Coronavirus lockdown and emergency averted 7 lakh cases in China: Study

China prevented nearly 700,000 covid-19 infections because of the unprecedented lockdown of the epidemic epicentre Wuhan city and the central Chinese province of Hubei, a new international study estimates.

The lockdown measures in Wuhan were aided by national emergency measures like the shutting down of intra-city public transport, the closing of entertainment venues and the banning of public gatherings, it said.

Hundreds of thousands of covid-19 cases were avoided because of the measures despite 4.3 million travelling out of Wuhan between January 11 and January 23, the day the lockdown was announced, possibly ushering in the largest quarantine measure in history.

The study named, “The Impact of Transmission Control Measures in the first 50 Days of the Epidemic,” was compiled by more than 20 scientists from institutes in China, the US and the UK.

It analysed past and current travel data and information related to the infection numbers to come to the conclusion.

“As there is currently neither a vaccine nor a specific drug treatment for covid-19, a range of public health (non-pharmaceutical) interventions have been used to control the outbreak. In an attempt to prevent further dispersal of covid-19 from its source, all transport was prohibited in and out of Wuhan city from 10:00 am on 23 January 2020, followed by the whole of Hubei Province a day later,” the study said.

The study says that in terms of the population covered this appeared to be the largest attempted quarantine (movement restriction) event in human history and analyses the efficacies of the preventive measures.

“Among interventions investigated here, the most effective were suspending intra-city public transport, closing entertainment venues and banning public gatherings,” it said.

It states that the national emergency response delayed the growth and limited the size of the covid-19 epidemic and, by 19 February (day 50), had averted hundreds of thousands of cases across China.

The researchers carried out a quantitative analysis of the impact of travel restrictions and transmission control measures during the first 50 days of the covid-19 epidemic in China from December 31 to February 19.

This period coincided with the 40 days of the Chinese New Year (CNY) festival holidays -- 15 days before the CNY on January 25 and 25 days afterward.

During the CNY holiday travel in 2017 and 2018, on an average of 5.2 million people from Wuhan city travelled out during the 15 days before the CNY.

“In 2020, this travel was interrupted by the Wuhan city shut down, but 4.3 million people travelled out of the city between January 11 and the implementation of the ban on January 23,” the study notes.

In 2017 and 2018, travel out of the city during the 25 days after the Chinese Lunar New Year (or CNY) averaged 6.7 million people each year.

“In 2020, the travel ban prevented almost all of that movement,” the researchers said.

The researchers added that without the Wuhan travel ban or the national emergency response, there could have been 744,000 (± 156,000) confirmed covid-19 cases outside Wuhan by 19 February, day 50 of the epidemic.

In summary, this early analysis suggests that transmission control (non-pharmaceutical) measures initiated during Chinese Spring Festival (or CNY) holiday, including the unprecedented Wuhan city travel ban and the Level 1 national emergency response delayed the growth and limited the size of the 177 COVID-19 epidemic in China, the study said.

Interestingly the study suggests that urbanization and modernization of transport could have actually helped in spreading coronavirus.

“Urbanisation and the development of rapid transport systems in China probably accelerated the spread and magnified the challenge of controlling covid-19, as indicated by the comparatively slow dispersal of pandemic influenza H1N1 in 2009,” the study said.

“In addition, the covid-19 epidemic began just before the period of intense travel during the Spring Festival (or CNY) holiday. Nevertheless, the Wuhan city travel ban provided extra time to implement transmission control measures in other parts of China and, once established, these were an additional powerful force in curtailing and reversing the epidemic,” it said.

The yet to be peer-reviewed study was published by medRxiv, founded by the US-based Cold Spring Harbor Laboratory (CSHL), a non-profit research and educational institution, Yale University, and BMJ, a global medical knowledge provider.

(eom)