
Critical Care and Emergency Medicine doc in Chicagoland
The Pre-brief
A new variant of SARS-CoV-2 that was identified in September is rapidly becoming the dominant viral strain in southern England. This has raised concerns regarding the new strain’s potential increased transmissibility and possible resistance to medications and vaccines. To be clear, mutations are not unexpected and SARS-CoV-2 lineages generally go through 1-2 mutations a month.
Currently, The COG-UK, which examines viral genetic samples of ~10% of positive cases in England, is tracking 8 different strains of SARS-CoV-2. What is unique about this variant, called B.1.1.7, is that it has acquired 17 new mutations. Several of these mutations involve the infamous spike protein, which the virus uses to enter host cells. It is unclear if these mutations are directly responsible for the rapid increase in COVID-19 cases in southern England or just a coincidence in the setting of human behavior promoting viral spread. Preliminary analysis, however, suggests it is ~70% more transmissible between individuals than prior strains.
Could this potentially lead to the third British Invasion á la George III and George Harrison? Unknown. The B.1.1.7 SARS-CoV-2 variant has been seen in other European countries and a viral lineage with similar mutations has been found in South Africa. This particular strain has not been found in the U.S. thus far, but experts, including Dr. Fauci, suspect it’s already within the community. We likely haven’t detected it yet because our genetic sequencing capabilities are not as robust as other countries.
Is the vaccine now useless? No. More testing needs to be done on this new SARS-CoV-2 variant, but scientists are highly skeptical that the virus would develop immunity to the vaccine this rapidly. To develop any sort of meaningful resistance to the vaccines currently deployed would likely take years and many more mutations.
Highly recommend following @mugecevik on twitter for up-to date information on this topic. Dr. Çevik is a lecturer and researcher in Infectious Disease and Virology at the University of St. Andrews.
The Debrief
- Yes, the virus mutates…a lot. That’s expected.Â
- Yes, this particular lineage made a big mutant jump compared to prior variants.
- No, we don’t have enough solid information to know how infectious this strain is or if it is any more lethal than prior variants.
- No, it’s unlikely the vaccines will become obsolete this quickly.
- Yes, we need to collect more data to make any meaningful conclusions.
- Yes, everyone still needs to wear masks, practice social distancing, and get the vaccine when available to them.
Some more resources:
- https://virological.org/t/preliminary-genomic-characterisation-of-an-emergent-sars-cov-2-lineage-in-the-uk-defined-by-a-novel-set-of-spike-mutations/563
- https://www.biorxiv.org/content/10.1101/2020.05.04.077735v1.full
- https://www.ecdc.europa.eu/sites/default/files/documents/SARS-CoV-2-variant-multiple-spike-protein-mutations-United-Kingdom.pdf
- https://www.nytimes.com/2020/12/20/health/coronavirus-britain-variant.html
- https://www.washingtonpost.com/world/2020/12/23/us-leads-world-coronavirus-cases-ranks-43rd-sequencing-check-variants/
- https://apnews.com/article/new-coronavirus-strain-england-explainer-74ea2d47820b8dcac02f95ad9440f533