Protracted outbreak of Salmonella typhimurium definitive phage type 170 food poisoning related to tripe, 'pig bag', and chitterlings.

An outbreak of food poisoning around South Yorkshire due to Salmonella typhimurium definitive phage type 170 related to eating tripe, 'pig bag', and chitterlings was associated with a common supplier. Possible links with other suppliers were considered. Twenty-two cases occurred between 11 April 1995 and 7 May 1995. The situation was complicated by the complex distribution network of suppliers and by possible cross contamination in the retail outlets. This complexity created difficulties in the collection, recording and subsequent analysis of the data. The investigation of the outbreak and the subsequent control measures are discussed. Some of the difficulties of monitoring foodborne intestinal disease are highlighted.