Update: This article was first published on February 15. On March 1, the US Federal Drug Administration authorised nationwide use of the University of Illinois saliva test.
Corporates are signing up for a privately-provided high-frequency saliva test for Covid-19, with government testing services unable to meet the capacity demands of more frequent testing.
On January 22, Covid Response Minister Chris Hipkins announced voluntary daily saliva tests for workers at quarantine facilities – first Auckland’s Jet Park, and then dual-use Managed Isolation and Quarantine facilities in Wellington and Christchurch.
But just as they got off the ground at Jet Park, they were stopped so the Ministry of Health could focus resources on an outbreak centred at the Pullman Hotel facility in Auckland. Stopping the saliva testing was “due to the need to concentrate efforts on testing at the Pullman managed isolation facility”, a Ministry of Health spokesperson said.
The delayed testing finally got properly underway in February, the Ministry said – more than a fortnight late. As the Ministry testing programme struggled to cope with higher demand, three organisations had already pushed ahead with privately-provided saliva tests, including Auckland Airport.
Mary-Liz Tuck, the airport’s general manager of corporate services, said they were co-funding the deployment and had set up a dedicated space for testing. Airport staff taking part in the saliva tests were doing so on a voluntary basis and the saliva tests did not replace the nasal-swab testing required by the Government’s border policies.
“All efforts should be made to introduce saliva testing as soon as possible as part of the range of testing methods being conducted … While sensitivity of saliva testing may be slightly less than the current method, the ability to test more frequently and with greater acceptance, may far outweigh that.”
– Simpson-Roche report
“We want to see as many protective layers as possible for our people and our community,” said Tuck. “Developing saliva testing is one way we can make sure New Zealand’s response to Covid-19 is constantly evolving. It will mean we can have more frequent surveillance testing – and that means a better chance of catching positive cases early before they reach the infectious stage, reducing the risk of community transmission.”
The private provider is Rako Science, founded by business partners Dr Stephen Grice, Leon Grice from the US-NZ Business Council, and Hawke’s Bay-based entrepreneur Sean Colgan. They have licensed the University of Illinois SHIELD saliva test protocol, which has already rolled out to millions of people since being validated in America in July 2020. (Update: On March 1, the US Federal Drug Administration authorised its nationwide use).
Air NZ is another company that is inviting staff to volunteer for non-invasive Rako Science saliva tests, a spokesperson said. It has also been working with the government’s Environmental Science and Research lab on a voluntary saliva testing trial, which was meant to start this week – but as with the Ministry of Health saliva tests at the quarantine facilities, that has been delayed.
Despite the widespread international use of saliva tests – their proponents say are quicker, less invasive and more reliable than nasal swabs – New Zealand has been slow on the uptake.
In November last year, the Simpson-Roche report into New Zealand’s Covid response said the Government had taken too long. “Many other jurisdictions internationally are relying on saliva tests for the bulk of their surveillance,” the report found.
“While work is underway in New Zealand on verifying such testing, on current plans widespread introduction is still more than two months off, even though in other jurisdictions saliva testing, involving large numbers of test per day, has been well established for several months.
“The New Zealand time frame appears to be driven by a presumption that saliva test would replace the PCR test. This need not be so, as it could well be complementary.
“All efforts should be made to introduce saliva testing as soon as possible as part of the range of testing methods being conducted. If necessary outside assistance should be sought to accelerate development. While sensitivity of saliva testing may be slightly less than the current method, the ability to test more frequently and with greater acceptance, may far outweigh that.”
“The [saliva] tests are less invasive. They could mean we pick up any positive cases among workers at quarantine facilities faster and will provide workers with another layer of assurance.”
– Chris Hipkins
Two months later, Hipkins announced the deployment of saliva tests in the quarantine facilities, saying they would operate as an additional screening tool alongside nasal swabs, for the country’s highest risk border workers.
“The tests are less invasive,” he acknowledged. “They could mean we pick up any positive cases among workers at quarantine facilities faster and will provide workers with another layer of assurance.”
But that hasn’t happened and meanwhile, Rako Science has quietly deployed its testing in three Auckland organisations. In an announcement scheduled before the latest south Auckland outbreak. the company tells Newsroom it already has capacity to run 10,000 tests a day. Rako has offered its services to the Ministry of Health, but officials chose to rely on the over-stretched ESR labs instead.
At Auckland Airport, Mary-Liz Tuck said they wanted to support a programme that would make asymptomatic testing simple and comfortable for airport and border workers, while providing the highest standard of protection for the community. “Since the outbreak of Covid-19, we’ve been working hard to protect our people and our community from the virus. In real terms, that means thousands of nasal swabs have been taken from our employees,” she said.
“We’re supporting Rako Science’s efforts to deploy a highly accurate saliva test because we know less-invasive, asymptomatic testing reduces the risks of outbreaks.”
How does a saliva test work?
It took some people longer than others to produce a sample, said Rako Science boss Leon Grice. Some got “performance anxiety”, so there were evocative photos in the booths, to get the juices flowing.
That’s photos of food, of course.
With eight booths in each testing station, Rako Science take one sample a minute on average – so long as people drool on demand.
At Auckland Airport, Grice said 10 to 20 people a day had volunteered to do saliva tests over the past four weeks, in a three-month pilot operation run following the Illinois test’s accreditation in New Zealand in December 2020.
“The Rako Science test that we use for saliva is as accurate, if not better, than the nasal swap tests. It has a really low limit of detection.”
– Dr Janet Pitman
The non-invasive test uses one millilitre of saliva drooled into a disposable spoon, which the worker then tips into a QR-coded vial as the sample for rt-qPCR testing. The sample is then heated to 95C, which kills any Covid virus meaning the sample can safely be handled by non-medical staff. Rako speeds the tests from the airport and its two other collection facilities, across Auckland to the IGENZ lab in Parnell which is contracted to test the samples.
According to the University of Illinois, its saliva test has a specificity of 99.8 to 99.9 percent, with very few false positives. “High specificity combined with frequent testing makes the SHIELD saliva-based test extremely accurate,” the University says.
Dr Janet Pitman, the Victoria University of Wellington Te Herenga Waka scientist who validated the Illinois test for New Zealand, confirmed that. “One of the big advantages of the Rako Science test is that it is incredibly accurate,” she said.
“There is a lot of information out there about saliva testing, and some say it’s inaccurate and some say it’s accurate. What’s important to remember is that every single test is different – they all use different kits and they all use different methodology.
“The Rako Science test that we use for saliva is as accurate, if not better, than the nasal swap tests. It has a really low limit of detection.”
“There’s no shortage of need for asymptomatic workforce testing. Even when vaccines come in, we’ll still have a susceptible population. The vaccines will be delivered only to a minority of the population at first, and indications are some people can still be susceptible even after being vaccinated.”
– Leon Grice
Leon Grice said the company provided the Ministry with additional data confirmed the test was as accurate as tests using nasal swabs, just a few days before Hipkins announced plans for ESR to run saliva tests for the quarantine facilities.
Rako could contract labs in other centres as required, to rapidly deploy nationwide, Grice said. The high-frequent testing would be especially useful to frontline agencies and to primary produce exporters, who wanted to assure trading partners that workers handling their frozen food were Covid-free.
“There’s no shortage of need for asymptomatic workforce testing,” he said. “Even when vaccines come in, we’ll still have a susceptible population. The vaccines will be delivered only to a minority of the population at first, and indications are some people can still be susceptible even after being vaccinated.”
If a worker gives their sample before 2pm, Rako promises to return a result the same day, by SMS message. If they do their sample after 2pm, they promise to deliver a result the following morning – offering the potential, Grice said, that saliva tests could be used instead of nasal swabs for outbound international travellers.
The University of Illinois says its test is provided for US$20-$30 per sample, compared to US$100-plus for a standard nasal swab test. Grice was coy about the pricing in New Zealand, saying it was about $40 to $50 but could be cheaper for bigger companies, because of economies of scale. He said it worked out about 80 percent cheaper than nasal swabs.
