Stomach Bug Going Around 2025. Norovirus, commonly known as the winter vomiting bug (although it can strike at any time of year), is a stomach bug that causes sickness and diarrhoea. When people think they have the stomach flu or a stomach bug, it’s probably norovirus, the agency added.

It is sometimes called the stomach flu or the stomach bug. however, norovirus illness is. Here’s what to know about symptoms and the spread.