Around half of South Africa's population may have already been infected with the novel coronavirus, a study suggests.

Coronavirus in South Africa

Samples taken from almost 5,000 blood donors across four South African provinces in January showed that between 32 and 63 per cent had antibodies to the coronavirus.

The figure compares with clinically confirmed case rates of just 2 to 3 per cent, according to South African research that was released online last week, but has not yet completed peer review.

People with confirmed or suspected Covid-19 are unable to donate blood for 14 days, and therefore less likely to be sampled.

South Africa halts rollout of Oxford/AstraZeneca jab due to 'limited protection' as Britons face needing a third jab

Antibodies are a telltale of an individual's exposure to the virus, but not a confirmation that the person has fallen sick from it.

Most antibodies were detected in the Eastern Cape and KwaZulu-Natal provinces. Both were epicentres of South Africa's second infection wave when it started in December.

South Africa kicked off its long-awaited inoculation campaign on Wednesday with jabs developed by US pharmaceutical giant Johnson & Johnson.

The country has so far recorded close to 1.5 million coronavirus cases, of which just under 48,500 have been fatal -- the highest toll in Africa.

Steep estimates that South Africa's Covid-19 mortality stands around 0.4 per cent -- a figure derived from an Infection Fatality Rate published by London's Imperial College for modelling.

The South African variant of the coronavirus, which is more transmissible and more resistant to existing vaccines than its original form, accounts for some 90 per cent of the country's second wave of cases.