Alternatives to nasal swabs, such as saliva tests, could be cheaper and less invasive. Photo / 123RF
Alternatives to nasal swabs, such as saliva tests, could be cheaper and less invasive. Photo / 123RF
New Zealand authorities are investigating saliva testing for Covid-19 and are in contact with Yale University researchers who developed the process.
Air New Zealand is pushing for surveillance testing of its crew, some of whom face multiple nasopharyngeal swab tests every month, depending on where they fly.
Saliva tests are increasingly being introduced overseas as a less intrusive and cheaper alternative to the nasal test.
A Ministry of Health spokesperson said New Zealand's Covid-19 testing laboratories and ESR were already considering saliva testing and are in communication with the Yale group.
"However, more investigation is needed to ensure the accuracy and viability of any saliva test before it is offered in New Zealand. Information about the cost and processing time for saliva testing is not yet available."
The ministry was "constantly monitoring and reviewing" international Covid-19 research, including new testing developments.
Two new studies out this month have found saliva testing — which requires someone to spit into a receptacle that is then sent for analysis — is about as accurate as nasal swabs.
A Yale School of Public Health study led by Kiwi scientist Dr Anne Wyllie has found saliva samples may detect the virus better than a nasal swab.
The SalivaDirect test has been granted emergency use authorisation by the US Food and Drug Administration.
Not only is it easier, it also removes about 80 to 90 per cent of the cost.
Air New Zealand's chief medical officer, Dr Ben Johnston, said Air NZ crew could face close to 20 tests a month.
"I'm talking daily with aircrew who have had lots of tests and a number of them are getting quite anxious about a test — they find it unpleasant," he said.
Healthcare workers have to carry out the nasopharyngeal tests wearing personal protective equipment and have close contact with the person being tested.
The SalivaDirect test allows people to spit into a jar and then send the sample for analysis.
Johnston said surveillance testing of asymptomatic workers was likely to be required for some time and for those people who were being tested frequently, it was important to make those tests as simple, easy and comfortable as possible.
Saliva tests were used for Air NZ crew when they arrived at Hong Kong but those going there and to Shanghai and Samoa needed a negative nasal swab before departing. They are also tested when they return from layovers in the United States, which the ministry deems high risk.
Other saliva tests are being developed around the world, and in the US, former Food and Drug Administration chief Scott Gottlieb told CNBC that lateral flow tests, which provide a readout on a device like a pregnancy test, could also be coming onto the market there soon.
He said they are popular in other countries, and because they can deliver results in 10 to 15 minutes, could be used to test for the coronavirus in schools and offices.
