“Pollution-afflicted areas will have a higher incidence of COVID,” said Dr. Kumar, the chest surgeon. “And once this population gets COVID, they then have a higher chance of mortality.” Up until now, people in New Delhi this year had been spoiled in terms of breathable air. When a coronavirus lockdown in the spring shut down many industries and kept cars off the road, Delhi’s skies turned a miraculous blue. It was the cleanest air in decades, and at night, residents felt as if they were being treated to a star show. Constellations that hadn’t been seen for years shone above the apartment blocks. But that has become a dim memory. The sky is back to its usual hazy brown, and the city now smells of smoke.