The latest in our series of charts, graphics and data visualisations by Chris McDowall. David Garcia helped create today’s charts.

This work is entirely funded by the generosity of The Spinoff Members

These posts collate the most recent statistics and present them as charts and maps. The Ministry of Health typically publishes data updates in the early afternoon, which describe the situation at 9am on the day of release. These data visualisations are interactive – use your mouse or thumb to hover over each graph for more detail.

Note for users of The Spinoff app: if the charts below are not appearing, please update your app to the latest version.

This afternoon’s Ministry of Health figures report that the total number of confirmed and probable Covid-19 cases stands at 1,386 (1,078 confirmed and 308 probable). A total of 728 people have recovered, an increase of 100 since yesterday. There were six new confirmed cases reported in the last 24 hours and 14 new probable cases. No further deaths have been reported.

The number of significant clusters with 10 or more cases increased by one to 16. There are 13 people in hospital, which is two fewer than yesterday. There are now three people in intensive care units – one each in Middlemore, Dunedin and North Shore hospitals. The Dunedin patient remains in a critical condition. The person in North Shore hospital is freshly reported to be in a critical condition.

This chart compares active and recovered cases. Active cases are confirmed or probable cases of Covid-19 where the person has neither recovered nor died. Recovered cases are people who were once an active case, but are at least 10 days since onset and have not exhibited any symptoms for 48 hours.

For the first time, the statistics show more recovered than active cases. The number of active cases dropped again, from 729 to 649 this morning. The downward trend that started around April 8 continues.

Yesterday, 2,100 tests were processed. This is a more than during the Easter period, but still below last week’s totals, which ranged between 3,500 and 4,500. The ministry reported averaging 2,761 Covid-19 lab tests per day during the week ending April 14. A total of 66,499 lab tests have been conducted since January 22. There are 71,693 test supplies in stock, up from 70,826 yesterday.

The symbol map shows confirmed and probable Covid-19 cases arranged by district health board. In keeping with the relatively small number of new cases, there is minimal change in regional counts. Southern (213), Waitematā (201), Auckland (182) and Waikato (179) remain the four district health boards with the largest number of active cases. The largest increase in cases were in Canterbury, up five to 144, and Counties Manukau, up four to 107.

There are 16 significant clusters under investigation by the Ministry of Health, an increase of one overnight. A significant Covid-19 cluster is when there are 10 or more cases connected through transmission and who are not all part of the same household. The cluster count includes both confirmed and probable cases.

The new cluster is an aged residential care facility in Auckland, where the number of cases doubled from five to ten overnight.

This chart shows cases according to their original “date of report” rather than the “date the case was classified as confirmed/probable”. This is a subtle but important distinction as there is sometimes a lag between a “potential” case getting updated to “probable” or “confirmed”, yet the date of report stays the same.

The same broad trend that we see in the other charts is evident here. There is a downward trend in the number of cases. Even with a few potential cases getting upgraded to probable or confirmed in recent days, these numbers look promising.

Note that the number of cases reported on a particular date may not match the number of cases reported in the last 24 hours. This is because the number of confirmed and probable cases reported in the last 24 hours includes cases which were entered on an earlier date as “under investigation” or “suspected” whose status has now been changed to confirmed or probable.

According to a group of academics, the New Zealand response doesn’t match the threat posed by Covid-19 and should be substantially loosened. Siouxsie Wiles unpicks their claims.

A group of six New Zealand academics yesterday announced their “vision for a balanced response” to the Covid-19 pandemic. They are calling that vision “Plan B”. They even have a website and a PR firm attached. They are clearly serious.

Their plan is for New Zealand to return “to normality as soon as possible” by moving to something like alert level two. They want most people to be able to get back to work, for schools and universities to open, and for people to be able to travel around the country again.

And the reason they are advocating this plan? Because, they say, “international health data and experience is showing that New Zealand’s lockdown may now be unnecessary, and even more harmful than the problem we’re trying to solve.”

That’s a big statement. It’s an important statement. So let’s look at how their evidence stacks up.

Claim 1: the risks of the virus have been overstated

They present several stats and statements to back up this claim, so we’ll take each one in turn.

“With over 1,300 confirmed and probable cases and four deaths, the overall CFR in New Zealand is approximately 0.30%. … This overall CFR rate is similar to that seen for seasonal flu epidemics and indicates that the virus poses a low risk of fatality to the vast majority of people.”

CFR stands for case fatality rate and it’s a pretty unreliable number in the middle of an outbreak. Saying that, it’s still being widely used, and current estimates put it somewhere between 1% and 5% for China, Canada, Germany and Switzerland, rising to around 10% for Italy, Spain, UK, France, and the Netherlands. On the one hand the CFR depends on how cases and deaths are classified, and this is being done differently in different countries. Some countries are only testing people with severe disease in hospital. Others are testing as many people as possible, including those without symptoms. And some countries are only counting deaths that happen in hospital in people who have tested positive for Covid-19. This likely means that many deaths are being missed. Evidence for this is coming to light by looking at the number of overall deaths different countries are experiencing compared to the same time over the last few years when they weren’t in the midst of a pandemic.

Other things that can influence the CFR are the age and health of the people getting ill – we know that older people and those with underlying health issues are more likely to die. So if most of the cases are in young and more healthy people then the CFR will be lower. The other thing that will be impacting on the CFR is whether health systems are overwhelmed and unable to provide the care that very ill people need.

And lastly, as Spinoff cartoonist Toby Morris and I pointed out recently, it can also take some weeks for people to die from Covid-19. Here in New Zealand that means we need to prepare ourselves for more deaths. Yesterday, just hours after the Plan B academics released their new commentary, four new deaths were announced. It brings our total to date to nine. And almost doubled our CFR.

“An analysis by Professor David Spiegelhalter at Cambridge University shows that the CFR from the disease is conservatively estimated to be about the same as an individual’s average annual fatality rate … If you catch Covid-19 your likelihood of dying is the same as your average likelihood of dying that year anyway.”

They are using this to argue that the people who have died would probably have died regardless. They say it is “likely that some of these deaths were with the virus rather than a direct result of infection”. Note how they emphasise the word with. No less than Professor Spiegelhalter himself has declared that this is a complete misunderstanding of the point he was trying to make.

“No deaths have yet occurred in people under the age of 70.”

Because of the lag in how long it can take some people to die, this statement is basically meaningless at the moment. It is important, too, to point out that plenty of young, healthy people have died from Covid-19 around the world, including many healthcare workers. There is nothing about New Zealand that makes us magically different.

Claim 2: Clearly, up to now, the virus has not had the devastating effect on hospital services as it was thought to

This is completely misleading. The reason Covid-19 hasn’t had a devastating effect is because we went into lockdown. If we hadn’t gone into lockdown, cases would have continued to grow exponentially and the same thing that has happened to hospitals in other countries would have happened to ours. I’m reminded of a quote from Peter De Jager about the Millennium Bug: “We’re damned if we do and damned if we don’t here. If there are no problems, then people say, well, there was never an issue.” In other words, we are a victim of our own success. But the difference with this pandemic is that we just need to look around at what is happening overseas to see just how profoundly, painfully worse things could have played out for us. Look at Italy. Look at Spain. Look at Britain. Look at New York City, where there has been an upsurge in mass burials.

Claim 3: Evidence from Australia indicates it is safe to move to a situation similar to alert level two at the end of the four-week lockdown period

Interestingly this group has moved to using Australia as an exemplar of how to deal with Covid-19, instead of Sweden, which a fortnight ago was hailed as “steering a more sensible course through this turbulent time”. Presumably because cases and deaths there are now increasing at an alarming rate, Sweden is not mentioned at all on the new Plan B website.

As for Australia, it’s not quite clear to me what evidence they are using to support the move to level two, given the Plan B website simply points to the Australian government’s emergency response plan.

It’s probably worth noting that different states have been making their own decisions about how to deal with the virus, and usually ahead of government announcements. New South Wales, the state with the highest numbers of cases (2,870) and deaths (26) went into a version of level three lockdown on March 22 and what we could probably call level four lite on March 29. Many businesses are closed, though there hasn’t been a formal closure of schools or universities. Saying that, many schools have shut as parents decide to keep their children at home and universities have shifted to online learning.

It all comes down to what we value

According to Plan B, so that the rest of us can get back to some kind of normal life “people at high risk of severe complications … should continue to self-isolate and maintain social distance”. The idea that this is feasible, never mind desirable, does perhaps depend on whether you fall into the “high risk” category.

It’s worth pointing out, too, that this is the strategy the British government started out with: lockdowns for the vulnerable, while everyone else carries on as normal. They were hoping to maintain this until they could reach herd immunity – which is the strategy implicit in the Plan B argument, though they don’t refer to it as such. Boris Johnson introduced the strategy by telling the British public that everyone should “expect to lose loved ones before their time”.

The UK has since changed course, and is now on a lockdown that looks very similar to ours. Only with thousands of people dead, including plenty who wouldn’t have been classed as vulnerable. In other words, “allowing the population to develop immunity, which is a natural defense for the virus after infection could occur, and manage the spread of the virus while protecting those most vulnerable from the disease” [sic] hasn’t worked in the UK. So why would it work here? Plan B and the herd immunity strategy reminds me of a line by Lord Farquaad from the movie Shrek: “Some of you may die, but that is a sacrifice I am willing to make.”

This type of argument plays into a “health versus economy” fallacy, too. Of course the public health experts advocating the lockdown strategy understand that it brings serious and real harm to the economy, and that doing so has an impact on the health and wellbeing of people. Those considerations are baked into the thinking. But this is a matter of the least-worst. Again, you just need to look abroad to see how very much worse off we could be.

The level four lockdown has been stressful and difficult for so many people. What’s important now is that we don’t lose the advantage we’ve gained from doing it. If we exit too early and too quickly, any cases of the virus will begin to grow exponentially again. We can’t let that happen. Instead we need to be confident that we can stop the virus using the tools we currently have – testing, contact tracing, and isolation. Because everyone living in New Zealand has the right to a meaningful quality of life, not just those who are young and healthy.