How virus could shape planning of future megacities

The Covid-19 pandemic has exposed the vulnerability of densely populated cities with crowded accommodation and public transportation systems to the transmission of airborne viruses.

Even if an effective vaccine can be deployed, the outbreak is unlikely to be the last, with future epidemics of coronavirus, or other airborne viruses, likely in the next few decades.

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," US Institute of Medicine, 1992).

In the early 2000s, the US 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 Organisation 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.