What if Wuhan was not locked down?

On 23 January, China took an unprecedented step to contain a fast-spreading disease. What seemed brutal at that point turned out to be a model for other countries in their fight against the novel coronavirus. If Wuhan, the origin of the outbreak, was not locked down, covid-19 cases would have been at least 50% higher in other cities of China, suggests research.

Hanming Fang and others in a National Bureau of Economic Research paper estimate the effect of restricting human mobility in delaying the transmission of the novel coronavirus. To quantify the impact of the lockdown, they use inter- and intracity daily migration data from Baidu and the covid-19 infection data from the Chinese Centre for Disease Control and Prevention.

The authors find that the lockdown drastically reduced the inflow to Wuhan and outflow from Wuhan to other cities, and even movements within Wuhan.

This, in turn, played a significant role in reducing the transmission of virus to other parts of China and in confining the cases to Wuhan.

In the absence of the lockdown, the number of cases outside Hubei province would have been at least 65% higher and in Hubei province it would have been 53% higher. The authors point out that the gap in the official numbers and actual infections in Hubei reduced over time.

However, the spread of the virus in the initial days posed high risk of community spread. In such a scenario, the adoption of social distancing in other provinces helped delay transmissions via people who moved from Hubei to other provinces. Based on the model adopted by China, the authors suggest that identifying epicentres and implementing adequate social distancing measures will be crucial to contain infections and reduce fatalities.

Also read: Human Mobility Restrictions And The Spread Of The Novel Coronavirus (2019-Ncov) In China

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