The gastro bug


Viral gastroenteritis mostly affects young children between 6 months and 2 years of age. It’s a common infection in babies and young children causing diarrhoea (runny, watery stools) and vomiting. While most young children only suffer mild tummy upsets, the biggest effect of vomiting and diarrhoea is dehydration, which is a serious condition.

Gastroenteritis is mostly caused by the rotavirus, which is usually caught through a child touching a contaminated person or object, then transferring the germs to their mouth. Most children will come into contact with the virus but once they have had it, they are unlikely to get it again, as the immunity to rotavirus is long-lasting.

what are the symptoms?

Gastroenteritis usually starts with diarrhoea (which often lasts up to 10 days), as well as vomiting and feeling sick. Some children might also have a fever, runny nose, cough and tummy pains.

The danger with gastroenteritis is that young children (particularly babies) can easily become dehydrated through vomiting and diarrhoea. A mildly dehydrated child has increased thirst and a slightly dry mouth. A moderately dehydrated child may be lethargic, have a dry mouth, sunken eyes, fewer wet nappies than normal, and darker urine. A good indicator of dehydration is the colour of your child’s urine: clear or light-coloured urine means they’re well hydrated, whereas a dark yellow or amber color usually signals dehydration. A severely dehydrated child may be drowsy and limp, have cold hands and feet, and a rapid pulse. Dehydration in babies can also show as a sunken soft spot on the front of the head (the fontanel). If your baby or child has signs of moderate to severe dehydration, you must seek urgent medical attention.

how can i help my child?

The best way to help a child with gastroenteritis is to give plenty of fluids while the child is ill, aiming to avoid dehydration. This is called fluid replacement. Often children do not feel like eating or drinking when they are sick, which makes the problem worse; however, you should encourage them to sip some type of fluid regularly (every five minutes), offering small amounts at a time.

If you are breastfeeding, feed on demand. You may need to feed more often and you could even offer extra fluid, such as boiled water. If your baby is on formula, continue to give full-strength formula feeds. Older children might be persuaded to drink very diluted cordial or fruit juice, or even sip some clear water-based soups, such as chicken broth.

If necessary, for babies and children who are weaned, there are over-the-counter oral rehydration fluids and powders you can add to water which are products designed to replace fluids, sugar, and electrolytes (dissolved minerals such as sodium, potassium, and chloride).

Within four hours after vomiting stops, the BRAT diet (bananas, rice, apples, toast, and other simple starches, such as noodles or potatoes) may be started in children who are weaned from formula or breast milk.

For fevers and tummy pain, you can give children’s pain relief, using the recommended dosage for your child’s age and weight.

To avoid the spread of germs within your household, ensure thorough hand washing and drying before handling food, after the toilet and changing a nappy; avoid sharing food and drink; disinfect surfaces such as toilets, bathrooms, changing tables and kitchen surfaces; replace tea towels and hand towels daily; and keep the sick child away from other children for at least 24 hours after vomiting and diarrhoea has stopped.


A vaccination against rotavirus is available, but is not part of the government-funded vaccination schedule. It can be bought and is recommended for babies aged between 6- to 24-weeks. See your doctor or Well Child provider for more information.

when to see a doctor

If your child is less than 6-months old and has vomiting or diarrhoea, or if your child is showing signs of dehydration, you should consult a doctor. If your child seems to be getting sicker, you should also take them to the doctor to be checked.

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