Episode 1: Vaccine Safety 1: mRNA COVID Vaccines Explained

This episode was originally published in 2021 and was updated in March 2026 in two ways: safety (overall plus in pregnancy and kids) and immunity duration sections reflect five years of real-world data, and systems-level analytical segments have been added on why the most common mRNA conspiracy theories are biologically impossible, how the system failed us, and how to do better going forward. Updated text is in green in the corresponding blog post.

This is the original episode published in 2021, rebranded for Infectious Dose. Heather provides an in-depth discussion on the COVID-19 mRNA vaccines authorized for emergency use in the US. She covers:
·        What is mRNA
·        How mRNA vaccines work
·        How we know they are safe
·        Why they cannot change your DNA
·        How long might immunity last
·        Why those who’ve recovered from COVID-19 should get vaccinated
·        Comparison between the Pfizer and Moderna mRNA vaccines and more.

All citations are in the blog post at infectiousdose.com