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COVID-19 vaccine myth-busters

Get the truth about the vaccine.

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As health care systems across the country work rapidly to distribute COVID-19 vaccines as efficiently as possible, there is a lot of information that is being shared on social media and online. Some of this information may be creating fears over the vaccines and influencing the decision of whether to get vaccinated or not. Sankar Swaminathan, M.D., chief of the Division of Infectious Diseases at University of Utah Health, sets the record straight on some of the myths about COVID-19 vaccines.

MYTH: Development of the vaccine was rushed

FACT: While it was done quickly, it was not rushed. The term “rushed” suggests something was done differently than normal or that corners were cut. In fact, tens of thousands of participants were studied in the safety and efficacy trials. In a normal vaccine trial, enough people have to get the disease to know whether it works or not. This often means waiting for a long time. With COVID-19, because the virus was so widespread, and disease occurs soon after infection, it was possible to complete the studies much sooner. The development of these vaccines was also based on a wealth of scientific work that had been done previously in the laboratory and in animals.

MYTH: One vaccine (Pfizer/BioNtech or Modera) is better than the other

FACT: Both vaccines are very similar and based on the same technology. People should get whichever vaccine is offered to them as soon as possible.

MYTH: mRNA cannot be trusted because it’s a new type of vaccine

FACT: Messenger RNA is a small molecule that is made by cells in your body and by bacteria and viruses. It’s a blueprint for how to make a protein. The Moderna and Pfizer/BioNTech vaccines consist of mRNA that’s been made in the lab. When it gets in your cells, the mRNA instructs them to make a version of the spike protein that SARS-CoV-2 makes. This small, harmless piece of the virus is not enough to cause COVID-19. This is just a clever way of introducing the spike protein into your body so the body can learn how to fight it off. It’s similar in that way to a tetanus shot, where instead of mRNA you actually inject the tetanus protein. Learn more about COVID-19 mRNA vaccines here.

While it is true that mRNA vaccines have not been widely used before, these two vaccines have been tested in tens of thousands of people to demonstrate both safety and efficacy. We still need to determine the long-term efficacy and whether there are rare side effects when used in hundreds of millions of people. Currently, these vaccines are effective, safe, and the best option to prevent millions of infections and deaths.

MYTH: The second dose of the vaccine is not needed

FACT: You need two doses of the vaccine because that is what was studied and shown to work for immunity. We don’t know how effective or durable protection from a single dose would be. When you get first exposed to a vaccine or a foreign substance, your body generates cells that can recognize that foreign substance. The second time you get exposed, you develop a stronger immunity and build long-term immunity. What you generally find is the response after the second dose is much larger in magnitude and longer-lasting.

MYTH: The vaccine will not protect against new COVID-19 variants

FACT: Not necessarily. It is normal for viruses to mutate. The term “variant” refers to versions of the virus with new mutations. In the case of the U.K. variant that has been in the news, we expect the vaccine will protect against it. But moving forward, vaccine efficacy could lessen as more variants emerge over time. This is why it’s important to get the population vaccinated and limit transmission as soon as possible.

MYTH: Health care workers are getting the vaccine first because they are more important

FACT: The Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and the Advisory Committee on Immunization Practices (ACIP) identified health care personnel (HCP) as the first group to receive the vaccine, as well as residents in longer-term health care facilities. This is often referred to as Phase 1A.

Health care personnel at U of U Health who are working on the frontlines of the COVID-19 pandemic and who are most at risk of exposure to the virus have been identified in this initial group. Prioritizing this group ensures the U of U Health care systems can continue taking care of patients.

MYTH: Older adults with poor health should not get the vaccine

FACT: It is even more important for older adults to get vaccinated. This group is at higher risk of hospitalization, experiencing complications from the virus, and even death. Moderna and Pfizer/BioNTech trials (~10,000 people between the ages of 65-90 participated) showed the vaccines were safe and just as effective in this age group.

A COVID-19 vaccine will lower your risk of getting sick if you are exposed to the virus. It’s possible to still contract COVID-19 after receiving the vaccine, but evidence suggests the vaccine may keep you from getting seriously ill if you get infected. Getting the vaccine may also help protect the people you’re around, especially those who are at increased risk of becoming seriously ill from COVID-19.

MYTH: Those who have allergies should not get the vaccine

FACT: Out of the tens of thousands of people who were tested in the initial COVID-19 vaccine trial, there were no serious adverse effects. Now that the vaccine has been given to a few million people in the U.S., there has been a very small number of adverse effects. Fewer than a dozen out of the one million who received the Pfizer/BioNTech vaccine experienced anaphylactic reactions. They recovered after treatment and had no long-term effects. There’s always the possibility that as more people become immunized, we find some rare side effects.

If you’ve had a previous severe allergic reaction such as face swelling, difficulty breathing, or had to be treated with an epi-pen after vaccination, then you should discuss with your doctor whether it’s safe to get the COVID-19 vaccine. Common allergies like hay fever or food allergies are not a reason to avoid the vaccine. You have a greater chance of experiencing long-term side effects or dying from COVID-19 than experiencing an adverse reaction to the vaccine.

MYTH: You don’t need to get the vaccine if you’ve already had COVID

FACT: Those who already had COVID-19 should get vaccinated. Duration of immunity from natural infection of the virus is not known at this time. In some cases, people have reported getting COVID-19 twice. The CDC recommends getting the vaccine due to the severe health risks associated with COVID-19 and the fact that re-infection with COVID-19 is possible.

MYTH: The vaccine can harm fertility or pregnancy

FACT: There is no reason to think the vaccine will harm fertility, but it has not been tested in pregnant women. Pregnant women have an increased risk for severe illness from COVID-19 and there is a risk for moms transmitting COVID-19 to babies, likely after birth and not during pregnancy. Therefore, it could be beneficial to get the vaccine. Those who are pregnant should consult with their obstetrician and discuss whether the vaccine is appropriate for them.

MYTH: COVID-19 vaccines can make you sick

FACT: COVID-19 vaccines cannot make you sick with COVID-19, but it is still possible to get the virus after getting the first dose of the vaccine. Because the second dose of the vaccine boosts your immune system, a patient is more likely to experience side effects. Some symptoms include injection site pain, muscle aches, chills, fatigue, and fever. These side effects can be treated with over-the-counter medication.

MYTH: You can ditch the mask after getting vaccinated

FACT: Two weeks after the second dose, there is 95% protection from becoming ill. Even though you likely won’t get sick from the virus, we don’t have clear evidence at this time that the vaccine protects you from getting infected or prevents you from infecting others. Until we get to a point of limited community transmission, people who are immunized should continue to take precautions that they normally take: wear a mask, physically distance, and regularly wash your hands. At this time, the CDC and other public health agencies will update their guidelines.