News • Messenger RNA vaccines explained

Busting 8 common myths about Covid-19 vaccines

Even those who understand the scientific process, trust medical experts and know how important vaccines are for fighting infectious diseases might still have some questions or concerns about the new Covid-19 vaccines.

portrait of Thaddeus Stappenbeck
Thaddeus Stappenbeck, MD, PhD
Source: Cleveland Clinic

Here, Thaddeus Stappenbeck, MD, PhD, Chairman of the Department of Inflammation and Immunity at Cleveland Clinic’s Lerner Research Institute in the U.S., helps set the record straight on 8 common questions, concerns and myths that have emerged about Covid-19 vaccines, especially the newer-generation messenger RNA vaccines.

It is normal and healthy to have questions, says Stappenbeck. “These are new therapeutics and it’s totally reasonable to be asking constructive questions with an open mind,” he reassures.

Myth 1: We cannot trust Covid-19 vaccines because they were rushed

The first vaccines for Covid-19 do involve new technology, and they were developed in record time. However, it is not because there were shortcuts in the process, says Dr. Stappenbeck. He explains that the new technology at the center of Pfizer’s and Moderna’s Covid-19 vaccines is called messenger RNA, or mRNA. While this is the first time it is being widely used in a vaccine for the public, researchers have actually been working on this vaccine strategy for more than three decades. “It was a lucky thing that the technology has been robustly developed quite well over the last few years and tested in several animal models of infection, so we knew that it was safe and worked quite well in these models,” Dr. Stappenbeck says. “When Covid-19 emerged, this was an obvious opportunity to use this novel technology, and vaccine developers were poised to do it.”

The companies put their vaccines through rigorous clinical trials involving tens of thousands of volunteers. In the U.S., the Food and Drug Administration requires them to follow up with volunteers for up to two years after receiving the vaccines to make sure they are safe and effective. Because of how prevalent Covid-19 is, it only took a few months for the clinical trials to collect enough data to make an initial evaluation. 

Myth 2: The vaccine will give me Covid-19


Image source: Unsplash/Daniel Schludi

Vaccines prime your immune system to recognize and fight off a disease, but they do not actually cause an infection, says Dr. Stappenbeck. The Pfizer and Moderna vaccines contain a strand of genetic material called mRNA. When the mRNA enters your cells, it instructs them to make a piece of the “spike” protein that is present on the coronavirus that causes Covid-19. Those protein pieces do not actually harm your body, but they do trigger your immune system to mount a response to fight them off.

Dr. Stappenbeck adds that you might have some fatigue, muscle aches, a headache or a fever after you get the vaccine. He explains this is normal with any vaccine – it is a sign that your immune system is responding.

Myth 3: We do not know what is in these vaccines

Both Pfizer and Moderna have published the ingredient lists for their vaccines. In addition to the star ingredient, the Covid-19 mRNA for the spike protein, both vaccines contain lipids (fats) that help deliver the mRNA into your cells and a few other common ingredients that help maintain the pH and stability of the vaccine. They do not contain microchips or any form of tracking device.

Myth 4: These vaccines will alter my DNA

The vaccines use mRNA to instruct our cells to make a piece of the coronavirus’s hallmark spike protein in order to spark an immune system response. Once the mRNA does that, our cells break it down and get rid of it. “Messenger RNA is something that’s made from DNA, but it’s not designed to integrate with our DNA, and it doesn’t permanently change our genome and who we are in any way,” Dr. Stappenbeck says.

Myth 5: I already had Covid-19, so I will not benefit from the vaccine

Right now, it seems that getting Covid-19 more than once is not common, but there are still many questions that remain unanswered

Thaddeus Stappenbeck

We do not yet know how long natural immunity to Covid-19 lasts, Dr. Stappenbeck says. “Right now, it seems that getting Covid-19 more than once is not common, but there are still many questions that remain unanswered. Experts say that, even if you’ve had Covid-19, it would still be appropriate for you to get the vaccine to make sure you’re protected.”

Myth 6: Since Covid-19’s survival rate is so high, I don’t need a vaccine

It is true that most people who get Covid-19 are able to recover, however, Dr. Stappenbeck points out, it is also true that some people develop severe complications. So far, close to 2 million people around the world have died from Covid-19 – and that does not account for people who survived but needed to be hospitalized. As the disease can damage the lungs, heart and brain, it may also cause long-term health problems that experts are still working to understand.

Dr. Stappenbeck adds that there is another reason to consider getting the vaccine: It protects those around you. “Even if Covid-19 doesn’t make you very sick, you could pass it on to someone else who might be more severely affected. Widespread vaccination protects populations, including those who are most at risk and those who can’t be vaccinated. It will be important for ending the pandemic.”

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Myth 7: Once I get the vaccine, I won’t have to wear a mask or worry about social distancing

Even if you get the vaccine, you should continue to wear a mask around others, wash your hands and practice physical distancing. Dr. Stappenbeck says there are a few reasons for this. The first is that both the Pfizer and the Moderna vaccines require two doses given three to four weeks apart to achieve the best possible immunity. When you get your first shot, you do not become immediately immune. “It takes at least a week to 10 days for your body to begin to develop antibodies, and then those antibodies continue to increase over the next several weeks,” Dr. Stappenbeck says.

The second is that these vaccines were developed and tested for their ability to prevent severe illness and death from Covid-19. It is not clear whether they also protect against asymptomatic infection and spread. “There will be ongoing studies to evaluate this question, but it will be some time before we actually know,” Dr. Stappenbeck says. “So after you get the vaccine, you should still take steps to protect other people who haven’t been vaccinated yet.”

Image source: Pexels/Ethan Wilkinson

Myth 8: Now that we have vaccines, the pandemic will be over very soon

“I would love to say that we’re going to flip a switch and everything’s going to be back to normal, but it’s actually going to take a long time for us to be able to vaccinate an adequate number of people to where we’ll start to see the cases really dropping,” Dr. Stappenbeck explains.

In order to achieve what’s called herd immunity – the point at which the disease is no longer likely to spread – about 70% of the population will need to have been vaccinated or infected, he says. But the companies that manufacture these vaccines can only make so many at a time. So the vaccines will be distributed in phases, with priority given to people with greatest need, They may not be widely available to the general public until several months into 2021.

For now, we should all continue to do our part to help slow the spread of the virus, including wearing a mask, washing our hands and physical distancing, Dr. Stappenbeck says.

Source: Cleveland Clinic


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