How the new strains of COVID-19 could affect vaccine strength

south africa strain covid
Photo via NIAID/Flickr (CC BY 2.0)
  • Viral mutations have not rendered vaccines ineffective
  • Vaccines may need to adapt to combat multiple strains of COVID-19
  • Moderna said its vaccine would work against the U.K, South Africa strains

The COVID-19 vaccine devastated the world, froze social functions indefinitely, and forced people into their homes for months on end. Just as viable vaccination options came into play, several separate instances of the SARS-CoV-2 mutating have been reported in the U.K., South Africa, Brazil, and the U.S. Now, people are left to wonder whether the South Africa strain and all the other variants will still be covered by the COVID-19 vaccines. 

The variant observed in the U.K. and U.S. showed adaptations to antibodies in convalescent plasma, meaning that it is a stronger version of the viral strain which has caused months of global struggle. The virus was shown to “avoid” antibodies in one subject, and there is evidence that the strain is evolving to spread faster. A CDC model shows that this strain, B.1.1.7., could become the most prevalent in the U.S. by March 2021. 

Soon after, another variant was reported in South Africa and then in Brazil. The South Africa strain, aka the 501Y.V2 variant, of the virus may affect how well vaccines work because the appearance of the virus has changed. The current function of mRNA vaccines is based on the shape of the spike protein in the coronavirus. This protein is what gets replicated in a host cell’s nucleus, allowing the virus to mount an assault on the human immune system, and the vaccine allows for a host body to train its immune response around this shape. 

With this part of the virus being different in appearance, those who have received the vaccine may not have an immune response strong enough to avoid getting sick. 

The Brazilian P1 variant, in particular, poses a curious case: It doesn’t produce an immune response. Dubbed an “immune escape,” the lack of a response increases the chances of reinfection, Science Magazine reports. 

The World Health Organization convened its COVID-19 Emergency Committee on Jan. 14 to discuss these mutations, calling for a global attempt to sequence and track these mutations. With the variants being new and vaccines slowly rolling out but finally picking up steam in the U.S., it is unclear whether their theorized resistance to vaccines will become an immediate problem or one that will appear later. 

Science Magazine reports that these variants have not yet shown to be resistant to vaccines, but that doesn’t rule out the possibility that they could further mutate. On Jan. 25, Moderna announced that its version of the vaccine was still effective against the U.K. and South Africa strains of the virus but that it was also testing a booster for the South African version.

Multivalent vaccines, like many other medical terms, may become common in the global lexicon if these strains persist alongside the original strain. Multivalent vaccines are intended to work for multiple variants of an illness. 

While the new strains may not prove immediately challenging to the effectiveness of vaccines, the rapid increase in cases will pose a strong issue to already overwhelmed healthcare systems, as surges are expected to push them past their already strained limits. 

Read more about the COVID-19 variants:

Sources: STAT News, BBC, Science Magazine, CDC, The New York Times, The Atlantic

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