The 21-day lockdown announced by the government may help bring down the number of Covid-19 cases in the country by 85 per cent, according to some number crunching done by researchers at Shiv Nadar University (SNU) in Greater Noida.

“We considered the optimistic scenario, where cases are isolated immediately in day 1 or 2 after showing symptoms. We assumed 80-90 per cent of population contributed to social distancing. In this optimistic scenario, the projected number of symptomatic cases can decline by nearly 85 per cent at day 20 from the beginning of the lockdown (3,500 against 30,790) and deaths (105 against 619) as well,” said mathematician Samit Bhattacharyya and biologist Naga Suresh Veerapu of SNU.

Although, they did their mathematical modelling before the Tablighi Jamaat function at Nizammudin emerged as a super spreading event.

Surge expected

The SNU experts, however, said that they expect a surge in Covid-19 cases once the lockdown is lifted. “The 21-day lockdown only helps buy time to prepare ourselves for a better fight against corona. All measures that may limit opportunities for the virus to spread must be continued, which not only limit any individual’s infection hazard, but also protect the entire community,” they said.

All measures that would help flatten the Covid-19 curve such as avoiding large gatherings, 14-day quarantine for suspected cases of infection, systematic surveillance, continued work from home for employees and expanded testing to identify the infections should continue beyond April 14, the SNU faculty said.

At the beginning of the lockdown, India was in the second phase of the Covid-19 outbreak, ie, transmission to close contacts and there was no evidence for community transmission, but it has appeared sliding into the third phase of the outbreak.

Without any intervention, India could have embraced about 5,000 and 30,790 symptomatic cases in the next 10 days and 20 days, respectively. “The projected number of cases can reach approximately 2,70,360 and deaths, 5,407, by day 40, in the absence of an intervention,” they said.