The director of Tanzania’s tuberculosis programme, Said Egwaga, holds out a handful of the indigestibly large, brightly coloured tablets that his patients are required to take each day. Add in the anti-retroviral drugs for the many who are also infected with HIV, he jokes, and “it’s a full meal in itself ”.

But one problem is that many of those with TB – an ancient scourge that still kills 1.7m people globally every year – do not eat regular meals. Many suffer initially from the disease of poverty; even if they can afford the regular trips from remote rural areas to a clinic for diagnosis and treatment, they do not have the nutrition essential to assist their recovery.