What Causes Gastroenteritis?

Gastroenteritis is usually contracted by eating or drinking contaminated food or water, or by sharing food, utensils or towels with someone who's infected. The infection may be caused by bacteria such as salmonella, campylobacter or E.coli or by a number of viruses including rotaviruses and Norwalk-type viruses.

Rotaviruses

These viruses are one of the most common causes of infectious diarrhoea, and are a leading cause of death among children worldwide. In the UK, it is estimated that 1 in 38 children need to be hospitalised for rotavirus gastroenteritis by the age of 5, and that 14 children under the age of 5 will die from complications of the disease every year.

Rotaviral gastroenteritis may be passed on through contaminated foods such as shellfish and contaminated water, or they can be passed from person to person, particularly through the faecal-oral route - that is, someone with the virus handles food without washing their hands after using the bathroom.

Children usually become infected when they put their fingers or other objects contaminated with the virus into their mouths. Even tiny amounts of rotavirus may cause a serious illness. Adults who are infected may not experience any symptoms, but can still spread the disease, which can be a concern if they work in large institutions or with food preparation. Anyone with rotavirus infection will generally be contagious for about 10 days after their symptoms appear; however, some may remain contagious after symptoms disappear.

Norwalk-Type Viruses

Norwalk-type viruses (or noroviruses) are responsible for large scale viral gastroenteritis outbreaks, sweeping through communities, particularly in places with a high concentration of people, such as schools and universities. Sufferers begin to feel ill within 3 days of contracting the virus, but will start to feel better about 2 days later. However, they may remain contagious for up to three weeks after they have recovered.