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1) THREAD - A summary of NERVTAG’s (the U.K. virus committee who advise the government) opinions on the ‘new U.K. strain’ of SARS-CoV-2.
2) We’ve previously discussed our opinions on this matter. We believe that there is currently not enough evidence to call this new virus variant a new strain.
However, our opinions may change as more reports are published. https://twitter.com/SimplyBiochem/status/1338843976108011524
However, our opinions may change as more reports are published. https://twitter.com/SimplyBiochem/status/1338843976108011524
3) In our thread we mentioned that this variant contains the substitution mutation N501Y in the spike protein. It also contains a deletion in the RNA code. In combo, this may change its structure, but none as of yet have been shown to have a definitive impact on viral physiology.
4) However NERVTAG predicts that this variant behaves differently. They say they have ‘moderate confidence’ that this virus is more transmissible.
Let’s discuss.
Let’s discuss.
5) The way NERVTAG came to this conclusion was not through study of the spike protein but through a mixture of assessing:
a. Growth rate compared to others
b. R value correlation w/variant
c. PCR threshold value for positive C-19 test (Ct value)
d. Viral load measured by PCR
a. Growth rate compared to others
b. R value correlation w/variant
c. PCR threshold value for positive C-19 test (Ct value)
d. Viral load measured by PCR
a) Growth rate. (1/4)
Prevalence suggests it grew at a rate 71% faster than other variants. It grew during lockdown and when other variants were thought to be in high prevalence, suggesting higher transmission.
However.. this phenomenon can happen without selective advantage.
Prevalence suggests it grew at a rate 71% faster than other variants. It grew during lockdown and when other variants were thought to be in high prevalence, suggesting higher transmission.
However.. this phenomenon can happen without selective advantage.
This is called the Founders Effect. (2/4)
This would happen if a few carriers of the new variant suddenly migrated into an area where there were hardly any other variants.
It would grow exponentially as it has no competition, eventually leading to its prevalence in that area.
This would happen if a few carriers of the new variant suddenly migrated into an area where there were hardly any other variants.
It would grow exponentially as it has no competition, eventually leading to its prevalence in that area.
This variant grew in lockdown right? (3/4)
During lockdown, social mixing is limited, causing other variants to reach ‘near extinction’ levels, allowing for growth of this particular variant in the space that they had vacated.
It took over because everyone else was gone.
During lockdown, social mixing is limited, causing other variants to reach ‘near extinction’ levels, allowing for growth of this particular variant in the space that they had vacated.
It took over because everyone else was gone.
Therefore the reason for the increased growth of this variant could be lockdown. (4/4)
Having said this, selective advantage cannot be ruled out.
Having said this, selective advantage cannot be ruled out.
b. R value correlation w/variant
The R value is a measure of infectiousness. A higher R value correlated with this particular variant.
But, this new variant arose just before winter. Below we explain how cold weather increases C-19 susceptibility. https://twitter.com/SimplyBiochem/status/1339197850509586438
The R value is a measure of infectiousness. A higher R value correlated with this particular variant.
But, this new variant arose just before winter. Below we explain how cold weather increases C-19 susceptibility. https://twitter.com/SimplyBiochem/status/1339197850509586438
c. PCR threshold value (1/2)
PCR analysis show that values measured for positive tests (ct values), were suggested to be 2 points below average than other variants, meaning in some cases they may go undetected.
However, Ct values can vary dependent on when a patient is tested.
PCR analysis show that values measured for positive tests (ct values), were suggested to be 2 points below average than other variants, meaning in some cases they may go undetected.
However, Ct values can vary dependent on when a patient is tested.
This may contribute to why it’s spreading so quickly, false negative tests. (2/2)
d. Viral load
The report says there is an increase in viral load in this variant, which means an infected person carries more virus particles, so is more contagious. But there is no indication as to how much.
The report says there is an increase in viral load in this variant, which means an infected person carries more virus particles, so is more contagious. But there is no indication as to how much.
6. So, is this variant a new strain? Maybe?
Does it impact transmission? Maybe?
Do we have enough publicly available data to make any conclusions? Not yet.
We’ll keep ya posted!
Does it impact transmission? Maybe?
Do we have enough publicly available data to make any conclusions? Not yet.
We’ll keep ya posted!
7) For anyone who wants to see the NERVTAG report! 
https://khub.net/documents/135939561/338928724/SARS-CoV-2+variant+under+investigation%2C+meeting+minutes.pdf/962e866b-161f-2fd5-1030-32b6ab467896?t=1608470511452
https://khub.net/documents/135939561/338928724/SARS-CoV-2+variant+under+investigation%2C+meeting+minutes.pdf/962e866b-161f-2fd5-1030-32b6ab467896?t=1608470511452
8) Thoughts on the thread!
