Johannesburg, South Africa
A health worker holds a COVID-19 sample collection kit of a vaccine trials' volunteer at the Wits RHI...
A health worker holds a COVID-19 sample collection kit of a vaccine trials' volunteer, after they were tested for the coronavirus disease and take part in the country's human clinical trial for potential vaccines at the Wits RHI Shandukani Research Centre in Johannesburg, South Africa, August 27, 2020. Picture taken August 27, 2020. REUTERS/Siphiwe Sibeko