nurse putting bandage on arm
nurse putting bandage on arm

5 Reasons We Know The COVID-19 Vaccines Don't Have Long-Term Health Effects

Posted on February 1, 2022 by Henry Ford Health Staff

The development of the COVID-19 vaccines has been a significant achievement in modern medicine. Thanks to incredible scientific advancements—along with expedited funding, thousands of volunteers willing to participate in clinical trials, and the ability to quickly recruit scientists from around the world—the vaccines were safely brought to market in record time. (Emphasis on the word safely. Clinical trials, research and studies were not sacrificed in the creation of the COVID-19 vaccines.)

And not only that: the COVID-19 vaccines are some of the most effective vaccines that have ever been created, only to be rivaled by the smallpox and measles vaccines, says Dennis Cunningham, M.D., medical director of infection control and prevention with Henry Ford Health.

Yet a perpetual worry that’s fueling vaccine hesitancy is the question of long-term health effects. “The only long-term effect of the COVID-19 vaccines is survival,” says Dr. Cunningham. “There are no adverse long-term effects to worry about. Contracting COVID-19, however, can leave you with lingering health problems.” 

Here he shares five reasons we know the COVID-19 vaccines won’t cause long-term health effects. 

1. History has showed us that with vaccines, adverse effects occur within eight weeks of vaccination—not years later. “These COVID-19 vaccines have been given to hundreds of millions of people for more than a year, so we know they are extremely safe,” says Dr. Cunningham. “You are much, much more likely to be hospitalized from COVID-19 than you are to have an adverse reaction from the vaccines.”

2. Neither mRNA technology—nor viral vector technology—is new. The Johnson & Johnson vaccine was created using viral vector technology, which has already safely been used in Ebola vaccines. The Pfizer and Moderna vaccines were created using messenger RNA (or mRNA) technology, which has been used for about 10 years in cancer treatment, with no long-term effects detected. And even before that, scientists had been working with mRNA technology for years.

3. mRNA technology does not alter your DNA. One persistent myth is that the mRNA vaccines could alter your DNA in the long-term. But this isn’t possible, as mRNA disintegrates quickly and doesn’t get anywhere near our DNA.

“The mRNA in the COVID-19 vaccines contains the instructions to create COVID-19’s spike protein,” says Dr. Cunningham. “Our bodies then make this protein, recognize it as foreign, and create antibodies to protect against it. If you are exposed to COVID-19 in the future, your body will remember how to defend itself against infection. mRNA doesn’t get close to the nucleus of our cells where our DNA is created and it breaks down quickly after the ‘message’ is received.”

4. As opposed to other types of treatments and medications that are taken regularly, vaccines can’t cause a surprise reaction years down the road. Medications that are used to manage chronic conditions are monitored by the FDA for long-term effects for years. They are completely different from vaccines, which don’t significantly or permanently alter biologic functions—nor are they used routinely.

“With vaccines, you’ll get one or two shots (maybe even three if you get a booster),” says Dr. Cunningham. “If you are going to get a reaction from a vaccine, it’s going to occur soon after you receive the vaccine. At most, it will occur within two months—not 10 years later.”

5. The mRNA vaccines might feel futuristic, but their ingredients actually are not. Almost all of the ingredients in the COVID-19 vaccines are ingredients found in foods: fats, sugars and salts, says the Centers for Disease Control and Prevention (CDC). If you are allergic to any of the ingredients in the vaccines, you should not get vaccinated. But for everyone else—and that’s the vast majority of the population—these ingredients are safe.

While mRNA isn’t found in food, it is natural: our bodies already make mRNA. (That’s how we make proteins.) The mRNA in the vaccines is just a small piece of external mRNA. After vaccination—after we mount an immune response—our bodies discard the mRNA, right along with the rest of the ingredients in the vaccine, merely leaving us with the tools to defend ourselves against contracting COVID-19.

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Henry Ford offers COVID-19 vaccines and boosters to established patients. Appointments can be scheduled in MyChart. For updates on booster guidelines and availability of vaccines by age group, visit  

To find a doctor at Henry Ford, visit or call 1-800-436-7936.

Dr. Dennis Cunningham is the medical director of infection control and prevention at Henry Ford Health.   

Categories : FeelWell

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