An unexplained rise in medical cases has pushed Waikato Hospital into overload as it struggles to deal with numbers beyond its capacity.
Hospital assistant group manager Kevin Harris earlier this week issued a statement to staff asking for their help in reducing a 103 per cent occupancy rate.
He highlighted a recent spike in the number of medical and respiratory cases, combined with gastric symptoms including vomiting and diarrhoea, for the pressure on resources.
''There doesn't appear to be one common cause - for example we are seeing all sorts of cases from chest pain, to pre stroke symptoms, rashes, diarrhoea and vomiting, seizures and respiratory problems,'' he said.
St John Hamilton team manager Nigel Dawson said the ambulance service had also noticed a higher than normal volume of callouts.
''We get a lot more respiratory infections in the winter which is traditionally our busiest months but it just hasn't gone quiet like it normally does over the Christmas/New Year period,'' he said.
Ambulance callout rates in December 2012 were 4.8 per cent higher than December 2011.
''And there have been a lot of medical-based callouts and no explanation as to why,'' Mr Dawson said.
On Monday and Tuesday this week 327 people were treated in the Waikato Hospital emergency department while 319 were treated on the equivalent days last year.
Mr Harris said the flow-on effect from high numbers through ED was slowing patient flow due to a lack of beds available.
Waikato Hospital has 531 inpatient beds - 78 of them for general medicine cases and 36 for respiratory medicine.
''Because of the situation where we don't have enough general medicine beds in the hospital for the number of patients we have needing them, we're not getting patients out of the emergency department in time.
We've opened up extra beds in the Acute Services Building which is helping but really we need to be escalating any blocks to patient flow.''
He urged hospital staff to ''play their part'' in moving patients through the system.
''That could mean repatriating people back to rural and regional hospitals or into continuing care in a home-based situation,'' he said.
While unsure of the reasons for the pressure on occupancy rates, Mr Harris queried whether people weren't attempting to see their GP early enough before symptoms worsened.
''It may be that people aren't getting in to see their GP early enough in which case we are reminding the public that unless it is an emergency, get into your GP.''
Medical centres spoken to by Waikato Times indicated they were not seeing any rise on the normal numbers of patients seen at this time of year.