Stay at Home poster in Christchurch on day six of the level 4 Covid pandemic Government-ordered lockdown New Zealand country wide.

ANALYSIS: We went hard and we went early, the Government says about its response to the Covid-19 pandemic.

But with nearly every country facing the same challenge – many using measures similar to those enacted by New Zealand – the question is how hard, and how early, did we go?

An analysis of the global response to the pandemic shows that New Zealand moved quickly by any measure, particularly among Western democracies.

Internationally, there are few examples of countries enacting national lockdowns faster than New Zealand; and those that did have faced criticisms of human rights breaches and other heavy-handed actions to contain the virus.

ALVARO CALVO/GETTY A volunteer from the Spanish Red Cross this week. Spain has had a severe Covid-19 outbreak.

New Zealand had one enormous benefit: Time. Many countries missed the window to enact strong physical distancing measures – which evidence shows are a vital tool in fighting the virus – before they could contain its spread. Some countries that, relatively speaking, put in place lockdown measures just days later than New Zealand have failed to limit the virus' spread.

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Experts have warned against comparing the reported infection rates between individual countries, due to the range of factors involved.

Among them are the rate of testing, urban density, the extent of community spread, the age make-up of the population, the resilience of its health system, and even whether it's reporting the numbers accurately.

Covid Trends The rate of growth in confirmed Covid-19 cases in every country, plotted on a logarithmic scale.

What makes New Zealand even less comparable to many other countries is the apparent lack of significant community spread. This means most confirmed cases originated from someone who caught the virus overseas and then returned to New Zealand.

If that holds true, once the length of the lockdown extends past the virus's incubation period – around two weeks – you would expect to see a drop in cases.

What is more comparable – although it, too, requires numerous caveats* – is each country's epidemic curve. Every country has its own curve, which in most cases starts off looking similar, with cases doubling every two or three days.

International data from Johns Hopkins University, plotted on a logarithmic graph at Covid Trends, shows this effect. No matter the country's size, the rate of change in confirmed cases starts off similarly.

Once community transition is in effect, they either flatten the curve, or remain on the same trajectory.

It means that although we can't compare the overall trajectories of any two countries, we can look at what each country was doing at the relative point on their own curve; Were they going hard and early, or soft and late?

COVID TRENDS New Zealand's lockdown versus Italy's lockdown, at their respective points on the epidemic curve.

BEHIND NEW ZEALAND

New Zealand entered its level-four lockdown on March 25, at which point it had 205 confirmed cases of Covid-19.

This was six days after it closed the borders to all non-New Zealand citizens and residents – at that stage, it had 28 confirmed cases.

It can't be overstated how fortunate New Zealand was in still having a small number of confirmed cases by mid-March. Many Western countries reached this stage a week or two earlier, when there was still reluctance to pursue severe physical distancing restrictions.

Italy, for example, reached the point on its epidemic curve where New Zealand locked down on February 24, a full month earlier.

The two countries are no longer comparable, but at the time, Italy was in roughly the same boat as New Zealand; A small number of confirmed cases, mostly from overseas, doubling every two or three days.

Italy didn't put a lockdown in place then. That came weeks later, on March 9, at which point the virus was rampant with nearly 10,000 confirmed cases.

COVID TRENDS New Zealand's lockdown versus Spain's lockdown, at their respective points on the epidemic curve.

Similarly, Spain – another global hotspot – reached 200 cases on its epidemic curve on March 4. It declared a lockdown on March 14, at which point it had nearly 9000 cases.

COVID TRENDS New Zealand's lockdown versus Norway's.

New Zealand entered lockdown, relatively speaking, more than a week before both countries did, largely because it had them as examples of what happens when the virus spreads unabated.

Those countries are also much larger – 200 cases is more proportionally significant in New Zealand than Italy. But even when adjusting for population, New Zealand moved much faster than both

Many other countries were slower than New Zealand, particularly those that had early outbreaks. They include the United Kingdom, Belgium, Ireland, France, Switzerland, Iceland, and the United States.

There were countries similar in size and geography to New Zealand that still lagged its response, albeit not by much, in part because they had a faster increase in confirmed cases.

Norway, a first world democracy with a population similar to New Zealand, recorded its first case of Covid-19 on February 26, two days before New Zealand's first confirmed case.

It enacted a lockdown on March 12, at which point it had 700 positive cases; The equivalent of if New Zealand had enacted its own lockdown three days later than it did.

COVID TRENDS New Zealand's lockdown versus Estonia's lockdown, at their respective points on the epidemic curve.

Data from Norway has been encouraging since it went into lockdown. Three weeks later, its curve has started to flatten, and authorities are confident the infection rate has been reduced.

Another similar country is Denmark, which has a population of just over 5.5m. It reported its first Covid-19 case one day before New Zealand.

It was slower than nearby Norway in putting in place a lockdown, which it did, in part, on March 13, before expanding on March 18, at which point it had 800 and 1100 cases respectively.

Staying in the same neighbourhood, Finland – population also 5.5m – had its first confirmed case nearly a month earlier, in late January.

It imposed a lockdown on March 16, when it had 277 cases, broadly similar to when New Zealand shut down. Its lockdown was less strict, however, allowing many businesses to stay open.

In all cases, New Zealand acted slightly more quickly in the context of its own curve, but did so with the benefit of at least a week in real time.

WITH NEW ZEALAND

That wasn't true in all cases. A small number of countries moved similarly quickly to put lockdowns in place.

One example is Estonia, in eastern Europe. Its population is smaller than New Zealand's, but its daily rate of Covid-19 testing is similar. Estonia declared a state of emergency on March 13, at which point it had 79 confirmed cases: A few days ahead of New Zealand, relatively speaking.

Its lockdown was not quite as strict, however, and allowed some shops to remain open; it has since expanded its restrictions.

Its curve initially showed signs of flattening, but has since returned to its previous rate of growth.

For a country that moved at roughly the same time as New Zealand, with measures similar in scope, we can look at Argentina.

Its lockdown began on March 21, at which point it had 158 confirmed cases; the equivalent of about one day ahead of New Zealand's lockdown.The terms of its lockdown are largely the same as New Zealand's, with only non-essential workers permitted to leave home, except to buy food or medicine.

Its population, of course, is much bigger; about nine-times larger.

For one last example, we can look at the Czech Republic, which has a population double New Zealand's.

It started shutting most businesses on March 12, at which point it had 94 cases, before enacting a full lockdown on March 15, when it had 253 confirmed cases.

AHEAD OF NEW ZEALAND

That leaves the countries that moved more aggressively than New Zealand.

A defining feature, again, is time: Like New Zealand, their first cases came later than many other countries. Another characteristic is they tend to be non-Western, with economies less driven by international tourism.

Among them is Paraguay, in Central America. Its first confirmed case came on March 7, about one week after New Zealand.

It had social distancing measures in place quickly: From March 10, it restricted public gatherings and by March 20, had enacted a full national lockdown. At that stage, it had just 18 cases, with only one linked to community transition; its case numbers have slowly risen to 77.

COVID TRENDS New Zealand's lockdown versus Morocco's lockdown, at their respective points on the epidemic curve.

Its extreme response has been criticised, with accusations of brutality at the hands of local police enforcing the lockdown.

Similarly, Kenya also enacted strict measures early on its curve. It closed all schools, banned public gatherings, and closed the borders to non-Kenyans on March 15, two days after its first confirmed case. It expanded its restrictions to a national curfew by March 25.

As of Thursday, the country had 81 confirmed cases. Like Paraguay, there have been criticisms of heavy-handedness among police enforcing the curfew.

Morocco, in North Africa, had its first confirmed case on March 2. It began restricting entry to the country from March 13, ramping up to a full lockdown on March 20, at which point it had 77 confirmed cases.

It, too, has been criticised for authoritarian elements in its response, namely arresting people for spreading "fake news" about the pandemic.

Even further along the curve are those countries with the most time, many of which are in the Pacific Islands.

The likes of Papua New Guinea and Fiji have enacted lockdowns with barely a handful of cases between them, effectively before the curve has even begun.

While there are some examples of countries moving faster to impose lockdowns than New Zealand, they sometimes came with concerning enforcement measures.

Among countries similar to New Zealand, it went about as quickly as any other in the western world, largely with the benefit of time. Nevertheless, it is accurate to say New Zealand went hard and went early.

* One difficulty is comparing the lockdown measures between countries, as some are much stricter than others. The use of a logarithmic scale can also be confusing, as it makes large numbers look close to smaller numbers, distorting the severity of countries further up the curve. Nearly all Covid-19 graphs have limitations and should be viewed with that in mind.

FASTER THAN NEW ZEALAND

Paraguay

Kenya

Morocco

Bolivia

Lithuania

Jordan

SIMILAR TO NEW ZEALAND

Argentina

Czech Republic

Estonia

Norway

Costa Rica

Peru

SLOWER THAN NEW ZEALAND

Italy

Spain

United Kingdom

United States

Germany

France

Iceland

Austria

Australia

Colombia

Brazil