Covid-19 Variants Causing Scientists To Rethink Vaccine Strategy

After the AstraZeneca vaccine showed a limited effect against the South African Covid-19 variant, scientists began strategizing on how to combat this next phase of the pandemic.

Embed from Getty Images

Top vaccine scientists throughout the world have made it known that current Covid-19 vaccine rollout programs need to be reexamined after variants of the virus are proving to be more resistant. This means that as of this moment, a proper herd immunity may not be possible due to these multiple variants appearing. The comments originally were in response to AstraZeneca’s acknowledgement that their vaccine would not protect people against mild to moderate Covid illness caused by the South African variant. 

A study involving more than 2,000 people in South Africa was performed after the Novavax and Janssen vaccines were trialled and found to have reduced protection against the variant. Pfizer/BioNtech, and Moderna have also said that their vaccines will likely be not as effective against the new variant; although no solid studies have been performed to prove that. 

All of the approved vaccines globally, however, have proven to protect against severe cases of Covid, as well as prevent hospitalization and death should a vaccinated individual be infected. Zweli Mkhize, South Africa’s health minister, recently spoke to the media about the decision to suspend the use of Oxford’s vaccine while scientists figure out the best way to combat these new strains.

“These findings recalibrate thinking about how to approach the pandemic virus and shift the focus from the goal of herd immunity against transmission to the protection of all at-risk individuals in the population against severe disease.”

UK vaccines minister, Nadhim Zahawi, ensured UK residents that the AstraZeneca/Oxford vaccine “appeared to work well against the Covid-19 variants currently dominant in the UK,” which is where a different strain of this virus initially appeared. “In terms of other variants, not in the UK, we need to be aware that even where a vaccine has reduced efficacy in preventing infection there may still be good efficacy against severe disease, hospitalization, and death.”

“Our studies confirm that the pandemic coronavirus will find ways to continue to spread in vaccinated populations, as expected, 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 health care systems by preventing severe disease,” said Professor Andrew Pollard, the chief investigator on the Oxford vaccine trial.

Sarah Gilbert is a professor of vaccinology at Oxford, who recently spoke about how even if the vaccines don’t bring “down the numbers of those infected with variant strains, they’ll still save lives, and while we may not be reducing the total number of cases, there’s still protection in that case against deaths, hospitalizations, and severe versions of the disease.” 

Embed from Getty Images

“To prevent people going into hospital with Covid would have a major effect. That’s really important for healthcare systems, even if we are having mild and asymptomatic infections.”

Embed from Getty Images

Ravi Gupta, a professor of clinical microbiology at the University of Cambridge, believes that “we probably need to switch to protecting the vulnerable, with the best vaccines we have which, although they don’t stop infection, they probably do stop you from dying. Because we have better access to vaccines, we can be more ambitious but different countries pursue different strategies, then travel resumes and it may be very hard to stop these variants.”

All vaccine developers are currently working on tweaking their vaccines in an attempt to increase their efficiencies against new variants that have mutations on the main spike protein that many of the vaccines target or work to replicate. Gilbert stated that  “we have a version with the South African spike sequence in the works. It looks very likely that we can have a new version ready to use in the autumn. This would open up the possibility of some people having a third jab later in the year.”

More than 100 cases of the South African Covid-19 strain have been found in the UK so far, and while attempts are currently being made to curb the spread with quarantining measures and house-to-house testing, effective vaccines really are the best solution. In order to reach a proper herd immunity against all variants of this virus we must ensure that all the vaccines are effective enough. 

Experts are claiming there is a chance we’ll all have to either get a third vaccine in the fall, or potentially receive booster shots annually, like with a flu shot, in order to maintain that immunity against the new strains especially. For now, it’s imperative that everyone at home does their part by listening to all proper health and safety procedures, and wait until it’s their turn to be vaccinated.