The stomach bug norovirus has broken out at Auckland's Middlemore Hospital.
Initially brought into the hospital from community admissions, the virus has now spread across wards and both staff and patients have been affected.
As of today 14 people have fallen ill, the hospital said.
Middlemore is now on alert, and is asking visitors to take extra precautions.
Visitors to affected wards of the hospital may be asked to wear gloves and gowns before entering.
Staff recommend not bringing children in to the hospital during a norovirus alert. They are asking that anybody who is visiting patients at Middlemore Hospital be well and show no symptoms of illness and have been symptom-free for at least two days.
Any visitors are also asked to perform rigorous hand washing with soap and water before and after visiting Middlemore. Hand gel is not effective for gastroenteritis, the hospital says.
Norovirus, or viral gastroenteritis, causes nausea, abdominal pain, vomiting and diarrhoea.
Symptoms usually last from 12 to 72 hours.
A norovirus outbreak hit Middlemore, Hamilton and Tauranga hospitals in 2012.
More than 100 patients and staff at Middlemore Hospital were affected by the virus during the previous outbreak.
The hospital was forced to close some wards to control the spread of the infection during the 2012 outbreak.
To avoid the virus, the hospital says people in the community should also hand wash with soap and water directly after going to the toilet and before preparing food as it helps to stop the spread of infection.
If you are unwell, drink plenty of fluids and avoid contact with infants, the elderly or those with long term illness until you are free of all symptoms for a minimum of 24 hours.
For more information go to Auckland Regional Public Health website.
- Fairfax Media