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Covid-19: how doctors and healthcare systems are tackling coronavirus worldwide

BMJ 2020; 368 doi: (Published 18 March 2020) Cite this as: BMJ 2020;368:m1090

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COVID-19: chaos, complexity and complex systems to help doctors and healthcare systems tackle coronavirus worldwide

Dear Editor

Chaos, complexity and complex systems science should be able to help doctors and healthcare systems tackle the challenges of coronavirus worldwide described by Hopkins et al (1). The worldwide differences described emerged from their unique past, and will change, reflecting many influences, including how they respond to these complex challenges.

Complex systems reflect the science of chaos and complexity, with complex dynamic interactions of many interconnected and interdependent parts with feedback, adaptation and change, leading to sudden transitions, unpredictability, uncertainty, apparent randomness and novel outcomes with new features (2,3).

Viruses are complex adaptive systems (4), producing predictable and unpredictable effects from interaction and adaptation to different environments, creating a variety of challenges and outcomes as seen in this pandemic, requiring different responses at different phases (5).

We can learn from this worldwide experience, using chaos, complexity and complex systems thinking, with complexity considered the science for the 21st century by Stephen Hawking, and the science for a complex world by the Santa Fe Institute, and increasingly used to help manage the chaos caused by this virus.

These systems and challenges worldwide reflect complex dynamic political, policy, social, cultural, biological and other nonlinear interactions producing a variety of predictable and unpredictable outcomes, as in the differences described. They manifest at the bedside with rapidly changing novel situations, like unusual respiratory infections, highly unusual multi-organ thrombosis, novel ECG abnormalities, etc, as well as system challenges of bed, ventilator and PPE shortages, which all change outcomes, as well reported.

Complex systems call for different leadership, management and decision approaches at different stages, illustrated in a Cynefin model (5), with simple or obvious - straightforward responses, complicated – need technical expertise, complex – sense, try, feedback adaptation and change, and chaos - immediate decisive action plus feedback adapt and change to move from chaos to complex, used singly or in combination.

In the early phase of this pandemic, many countries in the East responded with definitive early and sustained preventive and other actions considered successful, many in the West with a mismatch - delay and unpreparedness, leading to costly failures. Continuing to track differences as reported, and learning from them are valuable.

A chaos, complexity and complex systems approach may help us to better understand and envisage worldwide differences, and help to tackle the ensuing multitude of challenges at the different stages of this pandemic, with a 21st century science based approach, likely producing better outcomes and saving lives.  

1 Hopkins J, Hayasaki E, Zastrow M, et al. Covid-19: how doctors and healthcare systems are tackling coronavirus worldwide.
BMJ 2020; 368 doi: (Published 18 March 2020) accessed April 20, 2020.

2 VS, Rambihar SP, Rambihar VS Jr. Tsunami Chaos and Global Heart: using complexity science to rethink and make a better world. 2005. Vashna Publications. Toronto, Canada. (accessed April 20, 2020).

3 Rambihar VS. Chaos, complexity and systems thinking to contain and manage COVID-19. CMAJ 6 April 2020. Available at (Accessed April 20, 2020).
4 Solé R, Elena SF. Viruses as Complex Adaptive Systems. 2019. Princeton University Press, Princeton, USA.
5 Snowden D, Boone M. A Leader’s Framework for Decision Making. Harvard Business Review Nov 2007. Accessed April 20, 2020.

Competing interests: No competing interests

27 April 2020
Vivian Rambihar
Courtesy Staff - Sunnybrook Health Sciences Centre and The Scarborough Network, Toronto Canada. Adjunct Assistant Professor of Medicine, University of Toronto.
Toronto Canada