South Africa has suspended plans to inoculate its front-line health care workers with the Oxford-AstraZeneca vaccine after a small clinical trial suggested that it isn’t effective in preventing mild to moderate illness from the variant dominant in the country.
South Africa received its first 1 million doses of the AstraZeneca vaccine last week and was expected to begin giving jabs to health care workers in mid-February.
The disappointing early results indicate that an inoculation drive using the AstraZeneca vaccine may not be useful.
Preliminary data from a small study suggested that the AstraZeneca vaccine offers only “minimal protection against mild-moderate disease” caused by the variant in South Africa.
The variant appears more infectious and is driving a deadly resurgence of the disease in the country, currently accounting for more than 90 per cent of the Covid-19 cases, health minister Zweli Mkhize said Sunday night.
“The AstraZeneca vaccine appeared effective against the original strain, but not against the variant,” Mkhize said.
“We have decided to put a temporary hold on the rollout of the vaccine … More work needs to be done.”
The study, which hasn’t yet been peer-reviewed, involved 2,000 people, most of whom were young and healthy. The volunteers’ average age was 31.
“Protection against moderate-severe disease, hospitalisation or death could not be assessed in this study as the target population were at such low risk,” said a statement issued by Oxford University and the University of the Witwatersrand in Johannesburg.
Scientists will be studying whether or not the AstraZeneca vaccine is effective in preventing severe disease and death against the variant, Mkhize said.
Other vaccines have shown reduced efficacy against the variant, but have provided good protection from serious disease and death.
Public health officials are concerned about the South Africa variant because it contains a mutation of the virus’ characteristic spike protein, which is targeted by existing vaccines. South African officials say the variant is more contagious and evidence is emerging that it may be more virulent.