Set in a dry and dusty landscape, Mongo is a town of 40,000 people, in Chad, a landlocked country in central Africa. Average life expectancy, at 51, is about 30 years lower than in the UK.

Chad, a country of nearly 18 million people, has been reeling from political turmoil before and after a controversial presidential election that resulted in Deby Itno’s victory. He had led the ...