FAQ: COVID-19 Vaccines

Frequently Asked Questions

Q: Is one vaccine better than another?

A: “Shopping around” for a specific vaccine brand is not recommended. All three available vaccines decrease risk of getting sick, requiring hospitalization if you do get sick, and lower your risk of death. While the Moderna and Pfizer vaccines were better in trials at preventing symptomatic illness, all three vaccines were highly effective at preventing hospitalizations and death. The best vaccine is the one that is available to you. 

Q: Can the COVID vaccine give you COVID-19?

A: No, neither the Moderna, Pfizer/BioNTech, or Johnson & Johnson vaccines contain live virus, so the vaccine cannot give you COVID-19.  The Johnson & Johnson vaccine contains an adenovirus, which is the same weakened virus used in the shingles vaccine. 

Q: Can the COVID vaccine make me test positive for COVID-19 if I take a viral test? 

A: No. The PCR and antigen tests look for an active infection. The COVID-19 vaccine cannot cause either of these tests to turn positive. If you are vaccinated and have received a positive viral test (such at the PCR or antigen test), you likely have a COVID-19 infection. Isolate from others and contact your healthcare provider. 

The vaccine may cause you to test positive on a COVID-19 antibody test, which looks for past infections, even if you have never had COVID-19. The vaccine works by stimulating your immune system to produce antibodies, which may be detected on an antibody test. Tell your healthcare provider you have received a COVID-19 vaccination prior to receiving a COVID-19 antibody test. 

Q: Are there any side effects?

A: As with any vaccination, some mild side effects can be expected. Side effects are the result of your body developing an immune response. Common side effects may include:

  • Pain, redness, or swelling at the injection site
  • Fever
  • Fatigue
  • Headache
  • Muscle/joint pain
  • Chills

Q: I already had COVID-19.  Should I still get the vaccine?

A: Yes. We know that people who have recovered from COVID-19 can become re-infected. We do not yet know how long natural infection protects against COVID-19. Vaccination is a safer way to prevent COVID-19 infections than getting sick. If you were treated for COVID-19 with monoclonal antibodies or convalescent plasma, you should wait 90 days before getting a COVID-19 vaccine. Check with your medical provider to see when you should receive the vaccine. 

Q: I just received my first dose, or I received my second dose less than 14 days ago.  Should I keep wearing a mask and social distancing? 

A: Yes, continue masking and social distancing. You are not considered "fully vaccinated" until 14 days after the last dose in your series. Once you are fully vaccinated, please see CDC guidelines, and please continue to adhere to state and local guidelines.

Q: Is it safe to get vaccinated if I have an underlying health condition?

A: Yes. COVID-19 vaccination is especially important for people with underlying health problems like heart disease, lung disease, diabetes, and obesity.  People with these conditions are more likely to get very sick from COVID-19. It is recommended that people with these conditions get vaccinated. 

Individuals who have had prior allergic reactions to injectable medicines should consult with their medical providers before receiving a COVID-19 vaccine.  

Q: Can I get the vaccine if I’m pregnant or nursing? 

A: Yes. The Pfizer/BioNTech, Moderna, and Johnson & Johnson vaccines do not contain live virus, and are considered to be safe for pregnancy and breastfeeding. 

We do know that people who are pregnant are at an increased risk for severe infections, hospitalization, and ventilation when infected with COVID-19. COVID-19 infection also increases risk for preterm birth. 

For questions about your specific medical care, talk to your healthcare provider.

Q: I’ve had allergic reactions to other shots, can I get the COVID-19 vaccine? 

A: You should talk with your provider about what allergies may make it risky for you to get the COVID-19 vaccination, but it has proven safe in the vast majority of instances. Notify your vaccinator of your allergy history prior to receiving your vaccine. You may be asked to sit in observation for 30 minutes after your vaccination if you have a history of anaphylactic reactions to vaccines. 

Q: I have a food allergy or seasonal allergies, can I get the vaccine? 

A: Yes, as stated above, allergic reactions to the COVID-19 vaccines are rare. Talk with your vaccinator or medical provider for questions specific to your care. 

Q: Is mRNA safe? 

A: Yes. Our bodies naturally make mRNA every day and it is rapidly degraded, so it does not stay in our bodies for long. mRNA is the blueprint for making proteins. It cannot change your DNA, 

The Pfizer/BioNTech and Moderna vaccines contain mRNA that gives the instructions to make the spike protein of the SARS-CoV-2 virus. This allows us to make a strong immune response to many parts of the protein without exposing us to the virus. This technology has been tested and developed over decades.

Q: I have a question about my personal medical history or my specific circumstance. Who can I talk to? 

Talk to you medical provider for any questions specific to you. You may also call 2-1-1 for help locating resources or information.

Q: What are some reputable sources for information about the COVID vaccines if I want more information? 

The Centers for Disease Control and Prevention (CDC) and the Connecticut Department of Public Health are both good sources of vaccine information. Links to their COVID-19 vaccine FAQ pages are linked below: