Covid-19

Covid-19 testing ramps up, new method coming

In a matter of days, New Zealand's Covid-19 testing regime has ramped up production dramatically and new ways to test for the virus are on the way, Marc Daalder reports

On Tuesday, New Zealand tested more people for Covid-19 than it did in the prior 45 days combined, back to when the test first became available in the country.

Director-General of Health Ashley Bloomfield told reporters Wednesday afternoon that 620 tests had been completed the previous day, compared to 522 tests since January 31. This was vindication for experts and the Opposition, who had urged the Government to test more people more quickly. International best practice has indicated testing is the most effective way to counter the spread of Covid-19.

What changed? In part, a handful of criteria were altered to allow for testing of people with symptoms and a possible connection to the virus - contact with a confirmed case or having been overseas - even if they didn't have a fever. It seems unlikely, however, that this tweak was responsible for the more than five-fold increase in testing, day-on-day.

Instead, the Prime Minister's longstanding message to doctors, reemphasised on Tuesday morning, that the criteria were a guideline and they should use their discretion to order tests if they saw fit, seems to have finally filtered down to the level of GPs and DHBs. Expect to see testing ramping up further in the coming days as the country's labs expand their capacity to completing 1500 tests a day.

This isn't the only sea change to be observed in New Zealand's testing regime. Health Minister David Clark said Wednesday morning the Government was rolling out sentinel testing to GPs across the country.

This strategy - which has been effective in curbing Covid-19 overseas - is already used for flu-tracking and prevention in New Zealand. In essence, a handful of GPs selected to create a representative sample of New Zealand in geographic and socioeconomic terms test all patients with flu-like symptoms for influenza and report the results to the Government.

Sentinel testing has allowed the Ministry of Health to observe how and where the flu is spreading and to target public health campaigns accordingly. Now, Clark says, the same doctors conducting sentinel tests for the flu will do so for Covid-19.

"Surveillance testing is being stepped up and that works across the country with people who are in practices that have effectively provided monitoring for our flu season normally," Clark said, using another term for sentinel testing.

"They swab people who come in and ascertain how the flu is spreading across the country each season. They will also be testing for Covid-19 in a routine fashion. That's coming on-stream."

Infectious diseases expert David Murdoch said that this can help detect community transmission we may not be aware of. Murdoch is the Dean of the University of Otago, Christchurch, the co-leader of the Infection Group and a Senior Associate in the Department of International Health at Johns Hopkins School of Public Health.

"The question is: is there other hidden transmission around? In influenza season, there's various general practitioners around the country who have joined up to the sentinel programme," Murdoch said. "At a certain time before the influenza season, they'll test so many people - like the first two people a day - who could be influenza or have a cold. You can pick it up early by having these sites that will test those people."

"What they're doing is just going to flip that over to be testing for the Covid virus. The idea is to pick it up where it might not otherwise be tested for and evade detection."

Read more of Newsroom's Covid-19 coverage here.

Covid-19 is transmitted like the flu. The Ministry of Health recommends that all New Zealanders wash their hands frequently and refrain from touching their face in order to protect themselves and others. Call Healthline on 0800 358 5453 if you have any symptoms and have been to any countries or territories of concern or have been in close contact with someone confirmed with Covid-19.