Covid-19: Mathematicians, too, chip in to decode the pandemic

Away from the field of actual action, many mathematicians and physicists across the world are working overtime to ascertain how the novel coronavirus (COVID-19) pandemic overwhelmed healthcare systems in the worst public health crisis since the 1918 Spanish flu.

These quantitative scientists are using mathematical models to project a range of things -- such as the number of Covid-19 infections that can be expected in a country, region or a city with and without various measures initiated by the authorities and how many ICU beds, ventilators and other critical pieces of health infrastructure are required to deal with the problem.

“The most important thing is to flatten the curve,” said Samit Bhattacharya, a mathematical modeller and an associate professor of mathematics at the Shiv Nadar University in Greater Noida. By ‘curve’ Bhattacharya means the sudden spike in hospital admissions requiring emergency care that happen during infectious disease outbreaks. Bhattacharya, who has been studying how infectious diseases spread for more than a decade, is currently part of an international team of researchers that is trying to understand how measures taken by governments in different countries such as Belgium, Brazil, Canada, India, the US and a few African countries would help reduce the spread of the Covid-19 infection.

“We have so far identified 500-odd positive cases in the country. I suspect there are many more people who carry the pathogen. Maybe close to 10,000. These potential carriers can spread the infection further. The modelling can help project best-case and worst-case scenarios, helping the authorities to know whether sufficient action has been taken or whether there is need to deepen it further,” he said.

“Social distancing and lockdowns are very important as we know very little about this virus and there are no known ways to contain its effect,” the Shiv Nadar University researcher said.

As per Bhattacharya’s calculations, the virus, in the initial stages of the outbreak in Wuhan, had a reproductive number of 2.2 to 3. Reproductive number indicates the number of people infected on average by an infected person. If the number of reproductions is greater than one, the epidemic spreads exponentially. To bring any epidemic under control, the reproductive number needs to be brought down to less than 1. Measures such as social distancing, lockdowns, as well as using masks and proper handwash can help bring down the reproductive number.

According to him, the biggest worry could be the infection getting to rural parts of the country, where public health infrastructure is almost non-existent. “With the lockdown in urban areas, a large number of migrant labourers have gone back to their villages. We are not sure how many of them carried the pathogen with them. If they did, it is a disaster in the making in those impoverished rural settings,” Bhattacharya said.

Gautam Menon, professor of physics and biology at Ashoka University, near Sonepat, is another Indian researcher trying to use mathematical modelling to understand the impact and severity of the Covid-19 pandemic on the Indian population. His model is still a work in progress.

COMMENT NOW