Four US states have confirmed Cyclospora cases associated with salad. More states could follow. Wisconsin, Minnesota and Ohio have already reported cases. Illinois is being examined. The parasite causes long bouts of diarrhoea, abdominal cramps and fatigue. Officials caution that fresh salads pose a risk. UK shoppers are advised to rinse all bagged leaves thoroughly. Run cool water over each leaf before eating. Scrub firm greens including cabbage thoroughly. Soap is unrequired; just water does the job.