JOHANNESBURG – South Africa should know its true toll from the coronavirus pandemic within a few weeks, the government’s chief medical adviser says, as the country prepares to almost fully reopen its economy after bringing the first surge in cases under control.The official death toll from COVID-19 is more than 15,700 but the real number is likely more than 30,000 when deaths not recorded at hospitals are taken into account, Salim Abdool Karim, epidemiologist and chairman of the government’s COVID-19 advisory committee, told The Associated Press in an interview.He hopes that a nationwide survey for the presence of antibodies to the virus will show results soon.