COVID-19 Resources

COVID-19 Vaccine Facts

We know you have a lot of questions about this vaccine and about your health, and we are committed to answering them as we learn more. 


Can I get the vaccine at UC Health?

We are following the phased distribution plan set by the State of Ohio. For more information, click here.  

Can the vaccine cause COVID-19?

No. The COVID-19 mRNA and adenovirus vector vaccines do not contain the coronavirus. The mRNA vaccine works by sending a message to the cells to create a protein that looks like a piece of the surface of coronavirus. The body recognizes the foreign protein, sometimes called an antigen, and creates antibodies that protect against COVID-19.

The Johnson & Johnson adenovirus vector vaccine was created by adjusting the adenovirus 26 (a version of the common cold) to mimic the appearance and structure of COVID-19. The vector does not contain any active viruses but still serves to activate the immune system toward creating the necessary antibodies that fight the actual COVID-19 virus.

What are the side effects of the vaccine?

The vaccine is designed to trigger an immune reaction in your body. These responses are the body’s way of defending itself, and they can cause you to feel uncomfortable and sick. Therefore, you may experience mild flu-like symptoms, most commonly fatigue, headache, fever and muscle aches. You may also experience some soreness at the site of the injection. Most side effects are minor and typically go away within a few days. Less than 10% of people in the COVID-19 vaccine studies needed to take any medicines like acetaminophen (Tylenol) or ibuprofen (Motrin) to treat these symptoms. And when they did, it was typically for just a day or so.

How do we know the vaccine is safe if we don’t know the long-term effects?

The science suggests there are not likely to be longer-term side effects, but we need more time to completely confirm this. Sometimes an emergency, like the COVID-19 pandemic, demands that we take action even before we have all the safety information that we like to have before using a new vaccine.

How do we know the vaccine is safe if it was developed so quickly?

Scientists have been developing mRNA and adenovirus vector technology for decades in the hopes that it would be the future of medicine. When the pandemic began, all that was needed to create a COVID-19 vaccine was its genome — the genetic code – which scientists shared in January 2020. Similarly, scientists needed to develop a successful adenovirus 26 vector-based COVID-19 vaccine, that could pass clinical trials for the adenovirus vector vaccine to be approved. Researchers were also able to develop the COVID-19 vaccine more quickly because of the large amount of human and financial resources that were invested. It’s important to understand that this vaccine was developed and tested in the same way as other vaccines — with careful and thorough considerations for safety and effectiveness.

How does natural immunity compare to vaccine immunity?

COVID-19 is a serious disease with the potential for complications, lingering health impacts and sometimes death. A new vaccine approved through safe and strict monitoring is much safer than getting COVID-19, which we know can have grave consequences for many. Scientists are still studying how long a person is immune from COVID-19 after contracting the virus. Preliminary studies suggest natural immunity may not last very long, but more information is needed. The amounts of antibodies that neutralize or stop the virus generated by the vaccine are higher, on average, than after someone recovers from COVID-19. While scientists won’t know how long the COVID-19 vaccine lasts until more data is available, they do know the risks of COVID-19 far outweigh any immunity it may provide.

Do I need the vaccine if I’ve already had COVID-19?

Scientists are still studying how long, if at all, a person is immune from COVID-19 after contracting the virus. Preliminary studies suggest natural immunity may not last very long, but more information is needed to understand this better. If you have a previous COVID-19 infection, we encourage you to still be vaccinated.

Can I stop wearing a mask after I receive the vaccine?

No. You should continue to take precautions in certain situations. Find the CDC’s guidance for fully vaccinated individuals here.

When am I considered immune after receiving the vaccine?

You are immune seven days after the final dose.

Am I able to take other medications, such as prescriptions or over-the-counter medications, between the waiting period of the two vaccine doses?

Yes. However, please avoid taking other vaccines like the flu vaccine or shingles vaccine as this might affect how your body responds to the COVID-19 vaccine.

How many doses do I need?

It depends on which vaccine you receive. Vaccines work when you have enough antibodies (defense molecules) to stop the virus if you are exposed to it. Studies for some vaccines showed you need two doses to ensure your body has the right amount of antibodies. Other vaccines were proven effective in one dose. If you're scheduled to receive a second dose, please make sure you get it so that you can become immune to COVID-19.

Do the doses have to be exactly 21 days (for the Pfizer vaccine) or 28 days (for the Moderna vaccine) apart?

It is best that you follow the vaccine schedule proven to work. If for some reason you cannot make it back in at the right time, you should still get the second vaccine. If it is more than 30 days later, please talk to your doctor before getting the second vaccine.