JOHANNESBURG (AP) – South Africa is considering giving health professionals a COVID-19 vaccine that is still in testing phase after suspending the rollout of another shot that preliminary data indicated is ineffective to mild to moderate disease of the dominant variant is preventable in the country.
The country is struggling to come up with a new vaccination strategy after it discontinues use of the AstraZeneca vaccine – which is cheaper and easier to handle than others and which many had hoped would be crucial to fighting the pandemic in developing countries. Among the options being considered: mixing the AstraZeneca vaccine with another vaccine and giving Johnson & Johnson’s single-dose vaccine, which has not yet been approved for use, to 100,000 health professionals while ensuring its efficacy against the variant is checked.
South Africa’s vaccination strategy is being watched worldwide as the variant that was first discovered and is now dominant is spreading in more than 30 countries. Officials say this form of the virus is more contagious, and there is some evidence that it may be more virulent; recent studies have also shown that it can infect people who survived the original form of the virus.
After a second wave, cases and deaths in South Africa have recently started to fall, but it is still battling one of Africa’s worst outbreaks, killing more than 46,000. There is concern that there will be another peak in May or June, when the land in the Southern Hemisphere enters winter.
So far, early results from trials with the Johnson & Johnson vaccine have shown that it offers less protection against the variant than the original disease, but is still very effective at preventing serious and fatal cases, said Dr. Glenda Gray, director of the South Africa Medical. Research Council, which led the South African portion of the global trial. A candidate vaccine for Novavax has shown similar results.
‘We can not wait. We already have good local data, ”said Gray, emphasizing that clinical studies show it to be safe. She added that South Africa is making urgent plans to “roll it out and evaluate it in the field.”
“Our scientists need to get together and quickly figure out which approach we are going to use,” said Health Minister Zweli Mhkize Sunday evening, announcing the suspension of the use of the AstraZeneca vaccine, which is currently the only one available in South Africa. . Deliveries from others, including those from Pfizer and BioNTech, are expected shortly.
The suspension messed up South Africa’s vaccination plans just a week after the country received its first 1 million doses of the vaccine. It came after the initial results of a small clinical trial showed that the injection could not prevent mild to moderate cases of COVID-19 in young adults, according to an announcement from the University of Witwatersrand, which conducted the test.
The AstraZeneca study involved 2,000 healthy volunteers with a mean age of 31 years and showed that only 22% were protected against mild to moderate cases of the disease.
Experts say the vaccine can still prevent serious illness – and that could slow the pandemic significantly and prevent hospitals from being overwhelmed with patients.
“Vaccines that are effective against the more severe forms of disease may not affect milder forms, so there is optimism that serious illnesses are still prevented by vaccines,” said Peter Openshaw, a professor of experimental medicine at Imperial College London. .
But the results were disappointing enough that South African officials decided to delay the introduction of the vaccine, which would be given to primary care health workers from mid-February.
The preliminary study was not peer-reviewed – the gold standard in scientific studies – but was still “a reality check,” said Professor Shabir Madhi, who led the trial. ‘We were euphoric. We need to realign our expectations. “
Now the country wants to switch. It may eventually proceed to administer at least one dose of AstraZeneca in the hope that it will protect against serious illness and death from the variant. It is also considering combining the injection with an injection from another vaccine. Most vaccines being tested require two doses; Johnson & Johnson is an exception.
An experimental study began last week in Britain – the first of its kind worldwide – to test whether doctors could safely mix and match doses of the AstraZeneca vaccine with the injection of Pfizer and BioNTech.
An additional complication is that AstraZeneca doses in South Africa have an expiration date in April, making it difficult to administer two doses in such a short period of time.
Last week, Sarah Gilbert of the University of Oxford, who helped develop the AstraZeneca vaccine, said researchers are currently modifying their vaccine by inserting a genetic sequence from the new variant.
South African experts have conducted clinical studies on the effects of the variant, known as B.1.351. That variant quickly became more than 90% dominant here.
The variant has lowered the level of protection afforded by virtually all vaccines, but most vaccines have satisfactory efficacy in protecting against severe cases and death caused by the version, Madhi said. For example, trials with the Novavax vaccine showed reduced but still good protection against the variant, he said.
“It’s not all doom and gloom… we have vaccines that work,” Madhi said.
Still, he added, ‘This virus will likely be with us all our lives. It is unlikely to be eradicated anytime soon. “