NIH First hit for 'stomach flu' on Google viral gastroenteritis specified by NIH http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001298/ PubMed Health: Viral Gastroenteritis viral gastroenteritis viral gastroenteritis http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001298/ viral gastroenteritis specified by NIH various viruses specified by NIH http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001298/ various viruses viral gastroenteritis NIH