Megacities

The seven deltas alone host 14 of the world's 33 megacities, including Bangkok, where the experts are gathered this week, parts of which are sinking by 2 centimeters a year.

The developing world is home to densely populated megacities that may be tinderboxes of viral transmission.

The developing world is home to some densely populated megacities that may be tinderboxes of viral transmission. But it also encompasses large rural areas where social distancing is not a public health recommendation, it's a way of life.