student health services at a Washington, D.C., university reported an outbreak of gastrointestinal illness in late March. Telephone calls were used to conduct a case-control study to determine a source of the illnesses. Electronic records of 49 student's meals were available through the university's dining hall. Eating at the dining hall was associated with illness, specifically eating from the deli area. Stool specimens were collected, and found to contain Rotavirus, type A, genotype combination P[4],G2A. Dining hall workers were questioned and several had reported recent gastrointestinal illness. One food worker was suspected to the cause of the outbreak.