Around half of South Africa’s population may have already been infected by a coronavirus, a figure far higher than the documented tally, a study and analysis of death figures suggest.
Samples taken from almost 5,000 blood donors across four South African provinces in January showed that between 32 and 63 percent had antibodies to the coronavirus.
The figure compares with clinically confirmed case rates of just two to three percent, according to South African research that was released online last week, but has not yet completed peer review.
The numbers could be understated, said lead investigator Marion Vermeulen of the South African National Blood Service.
People with confirmed or suspected Covid-19 are unable to donate blood for 14 days, and therefore less likely to be sampled, she explained.
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.
Officially, South Africa has recorded close to 1.5 million coronavirus cases, of which just under 48,500 have been fatal — the highest toll in Africa.
“Many people who are vulnerable to Covid have a lot of other conditions… so the cause is always hard to define.”
It is also easy to misrecord deaths at the height of a pandemic, when “medical staff (are) running around trying to save lives”, he added.
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 percent of the country’s second wave of cases, scientists say.
The country kicked off its long-awaited inoculation campaign on Wednesday with jabs developed by US pharmaceutical giant Johnson & Johnson.