People with winter ailments resulted in a record number of patients turning up at Hawke's Bay Hospital's Emergency Department on Monday.
Respiratory and flu-like illnesses were the main reason for the increase, with 156 people treated.
Hospital chief medical officer John Gommans urged people to see their family doctor early if feeling unwell, especially if they had a chronic respiratory illness.
With cold weather predicted over the next few days the hospital anticipated more people needing care.
People should stay warm, receive an influenza vaccine and see a doctor early if feeling unwell, Dr Gommans said.