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 Johson & 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.

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).

COVID-19 Vaccination & Other Types of Vaccines

I recently received a flu (or other) vaccine. Can I still get the COVID-19 vaccine?

You must wait at least 14 days before receiving any of the COVID-19 vaccines. If you need to receive another type of vaccine after your first dose of Pfizer/BioNtech or Moderna vaccine, you still must wait 14 days unless your physician advises differently. Clinical trials show the second dose of the Pfizer/BioNTech or Moderna vaccine is effective if given up to 42 days after the first dose.

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.

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. 

Since COVID-19 gives you some immunity, it is requested that you wait 90 days before getting your first dose of the vaccine. Because there is limited vaccine supply, this allows the people who do not yet have immunity to get the vaccine.

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.

Even though the vaccines prevent you from becoming ill with COVID-19, we do not yet know if they will protect you from becoming infected with the virus and transmitting it to other people.

After vaccination, it is important that you continue to:

  • wear a mask,
  • stay six feet apart,
  • wash your hands, and
  • avoid crowds.

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