Until earlier this year, Zaidi Recyclers was a thriving business processing waste paper which it exported to customers in China and India, earning it around $37,000 in monthly sales.

New orders dried up, however, as country after country imposed lockdowns to stop the spread of the new coronavirus, reducing global trade to a trickle.

But the plant in Tanzania’s port city of Dar es-Salaam has traded paper for plastic bottles and started making anti-coronavirus face shields that are being snatched up by hospitals and health centres nationwide. In recent weeks the business has made 6,000 units that sell for around two dollars each.