The Hawke's Bay District Health Board is urging the public to refrain from turning up at coronavirus test centres without GP referral.
The Community Based Assessment Centre (CBAC), Covid-19 dedicated testing sites, require patients to first phone their GP for approval prior to arrival.
The CBACs use a drive through system, in which patients are met by team members who assess them and instruct patients on what they need to do.
Hawke's Bay DHB emergency response operations lead Claire Caddie said people can only be tested at CBACs if they have a referral from their GP.
"They are not drop-in centres," she said. "If you are ill, you must phone your general practice first.
"Your doctor will take a full history of your illness and, based on that, will be able to tell you whether you need Covid-19 testing, or whether you need other treatment.
"The teams can only test for Covid-19. The risk is that patients with other respiratory ailments, not related to Covid-19, will not get the right treatment if they do not phone their GP first," Caddie said.
The first Hawke's Bay CBAC is in full operation in Hastings, with further centres being set up in Napier, Flaxmere and Camberley.
Not following the GP referral system may risk patients not receiving treatment they need, according to Hawke's Bay DHB, while having too many people trying to access CBACs could result in overcrowding.
"Our general practice doctors have access to the latest information on the symptoms that mean someone requires testing. For your own health, you must phone you doctor's general practice and talk to them first," Caddie said.
Health leaders in Wairoa and Central Hawke's Bay are also advising the DHB on how their communities can be best catered for.
The DHB are urging patients to first phone their GP or the Healthline on 0800 358 5453.