The novel coronavirus should prompt a deep re-examination of how densely populated and highly connected cities, especially megacities, can be re-engineered and made safer in the medium and long-term.
Epidemiologists have warned about the increasingly frequent emergence of new diseases since World War Two, most of them of animal origin.
Researchers identified 335 new human diseases emerging between 1960 and 2004, running from avian influenza to Zika ("Epidemics and society", Snowden, 2020).
Since the 1990s, public health experts have warned with increasing urgency about the potential for a pandemic ("Emerging infections: microbial threats to health in the United States," U.S. Institute of Medicine, 1992).
In the early 2000s, both the U.S. Central Intelligence Agency and the RAND Corporation highlighted the threat to national security and wellbeing ("The global threat of new and re-emerging infectious diseases", RAND, 2003).
In September 2019, the World Health Organization published the first annual report of the Global Preparedness Monitoring Board, created to press policymakers to prepare for and mitigate health threats.
Presciently titled "A World at Risk", the report warned about the growing threat from "epidemics or pandemics that not only cause loss of life but upend economies and create social chaos".
In recent decades, public health experts have planned grimly for a pandemic of a new unknown "Disease X", examining its likely impact on health and the economy, and war-gaming responses and control strategies.
(Disease X represents the knowledge that a serious international epidemic could be caused by a pathogen currently unknown to cause human disease, according to the WHO).
Outbreaks of avian influenza, Ebola, Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) all came to be regarded as dress rehearsals for the big one.
At the time, each outbreak generated an upsurge in interest and funding from policymakers, but as the emergency receded and fear subsided, governments and citizens returned to business as usual.
"Each microbial challenge has been followed by a period of frenetic activity at every level, internationally and nationally, but has concluded with a lapse into forgetfulness," said historian Frank Snowden.
Even if an effective vaccine can be developed to control COVID-19, the threat of future epidemics, including Disease X, will not go away.
The coronavirus should therefore prompt policymakers to reconsider the underlying factors that contributed to its rapid transmission, including the structure of cities and megacities and their public health implications.
The coronavirus has revealed a set of vulnerabilities around urbanisation, overcrowding, poverty, uneven healthcare services, public transportation and aviation, that demands a deeper rethink.
Coronavirus should serve as a warning. Future epidemics, including Disease X, could be even more transmissible and/or lethal.
Ultra-dense and hyper-connected cities have become fragile or brittle, to use terms familiar to risk managers and emergency planners ("Brittle power: energy strategy for national security", Lovins, 1982).
The challenge is to re-imagine and re-engineer them to make them more resilient, while retaining features that make them economically successful and attractive for their inhabitants.
Megacities and other primary cities have been the most economically successful areas of modern economies and a huge driving force for prosperity, with some, albeit limited, spillovers to neighbouring regions.
Cities have significantly higher output per head, higher incomes, generate a disproportionate share of technological innovation, and are more energy efficient than less-urban and rural areas.
In 2017, London's economic output per head was 77% above the national average and more than double most other regions of Britain, an analysis of data from the U.K. Office for National Statistics showed.
At the same time, London's energy consumption, was far below average, mostly because of its heavy reliance on public transport systems, including buses as well as suburban and underground rail.
London's energy consumption for transport was around 3,100 kilowatt-hours per person in 2017, less than half of that used in the neighbouring regions of the Southeast (7,700 kWh) and Eastern England (8,100 kWh).
London's transport has been becoming more efficient faster than any other region, with energy use per capita falling by 26%, compared with 13% in the Southeast and just 7% in Eastern England, between 2007 and 2017.
For urban enthusiasts and climate campaigners, high-density cities have been a success story, generating prosperity while reducing energy intensity and curbing carbon emissions.
But the dark side of that success has been increased crowding in residential accommodation, workplaces, social areas and on public transport systems.
The critical question is whether cities, especially megacities, can be re-engineered to reduce overcrowding and opportunities for epidemic transmission, while retaining much of their productivity and energy efficiency.
Can cities be made less overcrowded to reduce transmission risks while maintaining their productivity and energy efficiency advantages
Can cities be re-engineered through changes in land use, spatial planning and density controls, or via changes in behaviour and the way existing assets are used
Can highly dense, interconnected cities be better protected through enhanced disease surveillance and other public health measures
Finally, is there a case for dispersing more economic activity and population, or at least new growth, away from megacities and other primary cities to secondary cities and smaller urban areas
INERTIA VERSUS RUPTURE
Re-engineering cities involves tough tradeoffs for policymakers, business leaders, real estate investors and individual citizens.
How far cities change in the aftermath of the coronavirus, and in anticipation of future epidemics, depends on the balance between two forces – inertia versus rupture.
Powerful vested interests are already pushing for restoration of the pre-epidemic status quo in the distribution of residential accommodation, commercial real estate, central work patterns, commuting and transport.
At the same time, cities and entire countries have been subject to a shock that ranks among the largest social and economic disruptions in a century, which creates intellectual, social and policy space for a significant rethink.
How much cities change or stay the same depends on how far the shock overcomes the inertia.
(Editing by Barbara Lewis) ((email@example.com))