Some Aucklanders are waiting four to five days to find out their Covid test results as the system strains under mass testing being undertaken across the country.
Prime Minister Jacinda Ardern said more than 100,000 tests had now been taken in Auckland alone as the Delta outbreak spreads in the nation's biggest city and in Wellington.
With 107 confirmed community cases, health teams have further identified more than 14,000 contacts - most considered close contacts - and over 400 locations of interest.
The scale of the outbreak means health teams are likely ensuring they return test results faster for those with close links to the outbreak, experts say.
The Herald has sought comment from the ministry about test wait times.
Director general of health Dr Ashley Bloomfield earlier said a temporary IT outage affecting testing registration software Eclair had played a part in causing delays.
But it is also mainly in Auckland and at GP clinics and places that did not use the main testing system where the longest delays in getting results back were occuring, he said.
Despite that, there are still more tests being processed more quickly than in the last outbreak, Bloomfield said.
Widespread testing and knowing where Covid is being spread remain the key to getting ahead of the outbreak and ending lockdown.
And while experts acknowledge the testing system is always under increased strain in the days after an outbreak as people rush to be tested, University of Otago professor of public health Nick Wilson said results should be coming back faster.
"We've been seeing the Delta variant at play in the world for quite a few months now - at least six months.
"So maybe we should have been using the last six months to build up testing capacity."
As well as building up laboratory processing capacity, Wilson called for a greater roll-out of wastewater and saliva testing.
He said while government-backed science research group ESR has done a great job boosting wastewater testing to include 41 sites, the testing should be done more frequently.
"A lot of those sites are still on just twice weekly, ideally they should be daily.
"The international evidence is you can detect one infected case in 30,000 people, up to being able to detect even one case in 300,000 people."
Wastewater testing had the ability to potentially alert authorities to a positive community case before even the infected person knew they had could Covid.
That is because people can start excreting the virus before they start showing symptoms or go to get a Covid test, Wilson said.
It could play a key part in judging certain parts of the country, such as the South Island, to be virus-free and able to move down to less strict alert levels.
That was because wastewater testing could not only pick up the virus in human faeces but also if infected people take showers or wash their clothes.
"If someone is just excreting respiratory virus and coughing on to their hands, when they have a shower that virus will be washed off through the system and be detected," Wilson said.
"Similarly, if they cough on to their elbow into their clothes, when the clothes are washed that virus particle will also go through the wastewater system and be detectable.
"So this is the time to really ratchet up wastewater testing to a very high level."
Wilson also wants to see saliva testing rolled out more widely.
A saliva PCR test, allowing people to simply provide a saliva sample, is far less invasive than the nasopharyngeal PCR test uncomfortably taken through a person's nose.
Wilson said even if it didn't help speed up processing in laboratories, saliva testing could help speed up testing queues, free up medical staff because it required less training to administer and encourage more people to be tested because it was not uncomfortable.
It was also revealed last month that the Ministry of Health wanted to implement daily saliva testing in quarantine facilities as far back as January this year - but it remains infrequently used.
There are conflicting views on whether it is sensitive enough to become the main form of testing.
The ministry has been facing criticism - which it rejects - that it has been the main obstacle to rolling out the testing in MIQ facilities because of the technical advice it has given to Covid-19 Response Minister Chris Hipkins that saliva testing is not reliable enough.