Your Guide to COVID-19 Vaccination

What is COVID-19?

COVID-19 is a disease caused by SARS-CoV-2, a virus that is part of the coronavirus family. COVID-19 can be transmitted from person to person and causes symptoms that can range from mild to severe, including death in a small percentage of cases. The infection can also be carried and transmitted by some without symptoms.

What are the Pfizer/BioNTech and Moderna vaccines?

The Pfizer/BioNTech and Moderna vaccines are intramuscular injections which include a small amount of material from the SARS-CoV-2 virus. Our body uses this material to generate an immune response against the virus, should you be exposed in the future.

These vaccines have been granted Emergency Use Authorization by the FDA, but are not considered FDA-approved. They are appropriate for people 16+ (Pfizer)/18+ years of age (Moderna).

How is the vaccine given?

The vaccine is given as an injection into the muscle. The Pfizer/BioNtech vaccine series is two doses given at least 21 days apart. The Moderna vaccine series is two doses given at least 28 days apart. Your second dose must be the same vaccine (Pfizer/BioNTech or Moderna) as you received for the first dose.

Can I receive the Pfizer/BioNTech or Moderna vaccine with other vaccines?

You should not get a COVID-19 vaccine if you have had any other vaccine in the 14 days prior.

What are the benefits of the COVID-19 vaccine?

Both the Pfizer/BioNTech and Moderna vaccines have been shown to be over 90% effective in preventing illness from COVID-19. How long this protection lasts is currently unknown.

Once fully vaccinated, for the first 3 months afterwards, you do not need to quarantine if you are exposed to someone with COVID-19.

If I get vaccinated, when am I considered immune to COVID-19?

Based on early data, the vaccines look like they're extremely effective, so once you've received the full vaccine series (i.e. two shots) and your immune system has had an additional 7 days or more to respond, you're very likely to be protected from getting sick. It is unknown yet if those who are immune can still transmit the virus. Since no vaccine is 100% effective, we'll all need to continue wearing masks and maintaining physical distance from others well into 2021.

What are the potential harms from the COVID-19 vaccine?

Side effects that have been reported with the Pfizer/BioNTech and Moderna COVID-19 vaccines are similar to most other vaccines and include:

  • Injection site reactions: pain, tenderness and swelling of the lymph nodes in the same arm as the injection, swelling and redness in the arm of the injection site
  • General side effects: fatigue, headache, muscle aches, joint pain, chills, nausea, vomiting and fever

There is a remote chance that the Pfizer/BioNTech and Moderna COVID-19 vaccines could cause a severe allergic reaction. A severe allergic reaction would usually occur within a few minutes to one hour after getting the injection. For this reason, we will ask you to wait at least 15 minutes (30 minutes if you have had a severe reaction to a vaccine in the past) before leaving the place where you received the injection. Signs of a severe reaction include:

  • Difficulty breathing
  • Swelling of your face and throat
  • A rapid heartbeat
  • A bad rash all over your body
  • Dizziness and weakness

All the possible reactions to the Pfizer/BioNTech and Moderna COVID-19 vaccines may not yet be known. These vaccines are still being studied in clinical trials.

What should I do if I experience side effects from the vaccine?

If you experience a severe allergic reaction, call 9-1-1 or go to the nearest hospital.

Otherwise, please contact One Medical if you have any side effects that bother you or do not go away.

You are encouraged to report vaccine side effects to the FDA/CDC Vaccine Adverse Event Reporting System (VAERS). The VAERS toll-free number is 1-800-822-7967 or you can report online.

We also recommend enrolling in V-Safe, a new voluntary smartphone-based tool that helps the CDC monitor the safety of COVID-19 vaccines. You will be given information on how to sign up at your vaccination appointment. For more information, please visit

Who should not get the COVID-19 vaccine?

You should not get a COVID-19 vaccine if you have had a severe allergic reaction after a previous dose of this vaccine OR a severe allergic reaction to any ingredient of the vaccine. We recommend speaking with your healthcare provider first to decide if a COVID-19 vaccine is right for you.



Messenger ribonucleic acid (mRNA)

Lipids (SM-102, polyethylene glycol [PEG]. 2000 dimyristoyl glycerol [DMG], cholesterol, and 1,2-dostearoyl-sn-glycero-3-phodphocholine [DSPC])


Tromethamine hydrochloride

Acetic acid

Sodium acetate



Messenger ribonucleic acid (mRNA)

Lipids (lipids ((4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate), 2 [(polyethylene glycol)-2000]-N,N-ditetradecylacetamide, 1,2-Distearoyl-sn-glycero-3- phosphocholine, and cholesterol)

Potassium chloride

Monobasic potassium phosphate

Sodium chloride

Dibasic sodium phosphate dihydrate, and sucrose.

I’ve had COVID-19 already. Should I still get a vaccine?

Yes. At this point, there is not enough evidence to know how long immunity from a COVID-19 infection lasts. It’s also unclear whether vaccination or infection produces the strongest immunity. However, if you had COVID-19 and were treated with monoclonal antibodies, you should wait 90 days before getting the vaccine.

Should I get the vaccine if I am pregnant, planning to become pregnant or breastfeeding?

We agree with the American College of Obstetrics and Gynecology in supporting anyone who is pregnant or breastfeeding to choose to get vaccinated if desired, especially if they are part of a high-risk group. Pregnancy testing is not needed prior to vaccination, and those who are trying to get pregnant do not need to postpone COVID-19 vaccination nor avoid pregnancy after getting vaccinated. If you have further questions about the COVID-19 vaccine and pregnancy or breastfeeding, please speak with your healthcare provider.

Should I get the vaccine if I am immunocompromised or on a medicine that affects my immune system?

Current COVID-19 vaccines may be administered to immunocompromised persons who do not have contraindications to vaccination. Please note there is a lack of data on vaccine safety and effectiveness in the immunocompromised population, as well as the potential for reduced immune response. Please continue to follow all current guidance to protect against COVID-19.

Should I get the vaccine if I am on blood thinning medication?

Those on blood thinning medication may safely be administered the COVID-19 vaccine. Please inform the person administering your vaccine that you are taking blood thinning medication so they ensure you get the best care.

How much will the vaccine cost?

The U.S. federal government has said it will cover the cost of vaccines for all Americans. According to Operation Warp Speed (OWS), a partnership between the U.S. Department of Health and Human Services, including the CDC, and the Department of Defense, the objective is to ensure that “no one desiring vaccination will face an economic barrier to receiving one.” In a report outlining its vaccine strategy, OWS said that various plans are in development to ensure that no American will be charged any out-of-pocket expenses for the vaccine, its distribution, or its administration.

What if I decide not to get the COVID-19 vaccine?

It’s completely up to you if you want to get vaccinated or not. Whether or not you decide to get vaccinated, please continue to protect yourself and others from the spread of COVID-19 through social distancing, wearing a mask in public, washing your hands frequently, etc.

When can I get my second dose?

After the first dose of the Pfizer/BioNTech vaccine, a second dose can be given as soon as 21 days. A 4-day early "grace period" is also allowed, which means it is acceptable to get the second dose as soon as 17 days after the first shot. For the Moderna vaccine, 28 days is recommended with 24 days being the earliest acceptable time. For both vaccines, the CDC has said up to 42 days is an acceptable window, so don’t worry if you get your shot longer than the 21 or 28 day period.

Keep your vaccination card

When you receive your first dose of the COVID-19 vaccine, you will get a vaccination card to show when you return for your next dose. Please remember to bring your card when you return for your second vaccination.

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