ALEXANDER WINNING and GEORGE OBULUTSA THE global vaccine distribution scheme COVAX aims to deliver 520 million COVID-19 vaccine doses to Africa this year, its managing director said, with supplies ramping up from September after delays caused by Indian export restrictions. Aurelia Nguyen told a news conference organised by the World Health Organization's Africa region that the scheme had delivered around 25 million doses to 44 African countries so far, but she was not happy with progress. In early March, the CEO of vaccine alliance Gavi, one of the organisations co-leading COVAX, had said the aim was to supply Africa -…