A volunteer receives a COVID-19 test vaccine injection developed at the University of Oxford in Britain, at the Chris Hani Baragwanath hospital in Soweto, Johannesburg, South Africa. People on six continents are testing experimental shots as the race for a COVID-19 vaccine enters a defining summer. (AP Photo/Siphiwe Sibeko)
The World Health Organization says it has a leading candidate when it comes to a COVID-19 vaccine. Inovio Pharmaceuticals says it has some positive results from one of their clinical trials.