A stomach virus, or viral gastroenteritis, is an intestinal virus that's contracted by contact with another infected person or by ingesting contaminated water or food. A variety of signs accompany a stomach virus, ranging from vomiting and pain to cramps and fever. While most healthy people recover naturally after experiencing the first signs of a stomach virus, small children and those with compromised immune systems should pay attention to the symptoms because they can cause serious complications that can lead to death, report doctors at the Mayo Clinic.
Stools are usually watery when diarrhea occurs with a stomach virus. If there is blood in the stools, that usually means something else is going on. Diarrhea may begin anywhere from one to three days after the patient has become infected with the virus. Symptoms usually last for a day or two, but can continue for as long as 10 days. Symptoms of bacterial infections from food poisoning often mimic the symptoms of the flu, with the same level of diarrhea.
Nausea with vomiting is a common symptom of the stomach flu. Vomiting may continue for a couple of days. If there is blood in the vomit, it could be a sign of a more serious complication and should be checked by a physician, report doctors at the University of Michigan Health System.
Patients may become dehydrated and should try to keep liquids down until the vomiting ends. Signs of dehydration include excessive thirst and dry mouth, a decrease in tears and little or no urine output. While the vomiting and diarrhea contribute to lethargic and weak feelings, extreme tiredness also can be an early sign of dehydration that should be treated with liquids or intravenous fluids.
Aches and muscle pains usually accompany a stomach virus. Abdominal pains are common. Cramping is one of the first signs of a stomach virus and is usually followed quickly by a loss of appetite.
There may be a low-grade fever in the early stages of the virus, and patients often complain of headaches. While the temperature may indicate signs of a fever, the patient typically has chills as well, report doctors at the National Digestive Diseases Information Clearinghouse. Lab tests can rule out other problems such as appendicitis, which often mimics the early symptoms of a stomach virus.