Due to uncertainty over the effect the Oxford/AstraZeneca vaccine has on hospitalizations, Abdool Karim, head of South Africa’s Covid-19 Advisory Board, said the country is pausing the wide spread rollout of the vaccine in favor of a “stepped approach” –– giving shots to 100,000 people to study its impact on severe disease and hospitalization.
“If we find that the hospitalization rates are below the threshold that we are looking at, then we can be confident that the vaccine is efficacious and maintains its efficacy against hospitalization,” Karim told CNN’s Becky Anderson. “And if so we can then proceed to continuing the rollout.”
However, he said the country would consider switching to other vaccines if there appears to be no effect on hospitalization rates. “If we find that the hospitalizations are substantially more than we anticipated, then we would have to stop, take stock of where we are and perhaps switch to other vaccines,” Karim said.
Late Sunday, South African health officials said they're pausing the country's rollout of AstraZeneca's coronavirus vaccine after a study showed it offered reduced protection from the Covid-19 variant first identified there.
Early data released Sunday suggest two doses of the Oxford/AstraZeneca Covid-19 vaccine provided only "minimal protection" against mild and moderate Covid-19 from the variant first identified in South Africa.
The full study, which has not been released, included about 2,000 volunteers who were an average of 31 years old; about half received the vaccine and half received a placebo, which does nothing.
Karim noted that the study, which focused on young people, had a potentially wide range of effect. He noted the study overall found the vaccine to be 22% effective, however there were times it showed to be as high as 60% effective.
“What the study has created is some uncertainty about the efficacy of the AstraZeneca vaccine. So it's more about what the uncertainty is, rather than what [the study] actually shows,” Karim said.