India, Dec. 17 -- The description may be cliched, but it remains apt - Delhi in winter turns into a gas chamber, leaving the elderly, children, and the ill with nowhere to turn. When doctors recommend leaving the city as treatment, it is a damning indictment of governance. As Delhi's Air Quality Index (AQI) hovers around the 400 mark, the national capital once again finds itself in the grip of a public health emergency, though a routine one. Year after year, Delhiites have become so used to it that hardly any marches or placards are seen protesting on the streets. On Monday, the city recorded an average AQI of 427 - its third consecutive day in the 'severe' category - before marginally improving to 381 on Tuesday morning but still categoris...