1/ One pre-print on B117 viral loads (i.e., B.1.1.7 SARS-CoV-2 ) found substantially higher viral loads (median 10-100 times). Another UK study found 3 times higher viral loads in people with B117 (Bonsall/Golubchik study).

4/ I look forward to seeing more definitive data on B117 viral loads. But, for now, as of today, I am operating under the assumption that the B117 strain is 3-times more abundant in the upper respiratory tract, and that may be a primary source of greater B117 transmission.
5/ With those assumptions, plus the as-expected result that Y501 mutation does not negatively affect neutralizing antibodies in COVID-19 cases or vaccines (Pfizer), I expect no significant impact of the B117 strain on vaccine efficacy for preventing COVID-19 disease.
6/ Thanks to @Mugecevik for pointing this important report out to me on viral loads!

7/ Again, with those assumptions, plus as-expected results that Y501 mutation does not negatively affect neutralizing antibodies in COVID-19 cases or vaccines (Pfizer), as of today, I expect no significant impact of B117 strain on vaccine efficacy for preventing COVID-19 disease.

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More from @profshanecrotty

9 Jan
1/ “I think this [study] is really important because there is a lot of fear and uncertainty at the moment about this specific question.”

“[the results are] not surprising, but it’s been really important to see some data.” 

2/ Definitely good news to see these data on the Pfizer vaccine working against the 501 variant. If anything, the vaccine works better against this variant.
3/ It isn't the end of the story, because the UK / SA variants have mutations in addition to 501, but these vaccine data are an important piece of the puzzle. As noted in the article, more is expected from labs in the coming weeks, but these results are expected & encouraging.
Read 4 tweets
6 Jan
1.  Our COVID-19 paper on Immunological memory to SARS-CoV-2 assessed for up to 8 months after infection is out today in @ScienceMagazine !
@ljiresearch @SetteLab @Dani6020
2. The immune system can remember viruses. And there are multiple different parts of the immune system that can remember a virus in different ways, so the immune system can fight the virus in multiple ways.
3. Our data shows that the body’s immune system remembers novel coronavirus for at least 8 months after COVID-19, and multiple different branches of the immune system remember the virus.
Read 8 tweets
31 Dec 20
1.  I am convinced that the new "UK variant" of SARS-CoV-2 (B.1.1.7) is a big problem. I look forward to seeing more epidemiology by more labs (not my area), but the overall picture plus these new viral load data now have me convinced. (my PhD was RNA virology)
2.  An analysis of 641 COVID-19 cases found "S-negative" (B.1.1.7 inferred) cases had 10 to 100-times higher nasal viral loads than 'regular' COVID-19. Virologically, that is a massive difference. It could easily explain higher transmissibility.
3. The authors of that work are appropriately cautious in their interpretations (e.g. they didn't directly sequence confirm B.1.1.7 cases), and it will be very valuable to see similar studies from other sites. But, I find the data compelling.
Read 7 tweets
17 Dec 20
A bit more in depth look at the Moderna FDA data.

1. 94% effective at preventing COVID-19

That matches the earlier data and public statements
2. Prevents severe COVID-19

Zero cases in the vaccinated group. 30 severe cases of COVID-19 in the placebo group.
3. Worked the same in older adults and other subgroups

That matches the earlier data and public statements.
Read 6 tweets
29 Nov 20
Got lots of interest in my RNA vaccine explainer yesterday. The most common follow up questions generally fell into two categories, well stated in the tweet below. I will answer both. 1/5

First, to paraphrase: “Isn’t it strange for the immune system to deal with a viral protein from RNA in host cells?” Actually, the human immune system has spent millions of years evolving to recognize viruses this way. (Really, vertebrates have spent 500 million years doing this!)
Viruses regularly express their proteins on infected human cells, and the immune system specifically recognizes those foreign viral molecules. Indeed, many viruses are RNA viruses (they use RNA as their genetic material!), so the immune system is specifically good at this job.
Read 5 tweets
27 Nov 20
1/ Are RNA vaccines safe? I have gotten this question a lot lately, and it is a good question.
2/ First: RNA is messages. At any moment a human cell has 5000+ different RNA messages, and they are all temporary messages, like post-it notes that get torn up by the cells within minutes or hours after being read.
3/ Or, actually, RNA is like snapchat messages that expire. RNA vaccines do NOT become a permanent part of your body. They are temporary messages instructing cells to make one viral protein temporarily.
Read 9 tweets

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