Gastroenteritis (often referred to as the stomach flu , however, it is not related to the influenza virus. Gastroenteritis is a nonspecific term for various inflammatory problems in the gastrointestinal tract with the most common symptoms and signs being diarrhea, nausea, vomiting, and abdominal pains.s previously mentioned, although it is not caused by influenza viruses, gastroenteritis is commonly referred to as the stomach flu because most people have acute symptoms that last a day or so, and then begin to resolve, like the symptoms of more benign flu strains.