The Government is considering the role contract tracing may have as part of New Zealand's future COVID-19 response, with daily QR code scans dropping this week to a six-month low.
But while locations of interest are no longer being published and only household contacts are currently required to isolate, experts suggest there is still value in people scanning in.
The latest provisional data from the Ministry of Health shows the number of daily scans fell to about 963,000 on Sunday and then to 945,000 on Monday. That's the first time since September that the daily totals have dropped below a million.
The ministry says figures can increase for up to a month after being reported as the data is uploaded from devices, but there has been a clear downward trend in scanning since December, when more than 3 million daily scans were being regularly recorded.
The number of 'active devices' - those that have either scanned a code or added a manual entry in the last 24 hours - has also fallen significantly.
Dr Andrew Chen, a research fellow with the University of Auckland's Koi Tū: The Centre for Informed Futures, says the numbers aren't surprising but are "a little disappointing to see".
Although the lower number of scans could be put down to more people isolating and therefore not out and about scanning into places, the decision to stop publishing locations of interest has clearly had an impact, he said.
"If you scan a QR code and somebody else gets sick, the way that you get notified that you're at the same place as them is through the locations of interest system, so people aren't getting notified based on their QR code scans right now. That's a pretty good reason to stop doing it."
The ministry ended its usual practice of reporting locations of interest as New Zealand moved to Omicron phase three. That's because of a shift away from contact tracers investigating individual cases' exposure points due to the high number of cases in the community.
Officials are instead now placing focus on vulnerable people and high-risk settings, with most cases asked to complete an online contact tracing form and alert their potentially exposed contacts themselves.
While only household contacts now need to isolate, the ministry says other contacts should still be told "so they can make decisions for themselves".
Dr Chen told Newshub that as scanning in allows the COVID Tracer app to record where you've been, it is an important tool.
"If you do get sick, then you still have a moral imperative to tell the people that you know that you're potentially exposed, that you've got COVID," he said.
"Having some sort of diary will help you be able to go back and figure out where you are and who you are with. Of course, that doesn't help you if you're in a retail shop or something like that, but at least it'll help you get to some people."
Dr Chen said it was positive to see the number of devices with Bluetooth tracing enabled was staying stable at just under 2.5 million.
"That one is passive, so you turn it on and leave it on in the background and you forget about it. Not too many people are going and actively turning that off so they probably do still believe that there is some utility in participating in the system."
What's after the Omicron peak?
Contact tracing and scanning may again become a major part of our COVID-19 response when we hit the other side of the Omicron peak and there are fewer cases, Dr Chen told Newshub.
"If we can get back down to say, hundreds of cases a day, then we may have another shot at suppression or even elimination of the virus. If we do get to that point, we'll all be called to use all of the tools at our disposal again to make sure that we're keeping contact tracing going.
"From that perspective, it can be argued that maintaining your habits is a lot easier than stopping and having to get it back up again."
Director-General of Health Dr Ashley Bloomfield made a similar point to Newshub.
"As we come down off the peak of the Omicron outbreak, we may find that we want to and are able to use our contact tracing system more widely again and quite clearly QR codes are helpful in that regard.
"I think about it a bit like mask-use. Once you're in the habit, just keep doing it. Remember it does provide that record back for 14 days and you never know quite when it is you might need to know. Businesses are still displaying them... so I just encourage people to keep doing it."
Dr Bloomfield said the role of contact tracing after Omicron peaks is under consideration, noting that we could still be seeing "anywhere between 3000 and 5000 cases a day still in New Zealand" for months.
"In that context, it may then be worthwhile, particularly in certain settings, for us to be contact tracing so we would want to make sure that we were able to use our QR code system."
He referenced comments from Scottish Chief Medical Officer Sir Gregor Smith that the virus isn't something to be blasé about, and that it continues to evolve.
"One of the other reasons we might actually want to really engage our contact tracing system again in the future is if there is another variant where it's very important we apply quite rigorous public health approaches to getting on top of it quickly."
Prime Minister Jacinda Ardern this week also said that the Government would be "considering the way contract tracing will be used in the future of our COVID management".
"There are still some high-risk environments - for instance, aged residential care - where you do want to make sure that you have a good understanding and system to be able to contact trace.
"But more broadly, we do need to look at whether or not it's a tool we still need and that's one of the things Cabinet is considering over the next week."
Ardern said she is still scanning in - but one person who isn't is ACT leader David Seymour, who believes there is no point to it anymore.
ACT released a report in February providing a cost-benefit analysis of various COVID-19 public health measures. It was premised on the idea that New Zealand's response to Omicron needs to be different to our response to Delta.
In the paper, the party said that with so many cases, the benefits are limited as contact tracers can't keep up. It acknowledges the costs are "not large, but they are there", mentioning the expense of maintaining contact tracing and compliance costs for businesses.
It advocates for the requirement for businesses to display codes and have people scan in be dropped as well as the requirement to contact trace.
"Contact tracing creates relatively minor costs, but also delivers negligible benefits because it does not reach enough potential contacts or reach them fast enough in light of Omicron’s higher transmissibility."
On Wednesday, the Government revealed tourists will be able to return to New Zealand from mid-April. Seymour said that will shine a light on "how absurd many of our policies are".
"We not seriously going to expect tourists to come and get a New Zealand-compatible vaccine pass, scan in with QR codes with the New Zealand COVID Tracer app, isolate for seven days if they get a positive test and continue to follow all of the rules that we have."
National this week also advocated for scanning requirements for businesses to be dropped.
Dr Chen questions how much compliance costs businesses displaying QR codes, but recognises that may be a "stronger argument on vaccine passes".
"At least give people the option [to scan in]. I don't think we should be getting rid of it."