Coronavirus: Massive jump in tests amid demands for more and questions over data from the Ministry of Health

A drive-through testing clinic in the United States. Photo / AP

Our testing for Covid-19 has massively escalated in recent days with almost half the total number of scientific checks for the virus carried out in one day this week.

Yet there are signs it is taking days to return tests in provincial New Zealand even though they only take a matter of hours to process, even as the National Party has spoken out to demand more testing be done.

There has also been apparently contradictory information out of the Ministry of Health over how many tests have been done.

The Ministry of Health has told the Herald there had been 1002 tests carried out on Wednesday which brought the total number of tests carried out to 2363.

Just hours later, Director-General of Health Ashley Bloomfield said during his public briefing the 1002 tests were carried out on Thursday, and provided numbers purporting to show more than 2300 people had been tested over just three days.

Bloomfield's briefing didn't align with the Ministry's earlier statement, or with its running tally over the course of the crisis. Requests for clarification to the Ministry of Health have gone unanswered.

National's health spokesman Michael Woodhouse said he was concerned there was not clearer information being made public about the exact number of tests, testing capacity, stockpiles of testing equipment, or those who had recovered from the virus.

He said New Zealand needed to know how many testing kits were available and how long we could test people at a rate of 1500-a-day - the presumed maximum capacity of labs.

"For weeks it has been too hard to get tested. You have to go on Healthline for hours, are then told to contact a doctor and you need to have both symptoms and close contact to meet the criteria."

He said testing should have been more frequent and widespread, and needed to take into account research showing those without symptoms could be carriers and that a negative test didn't always mean someone wasn't infected.

Woodhouse said he would like to see the 150 Dunedin schoolchildren tested this week to go through another round of testing next week.

"South Korea has shown how testing can get this virus under control and the World Health Organisation is saying 'test, test, test'. Getting New Zealanders tested is the most important job the Minister (of Health David Clark) has right now.

Minister of Health David Clark is facing criticism from the National Party for not testing widely. Photo / Mark Mitchell

"We are following the pattern of every other country that has had a sustained community outbreak. Why would we be any different?"

The 1002 tests carried out either on Wednesday - according to the Ministry - or Thursday - according to Bloomfield - were just shy of New Zealand's current capacity of 1128 tests a day.

It appeared to be a huge increase with Ministry of Health data showing 366 tests carried out in New Zealand between March 7 and March 17.

On March 7, there had been 218 tests completed - 11 days on from the first identified coronavirus case arriving in New Zealand.

By March 17 - according to Ministry of Health information - the number of tests completed was 584.

The accelerated testing regime matches an increase in cases, with New Zealand now having 39 people to have tested positive for Covid-19. More than half that number have tested positive in the past week.

The Herald has been told there are 30,000 test kits available which contain two swabs with just one swab usually needed, creating the possibility of effectively doubling the stockpile.

Bloomfield said today there was no shortage of testing kits as community testing centre began opening up across the country.

"Tests are not being rationed," he said during his daily press conference. Instead, he said, they were being targeted where they were best used.

"We don't have a shortage of swabs at the moment," he said. "We're just making sure we can have both the swabs and other supplies needed to keep testing the people who need to be tested."

The Herald also understands the tests are not foolproof with about 20 per cent returning negative tests on those who carry the virus.

University of Auckland molecular medicine and pathology associate professor Mark Thomas confirmed the testing kits would not always return a positive test for someone carrying the virus.

He said he had been told by colleagues in Australia of a case which had returned five negative tests before returning a positive result for the virus.

Thomas said the process for testing involved collecting genetic material from snot, saliva or sputum that had been coughed up from lungs.

He said the sputum was the best material to use when searching for the genetic identification that marked out coronavirus. It wasn't always possible to collect sputum if the sufferer had a dry cough, meaning alternative and less effective samples would be sought.

Thomas said the sample was processed in a sophisticated laboratory that was able to separate the virus and monitor how it multiplied. The speed with which it did so would reveal how much of the virus was present in the host.

"It can tell you how infectious the person is likely to be. People with more virus tend to get more sick."

He said the test could be completed in hours, meaning it was possible for a sample taken in the morning to return a result in the afternoon.

Director General of Health Ashley Bloomfield's daily briefings on coronavirus have kept the country informed. Photo / Mark Mitchell

Thomas said he understood the scale of tests able to be carried out in New Zealand was expanding, with Middlemore and North Shore hospitals joining Auckland hospital's laboratory in processing result. He said he understood the private lab company Labtests would also be joining the effort.

He said it was not expected there would be a problem with supply of the testing kits, with the possibility of manufacturing replacements in Auckland.

Thomas said there was no dodging the coronavirus but New Zealand needed to aim at managing its impact in the way Hong Kong, Singapore and Taiwan had done. He said Australia should be watched as a guide to where New Zealand would go, with similar responses in each country.

"They are perhaps a week ahead of us."

Australia currently has 709 cases of the virus, with the 144 latest cases emerging over 24 hours. Six people have died. Australia's population at 24.7m is five times the size of New Zealand's at 4.8m.

Despite the test taking only hours to complete, some communities have been kept waiting for days.

In Northland, the Kerikeri community spent three anxious days waiting for test results to come back for a student visiting from Thailand.

The child had arrived at the school on Monday, fallen ill on Tuesday and was tested that afternoon for Covid-19.

The school wasn't able to tell its community until this morning that the test had come back negative.

In the days of waiting, attendance at the school and the neighbouring primary plummeted as concerned parents kept their children at home.

Testing in New Zealand falls behind that carried out in most of the world, when measured by tests conducted per million people, but our exposure to the virus is also delayed.

Australia has done more than 3000 tests per million people, Italy around 2500 and the United Kingdom about 750.

New Zealand has tested around 500 people per million citizens.