A New Zealand science tech company is talking to the Government about using immunity testing as part of the mix in the planned risk-based border opening strategy. But Delta means it’s very much a moving feast, writes Nikki Mandow. 

Professor David Williams is one of those super-clever, super-understated scientists you want on your side in a pandemic.

The sort of person who can explain complicated stuff in a way a layperson can understand. But someone whose research career – including almost 300 peer-reviewed articles in international journals on anything from electrochemistry and trace gas sensor technology, to biomolecules and nanoparticles – is pretty extraordinary.

He’s also an entrepreneur. He’s someone who revels in taking science out of the lab and making a business out of it. He’s listed as the inventor on around 50 patents and has founded several businesses, including air pollution monitoring company Aeroqual, and real-time data measurement and crunching firm Mote Ltd.

Back in the day he worked for the UK-based company that developed the ClearBlue home pregnancy test. 

But the project that’s taking up most of Williams’ time at the moment is Orbis Diagnostics, a company developing Covid-19 antibody/immunity testing technology. 

David Williams is one of the Auckland University scientists behind Orbis Diagnostics. Photo: Supplied

Williams is chief scientist and vice president of product development at Orbis and one of the brains behind its ‘lab-in-a-box’ testing machine, which is designed for use at the border, particularly at airports.

The technology will be capable of taking a tiny blood sample from up to 15 people at a time, spinning the drops of blood around fast with a chemical reagent and 15 minutes later coming up with a reading for the level of Covid immunity someone has.

At the most basic, the test could check that someone’s vaccination certificate is valid – a low antibody count could indicate a forged certificate. 

At the other end of the scale, a high antibody count could give border officials confidence the person coming in has good immunity – either because they’ve recovered from the virus or have been fully vaccinated.

The key to the Orbis machine is a spinning disc which holds the blood samples and mixes them with a reagent. Photo: Supplied

The trouble with vaccinations, as we know too well from the present Delta outbreak, is getting a jab is not necessarily enough, because not everyone gets good immunity from the vaccination. 

The Orbis Diagnostics test gives an indication of how an individual person’s body has reacted to the vaccination, Williams says. Have they developed lots of antibodies – which might indicate a stronger immune response or a greater level of immunity. Or have they got a lower antibody count – which might mean they are a greater risk to others.

“The risk varies according to the level of response you have had to the vaccine,” he says.

A recent paper published in the journal Nature and coming out of research from the prestigious Sydney-based infectious diseases research centre, the Kirby Institute, found the early immune response in a person who has been vaccinated for Covid-19 can predict the level of protection they will have to the virus over time. 

“Neutralising antibody levels [could be used] as a ‘proxy’ for immune protection from Covid-19,” the authors found.

Reopening strategy

At the moment, with the borders pretty much closed and everyone who arrives in the country going into 14 days mandated quarantine, there’s little point knowing what someone’s immunity level is.

But the Government has said that at some stage it will start reopening the borders. Last month, following the report of the Strategic Covid-19 Public Health Advisory Group led by Professor Sir David Skegg on reconnecting New Zealand and ironically, just the week before we all went back into Level 4 lockdown, Prime Minister Jacinda Ardern talked about implementing a tiered, risk-based system for people coming into New Zealand, possibly early in 2022. 

Covid-19 Response Minister Chris Hipkins gave more details

“The group recommends a phased approach to slowly admitting more travellers to New Zealand, without needing to go into MIQ, based on risk-based factors such as their vaccination status and the state of the pandemic in their country of origin,” he said.

“These travellers would still be subject to a number of requirements, such as proof of vaccination, pre-departure testing and rapid testing on arrival in New Zealand,” Hipkins said.

That last point is what the team at Orbis Diagnostics is talking to the Government about – adding on-the-spot immunity testing into the mix at the border.

“Some people have been vaccinated, but that doesn’t mean to say they’re low-risk. So what you want to know is how people have responded to the vaccine. And the stronger the response to the vaccine, the lower the risk,” Williams says

A part of the risk mix

New Zealand businesses are hanging out for a situation where fully vaccinated people coming in from low- or medium-risk countries could have a less onerous MIQ experience. 

Self-isolation at home, perhaps, or a shorter stay in a managed facility. 

Following the announcement of a limited trial for business people from larger organisations being able to travel overseas for work and then do their 14-day quarantine period at home, there has been a rush of companies wanting to sign up.

The trial would involve “hundreds of people, not thousands”, the Prime Minister said, and would take place between October and December. 

As well as being a life-saver for businesses trying to get workers in and out of the country, allowing some people to isolate at home or shortening their stay in MIQ could also free up places in managed isolation, thereby relieving some of the backlog for other returning New Zealanders. 

It could even signal a gradual restart of overseas tourism.

But each time someone comes into the country there’s a risk they bring Covid into the community. That risk will increase when the Government relaxes restrictions – as they will have to do at some stage.

Immunity testing should be part of the mix trying to keep that risk to a minimum, Williams says. At the very least because it’s guaranteed that some people are going to forge vaccination certificates, he says. But also because of the way different people react differently to the vaccination, and because of the likelihood that the effectiveness of the vaccine will wear off over time.

“Antibody testing isn’t the only answer but it is something that’s different and that adds another layer of protection and decision and might enable you to shorten that period in isolation,” Williams says.

“What’s now known is you can measure antibody concentrations, and you can correlate that to the risk of infection. Because everybody’s immune response is different.”

Ministry of Health chief science advisor Dr Ian Town says the ministry is monitoring new testing technologies with interest.

“The issue of antibody testing is being closely looked at within the wider Reconnecting New Zealand work currently being undertaken across the Government. We are looking at how antibody testing may fit into this programme,” Town says.

“The ministry’s newly established Covid Testing Technical Advisory Group will consider the role of [antibody] testing as part of this work.”

Delta changes the playing field

No one’s saying it’s easy. The thinking from the Government about opening up, thinking that led to the announcements about the home isolation trial and potential MIQ relaxations, have been thrown into question by Delta.

And not just in New Zealand

A plan by the Hong Kong government to let fully vaccinated people from medium-risk countries with a positive antibody test to spend just one week in hotel quarantine, not two, was scrapped last month after officials got cold feet over the Delta variant.

Media reports said the Hong Kong decision was triggered by the case of a fully vaccinated Hong Kong woman who tested positive for Delta after completing her seven-day hotel quarantine, despite having passed the antibody test.

“We do not want to reverse our decisions on a frequent basis,” Hong Kong chief executive Carrie Lam told local media. “But sometimes we have to err on the side of caution in order to prevent the spread of the disease.”

October trials 

Meanwhile, Williams says the first commercial prototypes of the Orbis immunity testing technology are ready, with the machine being built in the US, and the “consumables” – the discs and other parts needed to do each test – being made in New Zealand. 

A planned pilot study to obtain data has been delayed by the lockdown, Williams said, but should start in October. If it can’t go ahead in New Zealand, there are other countries interested in a trial, he says.

In January, Orbis announced a deal with multi-billion-dollar French biometrics and digital identity firm Idemia, to roll out the technology into airports around the world, once it’s been developed. 

But it’s not been easy, or cheap.

Even as someone who has commercialised science before, developing the antibody testing technology has been “surprisingly expensive”, Williams says. Trying to build a complex piece of equipment with all the Covid-related supply chain and travel restrictions has also been challenging.

David Williams, pictured with chief technical officer Dr Matheus Vargas. Photo: Supplied

“The number of glitches, you know, it’s like hacking your way through hawthorn bushes. But we’ve got a machete so away we go.” 

Orbis first started looking at testing for Covid immunity back in 2020, but the spinning disc technology has been under development for at least five years before that – beginning with a summer project for University of Auckland students.

“Airports and milking sheds have got a lot in common. The queues of animals or people waiting to go through control gates.”
– David Williams, Orbis

At that time, the testing technology was being developed to test cow’s milk for progesterone levels to monitor when an individual cow was ready to get pregnant. (Progesterone levels change at a time when the cow is getting more fertile). 

But testing cows daily in a milking shed environment needed a particularly sturdy piece of equipment with the capacity to churn out lots of tests, relatively cheaply, and providing fast results. 

Pivoting to work on providing robust, fast, not-too-expensive blood tests at an airport wasn’t too big a jump, Williams says.

“Airports and milking sheds have got a lot in common. The queues of animals or people waiting to go through control gates.”

Measuring declining immunity over time

Opening up the borders isn’t the only potential application for the antibody testing device. It could also be used to do regular testing for people in high-risk occupations – air crew, for example, or border workers – to make sure their vaccine-induced immunity isn’t wearing off, Williams says. 

The Kirby Institute paper suggests “immunity to Covid-19 from vaccination will wane significantly within a year, with the level of neutralising antibodies in the blood dropping over the first few months following infection or vaccination”.

And antibody immune levels are much easier to measure than vaccine efficacy over time, the authors say.

Williams says this could be a key use of the Orbis technology.

“If immunity fades over time, how do these people know whether they are still safe from getting really sick from Covid? The answer is you test them. And if their antibody count has gone down then you know to give them a booster.

This way you don’t have to give boosters to everyone, just the people who need it, Williams says.

“You could do this test every month or every couple of months and you’re giving reassurance to the people doing these jobs. And you’re giving reassurance to the public as well.”

Nikki Mandow was Newsroom's business editor and the 2021 Voyager Media Awards Business Journalist of the Year @NikkiMandow.

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