One third of the world’s population does not have access to a basic toilet. On #WorldToiletDay, they are telling us, #WeCantWait. Isabel Medem and David Auerbach are doing something about that. November 19 is World Toilet Day. Why? Because globally, about 2.4 billion people, about one-third of the world’s population, do not have access to a basic toilet. Sanitation-related illnesses kill over a thousand children per day. This problem is compounded by the concentration of informal housing in urban setting. This week I spoke to two change makers who are doing something about hygienic sanitation, David Auerbach of Sanergy and Isabel Medem of X-Runner Ventures. Social Entrepreneurship Ideas Sanergy David’s…