Picture This: Air pollution affecting Covid fatality in India?

Studies have found that exposure to air pollution can lead to severe cases of Covid-19. A Harvard study also found that people who live in regions with higher air pollution are more likely to die from the disease than those who live in less polluted regions.

The second wave of the coronavirus pandemic wreaked havoc in India in April, and May 2021. Was there a relationship between PM 2.5 readings in different cities (signifying levels of air pollution) and Covid-19 fatality rate? The picture above looks at 22 cities across India to see if cities with high PM 2.5 readings also had high Covid fatality rates. These are 22 cities with population more than 1 million for which we have data for both the variables.

The India map on the left shows the PM 2.5 readings for these 22 cities while the map on the right shows the fatality rate. The PM 2.5 data is the annual average value of PM 2.5 readings for a city in 2019, as reported in the Central Pollution Control Board Report 2019-20. The fatality rate is as on 7^th July 2021.

Delhi has high air pollution with PM 2.5 reading of 141 and high fatality rate of 1.74 percent but Mumbai has much lower air pollution levels with PM 2.5 reading of 40 but it has an even higher fatality rate of 2.14 percent. Cities like Chennai, Ahmedabad, Bhilai, and Madurai have low levels of air pollution but reported high Covid fatality rates.

We therefore do not observe a clear relationship between pollution levels across cities and their Covid-19 fatality rate.

We must note that Covid caseload or fatality rate may be influenced by more than one factor. While exposure to air pollution may impact fatality rate, other factors like availability or lack of health care facilities may matter more depending on the context.