A restaurant-associated outbreak of Brainerd diarrhea in California.

In a rare outbreak of Brainerd diarrhea in California, we identified 23 patients, many of whom had diarrhea persisting for > or =6 months. Case-control studies revealed that illness was associated with 1 local restaurant but not with any specific food or beverage. A Campylobacter species was detected in some patients' stool specimens, but its role in the outbreak remains unclear.