Microbiologists advising the Ministry of Health saidthere was a shortage in the global and New Zealand markets and have come up with backup plans.
The Ministry of Health said there were 44,000 testing kits in the country, enough to last 15 days at the current testing rate.
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The kits are made up of reagent chemicals - primers, probes and buffers - in addition to either a nasal or back-of-the-throat swab.
The reagents produce the chemical reaction which tells the lab if a result is positive or negative.
In New Zealand, most laboratories use proprietary - that is, branded - models because they have a higher throughput.
However, they require specific kinds of reagents imported from Europe and the US - without them, they do not work.
Clinical microbiologist James Ussher is advising the Ministry of Health's diagnostic working group and said they discovered limitations around the proprietary models a few weeks ago, specifically around their reagents and consumables like cartridges and testing plates.
"Most the laboratories are using proprietary platforms for testing either for the extraction of nucleic acids from samples or for the actual testing platform itself.
"Those are often coming from large multinational companies supplying to many other parts of the world, and demand for reagents far outstrips their ability to supply," Dr Ussher said.
There were concerns around the robustness of manufacturing and supply, Dr Ussher said, with a shortage of proprietary reagents and global demands disrupting the supply chain.
He said labs were often waiting for reagents that were running out which usually arrived in time - or nearly in time.
New Zealand needed to be prepared for other countries and large global players to keep hold of their stock.
"Because things are in global supply, companies are doing the best to try and supply and maintain testing capability in laboratories around the world," Dr Ussher said.
"They're often not able to send out as much as we might like.
Another clinical microbiologist on the team, Joanne Stanton, was working on another backup plan, looking for people who could make the generic reagents and consumables in New Zealand.
She said they were things the country had not typically produced in the past.
"We are posing that hypothetical question, how much of that testing stream that reagent mix could we supply purely from internal New Zealand sources?
"We're actually looking at 'can we make the little enzymes' and it looks like we can.
"We're going through that process of finding out who those people are, do they have the resources, is all the resources they need in country already? So we're asking those questions."
Dr Stanton said they had identified a number of potential local sources which could produce the critical components needed, but she was still looking for more people who could help.
