NLVs are the major cause of non-bacterial gastroenteritis or food poisoning. Possibly it can also be airborne on droplets or be spread by inanimate objects such as books or toys. One to two days after infection the patient starts to vomit. The person may be in a community setting like a nursing home, hospital, restaurant, summer camp, on a cruise ship, in a day care center, or eating a catered meal. The food eaten may be oysters, fresh fruit or vegetables, water, ice, or bakery products.
Outbreaks are most common in the winter but can occur at other times.
Vomiting is followed by abdominal pains and diarrhea with 4 to 8 loose to watery non-bloody stools with no mucus. The whole illness only lasts one or two days. This illness is second in frequency only to the common cold. It causes 5 million deaths in children and 25 days lost from school or work per 100 persons annually. There are no after effects.