New Zealand joined 48 other countries affected by the novel coronavirus last week when health authorities confirmed the first COVID-19 case. The news prompted panic buying of supplies in some places, but it had long been expected.

The management of the case seemed exemplary. Shortly after arriving in New Zealand from Iran, the person became unwell, rang the national health information service (Healthline) and was directed to a hospital where they were placed in isolation. Family members and fellow passengers on the flight were tracked and placed into home quarantine.

As yet, there is no evidence of transmission to others and New Zealand remains at the “keep it out” stage of its pandemic plan.

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Preventing a pandemic

Like many countries, New Zealand has two broad phases in responding to an emerging pandemic: the containment phase followed by the management phase.

The containment phase aims to prevent, or more likely delay, the arrival of a pandemic. New Zealand is managing this by excluding some travellers entirely (currently from China and Iran, except New Zealand residents and their families). It also requires those arriving from a growing list of countries to “self-isolate” for 14 days to reduce the risk of infecting others if they develop disease. Such quarantine is unsupervised, but travellers are encouraged to register with Healthline.

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Border controls make intuitive sense for limiting the movement of infectious diseases between countries. There is evidence they delay the entry of pandemic diseases, and they have sometimes prevented the spread of pandemics to islands. Travel restrictions are not generally supported by the World Health Organization, but it offers no advice specific to islands or for extremely severe pandemics.

If a case of COVID-19 is detected during this containment phase, efforts are made to “stamp it out” by isolating the person and placing their contacts under quarantine. Such measures were effective in ending the SARS epidemic, but are probably unlikely to do more than delay the more infectious COVID-19.

A COVID-19 pandemic could potentially become one of the greatest public health disaster threats in New Zealand since the 1918 influenza pandemic when 9,000 New Zealanders died.

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Managing a pandemic

The detection of cases that have no known connection to travel typically marks the beginning of community transmission and a shift in focus from eliminating an infection to managing it.

With COVID-19, this stage may arrive quite suddenly. Because most cases are mild, the virus may be transmitted through several generations before being detected, perhaps only when someone develops more severe symptoms and is admitted to hospital. This pattern is called silent transmission. It has been reported in a number of locations for COVID-19, including in the US.

In the management phase, interventions focus on dampening down transmission by encouraging hand washing and cough etiquette, which can be poor even during pandemics. Social distancing (working from home, closing schools etc) is also effective at slowing transmission, at least for influenza pandemics.

During this phase, the focus is also on ensuring health-care services are organised to manage increased demand, particularly for scarce resources such as intensive care, and health-care workers are protected from infection.

Health services are critical for reducing the risk of death during a pandemic. Unfortunately, COVID-19 has a relatively high case fatality risk. Nearly 1% of the infected people on board the Diamond Princess cruise ship have died.

What New Zealand needs to do

New Zealand has many natural and institutional advantages in managing the health and economic threats of a pandemic. Like Australia, New Zealand’s island status and ability to control its borders may buy time to continue pandemic planning. Given the seasonality of other known coronaviruses, the summer timing may provide further protection.

But the pandemic has hit New Zealand at a challenging time for public health. Capacity has been reduced by erosion and fragmentation of responsibilities across several agencies over the past decade or more. New Zealand is emerging from a severe national measles epidemic that had its roots in neglected public health infrastructure that failed to raise immunisation coverage sufficiently to prevent it.

New Zealand has a relatively low score, coming in far behind Australia, on the Global Health Security Index, which assesses pandemic capacity. We hope that an upcoming review of the health and disability sector will propose a major upgrade of public health in New Zealand.

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New Zealand’s response to COVID-19 is driven by the 2017 edition of the influenza pandemic plan. But we should also learn from the experience of other countries.

COVID-19 disease risk is highest for older people and those living with chronic health conditions such as diabetes, chronic respiratory disease and heart disorders. Unfortunately, a pandemic is likely to magnify social and ethnic inequalities through multiple pathways linked to poverty, poorer access to health care and a higher prevalence of chronic health problems.

We should learn from China’s apparent success in containing the pandemic, while at the same time balancing all interventions with a strong focus on human rights.

Here are other measures New Zealand could consider to prepare for this pandemic:

• Start talking about a pandemic, rather than using euphemisms, to make it more real.

• Form a parliamentary group to ensure multi-party engagement with the response. During an election year, it would be distracting for the response to become politicised.

• Follow Australia’s lead and other developed countries and rapidly develop a specific COVID-19 emergency plan.

• Consider measures to protect the most vulnerable populations. One option is “protective sequestration” to prevent spread to certain islands or regions as was achieved in the 1918 flu pandemic. This approach is being rolled out at a country level by Pacific nations, notably Samoa which now has some of the tightest border controls in the world.

• Also consider a “safe haven” policy to protect vulnerable groups such as older people with chronic conditions by temporarily moving them to carefully managed locations (such as aged care facilities) for the duration of the pandemic.

The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.