Food Safety Report: Costco Wholesale, East 800 South, Orem, UT, USA 9 months ago • details 74 Suspected food poisoning. Symptoms: Diarrhea, Stomach Pain, Cramps Suspected source: costco red seedless grapes Onset: 4 to 12 hours Duration: 12 to 24 hours Additional information: i was not the only person to experience these symptoms