Medical experts have warned that the toxic pollution that envelops New Delhi annually will lead to more coronavirus deaths. By 7am in mid-November, the air in New Delhi smells of acrid smoke and the sky is covered by a grimy brown haze. The air quality is comparable to Beijing on its most polluted days, and will deteriorate further as the temperature and winds drop, blanketing the national capital region in smog for months.

Farm stubble burning, vehicle emissions and the encroaching winter have pushed the city’s air quality index into the severe category at the same time that more than 5,000 coronavirus cases are being confirmed daily. Doctors said that the pandemic has exposed how pollution has made populations more vulnerable to disease, warning that a flood of coronavirus patients with severe symptoms, aggravated by the hazardous air, could overwhelm India’s hospitals.

“There is a definitive association between Covid mortality and air pollution,” said Chandrakant Lahariya, an epidemiologist in New Delhi. “More people with respiratory diseases will develop symptoms.” Long-term exposure to air pollution is linked to 15 per cent of “potentia lly avoidable” Covid-19 deaths , said researchers behind a new study published in the journal Cardiovascular Research.

We already have a respiratory virus that we don’t understand, now we are adding tons and tons of poison in the air. We are going to experience an unprecedented public health catastrophe

Jai Dhar Gupta, Nirvana Being

“Air pollution is acting like a super spreader for Covid,” said Thomas Miinzel, a co-author and cardiologist at Johannes Gutenberg University in Mainz, Germany. Hesaid that particulate matter made lungs more susceptible to coronavirus infection. India’s pollution season poses a perennial problem for authorities who have failed to develop a successful strategy to curb emissions. Every year, smog blankets north India, home to 10 of the 15 most polluted cities in the world.

Last year, when the index hit 1,000 – it should be below 50 – Delhi state chief minister Arvind Kejriwal said the capital had “turned into a gas chamber”. Mr Kejriwal’s government last month launched a “Green War Room”, which is responsible for monitoring pollution levels in the national capital region and deploying enforcement agencies to crack down on environmental offences such as garbage burning and illegal industrial activity.

One of the war room’s early recruits was Aashima Arora. Ms Arora left her well-paid job at Citibank to join the Air Pollution Action Group, determined to tackle the toxic air that kills more than 1m Indians every year.