Tuesday, 10th March: Tomas Pueyo, an engineer from Stanford who leads a billion-dollar business, publishes Coronavirus: Why You Must Act Now. Shows dangerous exponential growth occuring in most countries. Since translated into 30 languages.
Monday, 16th March: NM writes one-page document to send to WA upper house politican and Federal MP. De-identified version of this document posted on FaceBook is shared over 300 times.
Tuesday, 17th March: One-page document is forwarded to a Federal Senator. Later that day, a more lengthy two-page document is prepared by NM, AC and MP and send to the same Senator. Posted on FaceBook with full author attribution.
Wednesday, 18th March: Third document prepared by NM showing that NSW and VIC around one-week away from point at which the Wuhan lockdown triggered. Document sent to Federal MP and same information published on FaceBook.
Friday, 20th March: Tomas Pueyo publishes The Hammer and the Dance, comparing various options available to government to control the pandemic. His preferred option is very similar to that proposed by NM on 16th March.
Saturday, 21st March: NM sends Dispersal Approach concept to Federal MP. Dispersal cannot presently be used since asymptomatic carriers would trigger mini-epidemics far from hospitals. Would have been viable in late February when numbers were low. A future option also.
Sunday, 22nd March: Unhelpful opinion piece published in The Conversation. Majority of article discusses options where cases double every 4 days. Australia in far more dangerous situation (WA doubles every 2.8 days, VIC and QLD double every 3.0 days) hence lockdown is imminent.
Monday, 23rd March: Brilliant cartoon published by First Dog on the Moon. Explains why we need to go home and stay home. Should be letter-dropped to every household.
Wednesday, 25th March: Excellent article reporting modelling from University of Sydney. If 80% of population voluntarily stays at home, the virus gradually dies out. At 70% it continues to grow, while at 90% the decline is much faster, at around 100 days.
Thursday, 26th March: Outstanding piece of journalism from the ABC explaining why exponential growth matters. Compares the differing responses of the ASEAN nations to the rest of the world. A must-read article.
Saturday, 28th March: NM prepares mathematical analysis suggesting that growth of new cases appears to be trending sub-exponentially in most Australian jurisdictions. This is consistent with control measures producing a constant infection rate.
Sunday, 29th March: NM prepares new mathematical analysis demonstrating that national statistics for Australia transformed abruptly from exponential to linear growth on March 22nd. Consistent with Australia pursuing a herd immunity strategy.
Monday, 30th March: NM prepares financial analogy to explain the difference between linear growth and exponential growth and why it matters that growth in Australia is no longer exponential.
Thursday, 2nd April: WA Premier Mark McGowan announces Island WA policy implementing hard border with enforced 14-day quarantine for all in-bound travel.
Sunday 12th April: The number of new daily cases in Australia is presently trending towards zero in most jurisdictions. The exception is NSW where a cohort of community transmission is generating around 40 new cases each day. Full details and graphical analysis at the Curtin git-hub repository.
Sunday 12th April: Some countries which experienced a catastrophic outbreak (e.g. Italy and Spain) have passed peak new daily cases and are now tapering downwards. France approaching peak. Stringent control measures will still be required in these countries for a number of weeks. UK tracking along a similar path to Italy and can be placed to the "Catastrophic Outbreak" category. Netherlands and Sweden appear to be following mitigation strategy (AKA herd-immunity). Greece acted early and has many fewer deaths than its European neighbours. NZ has almost no deaths. Despite a large number of absolute cases and deaths, on a per-capita basis the USA is better than a number of countries.
Data presently available for 15 countries (AU, CA, CH, DE, DK, ES, FR, GR, IT, NL, NZ, PT, SE, UK, US). Graphical analysis at the Curtin git-hub repository.
Plotting the number of new cases per day divided by the number of ICU beds provides a simple means to compare how various countries are tracking. The time axis for each country is shifted so that zero corresponds to the date when growth changed from exponential to linear. This enables a equivalent comparison of the time-evolution of the epidemic between countries. Australia, Canada and the USA are looking very much better than Italy, while other countries are significantly worse.
For each confirmed case, around 1 in every 20 will need high-level care in hospital. On the optimistic assumption that each ICU bed is occupied for 10 days, this means a best case scenario of 2 new cases per day per ICU bed (since 0.1x20=2) . Beyond this threshold patients arrive faster at the hospital than they leave, and sick people pile up in the hallways. In reality, hospitals are already busy places and most of the ICU beds are in use for other patients. For example, if only 10% of the ICU beds are available for COVID patients, then the threshold for collapse is 0.1x2=0.2 new cases per day per ICU bed. In Italy this figure is the number of new daily cases/bed is around 0.77 which is why so many people have died. In Spain this figure is even higher at around 1.7; this is placing overwhelming pressure on the health system and Spanish society in general.
Information on ICU beds in various countries obtained from Wikipedia plus here, here and here.
This web-site is prepared by Nigel Marks. He has a PhD in Physics, with an emphasis on computer simulation of atoms. He has substantial experience with nuclear technologies, where the underlying mathematics of the chain reaction is identical to that of an epidemic.
The documents and analysis above have been prepared in collaboration with Andrew Currie and Matthew Payne. Andrew has a PhD in Immunology, with an emphasis on infection and immunity. He has experience in measuring human immunity and responses to pathogens and vaccines. Matthew has a PhD in Microbiology with specialist skills in molecular diagnosis of infection and pathogenesis and has developed novel diagnostic tests for other infectious diseases.
The documents have been posted on NM's FaceBook page and discussed on threads within. The purpose of this page is to collate these interactions in a coherent manner.