A Simple Explanation

What follows is copied and pasted from a Canadian Press article I found on Yahoo.ca.  I have not changed one word.  The link for the whole article is here.

There are plenty of places to learn about the vaccines that are being rolled out to populations world wide, but this is the simplest, clearest explanation I have seen of just what each is and does.  

At the beginning of this pandemic I said quite clearly that this blog (or any non-expert blog, Facebook page, bathroom wall graffiti or anywhere that isn't the CDC or Health Canada) is NOT the place to be getting your Covid advice.  That still holds, but it seems to me that a little straight up, non-political, scientifically sound information never hurts, so:

VIRAL VECTORS

All of the approved COVID-19 vaccines train the body to recognize the spike protein that coats the outer surface of the coronavirus.

Johnson & Johnson and AstraZeneca use a harmless version of a cold virus as a vector to give our cells the instructions they need to make the coronavirus's spike protein.

 The immune system recognizes the protein and makes antibodies, which then allow us to fend off attack if exposed in the future.

Johnson & Johnson uses a human adenovirus, or a cold virus, to create its vaccine while AstraZeneca uses a chimpanzee version.

Johnson & Johnson's is the first single-dose vaccine approved in Canada. AstraZeneca, like Pfizer and Moderna, requires two doses.

Experts say it takes a couple weeks for the body to build up some level of immunity with any of the vaccines.

MESSENGER RNA VACCINES

Moderna and Pfizer use messenger RNA (mRNA), a novel technology that essentially teaches our cells how to produce the coronavirus's spike protein. That triggers an immune response if we become infected with the virus in the future.

All four of the vaccines basically work the same way, but there's one less component involved with the mRNA versions. Whereas the viral vectors use another virus to give our cells the info they need to make the spike protein, mRNA dumps the genetic code in directly, without using another virus as a vessel.

Pfizer and Moderna use synthetically-produced mRNA that's packaged in a fat coating. The mRNA is dumped into the cell when the vaccine is injected into the arm muscle and it then translated into protein to make the antibody.

The vaccines from Pfizer and Moderna were the first inoculations approved for humans to use mRNA, but the technology was being worked on for decades before it was adapted to vaccine creation.

Previous research had been done on creating mRNA vaccines against Zika and other viruses, and there were earlier efforts focused on cancer treatments.

Early pitfalls against the mRNA technology was that it was too unstable and fragile, with the mRNA disintegrating upon entering the body. That problem was solved by packaging it in the fat coating, giving it something to help bind onto cells easier.

 And there you have it.  If you have concerns or questions, I again recommend research at the CDC or Health Canada.  What you've just read is a simple explanation of some pretty amazing science and it never hurts to know more.

Stay safe, wear your mask, get vaccinated when your turn rolls around.  If we all work together, things might get back to normal before I'm too old to enjoy it...