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The six strains of SARS-CoV-2:
"The SARS-CoV-2 coronavirus is presumably already optimized to affect human beings, and this explains its low evolutionary change," explains Federico Giorgi, a researcher at Unibo and coordinator of the study. "This means that the treatments we are developing, including a vaccine, might be effective against all the virus strains."
Currently, there are six strains of coronavirus. The original one is the L strain, that appeared in Wuhan in December 2019. Its first mutation—the S strain—appeared at the beginning of 2020, while, since mid-January 2020, we have had strains V and G. To date strain G is the most widespread: it mutated into strains GR and GH at the end of February 2020.
Globally, strains G, GH and GR are constantly increasing. Strain S can be found in some restricted areas in the U.S. and Spain. The L and V strains are gradually disappearing.
Journal Reference:
Mercatelli, Daniele, Giorgi, Federico M.. Geographic and Genomic Distribution of SARS-CoV-2 Mutations, Frontiers in Microbiology (DOI: 10.3389/fmicb.2020.01800)
(Score: 5, Interesting) by Opportunist on Wednesday August 05 2020, @12:06AM (4 children)
Covid is a +ssRNA virus. They are well known to mutate heavily and quickly. This makes developing vaccines and cures against them very tricky. Developing a vaccine takes almost a year from inception to delivery, and that's already a pretty rushed job with very little time for testing. This is, by the way, one of the key reasons why there is still nothing we can really do against the common cold, which is also a +ssRNA virus. By the time we would have a vaccine against it, it has mutated enough to make the vaccine ineffective.
It's been theorized that Covid, while being a +ssRNA virus, has some "error correction" code in its genome, which would actually be a good thing for us since that means its mutation rate would be slower than what we see in other ssRNA viruses.
The key question is now whether those 6 strains are close enough still that a vaccine developed against the original strain L would be effective against the currently widespread strain GH.
(Score: 1, Interesting) by Anonymous Coward on Wednesday August 05 2020, @01:46AM (2 children)
From what I've seen in the phylogenetic analysis, it still appears close enough to get one vaccine for all of them. But even a partial vaccine targeting the right strains can make a monumental difference.
(Score: 0) by Anonymous Coward on Wednesday August 05 2020, @08:33AM (1 child)
But that's what the GP was getting at: it'll only make a monumental difference if the longevity of those strains is significantly longer than the development time of the vaccine. If the vaccine turnaround time from isolation to rollout is one year, and the virus mutates on average once a year, the vaccine is largely useless by the time it's ready: the targeted strain is already on its way out, and different strains might be spreading in its place.
(Score: 1, Insightful) by Anonymous Coward on Wednesday August 05 2020, @09:47AM
That's not how strains or mutations work. The proteins control whether the vaccine will be effective enough. Not every genetic mutation leads to phenotype changes or different proteins, not every protein change nullifies immune response, and not every strain has a different set of proteins. And we don't have to guess at this either. People have done the analysis of mutation rate and strains and all that. Right now, it appears that one vaccine can hit the entire SARS-CoV-2 species because the strains, while different, still aren't different enough because it is so young. Sure there are probably tens of thousands of substrains out there but they appear to be relatively conserved when you do the analysis.
What I really suspect has happened is she has looked at the much older Coronaviruses and how they don't have a vaccine and then mistakenly generalized to anything that falls under that entire family classification. Despite the fact that SARS-CoV-2 has important differences from others in the family that affect the ability to make a vaccine at all and different incentives and history in research that affects the creation speed, efficacy, and effectiveness of a vaccine candidate. SARS-CoV-2 is not the flu, it is not HIV, or Ebola, MERS, or even hCoV-229E, and generalizing from them to it is an easy way to come to wrong conclusions.
(Score: 1, Informative) by Anonymous Coward on Wednesday August 05 2020, @12:18PM
https://en.wikipedia.org/wiki/Common_cold#Viruses [wikipedia.org]
So not sure about that single virus you talk about when in fact there are HUNDREDS of viruses that are the "common cold".
Viruses don't mutate for no reason. They mutate when there are problems with their duplication. Some viruses don't mutate at all, even when there is a vaccine against them, like the "perfect" measles virus.
https://en.wikipedia.org/wiki/Positive-sense_single-stranded_RNA_virus [wikipedia.org]
Dengue is on the list there and it has a vaccine. So I'm not sure about that vaccine talk. Sounds to me like an arm-chair virologist (like me). Not every virus mutates just because it's a +ssRNA virus.