The decision to relax the rules for who gets Covid-19 testing is forcing one District Health Board to try to stem the number of people without symptoms turning up.

Photo: Patrick Pleul / dpa-Zentralbild / ZB / AFP

The government wants more testing done - officials say the daily average of more than 1800 tests is just under half of capacity - and, this week, said those with a respiratory illness but who had not been overseas or had any contact with travellers should be swabbed.

That has caused a new set of problems, with doctors worrying the new definition for who could be swabbed will trigger an unsustainable flood.

A GP based in Palmerston North, Dr Huw Jones, said testing centres are already at full capacity.

"There's definitely discrepancies between the prime inister's message and then the message that we get on the ground."

MidCentral District Health Board is worried about the new guidelines too, according to an urgent advisory that Palmerston North public health body THINK Hauora sent out yesterday, and which RNZ has obtained.

"The message from government ... has spurred an escalation in people self-presenting for testing at our designated testing centres, at times in the absence of any symptoms," it said.

"Our capacity to test is pressured and there are risks that our capacity will be exceeded. That includes the testing centres ability to process requests when the numbers staffing these are limited and cannot be easily expanded through primary care resource alone."

THINK Hauora said it would also struggle to keep people at a safe distance from one another if there were large crowds.

The public health organisation said until it received further guidance from the Ministry of Health it, along with the MidCentral DHB, would be restricting tests to patients who made an appointment over the phone first.

Dr Jones said his patients have already struggled with contacting the DHB, with five yesterday being referred to its phoneline but receiving no answer and having no opportunity to leave a message.

Further south, Dunedin doctor Daniel Pettigrew welcomed the widened testing definition but said they were facing the same problems with testing capacity.

If you have symptoms of the coronavirus, call the NZ Covid-19 Healthline on 0800 358 5453 (+64 9 358 5453 for international SIMs) or call your GP - don't show up at a medical centre

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