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  • Scientists Worry COVID-19 Vaccines May Not Work against South African Variant

  • Three vaccines with emergency use authorization and two COVID-19 variants are facing off in the first quarter of 2021

  • Between the UK and South African variants, experts are worried if the vaccines will work against the latter

  • The data from genomic sequencing suggests mutations in the South African variant may resist vaccines

  • Lawrence Young, a virologist at Warwick University, said: "The accumulation of more spike mutations in the South African variant are more of a concern and could lead to some escape from immune protection"

  • Scientists across the globe, including BioNTech's Ugur Sahin and Oxford University's John Bell, are testing if COVID-19 vaccines can overcome the mutations

  • The testing will show them too what needs to be done in case the vaccines are less effective

  • Doing so may allow them to change parts of the vaccines in just weeks, instead of starting from scratch

  • But why experts are more worried about the South African variant than the UK strain?

  • According to the US CDC, the South African B.1.351 variant emerged independently of the UK strain B.1.1.7

  • Both exhibited high transmissibility rates in reported cases

  • However, B.1.351 has a few more surprises

  • Simon Clarke at the University of Reading confirmed that the South African variant has extra mutations, compared to the UK variant

  • The excess alterations are linked to the spike protein of the coronavirus

  • Not only do the mutations increase the chance of infecting human cells, but also raise the ability to dodge the immune system

  • Because the vaccines elicit an antibody response, any changes in the antigen may impair antibodies

  • If the coronavirus has several mutations in its antigen, antibodies from vaccines may not bind correctly, resulting in reduced effectiveness

  • Public Health England said there's no evidence yet to support that COVID-19 vaccines wouldn't work against the variants, Reuters reported

  • Aside from high transmissibility rates, both variants are correlated to higher viral loads

  • When a person contracts either strain, their body would likely have a greater concentration of virus particles, which means, better odds of transmitting the variant to others

  • So, scientists are investigating two things

  • Will the vaccines work on the UK variant?

  • If yes, will these vaccines protect people from the South African variant?

  • Globally, 60 vaccines are in clinical trials, including the ones from Pfizer/BioNTech, AstraZeneca/Oxford, Moderna, Gamaleya Institute, and Sinopharm

Scientists Worry COVID-19 Vaccines May Not Work against South African Variant


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科學家擔心COVID-19疫苗可能對南非變種無效 (Scientists Worry COVID-19 Vaccines May Not Work against South African Variant)

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    Amy.Lin 發佈於 2021 年 01 月 14 日