Aotearoa New Zealand’s new national strategy for loosening border restrictions closely follows scientific advice from an expert panel that was specifically asked to advise on the future of New Zealand’s elimination strategy and phased loosening of border controls.
Covid-19 elimination has been the dominant strategy for a number of jurisdictions across the Asia-Pacific region, including New Zealand, China, Hong Kong, Taiwan, Singapore and Australia. This approach contrasts with the suppression and mitigation strategies of Europe and North America.
Elimination relies on strong border controls to prevent importation of Covid-19, often with rigorous quarantine and testing. Several of these Asia-Pacific countries, notably Australia and Singapore, have released “roadmaps” for how they will “open up” their borders. A common feature of these plans is to achieve high vaccination coverage and then transition away from elimination to suppression or mitigation strategies where some circulation of Sars-CoV-2 will be accepted.
The New Zealand plan is different. While it also relies on achieving high vaccination coverage as a key prerequisite for any relaxation of border restrictions, the plan is based on sustaining elimination.
This means that it retains many aspects of the current elimination strategy, including intensive testing and contract tracing and the potential for highly targeted “lockdowns” to stamp out outbreaks from border system failures if necessary.
A central feature of the new plan is a cautious, phased approach to loosening border controls, with piloting of alternatives to facility-based quarantine. As currently envisaged, New Zealand will use a risk-based travel approach where travellers would be divided into three entry pathways based on vaccination status and where they are coming from.
Quarantine-free entry would be allowed only for vaccinated travellers who had been in low-risk countries. Medium-risk travellers would have reduced quarantine, potentially at home. High-risk travellers would continue with 14 days in managed isolation and quarantine (MIQ) facilities. All groups would have pre-travel and post-travel testing, as they largely do now. The extent of quarantine-free entry will be highly dependent on which other countries have been able to suppress or eliminate transmission, which will in turn depend on how the pandemic continues to evolve internationally.
New Zealanders are likely to respond favourably to the announcement that the country will continue to maintain elimination of Covid-19. The strategy is popular with New Zealanders because of the multiple benefits and relative certainty it has offered compared with the alternatives.
This strategy has given the country the lowest Covid-19 mortality in the OECD and supported good economic recovery and low unemployment. It has resulted in very little time spent in lockdown (as reflected in the Oxford Stringency Index), providing New Zealanders with the unusual experience of maintaining near-normality in their daily lives during this global health crisis.
Elimination offers several additional benefits. It buys time before the population is exposed to high levels of the circulating pandemic virus, allowing decision-makers to gain a better understanding of how the virus behaves and how best to control its impacts on population health and wellbeing. New Zealand is closely observing international evidence about the full impact of the virus on children, given the possibility that widespread infection could result in a legacy of long-term health issues, including cognitive impairment.
New Zealand also has the advantage of being able to connect with and support other countries pursuing elimination, in particular Pacific Islands. Two of these are already in a quarantine-free travel zone, notably the Cook Islands and Niue, and others are likely to join soon (for example, Tonga and Vanuatu).
As with all countries, the final-end point for the pandemic and the pandemic response in New Zealand remains uncertain. One optimistic end point is that infection with Sars-CoV-2 becomes more like what is experienced with the relatively benign endemic coronaviruses that cause the common cold. However, there is a range of far more pessimistic scenarios in which continuing high infection rates across the globe generate and select for even more infectious variants that partially escape vaccine-induced and natural immunity and also cause a high burden of chronic illness in some.
By choosing to continue its elimination strategy, New Zealand is keeping its options open and can potentially navigate an optimal path through this uncertain future. At present, the country is choosing not to accept endemic infection as inevitable and is not “learning to live with the virus”.
Instead, it is taking a path that is more aligned to the elimination approach used for polio or measles. Countries across the globe have chosen not to tolerate circulating infection with these two pathogens because the health burden is too high, and it is notable that measles is far more infectious that Covid-19. Even the highly aspirational idea of global eradication of Covid-19 should not be dismissed: on an initial analysis it appears technically feasible.
Whether New Zealand’s approach is successful or not, it will provide useful lessons for other countries in dealing with both this pandemic and other pandemics that are yet to come.
Prof Michael Baker, Dr Amanda Kvalsvig and Prof Nick Wilson are epidemiologists at the University of Otago’s Department of Public Health in Wellington