10 Myths About Coronavirus Vaccines

Separating fact from fiction when it comes to getting vaccinated against Covid.

More than 207 million Americans have rolled up their sleeves for the coronavirus vaccines, but still a significant share of the eligible population hasn’t been vaccinated.

A big reason: False information spread online and in person has persuaded many people to skip the shot. In fact, a recent Kaiser Family Foundation report found about 80 percent of adults who say they will “definitely not” get the vaccine believe or are unsure about at least one prevailing COVID-19 vaccine myth. And a majority of adults (54 percent) either believe some rampant misinformation about the COVID-19 vaccines or are unable to debunk it.

Facts are especially important as new COVID-19 cases, hospitalizations and deaths climb throughout the U.S., driven largely by the highly contagious delta variant. Here are some common coronavirus vaccine myths and the truth behind each one.

  • Myth #1: The vaccines were developed too quickly to be trusted.

It’s true that the COVID-19 vaccines arrived in record time, but the steps that were hurried “were essentially the paperwork,” Andrew Bradley, M.D., a vaccine expert and professor at Mayo Clinic, explained in a recent media briefing.

All three available vaccines in the U.S. — from Pfizer-BioNTech, Moderna and Johnson & Johnson — were tested in tens of thousands of people in clinical trials and rigorously evaluated for their safety and effectiveness.

Scientists had a bit of a leg-up from the beginning, which helped to accelerate the process. The virus that causes COVID-19 is related to other coronaviruses that have been under the microscope for years, including those that cause severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). “The knowledge gained through past research on coronavirus vaccines helped to accelerate the initial development of the current COVID-19 vaccines,” the Centers for Disease Control and Prevention (CDC) says.

Investing in early manufacturing and distribution also got shots in arms faster than usual.

And while two of the vaccines (Pfizer’s and Moderna’s) are a new type of vaccine, called mRNA, researchers have been studying the technology for decades across a range of diseases, including flu, Zika and rabies — even cancer. This type of vaccine delivers a set of instructions to the cells and teaches them to make a protein that then produces an immune response to the virus.

Pfizer’s COVID-19 vaccine recently received full approval from the U.S. Food and Drug Administration (FDA) and Moderna’s will likely get it soon. Johnson & Johnson — whose vaccine is a viral vector vaccine, meaning it uses a modified version of a different virus to deliver those immune-triggering directions — is expected to apply for federal approval soon. Both the Moderna and the Johnson & Johnson vaccines continue to be administered under the FDA’s emergency use authorization (EUA).

Myth #2: The vaccines will alter your DNA.

None of the vaccines interact with or alter a person’s genetic material, known as DNA, the CDC confirms. The vaccines help the cells build protection against a coronavirus infection, but the vaccine material never enters the nucleus of the cell where the DNA lives.

When it comes to the mRNA vaccines, after the cell is done using the instructions delivered, it breaks down and gets rid of the mRNA. And the genetic material delivered by the viral vector (used in the Johnson & Johnson vaccine) does not integrate into a person’s DNA, the CDC says.

Myth #3: If you’ve had COVID-19 already, you don’t need to get vaccinated.

Even if you’ve had COVID-19, experts recommend getting vaccinated.

One reason: It’s unclear how long you are protected from the disease after a previous infection. Another: New research suggests that the COVID-19 vaccines offer better protection than natural immunity and can help prevent reinfections.

A study published Aug. 13 by the CDC found that unvaccinated individuals who already had COVID-19 were more than twice as likely as fully vaccinated people to get COVID-19 again. And research published this year in The Lancet suggests that older adults are more likely to be reinfected with COVID-19 than younger populations — a difference that can likely be explained by natural changes that weaken the immune system as you age, the authors note.

If you had COVID-19 and you were treated with monoclonal antibodies or convalescent plasma, the CDC recommends waiting 90 days before getting the vaccine.

Myth #4: Once you receive the coronavirus vaccine, you’re immune for life.

Health experts are still studying how long immunity lasts after vaccination, but additional shots that increase protection against COVID-19 may be needed over time — especially as new virus strains, like the dangerous delta variant, emerge and circulate. A third dose of the Pfizer and Moderna vaccines is already being recommended for certain people with compromised immune systems.

While specifics are still unknown, the U.S. Department of Health and Human Services (HHS) has announced plans for a booster rollout as early as this fall if recommended by the CDC’s independent advisory committee. If approved, more vulnerable populations such as older adults and health care workers will likely be first in line for the shots.

“We need to see much more data to see what the benefits of boosting [are] to the overarching general population who are lower risk” for severe COVID-19, Cameron Wolfe, M.D., infectious disease specialist and associate professor at the Duke University School of Medicine, said in a recent news briefing on the subject.

The need for boosters, however, does not mean that the vaccines are not working. So far, the data show that they have been highly protective at preventing hospitalizations and death from COVID-19.

Myth #5: You can ditch your mask after you get vaccinated.

People who have been fully vaccinated can resume many pre-pandemic activities, but going completely mask-free isn’t recommended. The CDC is still encouraging everyone, regardless of vaccination status, to wear a mask in public indoor settings in order to curtail the spread of the virus.

The reason? New research shows that while fully vaccinated people are remarkably protected from serious illness if infected with the delta variant, it’s possible for them to spread the virus to others, including someone who is unvaccinated or immunocompromised. The guidelines are mostly for people in areas of high or substantial virus transmission. Currently, that’s 97 percent of U.S. counties, according to the CDC.

Myth #6: The vaccines use a live version of the coronavirus.

None of the authorized vaccines in the U.S. use the live virus that causes COVID-19, and they cannot give you the disease or cause you to test positive for a coronavirus infection. Instead, the vaccines use scientific techniques to train the human body to recognize and fight the coronavirus.

The Pfizer-BioNTech and Moderna vaccines deliver a set of instructions to your cells to encourage your body to produce antibodies. The Johnson & Johnson vaccine works differently. It uses a harmless adenovirus that can no longer replicate to send a genetic message to your cells.

While the coronavirus vaccines will not make you sick with COVID-19, they can cause side effects in some people. Commonly reported side effects include injection-site pain, fatigue, headache, chills, fever and muscle aches. Most of the reactions are temporary and resolve within a few days, according to the CDC.

Myth #7: You don’t need both doses of the two-dose vaccines.

Both the Moderna and the Pfizer-BioNTech vaccines require two doses that are given a few weeks apart. And experts stress that both shots are needed for optimal protection.

study published by the CDC in May found that a single dose of the Pfizer or Moderna vaccines were about 80 percent effective against symptomatic COVID-19; two doses were 94 percent effective.

Delta’s rise to dominance may make that second shot even more important. A U.K.-based study recently published in The New England Journal of Medicine found that one dose of the Pfizer vaccine or AstraZeneca vaccine (which is not currently authorized in the U.S.) is about 31 percent effective against symptomatic disease caused by delta. Two vaccine doses were about 88 percent effective.

The second Pfizer shot should be given 21 days after the first, the CDC recommends. Moderna’s doses should be administered 28 days apart. That said, the second dose of either may be given up to six weeks (42 days) from the first, if necessary.

Myth #8: The vaccines contain microchips or can cause you to be magnetic.

These two rumors have been circulating on social media, but neither one is true. “Vaccines are developed to fight against disease and are not administered to track your movement,” the CDC says. What’s more, the vaccines do not contain any metals or materials that can produce an electromagnetic field.

They are also free from manufactured products such as microelectronics, electrodes, carbon nanotubes or nanowire semiconductors, and from eggs, gelatin, latex and preservatives.

Find out more about the ingredients in the vaccines here.

Myth #9: The vaccines can cause fertility problems.

There is currently no evidence that any vaccines, including the COVID-19 vaccines, cause fertility problems in women or men, the CDC says. And in fact vaccination is recommended for people who are breastfeeding, pregnant or plan to get pregnant in the future.

The National Institutes of Health did recently award research grants to five institutions to explore potential links between COVID-19 vaccination and menstrual changes after some women reported experiencing irregular or missing periods after getting the shot.

A number of factors can lead to temporary changes in periods. Immune responses to the COVID-19 vaccine is one explanation. Others include pandemic-related stress, lifestyle changes related to the pandemic and infection with SARS-CoV-2, the NIH writes.

“These rigorous scientific studies will improve our understanding of the potential effects of COVID-19 vaccines on menstruation, giving people who menstruate more information about what to expect after vaccination and potentially reducing vaccine hesitancy,” Diana W. Bianchi, M.D., director of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, said in a statement.

Myth #10: You shouldn’t get the vaccine if you’ve ever had an allergic reaction.

If you have a history of allergic reactions to oral medications, food, pets, insect stings, latex or things in the environment like pollen or dust, you can safely get the COVID-19 vaccine, the CDC says. You can also get the vaccines if you have an egg allergy, because none of the authorized vaccines contain eggs or egg-related components.

The only group the agency says should definitely abstain are those who have had a severe allergic reaction to any ingredient in a COVID-19 vaccine. If you’ve had an allergic reaction to other vaccines or to injectable medications, the CDC recommends talking to your medical provider about whether to get the vaccine.

Only a small number of the people who have received a COVID-19 vaccine so far experienced the severe allergic reaction called anaphylaxis. Anaphylaxis has affected about two to five people per million vaccinated, the CDC says. Although anaphylaxis is life-threatening, it almost always occurs within 30 minutes of vaccination and can be quickly halted with a medicine such as epinephrine.

The agency recommends that people with a history of anaphylaxis stay on site for observation for 30 minutes after vaccination. Those with no history of anaphylaxis should stay for 15 minutes.

For the latest coronavirus news and advice go to AARP.org/coronavirus.