AstraZeneca vaccine doesn’t protect well against South Africa variant, early trials show

astrazeneca vaccine south africa
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The AstraZeneca vaccine, previously heralded as an important tool in fighting the global COVID-19 pandemic, is now having its distribution halted in South Africa. That’s due to concerns about its efficacy in combating a variant of the virus prevalent in that country, though health officials in Britain still believe it can be a useful tool. 

The New York Times reported that, based on emergent evidence that the AstraZeneca vaccine is not sufficiently protecting clinical trial volunteers from mild or moderate illness caused by the more contagious virus variant first found in South Africa. The B.1.351 variant is also reportedly infecting people who contracted other versions of the coronavirus and are believed to have developed antibodies against those. 

That news is creating concerns about future mutations and the efficacy of vaccines that have been rolled out so far. However, the New York Times notes that the latest reports from South Africa might not be entirely conclusive. For one, “the number of cases evaluated as part of the studies … were low, making it difficult to pinpoint just how effective or not the vaccine might be against the variant.” 

The article also noted, “Because the clinical trial participants who were evaluated were relatively young and unlikely to become severely ill, it was impossible for the scientists to determine if the variant interfered with the AstraZeneca-Oxford vaccine’s ability to protect against severe COVID-19, hospitalizations, or deaths.”

Indeed, should the vaccine be deemed effective against more severe cases, that could result in inoculations resuming with the AstraZeneca vaccine. 

CNN characterized the news as “a big blow for the Oxford-AstraZeneca vaccine, which has been hailed for its low cost and easy storage as one of the world’s best hopes for defeating the virus.” 

The concern comes in part from the increasing global spread of the South Africa variant, now in 41 nations including the U.S., according to the World Health Organization. 

CNN reports that the issue is already being addressed. An AstraZeneca spokesperson stated that the company was working with Oxford University to adapt the vaccine against the B.1.351 variant, hoping that it will be ready by the fall of 2021. Several other COVID-19 manufacturers are at work on booster shots to protect against B.1.351. 

But as Al-Jazeera reported, British researchers behind the AstraZeneca vaccine still tout its usefulness despite the challenge of staying one step ahead of a mutating virus. “This study confirms that the pandemic coronavirus will find ways to continue to spread in vaccinated populations, as expected,” said Andrew Pollard, chief investigator on the Oxford vaccine trial. “But, taken with the promising results from other studies in South Africa using a similar viral vector, vaccines may continue to ease the toll on healthcare systems by preventing severe disease.”

Professor Shabir Madhi, lead investigator on the AstraZeneca trial in South Africa, said the vaccine’s similarity to the Johnson & Johnson vaccine, which reduced severe disease by 89%, suggested it would still prevent serious illness or death.

“There’s still some hope that the AstraZeneca vaccine might well perform as well as the Johnson & Johnson vaccine in a different age group demographic,” Madhi remarked. 

Sarah Gilbert, a University of Oxford professor of vaccinology quoted by Al-Jazeera, weighed in regarding the booster shot efforts. 

“This is the same issue that is faced by all of the vaccine developers,” she observed, “and we will continue to monitor the emergence of new variants that arise in readiness for a future strain change.” 

The Pfizer and Moderna vaccines, which have the highest efficacy against COVID-19 than any other vaccine, also have posted less successful results against the South Africa variant.

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Sources: New York Times, CNN, Al-Jazeera

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