THE ROLE OF THE PRESYMPTOMATIC FOOD HANDLER IN A COMMON SOURCE OUTBREAK OF FOOD-BORNE SRSV GASTROENTERITIS IN A GROUP OF HOSPITALS

A common source outbreak of small round structure virus (SRSV) gastroenteritis affected 81 patients and 114 staff in four hospitals served by one central hospital kitchen. Eating: salad items was found to be significantly associated with illness. In a cohort study of a staff buffet function eating turkey salad sandwiches was associated with illness (relative risk = 2.4; 95% CI = 1.4-4.1; P = 0.003), and a case control study of patients in one hospital showed an odds ratio of 6.6 (95% CI = 1.0-71.6; P = 0.04) for eating tuna salad and becoming ill. One of two food handlers who prepared the salads became ill the day following food preparation; she also had a young child at home who had been ill with a gastrointestinal illness during the previous two days. Contamination of food by mechanical transmission of the virus from the child via clothes and hands of the mother, or pre-symptomatic faecal excretion in the mother are possible explanations of contamination of food.