In Arbourgh v. Sweet Basil Bistro, Inc., 98-2218 (La.App. 4 Cir. 5/19/99); 740 So. 2d 186, writ denied, 99-2942 (La. 12/17/99); 751 So. 2d 883, the plaintiffs proved causation, in part, with medical tests showing that their child had ingested the compylobacter bacteria. One source of that organism is undercooked chicken, which the plaintiffs' son had consumed at the defendant's restaurant the day he became ill.