In 1997, a community-wide outbreak of Salmonella enterica serotype Typhimurium
(S. typhimurium) infection occurred in France. The investigation included case searching and a
case-control study. A case was defined as a resident of the Jura district with fever or diarrhoea
between 12 May and 8 July 1997, from whom S. typhimurium was isolated in stool or blood.
One hundred and thirteen cases were identified. Thirty-three (83%) of 40 cases but only 23
(55%) of 42 community controls, matched for age and area of residence, reported eating
Morbier cheese (Odds ratio: 6·5; 95% Confidence Interval: 1·4–28·8). Morbier cheese samples
taken from the refrigerators of two case-patients and one symptom-free neighbour cultured
positive for S. typhimurium of the same phage type as the human isolates. The analysis of
distribution channels incriminated one batch from a single processing plant. These findings
show that an unpasteurized soft cheese is an effective vehicle of S. typhimurium transmission.