Covid 19 coronavirus: Compliance checks on isolating close contacts now occurring daily

Close contacts of Covid-infected people are now being checked on every day to ensure compliance and see if they have developed any symptoms, Health Minister David Clark says.

But an app to complement contact-tracing work was still being worked on, and is yet to be released for voluntary registration.

Clark released an update today in improvements to contact tracing, a crucial element in containing any Covid-19 outbreaks particularly when the country is in a less restrictive alert level.

Contact tracing has been considered an area that has needed significant improvement; the release of Cabinet advice yesterday revealed the system could only trace 10 active cases in mid-March at a time when there were 13 cases in New Zealand.

Last month the Health Ministry asked University of Otago infectious diseases physician Dr Ayesha Verrall to audit the contact-tracing regime, and she made several recommendations after finding that regional public health units (PHUs)were overrun.

Verrall was invited back to report on progress last week, and today Clark released her update as well as a response from director-general of health Ashley Bloomfield.

University of Otago infectious diseases specialist Dr Ayesha Verrall says she is pleased to see contact-tracing capacity at public health units increase. Photo / Supplied

Clark said five of the eight recommendations in Verrall's audit had been completed or were now "business as usual", including increasing the capacity of PBUs and contacting close contacts in quarantine everyday to check on compliance and symptoms.

The ministry was still working on some recommendations that would provide a clearer picture of the success of contact tracing.

They include a record of the number of close contacts who have been infected by the time they are contacted, which reflects timeliness, and the proportion of contacts who became infected, which measures secondary transmission.

The latter measurement is only possible at the moment for those PBUs that have adopted the national information system.

That was still being progressed, Bloomfield said.

"Initial focus will be on those PHUs who have no or limited information technology tools to support contact tracing work," he said in his response letter.

"We believe the value in having this national end-to-end view available to all those involved in contact tracing will quickly become clear to those using the system."

Verrall had recommended capacity to trace the contacts of 1000 cases a day, and she believes that needed to be reached before moving to level 2.

But Bloomfield has called into question the basis for this number.

Director-general of health Ashley Bloomfield says the Health Ministry has made "very promising" improvements in contact tracing. Photo / Mark Mitchell

The current capacity of the PBUs is to trace 185 cases a day, with capacity being built to be able to handle up to 300 cases a day.

This week, the Health Ministry published performance metrics for the first time.

From April 18 to 20, it had taken 10 days to isolate 80 per cent of close contacts from the first onset of symptoms from the source of a Covid-19 chain of transmission (the index case).

That has now been halved to five days, and Bloomfield said the ministry wanted to make it four days in line with the benchmark performance in Verrall's audit.

The latest data published by the Ministry of Health shows:

• 80 per cent of close contacts are being isolated within two days of a positive lab result.
• 70 per cent of people are being tested within 48 hours of their first symptom.
• 70 per cent of test results are returned within 24 hours of a swab.

These measures are for 270 contacts for 75 cases over the past two weeks of level 4 lockdown - April 13 to 27.

An independent contact-tracing assurance committee, led by Sir Brian Roche, was appointed last week to oversee how to best implement the recommendations.

"Good progress has been made to date and we will seek to strengthen whatever is required, recognising that the issues at play are broader than just health - they impact on how we will all ensure each other's personal safety and wellbeing," Roche said in a statement.

"Dr Verrall has said we need to contact more people, more quickly. That's why we have already added more staff to the PHUs and the NCCS. That's also why we're progressing with a tracing app."

The app is expected to be released for voluntary registration soon.

Prime Minister Jacinda Ardern has said the app does not need to be up and running before the country can move to alert level 2.

Cabinet will make a decision about moving alert levels on Monday.