Skip to main content
Dartmouth-Hitchcock logo
Summer Flowers In This Section

Vaccine FAQ

In addition to the general questions and answers below, specific FAQ are available for specific groups of patients:

When will the COVID-19 vaccine be available?

Currently, only the Pfizer-BioNTech and Moderna COVID-19 vaccines are available for use under the Emergency Use Authorization (EUA) from the FDA. 

Other manufacturer vaccines, such as AstraZeneca, Janssen, Novavax and Sanofi/GSK are in various stages of development, but only the Pfizer-BioNTech and Moderna vaccines are currently available for use. Expected delivery dates, as well as numbers of doses to be delivered, are changing on a daily basis. Dartmouth-Hitchcock Health (D-HH) is working closely with the New Hampshire and Vermont public health officials on plans to distribute the vaccine as it becomes available. We are committed to updating you about availability as information is confirmed.

Who will receive the COVID-19 vaccine?

Initial vaccine supply will be limited so not everyone will be able to be vaccinated right away. The COVID-19 vaccine will be given first to people at highest risk of infection including health care personnel and residents of long-term care facilities. Prioritization guidelines are in development for workers in essential and critical industries, people at high risk for severe COVID-19 illness due to underlying medical conditions, and people 65 years and older.

Herd immunity, or community immunity, occurs when 70%of the community is immune to a disease through vaccination and/or prior illness. Community immunity makes the spread of the virus from person to person unlikely. 

How is the vaccination given?

COVID-19 mRNA vaccines (such as the Pfizer-BioNTech and Moderna vaccines) are given in two doses, injected into the muscles of the upper arm, similar to a flu shot (intramuscularly).

Why do I have to receive two doses of the vaccine?

The first shot starts building immunity, but it is not enough for protection. The second shot given a few weeks later is needed to get the most protection from the vaccine.

When is the second vaccine dose given?

Pfizer-BioNTech's vaccine is a 2-dose intramuscular injection separated by 21 days.

Moderna’s vaccine is a 2-dose intramuscular injection separated by 28 days (1 month)

Does the second dose of the vaccine have to be the same vaccine I was initially given?

Yes. The COVID-19 vaccine products are not interchangeable; the second dose must be from the same manufacturer as your first dose.

When you receive your first dose, you will also receive a COVID-19 vaccination record card. Bring your COVID-19 vaccination record card when you return for your second dose to ensure you are getting the appropriate vaccination. You should be sure to return to the same location where you received your first dose.

Is the vaccine safe?

The data from clinical trials indicate that the Pfizer-BioNTech and Moderna vaccines are safe. Both vaccines have undergone extensive clinical trials that tested for safety and efficacy before being submitted to the FDA for Emergency Use Authorization. To learn more about each vaccine, please reference the vaccine fact sheets:

What are the common side effects?

Please reference the Moderna and Pfizer-BioNTech vaccine fact sheets for the most up-to-date information about side effects:

What if I have a reaction, side effect, or an adverse event?

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

If you believe you are having an adverse reaction, you should contact your health care provider and seek medical attention immediately. Adverse events following vaccination should be reported through the Vaccine Adverse Event Reporting System (VAERS) (1-800-822-7967 or through their website). Please note: Dartmouth-Hitchcock employees should follow guidance outlined in the employee frequently asked questions found on the employee intranet.

The CDC is implementing a new smartphone-based tool called v-safe to check-in with people about side effects after they receive a COVID-19 vaccine. When you receive your vaccine, you should also receive a v-safe information sheet telling you how to enroll in v-safe. If you enroll, you will receive regular text messages directing you to surveys where you can report any problems or adverse reactions you have after receiving a COVID-19 vaccine. 

Is the vaccine a live vaccine?

No, the vaccine does not contain any live virus.

Can I choose which vaccine I receive?

Due to the current limited supply of vaccine, you will not be able to choose a specific vaccine manufacturer at this time.

If I've already had COVID-19, do I still need the vaccine?

The CDC states that it cannot comment on whether people who had COVID-19 should get a COVID-19 vaccine. There is not enough information currently available to say if, or for how long, after infection someone is protected from getting COVID-19 again.

Can I receive the COVID-19 vaccine if I am pregnant or breastfeeding?

As pregnant women were not included in the vaccine clinical trials, there is not enough data to know if the vaccine is safe for pregnant or lactating women. We recommend that you reference the vaccine fact sheets and recommendations from the American College of Obstetricians and Gynecologists (ACOG) listed below. Pregnant and lactating women should also contact their health care provider to discuss the current information available and each women's individual circumstance before making a decision about receiving the vaccination.

Can I receive the COVID-19 vaccine if I have had a severe allergic reaction to another vaccine?

If you have had a severe allergic reaction after a previous dose of this vaccine, or if you have had a severe allergic reaction to any ingredient in the vaccine, the Emergency Use Authorization Fact Sheet states that you should not get the Pfizer-BioNTech or Moderna COVID-19 vaccine. We recommend that individuals with a history of anaphylaxis (severe, potentially life-threatening allergic reaction) consult their health care provider on making the decision as to whether or not to be vaccinated.

Can I receive the COVID-19 vaccine on the same day as my flu shot?

The COVID-19 vaccine should be given alone and at least 14 days after you received another vaccine(s). This is to limit any potential interaction between the two vaccines that may interfere with the vaccine's effectiveness.

Flu vaccination is encouraged for people who have not already received their annual flu vaccine. The flu vaccination is critical to reduce instances of flu in your community. Reducing flu cases also reduces the number of people seeking care for respiratory illness. This effort directly helps reduce the strain on the health care system during COVID-19 pandemic. Timing of flu vaccine and COVID-19 vaccine should be discussed with your primary care provider.

I just received an unrelated vaccine. When should I receive my COVID-19 vaccine?

The COVID-19 vaccine should be given alone and at least 14 days after you received another vaccine (such as a flu vaccination or varicella-zoster). This limits any potential interaction between the two vaccines that may interfere with the vaccine's effectiveness.

I was recently diagnosed with COVID-19. When should I receive my COVID-19 vaccine?

Vaccination should be deferred for patients with suspected or confirmed COVID-19, regardless of whether they have symptoms, until they have met the criteria to discontinue their isolation.

I was treated for COVID-19 with antibody therapy. When should I receive my COVID-19 vaccine?

The COVID-19 vaccine should not be given for at least 90 days after a person receives passive antibody therapy (such as convalescent plasma and/or monoclonal antibodies, such as bamlanivimab and casirivimab/imdevimab) for the treatment of COVID-19, to avoid the possibility of the antibody therapy interfering with the vaccine.

Do I need to continue wearing my mask after I receive the vaccine?

Yes. While experts learn more about the protection that COVID-19 vaccines provide under real-life conditions, it is important for everyone to continue covering your mouth and nose with a mask, washing hands often, and staying at least 6 feet away from others.

Together, COVID-19 vaccination and following the CDC's recommendations for how to protect yourself and others will offer the best protection from getting and spreading COVID-19.

How effective is the vaccine, and when does the vaccine protection begin?

Based on manufacturer data, Pfizer-BioNTech’s vaccine was found to be 94.6% effective against COVID-19 beginning 7 days after the second dose. Moderna's vaccine was found to be 94.1% effective against COVID-19 after receiving two doses and 100% effective against severe COVID-19 disease. Additional information about effectiveness can be found on the vaccine fact sheets:

Could I test positive for  COVID-19 after receiving the vaccine?

No, not as a result of the vaccine alone. The vaccines won’t cause you to test positive on viral tests. If your body develops an immune response, which is the goal of vaccination, there is a possibility you may test positive on some antibody tests.

Will there be a test for immunity as a result of the vaccine?

No. The antibody tests currently in use will generally only detect the type of antibody that is produced by a natural infection, not antibodies produced by a response to vaccination. Experts are currently looking at how COVID-19 vaccination may affect antibody testing results.

Where can I get more information?

We understand that there are many questions and we encourage you to consult the following websites for additional information:

D-HH Associate Chief Quality Officer Michael S. Calderwood, MD, MPH addresses questions you may have in this video.

Is information about the vaccine available in languages other than English?

The FDA website includes Pfizer-BioNTech fact sheets in several languages other than English.