Omicron: ‘Wider use’ of RATs, PCR test capacity increased

Source: 1News

Rapid antigen tests will see “wider use”, but PCR tests will remain the mainstay in the Government’s initial Omicron response, Associate Health Minister Ayesha Verrall says.

Robots have allowed the automation of some tasks in the processing Covid-19 tests.

Verrall announced the Government would be increasing the number of PCR tests the system can process from a maximum of 39,000 tests a day to a baseline of 58,000 tests.

There was also the ability to surge that capacity to 77,600 tests a day, which could be kept up for a week, she said.

“A rapid rise in case numbers will require us to shift from identifying all infected individuals to being more targeted to those most at risk and those needed to maintain critical infrastructure,” she said.

“Nasopharyngeal PCR tests will continue to be used as the primary diagnostic test in our initial phase of dealing with Omicron in the community, but this will be supplemented by wider use of rapid antigen testing (RAT).”

In October last year, the Government was criticised by both experts and the opposition for its relative “slowness” in preparing for the use of rapid antigen and saliva tests.

Verrall said the Government had made a number of improvements since then.

This included installing robots in labs that automated aspects like de-capping test samples, Verrall said.

She said this would free up more lab technicians and eliminate the risk of mistakes with repetitive tasks.

Saliva tests had also been introduced to 4000 border and MIQ workers, Verrall said.

New Zealand businesses were also allowed to import, distribute, supply, or sell approved types of rapid antigen tests to “authorised” people, which included businesses for use among staff and unvaccinated domestic travellers, she said.

She said the number of types of RATs approved for import had also doubled, and criteria for them had been revised to make it easier for new products to undergo a full assessment.

“We will continue to approve more [RATs] throughout this week.”

However, National's Covid-19 response spokesperson Chris Bishop accused the Government of "hiding incompetence" by "seizing" supplies after being too slow to order RATs.

“I have been approached by a series of organisations today, all of whom have orders for rapid antigen tests about to be filled. They have been told that those orders cannot be filled because the rapid antigen tests are now going to the Government instead," Bishop said.

“That the Government has now resorted to requisitioning rapid antigen tests from the private sector is a stunning indictment of the Government’s incompetence over rapid antigen testing."

The Government largely stopped the importation of RATs for most of last year, citing the importance of accurate testing for its elimination strategy. It only loosened importation rules for businesses in late 2021.

Prime Minister Jacinda Ardern said on Tuesday the country had 4.6 million RATs already in the country, with a confirmed delivery of an additional 14.6m over the next five weeks.

Work was underway to get another 22m over the same period.

RATs tend to be less sensitive than the PCR method when detecting Covid-19 cases. Sensitivity describes the proportion of people with the virus who return a positive result.

That lack of sensitivity is particularly apparent when testing people who are asymptomatic or those who are either very early in or towards the end of their infectious period, when they have less of the virus in their bodies. That’s because rapid antigen testing looks for the protein of the Covid-19 virus, rather than its RNA genome.

What antigen testing lacks in sensitivity, however, it makes up for in speed. Because the process doesn’t require samples to be sent to a lab, it can be done in as little as 15 minutes.