The first reliable small-animal model for human norovirus infection, a notorious cause of the illness known as stomach flu, should help researchers to better understand the biology of these pathogens — and might lead to treatments.

Noroviruses are the leading cause of food-borne illness, and the vomiting, nausea, diarrhoea and stomach cramps that go with it. Every year, the viruses cause around 700 million infections and kill more than 200,000 people — at the expense of US$60 billion in lost productivity and healthcare costs. Until now, the only animal models, including large animals such as chimpanzees and pigs, have been unsuitable.

Now Joana Rocha-Pereira, at KU Leuven in Belgium, and her colleagues report successfully cultivating human noroviruses in the larvae of zebrafish (Danio rerio), a freshwater minnow that shares many genes with humans and is a well-established animal model of human disease.

The model should help to identify the key determinants for human norovirus infection, and — to the relief of many parents — expedite the development of antiviral drugs.