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Q: How do COVID-19 vaccines work? 

A: The first COVID-19 vaccines to reach the market are messenger RNA, or mRNA, vaccines. Messenger RNA vaccines work by instructing cells in the body how to make a protein that triggers an immune response.  The mRNA is NOT a live or attenuated live virus so it cannot make you sick with COVID-19.  Injecting messenger RNA into your body will not interact or do anything to the DNA of your cells. Human cells break down and get rid of the messenger RNA soon after they have finished using the instructions.

Q:  Are COVID-19 vaccines safe? 

A:  Red tape may have been cut, but no corners were cut.  Safety protocols were still followed and adequate testing was still completed.  The emergency situation of the worldwide pandemic warranted an emergency response. 

The vaccines developed by Pfizer/BioNTecH and Moderna have been studied in approximately 70,000 people.  To receive emergency use authorization, biopharmaceutical manufacturers must have followed at least half of the participants in their vaccine trials for at least two months after completing the vaccination series, and the vaccine must be proven safe and effective in that population.  The safety of COVID-19 vaccine will continue to be closely monitored by the CDC and the FDA as we start vaccinating and continue with more trials.

Q: If I already had COVID-19 and I have recovered, do I still need to get vaccinated for COVID-19?

A: Natural immunity develops after an actual infection and can protect someone from getting that infection again.  Early evidence suggests natural immunity from COVID-19 may not last long, but more studies are needed to better understand this.  It is recommended to get the COVID-19 vaccine even if you've had COVID-19 previously. However, those who have had COVID-19 should delay vaccination until about 90 days from diagnosis. 

Q: Do the mRNA COVID-19 vaccines have severe side effects?

A: COVID-19 vaccines have been shown to have short-term mild or moderate vaccine reactions that resolve without complication or injury.

Early-phase studies of the Pfizer/BioNTech and Moderna vaccines show that they are safe. The most common symptoms included pain at the injection site, headache, chills, fatigue, muscle pain or fever lasting for a day or two.

Keep in mind that these side effects indicate that your immune system is responding to the vaccine. These side effects are common with all vaccinations.

Q: Are there any concerns with those with a history of severe allergic reactions?

A:  If you have ever had a severe allergic reaction to any ingredient in a COVID-19 vaccine, the CDC recommends that you should not get that specific vaccine. If you have had a severe allergic reaction to other vaccines or injectable therapies, you should ask your doctor if you should get a COVID-19 vaccine. Your doctor will help you decide if it is safe for you to get vaccinated.  Specifically, those with KNOWN allergic reaction to PEG (polyethylene glycol) or polysorbate should not get an mRNA COVID-19 vaccine.  (Polysorbate is not in the vaccine, but is closely related to PEG).

The CDC recommends that people with a history of severe allergic reactions not related to vaccines or injectable medications—such as allergies to food, pet, venom, environmental, or latex—may still get vaccinated. People with a history of allergies to oral medications or a family history of severe allergic reactions, or who might have an milder allergy to vaccines (no anaphylaxis)—may also still get vaccinated.

If you have a severe allergic reaction after getting the first shot, you should not get the second shot. Your doctor may refer you to a specialist in allergies and immunology to provide more care or advice.

Q: Should the COVID-19 vaccine be given with other vaccines?

A:  The current recommendation is to avoid giving other vaccines on the same day as any COVID-19 vaccine AND to avoid any other vaccine within 2 weeks of the COVID-19 vaccine.  Of note, PPD (purified protein derivative) or TST (tuberculin skin test) CAN be given on the same day as the COVID-19 vaccine or it must be give 4 weeks AFTER a COVID-19 vaccine. TB testing via bloodwork (quantiferon gold) should be done before COVID-19 vaccine or 4 weeks after COVID-19 vaccine.

Q: If I am breastfeeding, can I get an mRNA COVID-19 vaccine?

A:  There is no data on the safety of COVID-19 vaccines in lactating women or on the effects of mRNA vaccines on the breastfed infant or on milk production/excretion. mRNA vaccines are NOT thought to be a risk to the breastfeeding infant. The American College of Obstetricians and Gynecologists, Society of Fetal Maternal Medicine, and the Academy of Breastfeeding Medicine all state that the benefits of vaccination outweigh the theoretical small safety concerns.  There is no need to avoid initiation or discontinue breastfeeding in patients who receive the COVID-19 vaccine.

Q: Once I have been vaccinated, am I exempt from mask wearing, social distancing, etc?

A: It may take time for everyone who wants a COVID-19 vaccination to get one. Also, while the vaccine may prevent you from getting sick, it is unknown whether you can still carry and transmit the virus to others after vaccination.

Until more is understood about how well the vaccine works, continuing with precautions (such as wearing a mask, practicing physical distancing, washing hands frequently and avoiding crowds) will be important.

Q:  Will CAP offer the vaccine to patients, if so what ages? 

A:  At this time, the approval for the Pfizer vaccine is age 16 years and up.  The approval for the Moderna vaccine is age 18 years and up.  Trials are currently enrolling younger ages for both companies, down to age 12 years.  We will closely be following the CDC recommendations for the allocation of COVID vaccine. At this time, we cannot yet say whether we will get a supply in the near future.  We will continue to follow the data and hope that it shows safety and efficacy for children of all ages.

Q: When might the vaccine be available to children under 16?

A:  We don’t know yet as trials are still being completed for children ages 12 years and up.  We hope that they will also be able to begin trials for younger children at some point. Our best guess for most children is Fall 2021 at the earliest.  This would be based on information regarding safety and efficacy, as well as the logistics of supply and distribution.  

Q: What is going on in our area for COVID vaccine administration to the public?

A:  On April 18, 2021, ALL Virginians age 16 years old and up will be eligible to receive the COVID vaccine.  Individuals in the Fairfax Health District will be eligible to directly schedule a vaccine appointment through as Fairfax County moves into Phase 2 with the rest of Virginia.  With this new system, Fairfax County will no longer accept registrations for the COVID vaccine.  More info here.  Other Virginians are encouraged to continue using Vaccinate VA.

This is a complex process, requiring vaccine supply, staff to administer vaccine, and staff and space to allow for social distancing and safety monitoring after vaccine administration. 

State of Virginia
Fairfax County
District of Columbia