Coronavirus: How's New Zealand doing per capita? And is that a fair way to compare us?

Being a small country, New Zealand loves to compare itself to others on a per capita basis.

We're never going to top the Olympic Games medal table, but when ranked medals-per-person, we usually do well - coming fourth at both Rio and London, and seventh at Beijing. 

Much has been made internationally of New Zealand's success at controlling the spread of COVID-19. The vertical axis on the widely-shared Financial Times' daily graphs of new infections had to be adjusted because ours trended down so fast, we literally fell off the bottom of the chart. 

But how are we doing per capita? And is it fair to compare our success to other nations that way?

First, the numbers. As of Thursday, April 23, New Zealand had 1451 cases and 16 deaths. That works out to: 

  • a case fatality ratio of just over 1 percent
  • 301 confirmed infections per million people
  • and three deaths per million. 

This places us 77th in the world for highest infection rate out of the 211 countries being tracked by data website Worldometer. We're slightly below the world average of 337 infections per million however.

As for deaths, we're ranked alongside alongside China, Australia, Lebanon, Qatar and a few other countries. Worldwide so far it's killed 23 in every million people - more than seven times the rate we've had here.

Australia, whose lockdown has been famously looser than ours, has - per capita - recorded slightly fewer infections and the same number of deaths as us. The USA, where health officials have struggled with protests against lockdown measures and a President who's constantly played down the threat, has recorded 2553 infections and 143 deaths per million. The UK, which locked down late compared to most other Western nations, has recorded 1966 infections and 267 deaths per million.

The virus has hit Europe and the US particularly hard - both wealthy economies - while it's yet to hit poorer regions like sub-Saharan Africa and the Indian subcontinent in any significant way, according to official figures. India for example has recorded only 15 cases and 0.5 deaths per million people, despite the virus' highly infectious nature.

There is wide acceptance now however in countries which have struggled to contain the virus, many more people are infected than the official statistics show.

Epidemiologist Simon Thornley of University of Auckland told Newshub comparing different countries' death rates per capita is a "very questionable" way of measuring the success of each nation's response to the pandemic.

"The test for COVID-19 is quite a sophisticated test, and only wealthier countries can afford it. It would be useful to at the very least only compare countries that have similar rates of per capita testing for the virus."

As noted above, wealthier countries have recorded much higher per capita infection rates for the virus behind COVID-19 than the poor. And even among wealthy European nations, Dr Thornley notes there is a 10-fold difference between them, which is "likely to be due mainly due to testing capability".

University of Otago public health specialist Nick Wilson said comparing death rates per capita is "only a very approximate guide", agreeing with Dr Thornley that the availability of testing kits would also likely influence whether a death was counted as being due to COVID-19 or not.

"Also the age-structure of the population in each country differs - countries with a greater proportion of the elderly will tend to have higher death rates (given that older people when infected have a higher risk of death)."

Dr Thornley also pointed out each country would have its own criteria for listing a death as being due to COVID-19. 

"At present anyone who tests positive for COVID-19 and dies soon after is labelled as a COVID death."

The Ministry of Health told Newshub every person who tests positive for the virus before or after death, or is considered a "probable case" is counted in New Zealand's official total.

"We are not currently separating out deaths with COVID-19 versus deaths from COVID-19," a spokesperson said.

France, the UK and China - where the virus originated - all recently revised their death tolls up significantly after taking a closer look at what was happening. France and the UK realised many deaths happening outside hospitals weren't being recorded, and China said many deaths which took place in the pandemic's early weeks were missed in the confusion.

Italy, which has been hit hard by the virus, has also likely had far more deaths to COVID-19 than its official total of 25,085. Researchers who looked at the overall death rate in Nembro, a small town in Italy's hard-hit Lombardy, found four times as many people have been dying as usual. Nearly 160 died in the first four months of 2020, compared to an average of 35, suggesting the official Nembro COVID-19 death toll of 31 was well below the true figure. 

Sir David Skegg, an epidemiologist acting as a special adviser to Parliament's Epidemic Response Committee, recently said he believed the virus - which can spread asymptomatically - was far wider spread than our testing showed. He declined to comment to Newshub for this story. 

Director-General of Health Ashley Bloomfield earlier this month said New Zealand had "a much better idea than [other countries] have of the total number of cases".

"I think there's agreement around the world that where you see what appears to be a disproportionately high number of deaths compared with the overall case numbers, it's very clear they're not finding all the cases."

San Marino, which has one of the highest GDPs per capita in the world, also has the highest number of cases and deaths per million - it only has 33,000 people, but has recorded 488 cases and 40 deaths. 

But for a disease as infectious as COVID-19, it wouldn't take long to spread through the entire population of a small nation like San Marino, potentially leading it to have a higher death rate per capita than a large country, whose true toll might not be known for a long time.

"If comparing prevalence of cancer between countries, you'd adjust per capita, because it's not a transmissible disease: it comes from lifestyle, genes, pure chance, so if per-capita rate is higher in A than B, that's because of something happening in that country," Financial Times data specialist John Burn-Murdoch tweeted.

"COVID spreads from person to person; it's not like cancer... Generally, and especially early in outbreak (first few weeks), higher per-capita numbers just mean smaller country, not anything different about how that country's dealing with COVID."

In terms of deaths per million as of this point in the pandemic, San Marino is followed by Belgium, Andorra, Spain, Italy, France, the UK, the Netherlands, Switzerland and Sweden - all wealthy nations. 

The World Health Organization on Thursday warned even as the curve flattens in hard-hit wealthy nations, the pandemic is far from over.

"Most countries are still in the early stages of their epidemics. And some that were affected early in the pandemic are now starting to see a resurgence in cases," said Director-General Dr Tedros Adhanom Ghebreyesus.

"Make no mistake: we have a long way to go. This virus will be with us for a long time."