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Six misunderstandings about the COVID-19 vaccines, debunked

Pfizer-BioNTech COVID-19 vaccines.Jessica Rinaldi/Globe Staff/File 2021

More people are getting vaccinated against COVID-19 in Massachusetts and across the country every day. At the same time, misunderstandings — and sometimes misinformation — about the vaccines are preventing people from lining up for their shots.

Public health officials say in order to return to some semblance of pre-pandemic life, the amount of virus circulating in communities needs to drop to low levels, which can be achieved by many people getting vaccinated against the virus.

“We’re trying to get as many people vaccinated, that way we can try to keep COVID at the lowest level possible,” said Dr. Simone Wildes, an infectious disease physician at South Shore Health and a member of Governor Charlie Baker’s COVID-19 vaccine advisory group. “If we get many more people vaccinated, we can get back to whatever the new normal is going to look like.”


A nationwide poll last month by Quinnipiac University found that 68 percent of respondents said they have already been vaccinated or plan on getting vaccinated against COVID-19, while 27 percent said they don’t plan on it.

“The hardest part of the journey is always the last part. We have most people vaccinated, and it’s easy to overlook those who have not,” Wildes said. “The work has to continue to make sure we get out to these communities where they are not as receptive to vaccines as everyone else.”

Misinformation about the vaccines is circulating on social media platforms, which make it easy to share posts with family and friends, and it can be difficult to penetrate cycles of false information about vaccines in communities of color, Wildes said.

Concerns about the vaccines’ short development timeline, the technology behind it, and what it does once it’s been injected into the body are standing in the way of more people getting vaccinated.


Here’s a look at misunderstandings some may have about the vaccines, countered by information from public health experts, the Food and Drug Administration, and the Centers for Disease Control and Prevention.

The vaccines weren’t tested

Clinical trials were held to test the vaccines in tens of thousands of people to produce the scientific data required by the FDA to determine safety and effectiveness.

In the first phase of the trials, the vaccine was given to a small number of people to assess its safety. In the second phase, it was administered to more people with varying health statuses and in different demographic groups in randomized, controlled studies, which provide information on side effects and risks of the vaccine. During the final phase, the vaccine was administered to thousands of people in studies involving “broad demographic groups (i.e., the population intended for use of the vaccine),” according to the FDA.

The vaccine manufacturers conducted the trials according to rigorous standards set by the FDA and then submitted their data from the agency, which then determined whether the criteria was being met.

The FDA’s decision to briefly pause Johnson & Johnson’s COVID-19 vaccine to investigate rare instances of blood clots illustrated that the system is working and federal agencies are focused on safety, Wildes said.

“I found that very reassuring,” Wildes said. “It’s a very rigorous process and they take no shortcuts, because human rights are at stake. So people should be reassured that CDC and the FDA are doing everything they can to make sure these vaccines are safe.”


They were developed too fast

Some concerns about the COVID-19 vaccines that have been authorized stem from the fact that a highly effective vaccine was developed a few months after the virus was identified.

But the FDA notes that in public health emergencies like a global pandemic, the vaccine development process may be “atypical,” but that does not mean safety was sacrificed in the process.

During the COVID-19 pandemic, the US government assembled bodies including government agencies, nonprofit organizations, and pharmaceutical companies to develop a strategy to speed the development of the vaccines. The federal government spent billions of dollars to pay companies to begin manufacturing doses of their vaccines before they were given an emergency use authorization, allowing companies to begin distribution as soon as the vaccines were cleared.

“Efforts to speed vaccine development to address the ongoing COVID-19 pandemic have not sacrificed scientific standards, integrity of the vaccine review process, or safety,” the FDA has said.

“This did not happen in one year,” Wildes said. “The National Institute of Health and other places were working on this technology for years. It wasn’t successful, but they had this information so that when we got COVID, we were able to pivot quickly and utilize the technology.”

mRNA technology is brand new

While the COVID vaccines that are in use today are new, the technology behind them is not. Researchers have been working with mRNA vaccines for decades.

“I’ve heard so many times, which is really such misinformation that is quite frustrating, that people are focused on the fact that we got the vaccine in such rapid time,” Wildes said. “But nobody goes back to the story or the information about how they were working on this particularly technology many years ago.”


mRNA vaccines are a new type of vaccine to protect against infectious diseases, according to the CDC. The COVID-19 vaccine teaches cells how to make a piece of what is called a “spike protein,” which is found on the surface of the virus that causes COVID-19. The body’s immune system then begins building a response and making antibodies.

mRNA vaccines have been studied before for flu, Zika, rabies, and cytomegalovirus (CMV), according to the CDC, and mRNA has been used in cancer research to trigger the immune system to target specific cancer cells.

“As soon as the necessary information about the virus that causes COVID-19 was available, scientists began designing the mRNA instructions for cells to build the unique spike protein into an mRNA vaccine,” the CDC said.

The vaccines can give people COVID-19

None of the COVID-19 vaccines that have been authorized for use in the United States contain the live virus, so the vaccine cannot infect someone with COVID-19.

After people receive the vaccine they might experience side effects, like headaches, tiredness, muscle pain, chills, fever, or nausea. The side effects indicate the immune system is developing a response to fight the virus in the future, they’re not a sign of a COVID-19 infection.

“For people who think they’re getting COVID after they’ve been vaccinated, we have to remind them that they’re side effects that will go away in 24 to 48 hours,” Wildes said. “This does not have live virus, there is no way you can get COVID from the vaccine itself.”


The vaccine can impact fertility

There is no evidence that the vaccines cause any problems with pregnancy, according to the CDC. There is also no evidence that fertility problems are a side effect of any vaccine, including COVID-19 vaccines.

“If you are trying to become pregnant now or want to get pregnant in the future, you may get a COVID-19 vaccine when one is available to you,” the CDC’s website states.

“There is no data to show that the vaccine is going to make you infertile,” Wildes said. “I strongly recommend getting vaccinated because if you get pregnant and you get COVID, the effects of that can be very devastating.”

Young people don’t need to be vaccinated because the virus only affects older people

Risk for severe illness from COVID-19 increases with age, according to the CDC. But while older people are at higher risk for COVID-19, younger people are still able to get infected and become sick with the virus.

For example, as Massachusetts prioritized older people in the initial phases of its vaccination campaign, state officials warned that COVID-19 cases were increasing among younger people, particularly those under 30.

Younger people are also able to spread the virus to others and can also experience long-term side effects.

“A lot of time cases in young people are mild, but then they have long-term effects from COVID, which can be impactful for life,” Wildes said, noting that younger people who like to go out to eat might lose their sense of taste or smell, and college students might feel brain fog, which can be frustrating.

“That particular group needs to increase the number of people that get vaccinated,” she added. “They may not have severe disease, but they’re not immune, and they shouldn’t think it’s something that won’t happen to me because someone in that age group can get it and have a poor outcome.”

Amanda Kaufman can be reached at Follow her @amandakauf1.