Opinions of Tuesday, 29 December 2020

Columnist: Isaac Ampong

Will the Pfizer and Moderna Covid-19 vaccines still work in the midst of the newly mutated SARS-CoV-2 strain?

Pfizer and Moderna's vaccines arget specific version of the viral spike protein Pfizer and Moderna's vaccines arget specific version of the viral spike protein

Just at the time that two key Covid-19 vaccines, Pfizer and Moderna Covid-19 vaccines, have been approved and mass vaccinations have begun in many countries including the U.S.A. and the U.K., a newly mutated viral strain thought to be more transmissible called “SARS-CoV-2 VOC 202012/01”, or “B.1.1.7.” have also surfaced raising public concerns as to whether these vaccines will be effective against the coronavirus. This piece of article highlights what are already known as well as what we currently don’t know about the new strain of SARS-CoV-2, and the Pfizer and Moderna Covid-19 vaccines.

It should be noted that the new variant strain of SARS-CoV-2 contains a series of mutations and was first described in the United Kingdom (UK) with high prevalence in London and southeast England. The differences between the old and new virus include 23 mutations in the virus’s genetic code that have changed four viral proteins. It has been reported that 8 of these 23 mutations influence the spike protein. This makes it critical since the spike protein helps the virus to enter human cells, and becomes a key target of immune response, both in fighting off the virus during infection and in protecting the host (humans) from the disease following vaccination with the Pfizer and Moderna vaccines.

Currently, it is still unknown whether the changes to the spike protein helps the virus to enter human cells more easily, causing the virus to be transmitted from person to person more readily and whether the two authorized vaccines offer protection against this new strain. Moreover, as to whether these mutations may alter how well the host’s immune system fights the virus, potentially reducing the efficacy of the current vaccines that target several parts of the spike proteins are yet to be determined. Also, at this time, there is no evidence that this variant causes more severe illness or increased risk of death.

However, as it is known, Pfizer and Moderna were made to produce “polyclonal,” antibodies that target specific version of the viral spike protein. The version of the spike protein used by the vaccines was designed to match that of the old virus, not that of the new strain. Therefore one could argue that the vaccine-virus mismatch might make these vaccines become less effective for the new virus than the old virus for which the vaccines were originally made for. But, since the severity of the mismatch has not been determined, at this point it’s too difficult for scientists to conclude that these two authorized vaccines would be less effective. Again, the good news is that even in the case of virus-vaccine mismatch, the flu vaccine still offers some level of protection as it reduces the likelihood, and the severity, of disease. So with the Covid-19 vaccines made to produce antibodies that target several parts of the spike protein, it will require the virus to accumulate multiple mutations in the spike protein to evade immunity induced by vaccines or by natural infection. Therefore, I still support that people should allay their fears and get vaccinated with the Pfizer and Moderna vaccines when the opportunity is presented. This way we can get the virus under control to prevent it from evolving further, particularly, now that the new strain has not spread substantially across the world. In the meantime, until many people are vaccinated, everyone needs to keep up with the 3Ws-Wear mask, Wait 6-feet apart and Wash their hands with soap or use hand sanitizer.