People in NSW are encouraged to stay on alert for symptoms of gastroenteritis, with testing and hospital data showing a significant rise in cases in recent weeks across the state.
Rotavirus is one common cause of viral gastroenteritis and can be particularly severe in young children.
The latest testing data shows rotavirus notifications are at some of their highest levels of the last decade.
In the first two weeks of 2023, 197 cases of rotavirus were identified, compared with about 40 cases during the same period usually.
Director of NSW Health's One Health branch Keira Glasgow said reducing the spread of gastro before schools returned in the next few weeks is important.
"Last week, there were more than 2,250 presentations to NSW emergency departments with symptoms of gastroenteritis. Presentations were particularly high in children under five years old, and in children aged five to 16 years old," Ms Glasgow said.
"The message to the community is clear – simple measures can help stop the spread of gastro. Maintaining good hand hygiene and keeping children at home when they are unwell will give us a good chance to slow the spread before February, when children will all be back together at school."
Viruses are spread from the vomit or stool (faeces) of an infected person. This can occur when cleaning up body fluids, during person-to-person contact, sharing of contaminated objects and occasionally inhaling airborne particles when people vomit.
Viral gastroenteritis symptoms include nausea, vomiting, diarrhoea, fever, abdominal pain, headache and muscle aches. They can take up to three days to develop and usually last between one or two days, and sometimes longer.
Advice for parents and caregivers includes:
Immunisation to prevent rotavirus infection is recommended and part of the childhood immunisation schedule. Immunisation is free for children under six months of age. The vaccine is given as two oral doses, at six weeks and four months of age, with completion of the course by 24 weeks of age.
The main treatment for viral gastroenteritis is to rest and drink plenty of fluids. Most people recover without complications but more urgent care may need to be sought for infants, people with suppressed immune systems, and the elderly, who may experience more serious illness.
For information on how to prevent the spread of gastroenteritis visit