The director of the Africa Centres for Disease Control and Prevention is raising the vaccination target he believes is needed to provide widespread protection against Covid-19 on the continent, citing the more infectious Delta variant now present in 32 countries.

Africa CDC Director John Nkengasong told reporters that health officials once estimated at least 60 per cent of Africa’s population of 1.3 billion people needed to be vaccinated to achieve so-called herd immunity.

Nkengasong says he now thinks the proportion should be “in excess of 70pc to 80pc”. Even at that level, he said, “are we going to get to herd immunity? I doubt that notion is relevant anymore.”

“Things will get more challenging before they get better,” Nkengasong said, according to AP.