It sounds like what you and your wife contracted was norovirus, not food poisoning. As nurses, you know that the best way to prevent getting noro is frequent hand washing, keeping hands off handrails, not touching your eyes or mouth, etc.
Also, you probably also know that noro gives symptoms both "upper" and "lower" as the virus works its magic through your body. It usually takes a day and a half to feel human again. Was that your experience?