January 27, 2021
ByMike Lipscomb

In December 2020, two vaccines were granted emergency use authorization (EUA) by the Food and Drug Administration for prevention of COVID-19 in the United States. As these vaccines become widely available, we encourage all clinicians, hospital and health system leaders and other clinical professionals to share educational COVID-19 vaccine resources and insights about vaccine safety, how the vaccines work and the similarities and differences between the two.

mRNA Vaccines

Messenger RNA (mRNA) vaccines are a technology that have been studied for more than a decade but are still relatively new to the market. mRNA vaccines can be developed in a laboratory with readily available resources which allows for processes to be more streamlined and efficient, decreasing time spent in development versus traditional methods. While the development is quicker, this does not mean mRNA vaccines bypass safety testing. The vaccines undergo rigorous safety and effectiveness testing, following the same process as all other vaccines.

Instead of putting a weakened or inactive virus or bacteria into the body, mRNA vaccines inject a harmless protein (the mRNA) into the body. The mRNA stimulates the body’s cells to make a small piece of a protein called the spike protein – a protein found on the surface of the COVID-19 virus. The creation of the spike protein causes the body to trigger an immune response, just as it does for any foreign material introduced into the body. Part of this immune response produces antibodies which are essential in protection from the virus.

Two common misconceptions are: (1)the vaccine can give an individual COVID-19 and (2)it changes an individual’s DNA. The CDC reports both statements to be false. The two mRNA COVID-19 vaccines do not contain the live virus (they only contain a small part of the virus), meaning they cannot give someone COVID-19. The vaccines also do not change an individual’s DNA after receiving the injection since the mRNA never enters the nucleus of the cell, and mRNA cannot alter DNA. The mRNA remains active for several days to generate antibodies and other parts of the immune response, then breaks down and does not remain in the body.

CDC Reference

Additional Resource about mRNA Vaccines

Moderna & Pfizer-BioNTech Comparison

Both vaccines have been through rigorous safety testing which is important to reiterate. Both vaccines are reported to have high-efficacy rates, and both are considered extremely safe. Clinical trials show the Moderna vaccine was 94.1% effective in preventing COVID-19 in people who received both doses and no previous evidence of being infected. Clinical trials show a 95% efficacy for the Pfizer vaccine for prevention of COVID-19 in people without evidence of being infected previously. Once you receive a given vaccine, you are recommended to receive the same brand for the second dose. For example, if you receive the Moderna vaccine as the first dose, the second dose should also be the Moderna vaccine and administered within the recommended schedule. This recommendation is the same for the Pfizer-BioNTech vaccine. Additionally, side effects and adverse effects of both vaccines are followed very closely, and both the initial and follow up data all suggest both vaccines are extremely safe.

Take a look at the Moderna and Pfizer-BioNTech comparison below with facts from the CDC website.

As noted in the comparison above, there are very subtle differences between the two vaccines. These minor differences should not build a preference for receiving one vaccine versus another, unless there are other reasonings after reviewing the manufacturers information.

Additional CDC References: Moderna & Pfizer-BioNTech

Pfizer-BioNTech Manufacturer Information

Moderna Manufacturer Information

Herd Immunity Benefits

Vaccination of others in the community makes vaccination more efficacious to an individual, a concept called herd immunity. While the exact percentage of people who need to be vaccinated with the COVID-19 vaccine for herd immunity is not yet known, estimates are between 70-90%. Herd immunity makes virus spreading through a population more difficult as immunized individuals cannot contract and spread the virus. Herd immunity may also protect those who are not eligible for a vaccine, such as newborns. Although we are not sure if we can achieve full herd immunity, even rates below full immunity can be beneficial. As we focus on the different groups and furthering the amount of people vaccinated, we hope to see positive results of decreased numbers of infected people.

About Vaccines CDC Resource

New information about the COVID-19 vaccines is available daily. In today’s environment, it is imperative to stay abreast with COVID-19 data tracking, how the healthcare system is responding (nationally, statewide and locally) and any changes. There are a number of tools and resources available to healthcare providers. Take a look at several we’ve found most interesting below.