Acute diarrhoea, or stomach flu, is common. Diarrhoea is defined as having stools more than three times a day that do not have a solid consistency. The consistency can vary from mushy to watery. Watery stools indicate an infection. Diarrhoea is almost always an infectious condition, especially acute diarrhoea.
The term “stomach flu” makes people think of influenza, in other words a virus. But stomach flu does not necessarily have to be caused by a virus. In fact, stomach flu is gastroenteritis, an acute inflammation of the lining of the stomach or intestine. There are various causes of stomach flu. It can result from infection with a virus, bacterium or intestinal parasite.
Causes of stomach flu
- With stomach flu or a viral infection, the symptoms will pass quickly, but in some cases you can become seriously ill.
- In 8% of cases, a bacterial infection is the cause of diarrhoea and is caused by contaminated food.
- Infection with Clostridium difficile causes diarrhoea. This is a bacterium that can be contracted in hospital.
- Giardia lamblia is an intestinal parasite that causes diarrhoea which can persist for a long time.
- Cryptosporidium is a parasitic infection that usually resolves on its own after a few days, but can cause severe diarrhoea.
Viral infection
The term “stomach flu” is used for acute diarrhoea when you have not eaten anything bad. With food poisoning, several people are often infected and you usually know which food caused the symptoms. Viral infections are common, especially in children. A virus was the cause in 58% of children with diarrhoea.
The most common cause of stomach flu is infection with rotavirus or norovirus. In both cases, severe diarrhoea, nausea and abdominal pain develop; fever is also common. The severe diarrhoea of viral stomach flu almost always resolves on its own within a day or a few days. Sometimes the symptoms are mild and last 24 to 60 hours. Viral diarrhoea is seasonal, peaking in winter. Children are easily infected at childcare centres. Good hygiene can prevent a large proportion of cases.
Stomach flu worldwide
A study of worldwide mortality from diarrhoea caused by rotavirus in children shows that:
- 111 million episodes of gastroenteritis are experienced by children at home;
- 25 million clinic visits take place;
- 2 million hospital admissions occur;
- there are 440,000 deaths (352,000-592,000 ) among children under 5 years of age;
- by the age of five, almost every child will have experienced an episode of rotavirus.
Rotavirus and mortality
In most cases, the cause of acute stomach flu in children is norovirus type 2, while older people are more likely to be affected by rotavirus.
If there is substantial fluid loss, older people or children sometimes need to be admitted to hospital.
The number of children with stomach flu who experience a rotavirus infection each year in the United States:
- 3 million children;
- 500,000 children end up in the emergency department;
- 70,000 children ( 6% of all hospital admissions of children under 5 years of age.
Sources
Emerging Infectiuos disdease Volume 9, Number 5—May 2003
Global Illness and Deaths Caused by Rotavirus Disease in Children
Umesh D. Parashar* , Erik G. Hummelman*, Joseph S. Bresee*, Mark A. Miller†, and Roger I. Glass*
