How Is the Vaccine Given?

Both the Pfizer/BioNTech and Moderna vaccines are given via two shots. The first dose starts building protection against the virus and the second dose gives you the most protection. Both doses are needed to fully protect you from getting sick with COVID-19. The Janssen (a Johnson & Johnson company) vaccine only requires one dose for full protection.


When do I have to receive the second dose?

Pfizer/BioNTech doses are given 21 days apart and Moderna doses are given 28 days apart. The second doses should be administered as close to the recommended time frames as possible. 

What if I can’t receive the second dose within the recommended time frame?

Testing has shown that the second dose is just as effective when given up to 42 days after the first dose. However, it is still best to get your second dose within the recommended time frame. According to the Centers for Disease Control and Prevention (CDC), even second doses given four days earlier than the recommended date are still considered effective.

Can I get my first dose from Pfizer/BioNTech and my second dose from Moderna or vice versa?

This is not recommended. Both doses you receive need to be manufactured by the same company. At this time, we do not know whether combining vaccines by various manufacturers will give you the same protection against COVID-19.

How long does vaccine immunity take?

The full immune response appears to be reached two weeks after the second dose of Pfizer/BioNTech or Moderna vaccine. The Johnson & Johnson vaccine takes about four weeks for full protection against COVID-19 (two weeks after vaccination for protection against mild to severe disease).

Vaccine Considerations for Specific Groups of People

Can my child or teen get the vaccine?

The vaccines have not been widely tested on children. Vaccine manufacturers only recently started including children as young as six months in their trials. At this time, we don’t know how the vaccine affects people in these age groups. The Pfizer/BioNTech vaccine has only been authorized for use in people 12 years of age and older, however, the Moderna and Janssen (Johnson & Johnson) vaccines have only been authorized for people age 18 and older.

I'm pregnant. Will the vaccine harm me or my baby?

Getting infected with COVID-19 while you're pregnant puts you at an increased risk of developing severe illness, giving birth prematurely, and pregnancy complications. People who are pregnant or lactating (producing breast milk) can currently receive any of the FDA-authorized COVID-19 vaccines.

Based on early data, no safety concerns were seen in pregnant people who were vaccinated or their babies. At this time, we don’t have enough information about how the vaccine may affect people who are breastfeeding or the effects of COVID-19 on breastfed infants, milk production, or excretion. 

If you are pregnant, lactating, or in the postpartum stage and under the age of 50, there is a rare risk of developing TTS after getting the Johnson & Johnson vaccine. However, there are other COVID-19 vaccines available to you that do not carry this same risk. Talk to your health care provider first if you have questions about the vaccine or choosing the right one for you.

I'm over the age of 65. Is the vaccine safe for me? 

The current CDC recommendations are to vaccinate all adults (regardless of other risks) age 65 and older. The most recent data from clinical trials shows that the vaccine was very effective (better than 90 percent) in protecting people 65 years and older. The rate of harmful reactions in older adults has also been low — likely lower than the flu vaccine. At this time, there is not a lot of information on adults who are 90 years of age and older. If you have questions about the vaccine, consult with your doctor.

If You Currently Have COVID-19

Can I still get the vaccine if I am experiencing COVID-19 symptoms?

If you have COVID-19 symptoms and have not been vaccinated yet, isolate yourself and get tested immediately. You may be vaccinated after you have recovered from COVID-19 and your isolation period is over. COVID-19 vaccines do not interfere with the results of a COVID-19 test.

What if I get COVID-19 in between doses?

If you tested positive for COVID-19 after your first dose of the Pfizer/BioNTech or Moderna vaccine, you must:

  • wait until you are finished isolating (10 days for people with or without symptoms) and
  • wait until you don’t have any symptoms (three days without symptoms) before your second dose.

It doesn’t matter if you’ve been infected with COVID-19 before, clinical data shows that the Pfizer/BioNTech and Moderna vaccines only provide complete protection from COVID-19 after two doses. People with long-term COVID-19 symptoms should talk to their doctor before getting vaccinated. 

Exposed to COVID-19 After Vaccination

I was exposed to someone who tested positive with COVID-19. Do I need to quarantine if I’m fully vaccinated?

You could still get sick from COVID-19 if you were exposed to the virus:

  • before getting your second dose of the Pfizer/BioNTech or Moderna vaccine or
  • before your body developed full immunity.

You do not need to quarantine if:

  • it has been two weeks since you received the second dose of Pfizer/BioNTech or Moderna vaccine.
  • it has been at least two weeks since you received the Janssen (a Johnson & Johnson company) vaccine. 

However, if you get symptoms of COVID-19 after you were exposed, call your doctor or health care provider.

I'm Fully Vaccinated. What Activities Can I Do?

Clinical trials show the vaccines will protect you from getting ill from COVID-19. Fully vaccinated people can resume indoor and outdoor activities without wearing a mask or physically distancing from others, except in healthcare settings, according to CDC guidelines.

However, you will need to wear a mask when required by laws, rules, or regulations, including local business and workplace policies.

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