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.
4/ Second, in the case of RNA COVID-19 vaccines, the RNA message is for 1 single coronavirus protein. It takes 25 different coronavirus proteins to make a coronavirus, so there is no worry about the RNA making a virus.
5/ Third, over 70,000 doses of these COVID-19 RNA vaccines have been given to people now, and the independent safety boards (not controlled by the companies) have reported no serious concerns. That’s a lot of safety data!
6/ Now, it will certainly be good to see the full safety data when the clinical trial results become public, but it looks good.
7/ Lastly, regarding these vaccines and vaccines in general, “safe" does not mean the same thing as “did not hurt at all” or “no fever” for a little while. The immune system tends to only remember things that hurt somewhat. Not unlike going to the gym and getting exercise
8/ and really sore muscles; a bit of pain can be a positive sign that good things are happening. Sometimes you have to earn your immunity, just like you have to earn those biceps you wanted so bad. 😀
9/ An immunization is probably going to hurt some, and that’s generally a good sign. You are earning your immunity.
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1/ Here's my review on adaptive immunity to COVID-19 and SARS-CoV-2. I hope you find it useful. It was a lot of work. Thanks to Prof Alex Sette @SetteLab and others for direct contributions and broader input over the year! cell.com/cell/fulltext/…@CellCellPress
2/ And thanks to all of the amazing scientists and labs around the world that have done so much work making incredible progress on these challenging COVID-19 immunology topics in the past year!
3/ FYI, here's the right version of Figure 1. It should be updated in the next version posted online.
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. biorxiv.org/content/10.110…
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.
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). medrxiv.org/content/10.110…
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.
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)
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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. doi.org/10.1101/2020.1…
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.