Coronavirus Vaccine FAQs

There are currently two COVID-19 vaccines available in the United States — one created by Pfizer and its partner BioNTech, and the other created by Moderna. The Pfizer vaccine can be administered to people aged 16 years and older, while the Moderna vaccine is for use in people aged 18 years and older.

As of January 1, 2021, three COVID-19 vaccines were in phase 3 clinical trials in the United States. They were created by the following companies:

• Oxford-AstraZeneca
• Johnson & Johnson
• Novavax

Pfizer and Moderna's vaccines do not contain the COVID-19 virus. Instead, they work by using an mRNA molecule that instructs your cells to make copies of a harmless protein that is on the outer shell of the COVID-19 virus. When your immune system detects this protein, it begins to produce antibodies as if the body has been infected. The antibodies will help your immune system fight off future COVID-19 infections. 

It is unknown how long a COVID-19 vaccine will protect you. Pfizer and Moderna will follow their clinical trial participants for at least a year and will be able to provide information about lasting protection in the future.

Pfizer and Moderna have reported no serious safety concerns from their vaccines. All the participants in their clinical trials have been followed for at least two months after getting vaccinated to look for side effects and will continue to be followed for 1-2 years. Some participants have reported sore arms, fatigue, fever and joint and muscle aches that last for a day or two. It is important to know that if you experience any of these reactions, it’s normal and means the vaccine is working.

There is currently no data on the safety and effectiveness of the Pfizer and Moderna vaccines for pregnant or breastfeeding women.

Because vaccine supply is limited, the Centers for Disease Control (CDC) is currently recommending to federal, state and local governments that vaccines be distributed in phases:

• Phase 1a: Health care personnel and residents of long-term care facilities.
• Phase 1b: Frontline essential workers and people aged 75 years and older.
• Phase 1c:
  • People aged 65-74 years.
  • People aged 16-64 years with underlying medical conditions which increase the risk of serious, life-threatening complications from COVID-19.
  • Other essential workers, such as people who work in transportation and logistics, food service, housing construction and finance, information technology, communications, energy, law, media, public safety and public health.

As the availability of the vaccines increase, the CDC will expand its recommendations to include more groups.

Because children’s bodies are so different from adult bodies, it’s important to thoroughly test the COVID-19 vaccines on them as well. Children’s immune systems respond differently so we won’t know the safety and efficacy of an adult vaccine until we do trials in children.

The American Academy of Pediatrics (AAP) is urging federal agencies to support timely, but safe, development of COVID-19 vaccines for children, to help understand any potential unique immune responses and/or safety concerns in children. 

You can expect initial testing to occur in teenagers and once the safety of a vaccine is established in older children, testing will move to younger age groups. Much like the trials performed in adults, these will take months and the data will have to be analyzed.

As of January 1, 2021, Pfizer and Moderna were conducting phase 3 clinical trials on their vaccines with children as young as 12 years old.

MIS-C, or Multisystem Inflammatory Syndrome in Children, is a condition in which different body parts become inflamed, such as the heart, lungs, kidneys, brain, gastrointestinal tract, skin or eyes. One of the reasons clinical trials are important is to make sure that the vaccines do not have any side effects, such as causing MIS-C. While the vaccines have yet to be tested in children, adult clinical trials have not resulted in any cases of MIS-A (Multisystem Inflammatory Syndrome in Adults). In fact, it is possible that by protecting against COVID-19, a vaccine will also protect against MIS-C.

Vaccine availability and distribution varies from state to state. For the most current information on vaccine distribution, contact your local health department:

• DC Department of Health
• Maryland Department of Health
• Virginia Department of Health

If you have already had COVID-19, you can still benefit from being vaccinated. A vaccine will add to your immunity to the virus and protect you from getting the virus again. 

No. You should not stop wearing a mask, especially since coronavirus infection levels are currently rising all over the world. Even when the vaccines become widely available, many experts say that safety measures like social distancing, handwashing and mask wearing will still be necessary until the threat has subsided.