NZ Govt confirms it won’t test for virus prevalence

Media Statement

8 July 2020

The Government has formally confirmed that it will not use any of the current or future serology tests to assess how widespread the Covid19 disease has been in New Zealand.

In answer to an Official Information Request by the Covid Plan B group, the Director of the COVID-19 Health System Response team in the Ministry of Health said serology tests would underestimate the true level of exposure to Covid-19.

Epidemiologist Simon Thornley says the new policy is the opposite of what was done in 2009 when serology data on low prevalence of swine flu convinced health officials not to take extreme control measures.

“Serology testing will underestimate the true prevalence, but that will be many times more accurate than just guessing from tests of people presenting with symptoms.

“Fear and uncertainty are driven by lack of information. The more we know, the better we can fight disease. It has been the policy in the past, so it’s strange not to do it now.”

Thornley says a consistent picture is emerging that nose tests for Covid-19 are only picking up a small fraction of all cases.

“Antibodies, present in the blood as well as T cell immune responses to the virus are revealing the coronavirus has reached far more people than listed in the daily “cases” statistic.

“That is important because it would reveal the true effectiveness of our protective measures, and the true state of our population immunity to coronavirus.”

In response to the OIA request for data from serology testing, the Government confirmed:

“Currently there are no Ministry sanctioned seroprevalence studies being performed”.

It claimed that this was supported by a letter in the Nature Medicine journal which indicated that one study found variability in individuals; 40% of asymptomatic people became seronegative and 13% of symptomatic people became negative for IgG [An immunoglobulin] as they recovered.

It noted that a study had been undertaken by the Southern DHB, and that “Positive COVID-19 cases from the Southern DHB study will be confirmed on a second assay to increase positive prediction value.” It said “future studies will have to learn from the Southern DHB study and adapt its methodology accordingly.” The Ministry added that there had been blood mononuclear cell collection by the University of Otago which would be used to perform future mediated response testing.

/ends

Contact Simon Thornley 021 299 1752

What the latest science says about New Zealand’s Covid-19 policy

Simon Thornley, Gerhard Sundborn

4 July 2020

With a smattering of new cases emerging from returnees in hotels prompting both sides of the house to double down on our tight quarantine the key question is coming into focus: where does our nation go from here?

Sir Peter Gluckman, Rob Fyfe and Helen Clark have recommended starting to reopen our borders. On the other hand, both Dr Ashley Bloomfield and PM Jacinda Ardern have talked about being prepared for further lockdown-like restrictions, with tight border control. Victoria, a state with similar characteristics to New Zealand, has had a recent spike of cases and has decided to enforce local lockdowns, which is a worrying prospect. Which road is best? To open up or to hunker down? Can science help us with this decision?

The latest information on the virus can help us decide which of the Covid-19 roads is best. Its relevance is underlined by the fact it also helps explain why some of the predictions about the fatalities from the virus in New Zealand were 500 to 3,600 times greater than what is happening.

The assumption until now has been that we were all sitting ducks and that we were — and remain — completely at the mercy of the virus. And that assumption underlies the current anxiety about reopening without an effective vaccine to protect us.

The latest science reveals the battle our bodies have had with this virus —and it indicates we are not as defenseless as we might think. Our blood has two major weapons in the fight against viruses:  B and T cells, which together are called lymphocytes or pus cells. B cells are like missile factories, making antibodies that lock onto free virus in the body. Most tests to see if anyone has been exposed to the virus look for these antibody B cells.

T cells are more like hitmen who destroy host cells already infected with the virus. T cells are less commonly considered in testing for previous exposure. A feature of Covid-19 is that levels of both these cells (lymphocytes) are unusually low in severe cases most likely because they have been working overtime to fight infection.

A recent study out of the Karolinska Institute in Sweden confirms this idea. A team of researchers tested the blood of 203 people, some of whom had had Covid-19 (by genetic test), looking for evidence that the immune system of these subjects had seen the virus. Among healthy blood donors, who had never tested positive for Covid-19, the researchers found that 4/31 (13%) had antibodies but 9/31 (29%) had positive T cell responses to the virus. That indicates that many more people had been exposed to the virus (and not fallen ill) than indicated by B cell tests alone.

In family members of people with Covid-19, 17/28 (60%) had positive antibodies (B cells), but almost all (26/28; 93%) had positive T cell tests. Almost all genetic test positive cases of Covid-19 had both immune markers. Some may debate the importance of the T cell tests and whether they confer immunity. The researchers are guarded, but indicate that such responses are similar to the immune response of vaccines for other viruses.

What relevance does this knowledge have to us here in New Zealand, considering who to let in and out of the border? As indicated above, it explains why modelling of Covid-19 was so staggeringly inaccurate. Many more of us than we ever knew have microscopic missiles and hitmen in our system on our side. This helps explain why the predicted flood of cases to our intensive care wards and hospitals never eventuated. And this helps us be more realistic about the risk posed by the virus.

What else can we learn from this study? A critical question now is how immune is our population? We have previously summarised the rates of Covid-19 antibodies measured in populations around the world ranges from 0.5 to 26%. The Swedish researchers have shown that the proportion of people in the general population who are likely to be protected from Covid-19 is actually about three times the proportion who have Covid-19 antibodies. This would mean that likely protection from the virus is far more widespread than the antibody surveys indicate. In New Zealand, we are still waiting for any results from antibody tests. The media has reported that tests have been carried out but no data is being made available. Surely the results of this study, even if preliminary, are of critical importance?

So, how does this help us address the border question? If we really want to know what our risk is posed by the virus, we need to take a keen interest in our population’s immune status, as the Swedes have done. The findings of the Covid-19 virus in France and Spain well before the ‘official epidemic’ hit means that many of us have likely encountered the virus before without even knowing it.

Now, in many countries, deaths with the virus are waning, even if in some countries, cases are increasing. The lack of large second waves as Europe is progressively opening up gives us some confidence that immunity to the virus is much more widespread than we initially thought. The debate about our supposed exalted status having ‘eliminated’ the virus is becoming less relevant as evidence accumulates that many of us have already seen the virus, become immune and moved on.

Some commentators have highlighted the paradox of being a Covid-free cul-de-sac. It is our view that we need to adjust to living with the virus and accept that further cases are likely to occur. If our level of natural protection is much higher than thought we need to urgently reconsider whether the elimination strategy, its implications for further lockdown, and an unknowable period of continued border closure, is really worth the financial pain it will continue to inflict. And let’s not forget Covid-19 is not entirely unique. We already accept the risks of living with a number of coronaviruses that have similar characteristics to Covid-19, including: HKU1, 229E, OC43 and NL63.

Vaccine researchers say sorry: no vaccine in time to make a difference

The implications of this statement by vaccine researchers are profound.

They say that a vaccine for Covid19 won’t be found in time to make a difference to the natural outcome of the pandemic.

So is NZ still planning to wait?

 

It typically takes a minimum of 10 years for a vaccine to complete the three consecutive phases of the clinical research pipeline. This is because of the scope and length of the experiments, the need to critically assess the results at each stage and the mountains of paperwork that are involved.

 

We contend that a safe and effective vaccine against severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), which is the causative agent of coronavirus disease COVID-19, most likely cannot be made available to the public in time to make a substantial difference to the natural outcome of this pandemic. People often cling to hope even when prospects of success are low. However, this can have negative consequences if that hope is not realized.

 

https://theconversation.com/fast-covid-19-vaccine-timelines-are-unrealistic-and-put-the-integrity-of-scientists-at-risk-139824

Why new Covid19 cases is not a “surge”

https://www.orlandomedicalnews.com/article/3545/letter-to-the-editor-why-increasing-number-of-cases-of-covid-19-is-not-bad-news

Letter to the Editor: Why Increasing Number of Cases of COVID-19 is NOT Bad News

By JOHN T. LITTELL, MD

Several times a day, on every possible news outlet, we are bombarded with updates as to the new number of “cases” of COVID-19 in the U.S. and elsewhere.  News analysts then use these numbers to justify criticisms of those who dare to reject the CDC’s recommendations with regards to mask wearing and social distancing.   It is imperative that all Americans  – and especially those in the medical profession – understand the actual definition of a “case” of COVID -19 so as to make informed decisions as to how to live our lives.

Older Americans remember all too well the dread they experienced when a family member was diagnosed with a “case” of scarlet fever, diphtheria, whooping cough (pertussis), or polio.  During my career in family medicine, including several years as an Army physician, I have cared for patients with chickenpox, shingles, Lyme disease as well as measles, tuberculosis, malaria, and AIDS.   The “case definition” established for all of these diseases by the CDC requires the presence of signs and symptoms of that disease.  In other words, each case involved a SICK patient.  Laboratory studies may be performed to “confirm” a diagnosis, but are not sufficient in the absence of clinical symptoms.

Having now been privileged to care for sick patients with COVID-19, both in and out of the hospital setting, I am happy to see the number of these sick patients dwindle almost to zero in my community – while the “case numbers” for COVID-19 continue to go up.  Why is that?

In marked contrast to measles, shingles, and other infectious disease, “cases” of COVID-19 do NOT require the presence of ANY symptoms whatsoever.   Health departments are encouraging everyone and anyone to come in for testing, and each positive test is reported as yet another “new” case of COVID-19!

On April 5, 2020, a small number of state epidemiologists (Council of State and Territorial Epidemiologists (CSTE) Technical Supplement: Interim-20-ID-01) came up with a “surveillance” case definition for COVID-19.  At the time, there was uncertainty as to whether or not completely asymptomatic persons could transmit COVID-19 sufficiently enough to infect and cause disease in others. (This notion has never been proven and, in fact,  has recently been discounted – cfr “ A Study on the Infectivity of Asymptomatic SARS-CoV-2 Carriers,  Ming Fao et al, Respir Med, 2020 Aug – available online through PubMed 2020 May 13, as well as recent reports from the WHO itself).   The CSTF thereby justified the unconventional case definition for COVID-19, adding  “CSTE realizes that field investigations will involve evaluations of persons with no symptoms and these individuals will need to be counted as cases.”

Hence, anyone who has a positive PCR test (the nasal swab, PCR test for COVID Antigen or Nucleic Acid) or serological test (blood test for antibodies –IgG and/or IgM) would be classified as a “case” – even in the absence of symptoms.   In our hospitals at this time, there are hundreds of former nursing home residents sitting in “COVID” units who are in their usual state of good health, banned from returning to their former nursing home residences simply because they have TESTED Positive for COVID-19 during mass testing programs in the nursing homes.

The presence of a positive lab test for COVID-19 in a person who has never been sick is actually GOOD news for that person and for the rest of us.  The positive test indicates that this person has likely mounted an adequate immune response to a small dose of COVID-19 to whom he or she was exposed – naturally (hence, no need for a vaccine vs. COVID-19).

It is important as well to understand that the presence of lab testing is not the ONLY criterion that the  the CDC uses to established a diagnosis of COVID-19.  The presence of only 1 or 2 flu-like symptoms (fever,chills, cough, sore throat,  shortness of breath)  – in the absence of another proven cause (e.g., influenza, bacterial pneumonia) is SUFFICIENT to give a diagnosis of COVID-19 – as long as the patient also meets certain “epidemiological linkage” criteria as follows:

“In a person with clinically compatible symptoms,   [a “case” will be reported if that person had] one or more of the following exposures in the 14 days before onset of symptoms: travel to or residence in an area with sustained, ongoing community transmission of SARS-CoV-2; close contact (10 minutes or longer, within a 6 foot distance) with a person diagnosed with COVID-19; or member of a risk cohort as defined by public health authorities during an outbreak.”  Note that the definition of a “risk cohort” includes age > 70 or living in a nursing home or similar facility.

So, in essence, any person with an influenza- like illness (ILI) could be considered a “case” of COVID-19,  even WITHOUT confirmatory lab testing.  The CDC has even advised to consider any deaths from pneumonia or ILI as “Covid-related” deaths – unless the physician or medical examiner establishes another infectious agent as the cause of illness.

Now perhaps you see why the increasing number of cases, and even deaths, due to COVID-19 is fraught with misinterpretation and is NOT in any way a measure of the ACTUAL morbidity and mortality FROM COVID-19.   My patients who insist upon wearing masks, gloves and social distancing are citing these misleading statistics as justification for their decisions (and, of course, that they are following the “CDC guidelines”).  I simply advise them, “COVID-19 is NOT in the atmosphere around us; it resides in the respiratory tracts of infected individuals and can only be transmitted to others by sick, infected persons after prolonged contact with others”.

So you may ask – why are we continuing to report increasing numbers of cases of COVID as though it were BAD news for America? Rather than as GOOD news, i.e, that the thousands of healthy Americans testing positive  (also known as  “asymptomatic”)  are indicative of the presence of herd immunity – protecting themselves and many of us from potential future assaults by variants of COVID?

Why did we as a society stop sending our children to schools and camps and sports activities?  Why did we stop going to work and church and public parks and beaches?  Why did we insist that healthy persons “stay at home” – rather than observing the evidence-based, medically prudent method of identifying those who were sick and isolating them from the rest of the population –   advising the sick to “stay at home” and allowing the rest of society to function normally?  And, while we witnessed the gatherings of protestors in recent days with little concerns for COVID-19 spread among these asymptomatic persons, most certainly many are hoping  that the increasing “case” numbers for COVID-19 will discourage folks from coming to any more rallies for certain candidates for political office.

Fear is a powerful weapon.  FDR famously broadcast to Americans in 1933 that “We have nothing to fear, but fear itself”.  I would argue that we have to fear those who would have us remain fearful and servile and willing to surrender basic freedoms without justification.

John Thomas Littell, MD, is a board-certified family physician. After earning his MD from George Washington University, he served in the US Army, receiving the Meritorious Service Medal for his work in quality improvement, and also served with the National Health Service Corps in Montana. During his eighteen years in Kissimmee, FL, Dr Littell has served on the faculty of the UCF School of Medicine, President of the County Medical Society, and Chief of Staff at the Florida Hospital. He currently resides with his wife, Kathleen, and family in Ocala, Florida, where he remains very active as a family physician with practices both in Kissimmee and Ocala. To learn more, visit johnlittellmd.com

Learn to live with virus: NY Times

Around the world, governments that had appeared to tame the coronavirus are adjusting to the reality that the disease is here to stay. But in a shift away from damaging nationwide lockdowns, they are looking for targeted ways to find and stop outbreaks before they become third or fourth waves.

https://www.nytimes.com/2020/06/24/world/europe/countries-reopening-coronavirus.html

Covid-19 elimination impossible, so time for New Zealand to change direction

By Ananish Chaudhuri, Simon Thornley, Michael Jackson.

20/6/2020

877 words

The recent fiasco that allowed people to leave quarantine without testing, risking spread of Covid-19, highlights how nebulous the government’s claim of total elimination always was. The government, in projecting thousands of deaths that never eventuated, has continued with a story that the virus can be eliminated if we all play our part. The façade of a watertight border has been shattered, and the government broke its own quarantine rules. We urgently need to reconsider whether an ‘elimination at all costs’ strategy makes sense, as many other countries are moving on and opening up their borders.

Like other coronaviruses, Covid-19 is here to stay and a vaccine will be a long time coming. Studies show that respiratory viruses are ubiquitous. Over two years, in a cohort of 214 people who were sampled every week in New York, 70% had at least one positive test for a respiratory virus, with the vast majority having few symptoms of infection.

And even if we do get a vaccine, its efficacy is far from guaranteed. Vaccines against seasonal flu are often ineffective since we are often vaccinating against last year’s strain while the virus has already mutated.

Vaccines need to be thoroughly tested before they are offered to the populace. The usual process is to go through three phases of clinical trials. At present, only one vaccine is in phase 2, where safety and dose information is tested in a large group. The critical phase of testing efficacy (phase 3) is the most time-consuming step and often takes years. With the virus now waning in many countries, demonstrating the effectiveness of the vaccine will be difficult, since exposure to the virus will be rare. The sooner we face up to this fact, the better off we will all be. Sooner or later, we will have more cases; at least ripples, if not a wave. We will need to learn to tolerate further cases.

However, based on what we know about the virus at this point, there is no reason to panic. First, contrary to what was claimed earlier, the infection fatality rate of Covid-19 is around 0.25 percent. Many people who contract the virus show few symptoms and the age distribution of fatality with the virus is similar to day-to-day life. Serological tests are telling us that a much larger proportion of the population has immunity against the virus. Even in those who test negative, a high proportion are showing other signs of immunity, through a separate cell-mediated pathway. With more of us already protected, it is harder for the virus to spread.

Second, the most at risk are the elderly, especially those who are frail with other illnesses. This does not mean that we should be willing to sacrifice our parents and grandparents. It simply means that we need to exercise greater caution around the elderly, particularly those in care homes and in hospitals. The majority of deaths with Covid-19 have been in rest homes. Conversely, this also means that we don’t need to worry too much about the young and the healthy. Children especially seem virtually immune to the disease.

Third, countries all around the world have started opening up. Slovenia has opened its border with Italy, the hardest hit country. The government of Slovenia has declared the epidemic over and is now rather prioritising economic recovery. Across Europe countries are moving to open up their borders, as their governments reassess the risk posed by the virus.

Given this, it seems bizarre that our border is still tightly closed, even with our Pacific neighbours including Cook Islands, a state that is associated with New Zealand. The Cook Islands earns 80% of its revenue from tourism mostly from New Zealanders who holiday there.

Lockdowns are not and never were a panacea. There is very little evidence that lockdowns mitigate the spread. The theory indicates that they slow cases down, rather than reduce overall numbers. Our firm lockdown will cause a significant economic misery with public debt climbing to more than 50% of our GDP in about 2 years’ time. Unemployment will increase sharply and it is well documented that higher unemployment lowers life expectancy, not to mention potential self-harm.

Current predictions are for a 15.8% drop in GDP in the second quarter of the year, suggesting that the Finance Minister’s suggestion of a 4.8% drop during the budget presentation was underestimated.

Behind the scenes, lockdowns, here and elsewhere, are causing havoc. The evidence is emerging gradually. Required tests and surgeries have been postponed and vaccinations have been delayed. Both lives and livelihoods have taken a hit. Around the world, about 80 million children have not been vaccinated leading to a sharp increase in measles, diphtheria and cholera.

It is now time to take stock. The government has broken its own rules to eliminate the virus. Simultaneously, Covid-19 is not as dangerous as it was first thought to be. Serology tests overseas clearly show that the virus has got to many more people than appreciated. We urgently need to assess our own population’s susceptibility to the virus, as we reconsider the border question. It is time for recalibration of the threat, and to prioritise flattening the economic recession curve, rather than doubling down on a fragile and myopic vision of elimination.

Stanford study reveals why COVID19 forecasts failed

…models failed when they used more speculation and theoretical assumptions and tried to predict long-term outcomes, e.g. using early SIR-based models to predict what would happen in the entire season. However, even forecasting built directly on data alone fared badly. E.g., the IHME failed to yield accurate predictions or accurate estimates of uncertainty. Even for short-term forecasting when the epidemic wave has waned, models presented confusingly diverse predictions with huge uncertainty.

 

…epidemic forecasting continued to thrive, perhaps because vastly erroneous predictions typically lacked serious consequences. Actually, erroneous predictions may have been even useful. A wrong, doomsday prediction may incentivize people towards better personal hygiene. Problems starts when public leaders take (wrong) predictions too seriously, considering them crystal balls without understanding their uncertainty and the assumptions made.

https://forecasters.org/blog/2020/06/14/forecasting-for-covid-19-has-failed/

 

Millions of accumulated years of life will be lost to Covid-19 response

[Lockdown] policies have created the greatest global economic disruption in history, with trillions of dollars of lost economic output. These financial losses have been falsely portrayed as purely economic. To the contrary, using numerous National Institutes of Health Public Access publications, Centers for Disease Control and Prevention (CDC) and Bureau of Labor Statistics data, and various actuarial tables, we calculate that these policies will cause devastating non-economic consequences that will total millions of accumulated years of life lost in the United States, far beyond what the virus itself has caused.

https://thehill.com/opinion/healthcare/499394-the-covid-19-shutdown-will-cost-americans-millions-of-years-of-life

A request for balanced analysis and reporting

Drs Michael Jackson and Simon Thornley

A recent article in a New Zealand newspaper claims that Sweden’s approach to managing the Covid pandemic means that “56,000 more people may yet die”. We believe the article is misleading because:

  1. The author assumes an ‘infection fatality proportion’ (IFP) of 1% and states it’s the “current best estimate”. This estimate is derived from seroprevalence studies from just two countries (France and Spain – both with high per capita death rates). But, the Centre for Disease Control’s (CDC) recent best estimate is 0.26% (four times lower). A summary of studies (19 May) by Professor John Ioannidis that included studies from Asia, Europe, and North and South America derived an estimate of between 0.02% to 0.40%. This mirrors the IFR provided by the Centre for Evidence-Based Medicine at Oxford University. We believe the use of a high IFP is misleading as it produces an estimate that wasn’t based on current best estimates.
  2. The author does not include any commentary about the recent identification of cross-reactive T-cells. The paper’s findings (published May 14 and before the author’s article was published) indicate between 40-60% of a population may not even be susceptible to Covid-19 due to prior exposure to other coronaviruses that cause the common cold. This has important implications, as it lowers the number of people susceptible to infection. More recently (we acknowledge after the article was published), one of the world’s most influential neuroscientists and statisticians, Professor Karl Friston (University College London) said the figure could be as high as 80%. The inclusion of this information would have allowed for the re-calculation of an estimated fatality rate and provided the reader with further information about the uncertainty of the author’s predictions.
  3. The author assumes that 60% of a population needs to be have been infected or vaccinated to achieve herd immunity. But some are calculating it at 40% based on Sweden-specific data, not generic inputs. Also, the 60% figure is based on modelling, rather than measured seroprevalence. Given the previous data about T cell immunity and cross-reactivity of other antibodies, the true population immunity is likely to be much higher than seroprevalence surveys indicate. Again, this paints a more negative picture and doesn’t present the reader with a balanced view.
  4. The author states “After completing this article, a new study has reported that the proportion of people in Stockholm with antibodies to Covid-19 is only 7.3 per 100 people”. But an internet search will tell that the 7.3% figure “reflects the state of the epidemic earlier in April”. That’s a whole month before the article was written and when the total number of deaths in Sweden was around 1000. Sweden’s Public Health Agency estimates the figure would now be about 20% but this isn’t mentioned by the author.
  5. The author does not attempt to consider how his prediction of 56,000 extra deaths matches actual recorded data and trends for Covid-19 in Sweden (figure). With 4,874 deaths currently, and a clear downward trend (also evident when the author published his article), the author’s prediction is unrealistic.

Figure. Covid-19 daily mortality in Sweden (16/6/2020). Line indicates trend.

  1. The author claims that Sweden’s economy hasn’t fared any better than its neighbours, despite its more relaxed approach. Again, this is misleading. While this may be true for Denmark and Norway (note Norway now say they could have achieved the same results without a lockdown), Sweden’s projected downturn (1% GDP) is less than Germany (6.5%), the Netherlands (6.8%), the EU as a whole (7.4%), Belgium (8%), France (8.2%), Croatia, (9.1%), Spain (9.4%), Italy (9.5%), Greece (9.7%) and the UK (up to 14%). For comparison, the New Zealand government is predicting a downturn of around 10%. You may also be surprised to hear Sweden’s economy actually grew in the first quarter of 2020 compared to declines across Europe. The UK’s economy, for example, contracted by 2% over the same period.

We are not, here, looking to justify of Sweden’s approach. Only time will tell if Sweden took the right one. We are simply asking that commentators present their work in a balanced, evidence-based way – one that draws the reader’s attention to the complexity and uncertainty in their projections. Figures like “60,000 deaths” are headline-grabbing but are based on incomplete and overly simplistic modelling. They are not ‘reasonable best estimates” based and clearly contradict observed trends.

Learning from new Covid-19 data

Simon Thornley

15/6/2020

Words: 670

In the response to Covid-19, it is easy to forget that our knowledge of the virus is provisional and still evolving. We have seen, for example, that the infection fatality rate, initially given as 3.4%, now with serology data has been dialled back considerably to between 0.02 to 0.40% which is in the range of severe influenza. This updated information brings an inevitable conflict with political decision making, in which actions are often justified at all costs.

We have now seen evidence of this, with the Medical Director of the Royal New Zealand College of General Practitioners, Dr Bryan Betty, stating that New Zealand was staring down the barrel of a “potential health system meltdown.” He continued: “We were literally one week away from that or we were going down a track of lockdown, which actually halted the spread of the coronavirus in New Zealand. You’ve got to remember that at that time we had exponential growth going on… [Our case numbers] were doubling every day.”

On the face of it, this sounds reasonable. We were looking down the barrel… Let’s pull out all the stops.

Several of Betty’s statements deserve scrutiny. The first is that numbers were doubling every day. They weren’t. In the days immediately before lockdown, numbers increased by 4 from 36 to 40 on the 24th of March, an 11% increase, the next day to 50 (25% increase), then level 4 was instituted. Only for one day did numbers at least double (23rd of March).

The statement that we were staring at a health system meltdown is exaggerated. During the so called “crisis”, hospitals had spare capacity. Hospitals were quiet, so quiet in fact, that specialists expressed concern about it. Intensive care units likewise. In fact, we now have the opposite problem with some primary care practitioners going broke owing to lack of demand and the costs of adapting to new service models. Patients with other conditions were clearly foregoing usual care.

The dire modelling, predicted, even with strong mitigation measures, never eventuated. If there is one thing this teaches us, it is that our understanding of the virus needs updating. The 80,000 predicted deaths are an overestimate of the observed mortality number by 3,400 times. In deciding policy responses, we desperately need to take account of the evolving nature of both the science and the available information rather than rely on outdated models.

A scientific approach involves learning from mistakes. The Norwegian Prime Minister, Erna Solberg admitted that she panicked into a decision to close schools and early childhood centres. Similarly, the Director General of Health in the Scandinavian country, Camilla Stoltenberg, stated that they could have achieved the same result by ‘not locking down’.

Here, we see both politicians and health officials learning from mistakes. Rather than being an admission of failure, it is a logical and healthy response to new information. This response contrasts strongly with some of New Zealand’s leaders.

We are rapidly learning that the threat posed by the virus is not as serious as we have been led to believe. New research shows that immunity is likely to be more widespread than we have previously appreciated. Immunity to this virus is also likely since other scientists have found cross-reactivity to other coronaviruses that cause the common cold. Many more of us are likely to have seen the virus than our case numbers indicate.

This new knowledge must lead to an update of policies for the country. We should continue to question whether it still makes sense for us to keep our borders firmly closed in the light of this new information. Serosurveys of New Zealanders would help us judge more accurately the degree of spread of the virus. If the virus has circulated to many more people than we think, and many more are protected than we previously believed, then we can have confidence to open our borders. Slovenia and Italy have already done this for several weeks and thus far they have not had second waves (figure).

Figure. Daily counts of Covid-19 cases for Slovenia and Italy, two European countries with open borders to European Union citizens.