Mutant strain of coronavirus that may make it more infectious now ‘dominant’
Scientists have discovered a coronavirus mutation that is of ‘urgent concern’ because it makes the virus more contagious and has already become dominant in the places it’s reached – including part of the US.
Researchers at Los Alamos National Laboratory in New Mexico say that the mutant strain started spreading in early February in Europe.
It has since made its way to the US, where it became the most common – and aggressive – strain on the East Coast by March, and the scientists say its now the world-dominating strain.
In their report, which hasn’t been peer-reviewed but was posted to BioRxiv, the researchers warn that the vaccines currently in development across the US may not be effective against this mutant strain and urge that their discovery needs to be considered in further work on coronavirus treatments and shots.
A graphic from Los Alamos National Laboratory shows how the mutated spike protein, D614G became the dominant strain in Europe (red) and, to a lesser extent, North America (blue)
Generally speaking, coronavirus is relatively stable for a virus, meaning it’s not mutating at particularly high rates or speeds.
But that’s not to say it isn’t mutating at all, or that it’s limited mutations might have disastrous effects.
Los Alamos researchers developed a method to track the mutations that fuel the coronavirus’s mutation in ‘real time.’
Their analysis pipeline downloads all the viral genome sequences uploaded to the largest international database (the Global Initiative for Sharing All Influenza Data, or GISAID) daily and interprets how and where the virus is changing.
As they followed its progression, the team discovered 14 mutations.
Some were likely isolated to communities and popped up in their tracking as byproduct of the way the virus’s genome was being sampled.
The two strains that seemed to combine, G614 (blue) and D614 (orange) ramped up in late March across the globe, with G614 becoming particularly dominant
But others represent larger, more worrisome patterns, wrote the collaborating scientists from Los Alamos, Duke University and Sheffield University in the UK.
One in particular was cause for an ‘early warning.’
A mutation has occurred in the all-important spike protein – a part of the virus that juts out from its surface, earning it a name that means crown, and allowing it to infiltrate human cells.
The researchers dubbed the mutated protein Spike D614G.
It’s not clear if the mutated spike first emerge in China or Europe, but it certainly gathered its momentum in Europe, and then swept the globe.
When the scientists first reported Spike D614G in March, it had only appeared seven times in the sequences uploaded to GISAID (which lag about two weeks behind real time).
‘However, an early April sampling of the data from GISAID showed that G614’s frequency was increasing at an alarming pace throughout March, and it was clearly showing an ever-broadening geographic spread,’ the researchers wrote in their report published online on April 30.
It would seem that at some point, the G614 mutation and another, D614 mutation, merged to become the D614G mutation.
Together they’ve become dominant, and more infectious through several modes.
The spike protein is more infective, can more easily bind to receptors on human lung cells, become more active, and may even be more able to dodge the antibodies the human body develops to the virus.
‘Given Spike’s vital importance both in terms of viral infectivity and as an antibody target, we felt an urgent need for an “early warning” pipeline to evaluate Spike pandemic evolution,’ the study authors wrote.
‘If the pandemic fails to wane, this could exacerbate the potential for antigenic drift and the accumulation of immunologically relevant mutations in the population during the year or more it will take to deliver the first vaccine.
‘Such a scenario is plausible, and by attending to this risk now, we may be able avert missing important evolutionary transitions in the virus that if ignored could ultimately limit the effectiveness of the first vaccines to clinical use.’
The revelation of this mutation could put a wrench in the many clinical trials – including those from Moderna, Inovio, and Pfizer – that have recently kicked off i the US.
Source: Daily Mail | Health News
