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Vaccine FAQs: Common Myths and Misconceptions

1. The Vaccines were produced so quickly, how do we know if they are safe?

The Pfizer and Moderna vaccines, which use mRNA, have been in development for more than 30 years, and have gone through clinical trials before COVID, targeting other coronaviruses; the COVID-19 clinical trials have been among the largest in medical history. Additionally, we know more about these vaccines than any vaccine ever before in advance of full FDA approval; as of this printing, more than 330 million vaccine doses have been administered in the United States — and more than a billion people around the world — have taken a COVID vaccine. No other vaccine has had so much preliminary data for the FDA to review and approve.

America’s drug safety system works. The pause of the Johnson & Johnson vaccine earlier this year shows that even rare complications or concerns will be immediately investigated and publicized.

Those participating in these trials are still being carefully monitored, and no long-term negative effects have been noted. All current COVID-19 vaccines are proven to prevent serious COVID-related hospitalizations and death nearly 100% of the time. Often, people don’t hear this positive (even amazing) news, as headlines tend to focus on negatives because more people will read or watch negative news.

Additionally, the first individuals who were encouraged to be vaccinated, and then voluntarily received the vaccine, were healthcare workers. Healthcare workers know the risks of COVID-19. And no company, organization, government or even individual would benefit from harming the U.S. healthcare workforce. If the vaccines weren’t safe, healthcare workers wouldn’t have been encouraged to take them.

2. Are there fertility risks with these vaccines?

There is no evidence at all that any of the COVID-19 vaccines prevent conception or lead to miscarriages, problems in pregnancy or birth defects.  A pregnancy/vaccine-related study was published June 17, 2021, in the New England Journal of Medicine.  The study included more than 30,000 US women who were pregnant at the time of vaccination, and more than 5,000 who have become pregnant since being vaccinated; those participating in studies after receiving the mRNA COVID-19 vaccines show outcomes that correlate with pregnancies in 2019, prior to the pandemic. There were no major safety concerns to mother or child from either of the mRNA COVID-19 vaccines. 

It should be noted that pregnancy itself is a high-risk condition for COVID-19, with increased risk for complications. A growing baby requires a great deal of oxygen, and when a pregnant woman’s lungs are compromised from COVID-19, it can lead to poor outcomes including the mother being hospitalized and ventilated, pre-term labor, and death of the mother and/or baby. Women who have COVID-19 while pregnant are also at higher risk of having long-term symptoms (often called “long COVID”), making postpartum recovery and caring for an infant more difficult. 

Leading obstetric and reproductive professional organizations have recommended that pregnant or childbearing-age women be vaccinated for COVID-19.  None of these groups would make this recommendation if they believed the vaccine presented a risk a woman’s ability to become pregnant or to have a healthy pregnancy.  You can read statements from the largest professional group of OB/GYNS at

Additionally, vaccination during pregnancy may also protect the baby after birth.  Some of the COVID-19 variants that are now circulating in the US have caused many deaths in infants in countries where the variants have spread.

3. Can the vaccine alter your DNA?

The mRNA from the vaccine does not enter the nucleus of the cell (where your DNA is stored), so it cannot change your DNA.

4. How long does the mRNA stick around in the cell?

mRNA is quickly read by ribosomes (proteins in the cell) and translated into the spike protein that leads the body to develop antibodies. It is broken down immediately after the cell makes the spike protein.

In fact, mRNA breaks down very quickly in general and is not stable for long at normal temperatures, which is why there are such strict storage requirements for some of these vaccines. For example, the vaccine from Pfizer must be stored at -70°C to be stable longer- term. Once refrigerated, it is only good for 5 days, and at room temperature for only about 12 hours.

5. Can the vaccine make me sick with COVID-19?

No.  None of the currently authorized vaccines contain the virus that causes COVID-19.  This means that a COVID-19 vaccine cannot make you sick with COVID-19.

However, people can be exposed to the coronavirus [that causes COVID-19] shortly before or right after getting the vaccine, and become ill from that exposure.  But the vaccine cannot infect someone with COVID-19.

6. If I’ve already had COVID, why should I get vaccinated?

A more comprehensive blog article on this topic has been published at, but here are some of the key points from it:

  • Natural immunity wanes.  Natural immunity results from the antibodies made by a person’s immune system when they’re infected with a particular pathogen.  When someone is infected with COVID-19, they do develop antibodies to the SAR-CoV-2 virus (the virus that causes the COVID-19 infection).  But over time, those antibodies begin to reduce in number. This process is different from person-to-person, and impossible to predict.  Additionally, the only way to maintain antibodies against the virus long-term is to get vaccinated, or to become infected again.
  • Natural immunity may not adequately protect against variants. The genetic make-up of viruses changes and evolves over time.  (For example, the flu changes each year, requiring a somewhat different shot every fall.) SAR-CoV-2 is doing the same thing, and prior infection from earlier variants of the virus may not offer the same protection for new variants. Immunity from vaccination, however, offers broader coverage because it creates antibodies to the protein on the outside of the virus, which is remaining more consistent. According to a recent study among Kentucky residents, those who were previously infected with an earlier form of the SARS-CoV-2 virus who are unvaccinated are more than twice as likely to be infected as someone who was previously infected but is also vaccinated.
7. I’ve already been vaccinated. Why do I have to wear a mask?

Those who are vaccinated can still become infected enough to spread the virus to others, although this appears to be for a lower rate and for a shorter period of time.  Again, NO vaccine is 100% effective in preventing infection.  Vaccines work because if enough people get vaccinated, viruses run out of humans to whom they can spread; this is called herd immunity, and we are nowhere near herd immunity here in our region. 

Masking is also imperfect, but masks reduce the number of airborne droplets that are released from your mouth and nose, keeping the viral load in the air lower. Lower viral loads can help reduce the likelihood of infecting others, as well as severity of illness if they do become infected.

Vaccination, masking and social distancing (limiting gatherings, staying outside and spaced apart)—used all together—are going to be the best way to get past these difficult times.

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