“Once you take the cork out of the bottle, I’m not sure that it’s particularly easy for you to get it back,” said Anthony Cox, a vaccination safety expert at the University of Birmingham, England.
South Africa immediately copied the American break in Johnson & Johnson vaccinations and enraged doctors who still call for gunshots, especially in remote parts of the country. In February, health officials dropped the AstraZeneca vaccine there because of its limited effectiveness against a dangerous variant.
To date, only half of 1 percent of the population is vaccinated and only 10,000 shots are fired a day. At this rate, it could be weeks, if not longer, for a single rare case of blood clotting to occur, said Jeremy Nel, an infectious disease doctor in Johannesburg. He was dismayed by the decision to pause the shooting, given the risk of building confidence in vaccines in a country where two-fifths of the population say they don’t intend to vaccinate.
“The slower you go, the more that failure is measured in terms of death,” said Dr. Nel. “Even if you are late by a week, there is a non-trivial chance that will cost your life.”
The solution in many European countries – stop using apparently riskier vaccines in younger people who are less at risk of Covid-19 – would not be practical in Africa, where the average age in many countries is under 20.
Further restrictions would tighten the hurdles for Covax, including a lack of funding for any part of vaccination programs beyond doses at airports.
Mali, in West Africa, has administered 7 percent of the AstraZeneca doses administered by Covax. Sudan in East Africa has given 8 percent of the doses it has received.