JOHANNESBURG (AP) – South Africa is considering giving a COVID-19 vaccine that is still in the testing phase to health workers after the rollout of another shot was suspended, indicating preliminary data is ineffective to to prevent mild to moderate disease of the variant that is dominant in the country.
The country is scrambling to come up with a new vaccination strategy after discontinuing the use of the AstraZeneca vaccine – which is cheaper and easier to deal with than others and which many had hoped would be necessary to combat the pandemic in developing countries. Among the possibilities being considered: mix the AstraZeneca vaccine with another and give Johnson & Johnson’s single-dose vaccine, which is nowhere authorized to be used, to 100,000 health professionals while monitoring its effectiveness against the variant.
South Africa’s vaccination strategy is being monitored worldwide because the variant that was first detected here and is now dominant is spread in more than 30 countries. Officials say this form of the virus is more contagious, and there is evidence that it may be more virulent; recent studies have also shown that it can infect people who have survived the original form of the virus.
After a second upsurge, cases and deaths in South Africa have recently started to decline, but it is still fighting one of Africa’s most serious outbreaks, with more than 46,000 deaths. It is worrying that another rise will come in May or June when the Southern Hemisphere enters its winter.
So far, early results from trials of the Johnson & Johnson vaccine have shown that it offers less protection against the variant than the original disease, but that it is still very effective in preventing serious and fatal cases, according to Dr Glenda Gray, director of the South Africa Medical Research Council, which led the South African part of the global trial. A Novavax vaccine candidate showed similar results.
‘We can not wait. We already have good local data, ”said Gray, emphasizing that clinical trials show that it is safe. She added that South Africa was urgently considering plans to ‘carry it out and evaluate it in the field’.
“Our scientists need to get together and quickly find out what approach we are going to use,” Health Minister Zweli Mhkize said on Sunday night, announcing that the use of the AstraZeneca vaccine, which is currently the only one in South Africa, has been suspended. Deliveries from others, including those made by Pfizer and BioNTech, are expected soon.
The suspension derailed South Africa’s vaccination plans just one week after the country received its first 1 million doses of vaccine. This came after the early results of a small clinical trial showed that the shot does not cause mild to moderate cases of COVID-19 in young adults, according to an announcement from the University of the Witwatersrand, which conducted the test.
The AstraZeneca study involved 2,000 healthy volunteers with a mean age of 31 and showed that only 22% were protected against mild to moderate cases of the disease.
Experts believe that the vaccine can still prevent serious diseases – and it will help a lot to slow down the pandemic and prevent hospitals from being overwhelmed with patients.
“Vaccines that are effective against the more serious forms of disease may not affect milder forms. Therefore, there is optimism that serious diseases can still be prevented by vaccines,” said Peter Openshaw, a professor of experimental medicine at Imperial College London. , said.
But the results were disappointing enough that South African officials decided to postpone the vaccination, which was supposed to put health workers at the forefront in mid-February.
The pre-study was not judged by the peer – the gold standard in scientific studies – but was still a reality test, ‘said Professor Shabir Madhi, who conducted the trial. “We were euphoric. We need to recalibrate our expectations. ”
Now the country wants to shift gears. It can eventually continue with the administration of at least one dose of AstraZeneca in the hope that it will protect against serious diseases and death of the variant. It is also considering combining the shot with one from another vaccine. Most of the vaccines tested require two doses; Johnson & Johnson is an exception.
An experimental study began in Britain last week – the first of its kind worldwide – to test whether doctors can safely mix the doses of the AstraZeneca vaccine and match the survey conducted by Pfizer and BioNTech.
A further complication is that the doses of AstraZeneca in South Africa have an expiration date for April, which makes it difficult to administer two doses within such a short period of time.
Last week, Sarah Gilbert of Oxford University, who helped develop the AstraZeneca vaccine, said researchers were currently modifying their vaccine by inserting a genetic sequence from the new variant.
South African experts conducted clinical trials on the effects of the variant known as B.1.351. This variant quickly became more than 90% here.
The variant has lowered the protection level of virtually all of the vaccines, but most vaccines show satisfactory efficacy to protect against serious cases and death caused by the version, Madhi said. Trials of the Novavax vaccine, for example, have shown reduced but still good protection against the variant, he said.
“It’s not all ruin and gloom … we do have vaccinations that work,” Madhi said.
Still, he added, ‘This virus will probably be with us for the rest of our lives. It is unlikely that it will be eradicated soon. ”