How contagious is the coronavirus? Here’s what ICMR math suggests

For those unsure about where India stands vis-a-vis the coronavirus contagion, here’s help based on data from Indian Council of Medical Research.

According to latest government data, India’s case count was at 492, with nine deaths being reported. From just a 100 cases on March 15, India’s case count shot up almost 5 times in just 9 days through March 23.

In a report released on Monday, the ICMR said, strictly implementing social distancing measures such as home quarantine of symptomatics and suspected cases will reduce the overall expected number of cases by 62% and the peak number of cases by 89%, thus “flattening” the curve and providing more opportunities for interventions.

The ICMR also warned that introduction of community transmission of coronavirus cases would take anywhere from 20 days to a few months to be visible.

Under the most optimistic scenario, the study assumed that one infected person would only infect 1.5 others. Under the most pessimistic one, 4 people or more could be infected from one positive patient.

The report has also suggested that India ranks 17th among the countries at the highest risk of importation of COVID-19 through air travel. The probability of an infected air traveller to come to India as the final destination was 0.2%, with the highest relative import risk in Delhi (0.064%) followed by Mumbai, Kolkata, Bengaluru, Chennai, Hyderabad and Kochi.

It also reiterated that “identifying at least 75% of the asymptomatic individuals was needed, in order to delay the within-country outbreak by an appreciable amount.” Additional detection of 90% asymptomatic individuals would delay the average time to epidemic by 20 days.

The report also suggested that the duration of the outbreak would be much lower in the scenario of ‘no intervention’ compared to ‘intervention’.

The government has maintained that the third stage, community transmission, has not yet begun in the country. Complete lockdown has been imposed on most of the country, with rail and bus services being suspended till March 31. This midnight onward, even domestic flights will be suspended, allowing for only cargo to be transported.

As per WHO data, almost 4 lakh cases have been reported globally, including 81,171 cases from China and 63,927 in Italy.