ESR researchers test wastewater samples from managed isolation facilities. The agency is exploring whether wastewater stations could provide community-level surveillance. Photo / Dom Thomas/RNZ
ESR researchers test wastewater samples from managed isolation facilities. The agency is exploring whether wastewater stations could provide community-level surveillance. Photo / Dom Thomas/RNZ
Science agency ESR is pushing closer towards new types of tests that rapidly reveal whether someone has Covid-19 - or how widely the virus is circulating in a community.
In an extended interview with the Herald, ESR's new chief executive Peter Lennox said his staff were actively looking at saliva tests, along with serology or antibody tests.
Saliva tests could prove more sensitive and effective, and less invasive, than the nasal swabs Kiwis are used to.
New Zealand scientists have already suggested border workers could be excellent candidates to use rapid and minimally invasive techniques, such as the SalviaDirect method developed by Nathan Grubaugh and Anne Wyllie at Yale University in the US.
That could mean staff who work at managed isolation and quarantine facilities to submit a saliva sample each day, or every few days, along with routine temperature checks and health questionnaires.
Recently given emergency use authorisation by the US Food and Drug Administration (FDA), SalivaDirect was well suited for groups of people who needed repeated testing.
"New Zealand's Covid-19 testing laboratories and ESR are already considering saliva testing and are in communication with various groups, such as the Yale School of Public Health," Lennox said.
"However, more investigation is needed to ensure the accuracy and viability of any saliva test before it is offered in New Zealand."
Serology tests, meanwhile, were blood tests that could show if a person may have once had been infected without knowing, revealing hidden chains in outbreaks with mystery sources.
They had the potential to identify those who were infected within a few minutes, allowing them to self-isolate and avoid infecting others.
ESR boss Peter Lennox says more investigation is needed before rapid saliva tests for Covid-19 can be used in New Zealand. Photo / Supplied
"These are becoming more important as the pandemic progresses and we look to find those people who have had the disease but didn't know they were ill," Lennox said.
"There are many such tests and understanding the value of various test options will be important in knowing how they can best be applied.
"ESR has been evaluating several tests. Additionally, we are awaiting ethics around a study in the serology area, so keep your eyes peeled for this."
Another area being further explored by ESR was the potential for wastewater stations to be used for community-level surveillance of Covid-19.
"The message here is our team is going strong on this research project, but it is very much a research project, and it is taking place over 18 months," Lennox said.
"The main message is that the research is progressing but the data from the collection of samples are not yet actionable.
"But we are working with the Ministry of Health to feed any intelligence from the research in an appropriate way and looking at where we can deploy our limited resources within the research."
A machine sorts positive Covid-19 samples for genome testing at ESR's Porirua testing facility. Photo / Dom Thomas/RNZ
For example, he said, If the monitoring turned up any positive results, that would be passed along to the ministry, with caveats about the use of these data.
"The overall goal long-term is for robust and reliable tools for the detection of SARS-CoV-2 in sewage, that can be used to identify any unrecognised Covid-19 infections in New Zealand," he said.
"We also want to gauge how infectious it is in sewage and the persistence of SARS-CoV-2 in sewage."
But before that could be done, a proper methodology needed to be developed.
"As part of method validation work and following the cluster of new cases in the community, wastewater samples are now being collected from other Auckland locations, and from a range of other regions in New Zealand and being sent to ESR for analysis."
ESR has been playing a leading role in New Zealand's public health response to Covid-19, processing thousands of tests to date, and sequencing, or decoding, genomes from more than 850 positive samples - 93 of which came from the August Auckland cluster.
"When the pandemic hit, ESR was quick to see what more investment was needed in this area with the purchase of new equipment," Lennox said.
