A Point Source Outbreak of Chronic Diarrhea in Texas: No Known Exposure to Raw Milk

To the Editor.— Osterholm et al 1 report in this issue of JAMA an outbreak of chronic diarrhea that was attributed to the consumption of raw milk. Although they report that several additional outbreaks have been associated with raw milk, we observed an apparent point source outbreak of chronic diarrhea in Texas in which an association with raw milk was not found. Study.— The Texas outbreak was identified early in 1985 when one of us (L.J.H.) identified several patients with frequent, urgent diarrhea that had lasted several months. In cooperation with the Texas Department of Health, an investigation was performed using the following case definition: an individual who averaged more than three unformed bowel movements per day for at least one month, had no known pathogen isolated from the gastrointestinal tract, and had no known etiology for the condition. A written request was made