Stomach flu

A stomach virus (or stomach flu) is not a form of influenza but a condition that causes the stomach and intestines to become inflamed, resulting in a variety of uncomfortable, digestive-related symptoms. Stomach "flu" is universal, and for most people a private, and usually temporary, annoyance. The symptoms are nausea in the stomach, aches, fever and vomiting. The infectious agent is either a virus, bacterium or parasite.

According to the U.S. National Library of Medicine, there are many types of viruses that can cause this condition, chiefly:

• Norovirus: Norovirus is very contagious and can spread via a number of ways, such as through contaminated food, water or surfaces. It is also considered the most common cause of acute gastroenteritis.
• Rotavirus: The rotavirus belongs to the Reoviridae family of viruses, and is identified by its double-stranded RNA enclosed by a double-shelled outer layer. As with other viruses, it is very contagious and causes severe diarrhea among infants and children.
• Astrovirus: Astrovirus strains are single-stranded, positive-sense and non-enveloped RNA viruses belonging to the Mamastrovirus family. The virus is contagious among children and the elderly, but adults are more resistant to it.
• About 50% of stomach "flu" in winter months is caused by on of the 10 or so variations of the Norwalk virus, one of the caliciviruses.

1. Enteric diseases

1. Viral enteritis

1. Catarrhal diarrhoea
2. Gastric disorders

1. Infectious diarrhoeas
2. Colitis