COVID-19 Vaccine Facts

Updated 03/09/2021 8:38:21 AM


Q: What’s the difference between Moderna, Pfizer and Johnson & Johnson vaccines?

A: Moderna and Pfizer are mRNA vaccines. Johnson & Johnson is an adenovirus vector vaccine.

Q: Okay, but what does that mean?

Moderna and Pfizer are both mRNA vaccines. Traditional vaccines include weakened or inactive virus cells, but mRNA vaccines teach the body how to make the spikes that infect cells, but not the virus itself. The body is then able to learn to recognize and destroy Covid-19 spikes without ever having the virus. mRNA vaccines do not contain weakened or inactive Covid-19 cells, so they cannot give you Covid-19. They do not contain latex, eggs, or preservatives, which some people are allergic to.




Johnson & Johnson is a newly-approved adenovirus vector vaccine. This means that doctors have modified a harmless regular virus (in this case, the common cold) to be able to produce the protein spikes of Covid-19 cells. Just like the other vaccines, this means the body is able to learn to recognize and destroy Covid-19 spikes without ever having the virus. It does not keep you from contracting Covid-19 altogether, but does often prevent the case from becoming critical and life-threatening. 

Side effects can include pain, swelling and redness at the injection site and chills, fatigue and headache.




Johnson & Johnson

Ages 18 and Up

Ages 16 and Up

Ages 18 and Up

2 shots, 28 days apart

2 shots, 21 days apart

1 shot

Requires regular refrigeration

Requires specialized cold storage

Requires regular refrigeration

94% effective

95% effective

66-85% effective*

*preventing moderate cases (66%) and critical cases (85%) within 28 days of vaccination.



Please remember: vaccines keep you from getting sick, but that doesn’t mean you can’t still pass germs on to others. Even after vaccination, continue to wear a mask, wash your hands, and social distance to protect others, per CDC guidelines.



Centers for Disease Control and Prevention. (2021, February 25). Frequently Asked Questions about COVID-19 Vaccination. Centers for Disease Control and Prevention.

Centers for Disease Control and Prevention. (2021, January 1). Information about the Moderna COVID-19 Vaccine. Centers for Disease Control and Prevention.

Centers for Disease Control and Prevention. (2021, January 1). Information about the Pfizer-BioNTech COVID-19 Vaccine. Centers for Disease Control and Prevention.

Office of the Commissioner. (2021, February 27). FDA issues emergency use authorization for third Covid-19 vaccine.

Simply Explained. (2020, December 30). How mRNA vaccines work–simply explained.

U.S. Department of Health and Human Services. (2020, October 6). COVID-19 vaccine update: How vaccines are developed.


Evaluating Information Sources

Anybody can say anything they want on the internet–but that doesn’t make it true. There’s more information out there than ever before, which means two things: it’s easier than ever to find and access information, and not all of that information is reliable. So how do you know what information is right? Here’s an acronym that might help you remember: is it a TRAAP?

  • Timeliness. Is the information current? Up to date? We learn new things every day; does the website or article reflect that information or was it published before newer information became available?

  • Relevance. Is the information directly related to what you need to know? Does it answer your question specifically? 

  • Authority. What makes the author of the information an expert? For example, would you trust someone who’d never had any training or experience to build a house? Look for credentials–that is, what it is that makes them an authority on the topic.

  • Accuracy. How does the author prove that the information is reliable? Did they do their research? Cite their sources? Are they making claims that are supported by evidence? 

  • Purpose. What is the purpose of the information? Is it to inform, or share information, or is it to convince you of something? Does the author have anything to gain or lose by changing your mind about something? Would you trust a company that sold theme park tickets if they said that buying theme park tickets increased happiness by 95%? They have something to gain by making you believe something. Always look into why a piece of information was created and whether or not there is anything to back up their claims.