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Key points about gastroenteritis

If your baby is less than 6 months old and has vomiting or diarrhoea see a health professional urgently. Pēpi (babies) can quickly become dehydrated and unwell.

  • gastroenteritis (gastro) is a bowel infection causing diarrhoea, and sometimes vomiting
  • diarrhoea means runny, watery poo
  • tamariki need to drink plenty of fluids - give small amounts of fluid often
  • gastro can cause dehydration, especially in pēpi and young tamariki, and make them unwell 
  • watch for signs of dehydration (fewer wet nappies, sunken eyes, unusual sleepiness) and take your child to a health professional  urgently if you’re worried
  • if your baby is less than 6 months old and has vomiting or diarrhoea,  see a health professional urgently - pēpi can quickly become dehydrated and unwell

What is gastroenteritis?

Gastro is a bowel infection which causes runny, watery poo and sometimes vomiting.

Gastro affects all age groups, but is more common, and can be worse, in pēpi and young tamariki.

The vomiting may settle quickly but the diarrhoea often lasts for several days. This is OK as long as your child is drinking well and seems to be improving.

You can expect your child to get completely better.

Signs and symptoms of gastroenteritis

The most common symptoms of gastro are:

  • runny, watery poo (diarrhoea)
  • feeling sick (nausea)
  • vomiting

Tamariki with gastro may also have:

  • a fever
  • tummy pains

Causes of gastroenteritis

Viral

A virus usually causes gastro. Common viruses are rotavirus, norovirus and adenovirus, but there are many others. Gastro is very common and tamariki can get it more than once.

Pēpi younger than 15 weeks of age can have rotavirus vaccination free of charge. This protects against one of the most common causes of gastro.

Rotavirus Immunisation

Bacterial

Sometimes bacteria can cause gastro, but this is much less common. This can cause blood in the poo.

How children catch viral gastroenteritis

The virus is easily spread in homes, daycare, kindergartens and schools. 

A child can catch viral gastro by touching something (like a cup) that has been in contact with someone who has gastro.

When to seek help for a child with gastroenteritis

Always see a health professional urgently if your child has vomiting or diarrhoea and is under 6 months old. Pēpi can quickly become dehydrated and unwell.

Call Healthline on 0800 611 116 or see a health professional urgently if your child: 

  • is drowsy and difficult to wake
  • has a lot of diarrhoea (8 to 10 watery motions in 1 day)
  • is vomiting and can’t keep fluids down
  • has blood in their poo
  • starts vomiting green fluid (bile)
  • has severe tummy pain
  • shows signs of dehydration
  • is unwell and you are worried for any reason

See a health professional if your child's diarrhoea continues for more than 10 days.

Call 111 within New Zealand for urgent medical help (use the appropriate emergency number in other countries).

Caring for children with gastroenteritis at home

Small amounts of fluid often

The main treatment is to keep giving your child fluids. Offer small amounts of fluid often.

Keep offering your child fluids even if they are vomiting.

Types of fluids

Continue to give your child what they usually drink. If you are breastfeeding, continue to feed on demand - you may need to feed more frequently. 

You can also give your child the following drinks diluted with water:

  • apple juice - mix 1 part juice to 1 part water 
  • fizzy drinks such as lemonade - add 1 part of warm water to 1 part of fizzy drink (warm water removes the bubbles)
  • cordial - make up to normal drinking strength, then add 1 part of water to 1 part cordial
  • soup - add 1 part of water to 1 part of soup
This illustration shows a visual representation of a drink dilution method. It features three glasses: the first glass contains "1 part water," the second glass contains "1 part juice or fizzy drink," and the third glass illustrates the combined "diluted juice or fizzy drink."

Your health professional may recommend rehydration solutions (such as Hydralyte) if your child is dehydrated. You can get these from your pharmacist - follow the instructions on the packet.

Nappy rash

Diarrhoea can cause a nappy rash. After each poo, wash and dry your baby’s bottom well and then put on a protective cream or ointment (such as Vaseline or zinc and castor oil cream).

Eating with gastroenteritis

Your child may refuse food at first - this is OK as long as they take fluids. 

Most tamariki will start eating again as they start to get better. It’s fine for them to eat even if diarrhoea continues.

Treating gastroenteritis

The main treatment is to keep giving your child fluids. 

Don’t give your child medicines to reduce diarrhoea. They can be harmful for tamariki.

A health professional may occasionally prescribe a medicine for vomiting. Follow the health professional’s instructions.

Tamariki with viral gastro don’t get better with antibiotics. Antibiotics are used to treat bacterial infections.   

Signs of dehydration

The younger the child, the easier it is for them to become dehydrated.

Signs of dehydration:

  • fewer wet nappies or not weeing as much as usual
  • sunken eyes
  • cold hands and feet
  • being drowsy or difficult to wake 

If your child has any of these signs, take them to a health professional urgently.

Preventing gastroenteritis from spreading

Gastro spreads very easily. There are ways to help prevent gastro from spreading.

Thorough handwashing

Handwashing or using hand sanitiser is especially important after going to the toilet, after nappy changing and before handling food. Encourage your child to clean their hands after using the toilet.

Cleaning toilet and bathroom areas

It’s a good idea to thoroughly clean your toilet and bathroom areas.

Washing dirty clothes

Wash your child's dirty clothing straight away.

Avoiding sharing food and drinks

Make sure your child doesn't share food, drinks, cups, drink bottles and utensils with anyone.

Keeping away from others

Keep your child away from others until the vomiting and diarrhoea have stopped. Keep tamariki with diarrhoea away from daycare, kindergarten and school until there has been no diarrhoea for 48 hours.

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