Stomach flu, also referred to as viral gastroenteritis, is an inflammatory condition of the gastrointestinal (GI) tract caused by viral infection. Despite the name, it is neither a referred sign of the common flu disease nor is it caused by the influenza virus. In fact, many viral species are capable of causing flu, of which some are rotavirus, adenovirus, astrovirus, and sapovirus. It is not a very serious medical problem, and effective recovery is achieved with a well-planned diet, and drinking ample amounts of healthy fluids.