The pressure of having to look after an influx of tourists is leaving some rural doctor's practices without a GP for hours on end.
In an emergency, doctors have to abandon the patients at their practices to go out to help.
They are worried that will happen more often as tourist numbers increase - and they will not have any extra support.
Nestled near Aoraki-Mt Cook in the Mackenzie District is the rural town of Twizel. It has a population of fewer than 1500 but it swells dramatically during the summer months as tourists descend.
Rural General Practice Network chief executive Dalton Kelly said in an emergency the doctor might have to go out with an ambulance or by themselves.
"What that means is that the people who normally would be going to see the doctor in their practice or the nurse, they won't have access to that person.
"They may sit there for five to six hours not able to see their GP. But the tourist will be well looked after in bad circumstances."
He said at the height of the tourist season a rural doctor or nurse could undertake up to six air ambulance call-outs in a single day.
Staffing remained an issue for many rural practices with Mr Kelly saying a quarter of all rural practices were trying to hire a GP.
He welcomed regional development funding for tourist infrastructure but he said medical services should not be forgotten.
"People coming here for a holiday, they will be more concerned or will want to know that there is a health service that can deliver what they might require if they have an emergency while they're enjoying New Zealand in a rural setting," Mr Kelly said.
"I think health services are more important than carparking and toilets."
However, he did not want to take away from the regional development fund.
Instead he has called on the government to offer additional funding - ideally between $2 million to $3m more to support rural practices.
Tim Malloy is a doctor based out of Wellsford, Auckland's northernmost town.
In summer the town's population swells by 30,000.
Doctors avoided taking holidays during the busy summer period to keep up with the demand, Dr Malloy said.
"We are recruiting internationally for health providers targeting the summer months to ensure that our workforce is at its strength for the demand that the summer represents to us."
The Ministry of Health's community and ambulance manager Andrew Inder said the government required district health boards to respond to the changing demands of their communities.
St John also prepared for the influx of more visitors during the year, Mr Inder said.
"We see them putting additional services in place in Central Otago during the ski season, into places like Twizel during the summer season and they also respond to other national challenges like New Year's."
In a statement, Tourism Industry Aotearoa chief executive Chris Roberts said GPs received more income if they were busier.
"The issue for some rural practices is they can't attract staff. It is a staffing issue, not a visitor issue.
"Most visitors to New Zealand have travel insurance and are charged for any medical services they receive."