Stomach Bug 2024 Lasting A Long Time After Eating. Here's what you need to know if you think you have the norovirus, commonly called the stomach flu or stomach bug, and how to prevent spreading the sickness. How long does gastroenteritis last?

Stomach flu usually improves within a few days, but the exact duration depends on the underlying pathogen. Whether your gastro is down to food poisoning, a virus or stomach flu, there’s nothing pleasant about vomiting and diarrhoea.