Kali Kniel, Professor of Microbial Food Safety, University of Delaware, kniel@udel.edu
It is late springtime, when the sun is shining, and the soil temperatures are rising. A variety of crops are being harvested, while others are being planted; yet as a society we are still struggling with COVID-19 in many ways. An important strategy to reduce disease and get back on track to “normal” life is through vaccination. Let’s get some facts straight regarding COVID-19 vaccine effectiveness and safety. This is our shot to stop the COVID-19 pandemic. Having access to three different vaccines is a remarkable act of science. But these new vaccines are actually built upon decades of scientific findings and research; hard work that farmers can truly appreciate. Scientists have been researching other coronaviruses that cause critical illness for decades before the emergence of the new coronavirus that is causing the COVID-19 pandemic. This previous research on other coronaviruses and vaccines is in part what allowed the rapid development of vaccines in 2020. Since the onset of the COVID-19 pandemic the world has witnessed remarkable mobilization of resources, skills, and dedication from vaccine researchers. This type of collaboration allowed us to have the highly the effective vaccines we have today.
Vaccines train our immune systems to react and protect us from viruses or bacteria that could cause disease. We are fortunate that the virus that causes COVID-19, has a spike protein located on the virus outer surface that is a perfect target for use in vaccine development. I am sure you have seen this spike protein in various images. This means that upon vaccination, our immune systems will respond by making appropriate immune cells that will have memory of this protein and fight those virus particles in the future. Development of this memory by our immune system typically takes a few weeks. Additionally, for some vaccines the first dose may not provide as much immunity as possible, so a second dose is required to build a more complete immunity. In a way, this is like hearing a story for the second time, I don’t know about you, but it helps me to remember something when I hear it again.
Medical and scientific experts from around the world have extensively reviewed the manufacturing procedures and effectiveness of all currently used COVID-19 vaccines. In the United States at this time, there are two vaccines that use mRNA to deliver the instructions for the spike protein, made by Pfizer and Moderna; and one vaccine, from Johnson & Johnson that uses another virus to deliver the instructions. The recent pause we experienced with the J&J vaccine provides evidence of the close regulation and review of this vaccination process. I feel extremely confident in the safety of the vaccines that we have available to use today.
The ways that these three vaccines are manufactured, offers multiple advantages in a pandemic-response because they are highly flexible, efficient in design and easier to manufacture in large amounts. The process to create the mRNA vaccines is built on previous experiences and as soon as the genetic sequence of the new coronavirus was determined in January 2020, scientists were at their benches strategizing how to use the spike protein to develop a vaccine. These vaccines contain simple instructions to make the coronavirus spike protein. This blueprint is either stored in a single piece of genetic material (mRNA) surrounded by tiny fat particles that allow it to enter our cells; or with the J&J vaccine, a virus that cannot cause disease carries these instructions. I realize that this may sound surprising, but these vaccines save lives, protect us from severe illness, and will allow us to get back to “normal”. The reported protection for both mRNA vaccines is generally greater than 90%, which is outstanding. I am looking forward to summer festivals and sporting events, and we can all celebrate these good times if we all do our part and get vaccinated. Next week, we will address other questions, like should my workers get vaccinated?