The spread of the coronavirus in Africa has lagged much of the globe, but it’s picking up speed. Health authorities say the highly infectious virus poses a heightened threat to countries with weak healthcare systems and especially to vulnerable populations of refugees, migrants and forcibly displaced people.

The continent passed a milestone of 750,000 confirmed cases, Reuters reported Wednesday. The news service, using government and World Health Organization data, tallied 751,151 cases, 15,721 deaths and 407,461 recoveries. It noted that Africa had 500,000 confirmed cases on July 8.