People wait outside a health center to get tested for COVID-19 in New Delhi, India, Thursday, Feb. 11, 2021. When the coronavirus pandemic took hold in India, there were fears it would sink the fragile health system of the world’s second-most populous country. Infections climbed dramatically for months and at one point India looked like it might overtake the United States as the country with the highest case toll. But infections began to plummet in September, and experts aren’t sure why. (AP Photo/Manish Swarup)