COVID-19 Vaccine Myth Busters

By Janet Mulroy, DNP, ACNP, CCRN, CCNS Feb 22, 2021

Added to Collection

There’s a lot of information floating around about the COVID-19 vaccines.

There’s a lot of information floating around about the COVID-19 vaccines. I’m writing this blog to help you weed through some of the myths and provide you with the latest facts.

MYTH: COVID-19 vaccines were developed with fetal tissue.

FACT: The Moderna and Pfizer vaccines did not use fetal tissue during development or testing. In the 1960s, many vaccines did use fetal tissue during development and testing, but this process was not used for the currently approved mRNA vaccines.

MYTH: The vaccines are not safe, because they were developed very quickly and were not adequately studied. People were not followed long enough to know the risk for adverse effects.

FACT 1: Let’s talk about the speed first. Scientists began working on a vaccine for SARS-CoV-1 about 10 years ago when there was a SARS outbreak in Asia. The SARS-CoV-1 technology was rapidly adapted to SARS-CoV-2, and this was very helpful in creating a new vaccine so quickly.

Second: Funding for research, testing and clinical trials was quickly provided through our government. There was no time wasted in trying to secure funding so the scientists could do their work. This initiative is called Operation Warp Speed (OWS). OWS is a partnership between the Department of Health and Human Services, the Department of Defense, other federal agencies and private firms, whose purpose is to collaborate to accelerate the development, manufacturing and distribution of COVID-19 vaccines, therapeutics and diagnostics. This level of cooperation is making history; never before have we had such collaboration between federal agencies and private businesses.

FACT 2: Let’s discuss the adequacy of the clinical trials. The vaccine clinical trials follow the same strict guidelines as any other vaccine development outlined by U.S. federal agencies. A committee reviews every step of the process and all of the raw data. This committee consists of infectious disease scientists and physicians representing our best and brightest. Emergency use authorizations (EUAs) are granted by this group. It’s important to note that just because the vaccine received EUA, it doesn’t mean the vaccine trials stopped. The pharmaceutical companies are continuing to monitor the trial participants. There are over 60,000 volunteers in the clinical trials, and the data collected was overwhelmingly in support of moving forward with these vaccines. They are also monitoring reports from vaccination centers all over the United States.

For a brief explanation of EUA, please view the FDA’s YouTube presentation below. In addition, this link offers a side-by-side comparison of the Pfizer-BioNTech and Moderna vaccines.

MYTH: The COVID-19 mRNA vaccine will alter DNA.

FACT: The mRNA vaccine is a messenger RNA, and it does not alter DNA or interact with DNA in the cells. The mRNA strand never enters the cell’s nucleus or affects genetic material. It provides instructions to the cell to create a version of the spike protein unique to SARS-CoV-2 that stays on the surface of the cell. The newly made spike protein triggers the body to manufacture antibodies, which is the desired response, and the mRNA is later broken down by the body. Since only part of the protein is made, the mRNA vaccine does not cause any harm to the DNA of the person who was vaccinated.

Researchers have been working with mRNA vaccines for decades. Interest in these vaccines has grown, because they can be developed in a laboratory using readily available materials. This process also produces vaccines faster than traditional methods. mRNA vaccines were previously studied for SARS-CoV-1, MERS, flu, Zika, rabies and cytomegalovirus (CMV). Beyond vaccines, cancer research has used mRNA to trigger the immune system to target specific cancer cells. As soon as the viral genome was known, scientists began designing mRNA instructions for the unique spike protein so the mRNA vaccine could be produced.

MYTH: The COVID-19 vaccines have no adverse effects.

FACT: All vaccines have the potential for adverse effects. The purpose of the vaccine is to trigger a response in the immune system that produces antibodies. The immune response can mimic a mild form of the flu. Mild illness is described as fatigue, muscle aches, headaches and low-grade fever. These can be considered a good response to the vaccine, because it means the body is making antibodies. High fever and shortness of breath are not normal responses and usually indicate something else is going on. These symptoms should be evaluated by a healthcare provider.

MYTH: People who receive a COVID-19 vaccine under the EUA are not being monitored for adverse effects.

FACT: Moderna and Pfizer are participating in the CDC v-safe monitoring program to monitor people who receive a COVID-19 vaccine outside of the original studies. Each person who receives a vaccine is encouraged to sign up online for the CDC v-safe program. Because I enrolled in v-safe, I receive text messages from the CDC with a link to open a brief questionnaire. It asks me about adverse effects and to rate each adverse effect as mild, moderate or severe. If you report a moderate or severe response through v-safe, you will be contacted by the CDC for a follow-up.

MYTH: I already had COVID-19 so I don’t need the vaccine.

FACT: Those who have had COVID-19 have natural immunity. There have been some studies to suggest this immunity lasts from three to eight months, but it varies from person to person. Reinfection has occurred. The new variants of the virus may be less susceptible to natural immunity. We don’t know how long the vaccine immunity will last. People who participated in the early COVID-19 vaccine trials are being followed to measure levels of antibody response. This situation will require us to maintain high levels of caution with universal masking, hand hygiene and social distancing for some time. It will also require booster shots at some point. The plan is still to be determined. People who have already had COVID-19 infections are encouraged to get the vaccine to extend their levels of immunity. It’s important to remember that getting the vaccine helps lead to herd immunity, which is necessary to decrease the number of critically ill and dying patients.

MYTH: I need just one shot.

FACT: The mRNA trials that include the two currently with EUA approval indicate one shot will provide approximately 60%-65% protection, whereas a second shot provides 92%-95% protection. It is important to achieve levels of protection over 70% to slow the rate of illness and death.

The second Pfizer vaccine shot should be done at day 21 (three weeks). The second Moderna vaccine should be done at 28 days (four weeks). You should stay with the same product and get the same second vaccine as your first.

MYTH: There are no special considerations for people with allergies in regard to COVID-19 vaccination.

FACT: Those who have a history of allergic reactions to the ingredients in the currently available vaccines should not receive those vaccines. In addition, if you have an allergic reaction to the first dose of the vaccine, you should not get a second one. Individuals with other allergies may be able to undergo vaccination. The CDC encourages those with allergies to contact their primary care provider to review the risks and benefits of vaccination prior to scheduling a shot at a vaccine administration center. Review CDC guidance for those with allergies at

All vaccine administration centers must follow specific guidelines and preparations for setup and ongoing monitoring of preparation and safety.

MYTH: Once I get a vaccine, I don’t need to wear a mask.

FACT: You still need to wear a mask. What we know for sure, based on the clinical trial data, is that the vaccine will reduce your chances of becoming seriously ill if you are exposed. We don’t yet know if the vaccine will prevent you from being a carrier to other people. It is possible that even after vaccination, you are able to spread viral particles to others. Therefore, you should continue to follow the guidelines on social distancing, universal masking and hand hygiene until more data is available.

MYTH: The COVID-19 vaccine can cause infertility.

FACT: There are inaccurate rumors about the alteration of DNA by the vaccine. The mRNA vaccine will not alter DNA or manipulate the genome. The mRNA spike proteins do not enter the nucleus of any cells, including sperm cells and ovum (eggs). The mRNA vaccine will not change the structure of reproductive cells. Read the summary of recommendations included in the joint statement from ACOG, AWHONN, ACNM and ASRM regarding healthcare workers who are pregnant or considering pregnancy, along with the latest clinical guidance on fertility, pregnancy and lactation. For the latest clinical considerations for mRNA COVID-19 vaccinations, visit the CDC website.

How will you use these facts personally and in your practice?