THE World Health Organization has warned the coronavirus pandemic could overwhelm strained public health systems in Africa. On Wednesday, the continent was approaching a million infections and around 21,000 deaths, according to a Reuters tally. Here are measures some countries are taking to curb the virus. SOUTH AFRICA With more cases than any other country on the continent, South Africa imposed a strict lockdown on March 27, closing borders and requiring most people to stay at home except for essential trips. The government also banned the sale of alcohol and cigarettes. The government in May allowed the re-opening of many…