Mumbai's Dharavi offers a rare glimmer of hope with new infections shrinking, thanks to an aggressive strategy that focused on "chasing the virus, instead of waiting for disaster", according to city official Kiran Dighavkar.The sprawling slum has long been a byword for the financial capital's bitter income disparities -- with Dharavi's estimated one million people scraping a living as factory workers or maids and chauffeurs to Mumbai's well-heeled residents.With a dozen people typically sleeping in a single room, and hundreds using the same public toilet, authorities realised early that standard practices would be of little use."Social distancing was never a possibility, home isolation was never an option, and contact tracing was a huge.