Sikelela Mamba has had HIV for about 15 years, and it’s never really troubled him. The pills cost him nothing, and he’s never experienced any stigma or discrimination. “HIV is just like any other disease,” said the vegetable farmer from Eswatini, now in his 60s.

It’s Mr Mamba’s diabetes that terrifies him. For three or four months during a nationwide drug shortage, the local clinic had to ration his medicines, and he couldn’t afford to buy the rest. His blood sugar climbed dangerously high; he could do little but wait.

Mr Mamba knows HIV will not kill him. But he is less sure about diabetes.

Few places have been hit harder by HIV than Eswatini, a small landlocked country sandwiched between South Africa and Mozambique, the last absolute monarchy in Africa.…