A Question For Science Chic

Pony Soldier wrote: Since we're doing Q&A with SC, I'd like to jump in with one. I am 99.9% sure this is BS, but can you take a look and give your take?

healthandmoneynews.wordpress.com/2020/12...emale-sterilization/

Thank you for asking PS, I'm now seeing this pop up on a few of my conservative friends' timelines and appreciate the opportunity to look into it and find out more. There are no stupid questions and it's not a waste of time to want to learn more. Ever.

So the contention by the former Pfizer employee (not "head of Pfizer," as the headline erroneously states - a red flag right off the bat) is that the vaccine is being raised against a protein on the SARS-CoV-2 virus that is similar to a protein, Syncytin-1, contained in placentas and may cause a secondary unintended auto-immune response attacking placentas and thereby causing infertility. Now, right off the bat, my first question was that if this hypothesis is true, then we should expect to see increased spontaneous abortions due to COVID-19 infections in the hundreds of thousands-millions of infected pregnant women in the world (~5% of women of reproductive age in the general population are pregnant at any given time) because the innate immune response against COVID-19 would also target Syncytin-1 in the placenta causing fetus loss. A cursory review of studies, such as this one, are not seeing increased abortions due to COVID-19, but I didn't spend a lot of time reading through many more references available. Abortions not increasing would indicate that if the innate immune response to SARS-CoV-2 infection doesn't cause spontaneous abortions, then neither should any human-created immunizations raised against the same protein.

There's quite a fascinating biology with placentas that must be kept in mind that makes this a lower concern (though not zero), not to mention the fact that this will obviously not be a concern at all for men or women who are no longer fertile or planning to have children. If long-term study of the vaccine therapy confirms that it is not a long-lived effect, then it will be similar to chemotherapy causing temporary infertility at worst.

Bottom line, the viral protein being targeted is similar but not close enough to Syncytin-1 to be a significant concern, and early evidence of the effects of COVID-19 infections don't cause increased abortions so it's most likely a non-issue; however, this is a novel vaccine and adverse event monitoring is definitely warranted.

Here's a blog that goes into better detail, if you're interested:

Are COVID-19 Vaccines Going To Cause Infertility?
Edward Nirenberg | December 3, 2020

The short version: Someone has claimed that the COVID-19 vaccines are going to cause infertility because of a shared amino acid sequence in the spike protein of SARS-CoV-2 and a placental protein, which will make the immune system attack both as it can’t tell the difference. The truth? This sequence is too short for the immune system to meaningfully confuse it with placental proteins. It’s sort of like saying that you are going to be confused with a criminal because you wear a commonly sold red bracelet that was also found on the criminal. It’s not realistic. If this were true, we would also expect COVID-19 to cause early pregnancy loss a significant amount of the time. The evidence available to us does not support that this is the case. There is no reasonable basis to believe that vaccines against COVID-19/SARS-CoV-2 will affect fertility.

The thing is, there is already excellent reason to doubt this is a reasonable claim, and that’s because of COVID-19. While COVID-19 seems to be a more severe disease in pregnancy, there is no evidence right now of an increase in early pregnancy losses, as might be expected if there were an aberrant immune response directed against placental antigens.

There's quite a few more references contained in here if you want to dive into this more:
Characteristics of Women of Reproductive Age with Laboratory-Confirmed SARS-CoV-2 Infection by Pregnancy Status - United States, January 22-June 7, 2020
MMWR Morb Mortal Wkly Rep. 2020 Jun 26;69(25):769-775. doi: 10.15585/mmwr.mm6925a1.

About the mRNA-based vaccine:
Want to Know More About mRNA Before Your COVID Jab?
A primer on the history, scope, and safety of mRNA vaccines and therapeutics
by Kristina Fiore, Director of Enterprise & Investigative Reporting, MedPage | December 3, 2020

For those who want more information on the history and science of mRNA vaccines and therapeutics before getting their jab, here's a primer.

How It Works

Biologically, messenger RNA is transcribed from DNA and travels into a cell's cytoplasm where it's translated by ribosomes into proteins.

For the Pfizer/BioNTech and Moderna vaccines, the synthesized mRNA is cloaked in a lipid nanoparticle in order to evade the immune system when it's injected. Once it's inside a cell, the ribosomes will get to work pumping out the spike protein of SARS-CoV-2.

The immune system then mounts a response to that protein, conferring immunity to the virus without ever having been infected by it.

Essentially, instead of pharma producing the proteins via an expensive and difficult process, mRNA enlists the body to do the work.

mRNA vaccines have been tested in humans before, for at least four infectious diseases: rabies, influenza, cytomegalovirus, and Zika.

Their chief safety concerns, which they said should be closely watched in future trials, were about local and systemic inflammation, as well as keeping tabs on the "expressed immunogen" and on any auto-reactive antibodies.

"There's no risk of incorporation into host chromosomes, and levels of mRNA and protein will decline and clear."