Rotavirus in children: how it runs, why it is dangerous and what to do

Rotavirus is one of the most common causes of acute gut infection in young children. Parents usually call it “stomach flu” or “food poisoning”, although the infection has nothing to do with influenza or spoiled food: the virus passes from person to person and is highly contagious.

How it usually runs

The typical picture: the illness starts suddenly with vomiting and a raised temperature, and within a few hours or by the next day profuse watery diarrhoea joins in. The vomiting usually stops earlier than the diarrhoea, and the diarrhoea can persist for several days. In most children everything resolves on its own, provided dehydration has been avoided.

• The onset is abrupt, often at night.
• Vomiting is usually at its worst in the first 24 hours.
• The diarrhoea is watery and profuse, without blood.
• The fever is more often moderate, but it can be high.
• The child refuses food — this is expected and not dangerous in itself.

Who gets it worse

The infection is hardest in the first two years of life: dehydration develops faster and the margin of safety is smaller. Older children and adults get it too, but usually more mildly — sometimes so mildly that they carry it as a slight upset and remain contagious to the younger children in the family.

The main risk is fluid loss

The combination of vomiting, diarrhoea and fever means fluid is being lost by three routes at once. A child who has stopped drinking, or cannot keep down what they drink, needs an examination even if they look calm on the outside. The signs of fluid shortage — and why the severity of dehydration cannot be determined at home — are covered in a separate article.

Is a rotavirus test needed

A rapid test can confirm that the infection is rotaviral. It changes little about how you monitor the child at home: fluids and assessment of the child's condition are needed with any gut infection. A test can be useful when the cause matters — for example with a drawn-out course, in a childcare setting, or when the picture is not quite typical. The decision about testing is made by a doctor.

What helps and what does not

• Helps: frequent drinks in small amounts, oral rehydration solutions, continuing breastfeeding, calmly watching urination and activity.
• Does not work: antibiotics — they have no effect on viruses and are not prescribed for a viral gut infection.
• Not decided at home: anti-sickness and anti-diarrhoeal medicines are not given to children without a doctor.
• Not required: prolonged restrictive diets; normal age-appropriate food returns as soon as the child is ready to eat.

Prevention

The virus is extremely resilient and spreads easily, so ordinary measures — handwashing, separate dishes and towels, cleaning surfaces — reduce the risk but do not remove it entirely. Vaccines against rotavirus infection exist, and the World Health Organization recommends including rotavirus vaccination in national immunization programmes.

How long a child stays contagious

The virus is shed both before symptoms appear and for some time after they disappear, so “isolating after recovery” cannot fully work. The practical conclusion is simple: in a family with several children it is worth stepping up hygiene in advance rather than waiting for the first symptoms in the youngest.

This page is for general information only and is not a substitute for a consultation with a doctor. A child's diagnosis and treatment are determined by a doctor during an examination.