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SARS-CoV-2 genome: A=Purple T=Orange C=Yellow G=Red[1]

The physician and health researcher Hans Rosling regarded the greatest risks to human civilisation as global pandemic, financial collapse, world war, climate change, and extreme poverty.[2] Could the coronavirus disease (COVID-19)[3] which emerged in Wuhan, China, in late 2019, and in early 2020 reached pandemic status, be the pandemic Rosling feared?

The 1918 Spanish Flu killed up to 100 million people in a year, and in the 14th century the Black Death killed between a quarter and a half of the populations it affected,[4] but neither destroyed civilisation (although the plague resulted in widespread social changes in its aftermath).[5]

Modelling work by researchers at Imperial College[6] suggest that, with no action by governments, the Coronavirus would kill around 2 million people in the US and half a million in the UK. With drastic measures to suppress spread of the virus the death toll could have been kept to below 20,000 in Britain (the researchers didn't publish figures for the USA).

What makes the big difference in numbers?

The flat red line is the capacity of the health system to cope with critical care patients

The Imperial College researchers modelled various scenarios for mitigating the spread of the disease, aiming to find a strategy which kept the numbers of people so badly affected that they need hospital treatment within the resources of the health system to treat them. Put bluntly, without hospital treatment, and especially without the availability of ventilators to assist breathing, most people who need treatment will die. With treatment about half will survive.

The model showed that none of the mitigation strategies which were less disruptive to society than a full lockdown worked.

However even the severe lockdown strategy does not halt the spread of the virus; it just reduces it to a low level, which will spring back again when and if restrictions are lifted.

Without mitigation the epidemic might lead to enough survivors having acquired immunity to the disease[7] to protect those who have not yet had it via herd immunity, and this does seem to have been the UK government's strategy before the Imperial study was published,[8][9] despite the larger, avoidable, toll of death, injury[10] and suffering it would entail.

Without the possibility of herd immunity we need a vaccine to end the infection, just as the advent of vaccines ended outbreaks of smallpox, diptheria, polio etc (and might have eradicated measles had non-medical factors not intervened). However it is estimated that it will take 12 to 18 months for a safe and effective vaccine to be available and widely deployed, so in the meantime how do we cope?

Adaptive triggering of restrictions depending on number of ICU cases

The Imperial team found that cases could be kept below a level which overwhelms health facilities if restrictions of social distancing etc are relaxed only when the number of cases in Intensive Care Units fall below a certain threshold (e.g. 50 cases per week), and are re-imposed when ICU cases rise above another, higher, threshold number (such as 100 cases/week).

How does C19 compare with Spanish and ordinary flu?

COVID-19 compared to Spanish and seasonal flu[11]

The best-case figure for UK COVID-19 deaths with vigorous mitigation measures is 20,000 people.[6] The population of the UK is about 66 million, so that is 0.03% of the population, or about one person in three thousand.

The figure of 510,000 in the UK without mitigation is 0.77%, or about one in every 130.[6]

For comparison the death rate from Spanish flu has been estimated at somewhere between 0.8% (one in 125) and 5.5% (one in 18).[12]

Ordinary seasonal flu claims about 0.05% (about one in twenty thousand).[12]

Thus the worst case for an unmitigated Coronavirus epidemic is similar to the lowest estimate of the death rate of the 1918 Spanish Flu.

However the Spanish flu pandemic was over a century ago, at a time when one in ten babies died before reaching their first year and life expectancy was far lower, even in the UK, which was then the most prosperous country in the world.[13] Public health, and health expectations amongst the public, have changed radically in the intervening years, and the grim death toll of the earlier pandemic would today be regarded as horrific – and no doubt politically unacceptable, if it were known that an alternative were possible.

How does C19 compare with other causes of death?

COVID-19 compared to other causes of death[11]

Deaths from air pollution in the UK are 0.1% (about one in every thousand) per year.[14]

The UK has an average of 32,000 excess deaths each winter (0.05%, or one in two thousand) of which 9,700 (0.015%, one in seven thousand) were due to cold homes.[15] In the winter of 2017-2018 the number dying due to cold homes peaked at 17,000 (0.026%, one in four thousand).[16]

World-wide about 1.5 million people – mostly young children – still die of vaccine-preventable diseases. That's 0.02%, or one in five thousand.[17]

In the UK about 2000 people are killed on the roads each year: 0.003% (about one in forty thousand).[18]

An unmitigated COVID-19 epidemic would be a public health (and possibly political) disaster, but with mitigation the health effects might be brought down to levels comparable with other public health issues, some of which claim even more lives.

Suppressing the Coronavirus

Outcomes with the lowest death tolls depend on drastic measures to suppress spread of the virus:

  • social distancing of the entire population,
  • isolation of all cases,
  • quarantine of entire households where anyone is sick, and
  • closure of all schools and universities,

and for these measures to be maintained, on and off, for 12 to 18 months, until a vaccine is available.[19] These measures will be hugely disruptive on many levels: physical, economic, social, and possibly political.

Social distancing

Compared to attempting to quarantine affected populations (or doing nothing) social distancing, where people reduce their contact with others, works best for slowing the spread of the virus. This article shows graphically how effective these approaches are.[20]

Such extreme and rigorous distancing requires that most of the population, except workers in health and other essential services, stay at home for the duration of virus-suppression periods of several months at a time. Obviously this requires that those staying at home have means to live on: food, fuel, electricity, internet and health care. And that those without homes have them. Otherwise the effort to suppress the virus will take longer, or fail altogether, as those in hardship because of isolation are liable to go out to try to find work or the resources to support themselves. This poses challenges in societies run along neo-liberal lines where the practical necessity of supporting all sections of the population clashes with the ideology of requiring everyone to pay for most of their needs. In the UK the government has broken with prevailing financial policies to support those employees unable to work, but little has been done for the significant portion of the population who are self-employed. This threatens all parts of society: even royalty is not immune to the problem.

What happens after COVID-19?

The "19" in the name refers to the year in which this particular Coronavirus was identified. There are others, and C19 itself will mutate sooner or later. If we are not to spend much of future years and decades in and out of states of lockdown we need to change aspects of human civilisation to reduce our risks and increase our preparedness to tackle such challenges.[21]

One way in which we make ourselves vulnerable is through our relationships with animals. The C19 virus is thought to have crossed from bats to humans in a "wet market", where live wild animals are traded, in Wuhan in China. There are many such markets and other situations in which humans can be exposed to the pathogens of wild animals around the world. There are also hazards from our interactions with, and exploitation of, domesticated animals. The practice of feeding the dried and ground-up remains of dead animals to live cattle resulted in "Mad Cow Disease", and its transmission to humans as variant Creutzfeldt–Jakob disease. The widespread prophylactic use of antibiotics in animal farming risks contributing to antibiotic resistance which poses a huge threat to human welfare.[22] In the context of global heating, the land required for animal – especially cattle – farming, and the land required to grow food for animals, is increasingly obtained by deforestation, which releases CO
and interferes with the ability of large forests such as the Amazon to create their own rain-producing climate. Even where virgin forest is not cleared, the land used for animal farming represents and opportunity cost; without its use for raising animals the same land would be available for other uses such as rewilding/reforestation, solar farms etc.

Footnotes and references

  1. The SARS-CoV-2 genome comprises 8 kilobytes of data, 29,903 base pairs of RNA. When this little string-shaped molecule gets inside a human cell, in its little delivery package, it codes for its own reproduction plus packaging for the new strings, and that is enough to bring the world to its knees. Graphic by /u/dx8xb. Data from Pubmed, GenBank MN908947.3 (From Facebook post by Zi Teng Wang)
  2. "Factfulness: Ten Reasons We're Wrong About the World – and Why Things Are Better Than You Think" by Hans Rosling, Ola Rosling, and Anna Rosling Rönnlund
  3. The virus which causes the COVID-19 disease is called severe acute respiratory syndrome coronavirus 2 (abbreviated as SARS-CoV-2)
  4. "In the Battle Against Coronavirus, Humanity Lacks Leadership" by Yuval Noah Harari in Time on 15 March 2020
  5. "Social and Economic Effects of the Black Death" by Bright Hub Education, observes that

    Before the plague, peasant serfs were confined to their lord’s estate and received little or no payment for their work . Overpopulation and shortage of resources led to malnutrition and extreme poverty for many peasants. After so many people died, serfs were free to move to other estates that provided better conditions and receive top pay for their work. Landowners, desperate for their labor, often provided free tools, housing, seed and farmland . The worker farmed all he could and paid only the rent.

    Serfs improved their standard of living too. Modern day archaeologists have found evidence that prior to the Black Death, most of the peasants relied on clay pots to cook their meals but in years following the plague pandemic, households used more expensive metal cookware.

  6. 6.0 6.1 6.2 "Impact of non-pharmaceutical interventions (NPIs) to reduce COVID19 mortality and healthcare demand" by Neil M Ferguson and others on behalf of the Imperial College COVID-19 Response Team; 16 March 2020
  7. This assumes that survivors do develop immunity to the virus; this is expected from experience with other, similar, viruses, but is not certain, and it is known how long such immunity might last.
  8. The UK's coronavirus policy may sound scientific. It isn't by Nassim Nicholas Taleb and Yaneer Bar-Yam in The Guardian on 25 March 2020
  9. See video in Tweet by @Haggis_UK

    piersmorgan & Matt Hancock go head to head over Dominic Cummings very controversial remarks.. as reported in the Sunday Times. 1/2

    Cummings - "Protect the economy & if that means some pensioners die, too bad"

  10. It is thought that some of those who recover from the disease may suffer long term lung damage.
  11. 11.0 11.1 spreadsheet
  12. 12.0 12.1 "The Spanish flu (1918-20): The global impact of the largest influenza pandemic in history" by Max Roser in Our World In Data on 4 March 2020
  13. "The impact of the Great War on Infant Mortality in London" by Jay Winter, Jon Lawrence, and Jackie Ariouat in Annales de Démographie Historique Année, 1993
  14. "Cardiovascular disease burden from ambient air pollution in Europe reassessed using novel hazard ratio functions" by Jos Lelieveld, Klaus Klingmüller, Andrea Pozzer, Ulrich Pöschl, Mohammed Fnais, Andreas Daiber, and Thomas Münzel in European Heart Journal on 21 May 2019
    See also "Air pollution responsible for more deaths than smoking, study says" by Alex Matthews-King in The Independent on 12 Mar 2019
  15. "UK has sixth-highest rate of excess winter deaths in Europe" by E3G on 23 Feb 2018
  16. "17,000 people in the UK died last winter due to cold housing" by E3G on 15 Feb 2018
  17. "Global decline in vaccine-preventable diseases" by by Samantha Vanderslott, Bernadeta Dadonaite and Max Roser in Our World In Data on July 2015 (revised Dec 2019)
  18. "Reported road casualties in Great Britain: quarterly provisional estimates year ending June 2018" by Department of Transport on 8 Nov 2018
  19. "A chilling scientific paper helped upend U.S. and U.K. coronavirus strategies" by William Booth in The Washington Post (via on 19th March 2020.
  20. "Why outbreaks like coronavirus spread exponentially and how to "flatten the curve"" by Harry Stevens in The Washington Post on 14 March 2020
  21. "We’re not going back to normal" by Gideon Lichfield in MIT Technology Review on 17 Mar 2020

    Social distancing is here to stay for much more than a few weeks. It will upend our way of life, in some ways forever.

  22. A Review of Antibiotic Use in Food Animals: Perspective, Policy, and Potential by Timothy F. Landers, Bevin Cohen, Thomas E. Wittum, and Elaine L. Larson in Public Health Reports, Jan-Feb 2012