New Zealand needs to be able to contact trace up to 1,000 cases of Covid-19 - in case of a large outbreak in the next two years.
That is among the recommendations in a new report into contact tracing by Dr Ayesha Verrall, who found as we went into lockdown Public Health Units were being overwhelmed by less than 100 cases a day.
Dr Ayesha Verrall told Checkpoint the main weakness in contact tracing discovered in her audit was the scale that could be achieved.
"Covid-19 can cause outbreaks so quickly, where case numbers rise exponentially.
"Very good contact tracing occurs in public health units by experienced professionals there, but they also need to be better supported by good data systems. Until we have that we can't really have the assurance we need about the timeliness and the completeness of the process."
The ideal time to trace a contact needs to happen within three days, Dr Verrall said.
"I did the audit a week ago, the capacity had increased since the time we went into lockdown... And it continues to increase all the time.
"I don't have an updated figure on the number of cases we can trace at the moment but I think the scale of the government's announcement is in the right ballpark for achieving this target," she said.
At the time of the audit in early April different public health units had different systems for contacts, and the Ministry of Health's national hub service had not yet been rolled out, Dr Verrall said.
She told Checkpoint the quality of the contact tracing service is high, "it's just the scalability that's the issue, and I suspect as of a week ago we're probably at about 30 percent of where we need to be... to be resilient to an outbreak."
She is not comfortable about New Zealand moving to lockdown level 3 with the contact tracing system as it has been, but she said there are improvements being made every day.
"The government appears to be putting a lot of resource into it and they've accepted the recommendations in my report, so in that case yes, I would be [comfortable with improved contact tracing].
"At the time I wrote my report it wasn't clear what level 3 would look like, but level 3 also has quite a few restrictions in it and the bubble size remains quite small for many people, so I think on that basis it does seem reasonable to continue the work they're doing.
"And they have worked very very fast, to stand up this national service, so I find those things reassuring."
