Scientists at the World Health Organization (WHO) say nearly a quarter of a billion people in Africa could contract coronavirus within the first year of the pandemic.
But they think more people will survive it than in the US and Europe because so many Africans are young.
Their study, published in BMJ Global Health, says between 150,000 and 190,000 Africans could die from Covid-19. This is higher than previously predicted.
It says 5.5 million people would need hospital treatment, overwhelming services already struggling to treat malaria, tuberculosis and HIV.
Coronavirus has been relatively slow to spread in Africa but has already taken hold in camps for displaced people in South Sudan.