Tracing people's movements as we enter lower emergency alert levels is going to be key to help keep on top of the spread of coronavirus, a leading academic says.
University of Otago Professor Michael Baker also told Mike Hosking on Newstalk ZB that while he was happy with the lowering number of cases, he didn't believe we had "eliminated" the virus from our shores.
In the interview with Hosking, Baker was asked about people's phones being monitored to track their movements whether with an app or another method.
Baker said he would like to see the introduction of a digital app or digital "card".
"So maybe contacts you don't even know that you've had and it means that if you become a case that information can be downloaded and those people will get a text or other contact and told you've been in contact with a case and you need to look at self-isolation for a period if you've been checked out if you have symptoms."
When asked by Hosking the point of considering it, given how well the country was doing, Baker said it wasn't time to be complacent.
"This is a very infectious virus, countries overseas who have got to this point have unfortunately often had large outbreaks subsequently so this is getting us to the point where we can open those borders a bit more, get back to more normal life but the trade off with that is that you have to be incredibly vigilant and you have to have all these systems in place."
As for the usefulness of it if it's voluntary, Baker said the problem with an app is that they would need more than 50 per cent of people using it to get an idea of what's going on and he believed that was a "very high bar".
"The trouble with the app is you have to have very high coverage, probably 50 per cent or more people will have to have it installed and being using it and I think that's a very high bar.
"It's very difficult because some people don't have a mobile phone. There is talk of a card which may be very effective in terms of getting high coverage."
As for what he expected case numbers over the next week, Baker said that was the big unknown.
"Well that's the unknown and that's why in some ways it's a bit too early to say that we've achieved elimination. We've achieved low levels of infection but at the moment with this high level of lockdown we're in, transmission of everything is hugely suppressed in New Zealand.
"The real challenge is as we move ahead into potentially level 2 and beyond, we might see change in transmission recurring and that's why we have to be super vigilant at this point."
He said South Korea had a long period of doing well then it had a large outbreak of 4000 cases in 2 weeks which was why we needed to remain cautious.
He would like to see the country in the same level of transmission as at the moment, or less, for us to move down to level 2. There would also need to be the same pattern of minimal community infection.