When it comes to New Zealand’s Covid-19 response, we should be able to think big and consider far-fetched and expensive options in order to avoid more lockdowns, argue Professor Philip Hill, Tony McFall and Professor Kurt Krause
If there is one thing that’s clear to everyone in New Zealand as we move forward into 2022, we all want to avoid lockdowns. We know from the Delta variant of the virus which causes Covid-19 that, along with very high vaccination coverage, we will need various other restrictions to avoid uncontrolled outbreaks.
So, apart from tweaking Alert Levels 1 and 2 and taking advantage of any advances on the vaccine side, what else can we do? Here, we imagine what we call a four-component response to Covid-19 outbreaks, an integrated approach which could be possible based on our understanding of emerging technological advances around the world.
The four components of this ‘next level’ approach are: (1) widespread rapid testing; (2) standard contact tracing; (3) electronically enhanced tracing of otherwise untraceable contacts; and (4) early monoclonal antibody preventive treatment of case contacts. Let’s deal with these components one at a time.
First, widespread rapid testing is possible using advances in testing technologies. Gains have been made with PCR-based methods with the addition of saliva testing to nasopharyngeal swabs, along with pooling of samples so that many more can be processed by laboratories. Rapid antigen tests, which tend to be slightly less accurate than PCR-based methods, are being used in many countries as complementary tests. They can be done at home, have a turnaround time of a few minutes and produce a simple yes/no readout, like a pregnancy test.
We know that only a minority of symptomatic people seek a Covid-19 test in New Zealand. Therefore, tests which are slightly less accurate but encourage a much higher proportion of people to get tested, help negate that issue. Crucial for an effect at that population level is that a high proportion of those with symptoms can easily get tested and case contacts are managed rapidly.
Second, standard contact tracing has advanced considerably in New Zealand. There is standing and surge capacity in public health units, enhanced and standardised connectivity across the country, introduction of an app to facilitate contact tracing, near real-time mathematical modelling, whole genome sequencing, sewage sampling, and performance indicators.
There has been some scenario planning and a limited amount of stress testing of the components of the system. In tandem, wrap around care and supports for cases and contacts have been integrated and teams have improved their Pacific and Māori engagement over time.
As mentioned in previous reports to the Government, one of the key things that is needed is an expansion of the standard contact tracing capacity in New Zealand, so that it does not get overwhelmed by outbreaks. As the borders are reopened, more outbreaks are expected to occur in different parts of the country and the outbreak response capacity in New Zealand needs to be able to cope with that, maintaining high quality throughout the management of each outbreak.
Third, electronically enhanced tracing of normally untraceable contacts could be achieved using cost-effective smart bands, which can participate in the Google Apple Exposure Network (GAEN) deployed via the NZ COVID Tracer App. Turning on bluetooth tracing within the app means close proximity contacts are securely and anonymously recorded; the GAEN smart band allows people without smartphones to participate in the network and record their close contacts with other smart band or smartphone app users.
Some people can’t afford a smartphone or simply don’t have a need for one, such as the elderly or those under age 12. The smart bands are not online and require a smartphone to provide a gateway connection to the ENS. For younger people, this would normally be a parent’s smartphone with the NZ COVID Tracer App. For some groups with less access, a common smartphone could be provided to a household (one smartphone can be the gateway for an unlimited number of smart bands).
When a case is discovered, close contact ‘keys’ are checked by each device and the user is alerted to any potential exposure to an infected person. Widespread deployment of the technology will capture even fleeting contacts, which have been shown to pass on more transmissible variants of the virus.
State of the art smart bands are fully waterproof, display date and time, and have a range of sensors to count steps (pedometer) and monitor health indicators. These features will make the smart bands much more appealing to wear compared to an inanimate object like the Covid Card.
Fourth, recent evidence suggests that laboratory-made monoclonal antibodies, which bind to the key target protein of the virus that causes Covid-19, can help reduce the chances of infection and symptomatic disease in Covid-19 case contacts.
Researchers conducted a randomised trial of subcutaneous administration of 1.2g of a monoclonal antibody combination (made by Regeneron Pharmaceuticals) against the virus in people who were traced within 96 hours of their contact with a case. The treatment decreased the risk of developing symptomatic infection by more than 80 percent. Also, if infection does occur, the treatment lessens its severity and speeds recovery.
This kind of injection would be a perfect tool following exposure within a family group or following unexpected exposure as occurred in Middlemore Hospital in Auckland when one patient in a four-bed ward tested positive for the virus. It would effectively help bring ongoing transmission streams to a halt for known contacts and decrease the chances that any infected contacts need admission to hospital.
Integration of enhanced basic public health practice with high tech diagnostic, digital and molecular biology solutions could form a potent combination to combat Covid-19 outbreaks. If a high proportion of cases are detected early, their contacts are then engaged to protect them and to minimise ongoing spread of the virus through preventive monoclonal antibody treatment. This protects our health system, which will need to be able to carry on looking after all the other health needs of New Zealanders.
This may sound a bit far-fetched and expensive to some. However, when Level 3 or 4 lockdowns cost billions of dollars a week, we should be allowed to think big about the options for avoiding them. One of the great mysteries of the approach to test and trace, so far, is that we have only been investing a few tens of millions of dollars per year into this system. If we can invest many more millions to save billions, while protecting lives, why wouldn’t we?
Professor Philip Hill is a McAuley Professor of International Health in the Department of Preventive and Social Medicine at the University of Otago.
Professor Kurt Krause is a Professor of Biochemistry at the University of Otago.
Tony McFall is an Auckland-based business owner and technologist. His company designs and develops the GAEN Smart Band.