Doctors call it acute viral gastroenteritis. Unlike "true" flu, which is caused by the influenza virus, common causes of viral gastroenteritis include rotavirus, norovirus, astrovirus, adenovirus and many more. Formal diagnostic testing is rarely performed because the disease is so easily identified on the basis of its major symptom--severe, watery diarrhea.
The Centers for Disease Control and Prevention (CDC) reports that symptoms usually start one to two days after exposure to the causative agent. In many cases, patients can identify the source by a review of sick contacts or exposures to suspect food or water.
According to MayoClinic.com, symptoms usually last just a day or two. However, in rare cases, they may last for up to 10 days. People with more persistent symptoms should contact their physician for advice.
In addition to diarrhea, common complaints include nausea, vomiting, cramps/abdominal pain, headache, muscle aches and low-grade fever. Diarrhea due to viral gastroenteritis is watery; bloody diarrhea warrants a trip to the doctor.
Physicians Joan Butterton and Stephen Calderwood caution in "Harrison's Principles of Internal Medicine" that acute diarrheal illnesses such as viral gastroenteritis constitute a major cause of severe illness and death in developing countries, mainly due to dehydration. Although death is rare in the United States due to the availability of simple medical treatments such as intravenous hydration, caregivers of young children, the elderly and people with other medical problems still should remain vigilant for signs of dangerous fluid depletion.
Unfortunately, CDC officials advise that there is no specific cure for viral gastroenteritis. Caregivers should concentrate on replenishing fluids and electrolytes lost in the diarrhea. According to the American Academy of Family Physicians, good choices include diluted juice, broth, sports drinks and oral rehydration solutions. Commercial brands include Pedialyte and Ricelyte. Caregivers can make their own solution by combining 8 tsp. sugar, 1 tsp. salt, 1 cup orange juice and 4 c. water.
According to the Mayo Clinic, most cases of viral gastroenteritis can be prevented by good health habits such as washing hands after using the bathroom and before eating, following safe food handling techniques and avoiding suspect food and water. After caring for someone with viral gastroenteritis, caregivers should thoroughly clean objects the sick person has handled, including linens, utensils and even door handles.