South Africa rolls out the continent's first coronavirus vaccine trial this week, the university leading the pilot said Tuesday, as the country grapples with the highest number of cases in Africa.

The vaccine, developed by the Oxford Jenner Institute, is already being evaluated in the United Kingdom, where 4,000 participants have signed up for the trial. South Africa has set out to vaccinate 2,000 people with the vaccine known as ChAdOx1 nCoV-19. Fifty of the candidates have HIV.

"We began screening participants for the South African Oxford 1 Covid-19 vaccine trial last week, and the first participants will be vaccinated this week," said University of Witwatersrand (Wits) vaccinology professor Shabir Madhi at a virtual press conference.

Brazil is planning its own pilot, while the United States is preparing to test another vaccine in a mass trial of up to 30,000 participants. Wits is collaborating with the University of Oxford and the Oxford Jenner Institute on the South African trial.

South Africa's coronavirus cases jumped to over 100,000 on Monday, while the number of deaths inched towards 2,000. Officials implemented a strict nationwide lockdown on March 27, just weeks after the virus first hit South Africa. But confinement measures are being gradually phased out to allow business to pick up and limit damage to an already ailing economy.

"As we enter winter in South Africa and pressure increases on public hospitals, now more than ever we need a vaccine to prevent infection by COVID-19," Madhi said, describing the vaccine trial as a "landmark moment".

South African health officials have also placed high hopes on dexamethasone, a generic anti-inflammatory drug found to reduce mortality among ventilated patients. "This is one of those medicines where we do have excellent local capacity," said Health Minister Zweli Mkhize in a statement last week.

South African pharmaceutical giant Aspen Pharmacare has said it was ready to scale up production of the steroid.