Sprinting Ahead of a Catastrophe – Epidemiological Math and Social Isolation

Fire and EMS agencies are examples of the Catastrophic Theory of Reform. Many were created in the aftermath of a tragedy. Unfortunately, reform comes with detailed after-the-incident analysis, allowing us to understand the elements that combined to make the catastrophe. With COVID-19 we are running in front of a mounting wave of calamity as we try to reduce the impact based on incomplete information buried in an ocean of panic and nonsense.

Epidemiological Math

Seven weeks ago there were media reports of flu-like illness in China. The exponential growth of the disease is independent of international borders, socio-economic background or political affiliation. The catastrophic aspect is not the total number of those infected, but the number of infected that will require hospital-based intensive care.

Yascha Mounk, reporting for The Atlantic, provides the detail from Lombardy, a well-resourced community in northern Italy known for world-class health care:

Two weeks ago, Italy had 322 confirmed cases of the coronavirus. At that point, doctors in the country’s hospitals could lavish significant attention on each stricken patient.

One week ago, Italy had 2,502 cases of the virus, which causes the disease known as COVID-19. At that point, doctors in the country’s hospitals could still perform the most lifesaving functions by artificially ventilating patients who experienced acute breathing difficulties.

Today, Italy has 10,149 cases of the coronavirus. There are now simply too many patients for each one of them to receive adequate care. Doctors and nurses are unable to tend to everybody. They lack machines to ventilate all those gasping for air.

(2020 March 11) The Extraordinary Decisions Facing Italian Doctors. The Atlantic

Italy reports a one-day death tool of 368 on Sunday, March 15, raising its total number of deaths to 1,809. It has 24,747 people infected with the virus.

This March 12th chart from The Economist shows that the United States is on the way to match Italy in patients with coronavirus.

days since 100th case

Old-School Social Distancing to Flatten the Curve

We need to lower the rate of new sick patients needing definitive care. Overloading the hospitals with critically sick patients will increase the death rate.

We have an example from the 1918 War Bond parades in Philadelphia and Saint Louis. Philadelphia decided to have the parade, Saint Louis canceled theirs. Within three days of the parade, every bed in Philadelphia’s 31 hospitals were full of influenza patients.

1918 isolation Postponing sporting events, the Fire Department Instructor’s Conference and closing schools are designed to reduce the rate of infection of the coronavirus. We will probably see more isolation zones like the one in New Rochelle, Westchester County, New York.

Times Square_Earl Douglas

Times Square early Saturday morning – Earl Douglas

I anticipate extended venue closures, more calls to self-isolate, additional isolation zones and restricted travel over the next couple of months. We may see temporary hospitals established in high cluster areas.

The Centre for the Mathematical Modelling of Infectious Diseases COVID-19 Working Group shared this research in February:

In most scenarios, highly effective contact tracing and case isolation is enough to control a new outbreak of COVID-19 within 3 months. The probability of control decreases with long delays from symptom onset to isolation, fewer cases ascertained by contact tracing, and increasing transmission before symptoms.

This model can be modified to reflect updated transmission characteristics and more specific definitions of outbreak control to assess the potential success of local response efforts.

Hopefully, our efforts to isolate humans will slow down the virus rate of growth to give us a fighting chance to take care of our critically sick and reduce this threat.

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Committee on Guidance for Establishing Crisis Standards for Care for Use In Disaster Situations (2012 March 21) Crisis Standards of Care: A Systems Framework for Catastrophic Disaster Response. Washington DC: Institute of Medicine, The National Academies.  Accessed 3/15/2020 https://www.ncbi.nlm.nih.gov/books/NBK201074/

Mounk, Yascha (2020 March 11) The Extraordinary Decisions Facing Italian Doctors: There are now simply too many patients for each one of them to receive adequate care. The Atlantic. Accessed March 15, 2020:   https://www.theatlantic.com/ideas/archive/2020/03/who-gets-hospital-bed/607807/ 

staff (2020 March 13) Politics and Pandemics. The Economist. Accessed March 15, 2020: https://www.economist.com/graphic-detail/2020/03/13/politics-and-pandemics

Flynn, Megan (2020 March 12) What happens if parades are not canceled during pandemics? Philadelphia found out in 1918, with disastrous results. The Washington Post. Accessed March 15, 2020: https://www.washingtonpost.com/nation/2020/03/12/pandemic-parade-flu-coronavirus/

Barry, John M. (2005) The Great Influenza: The Story of the Deadliest Pandemic in History. New York: Penguin Books.

Hellewell, J., Abbott, S. Gimma, A., et al (2020 February 28) Feasibility of controlling COVID-19 outbreaks by isolation of cases and contacts. The Lancet. Accessed 3/15/20: https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(20)30074-7/fulltext

Sheehan, Kevin and Feis, Aaron (2020 March 12) National Guard enforces New Rochelle coronavirus ‘containment area’ New York Post  https://nypost.com/2020/03/12/national-guard-enforces-new-rochelle-coronavirus-containment-area/

Featured image from Prince George’s County Professional Fire Fighters & Paramedics Association.