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Covid-19 Vaccine (1 Dose)

Medically reviewed by Last updated on Oct 31, 2022.

What do I need to know about the COVID-19 1-dose vaccine?

The COVID-19 1-dose vaccine is given to help prevent severe illness. The vaccine does not contain the virus that causes COVID-19. This means you are not at risk for getting COVID-19 from the vaccine. Instead, the vaccine teaches your immune system to recognize the virus and produce antibodies to fight it. Healthcare providers recommend a COVID-19 vaccine, even if you have already had COVID-19.

What do I need to know about official approval for this vaccine?

This vaccine has emergency use authorization (EUA) for adults 18 years or older. An EUA means it is not officially approved but is being given because the benefits outweigh the risks. This vaccine may be given if you cannot get a 2-dose COVID-19 vaccine.

How is the vaccine given?

The vaccine is given as a shot into a muscle in your shoulder area. Your provider will monitor you for about 15 minutes after the shot is given.

What do I need to know about booster shots?

  • A booster shot is an additional dose of vaccine. A booster helps your immune system continue to protect against severe COVID-19. A booster is recommended for all adults who received this vaccine. The booster should be a 2-dose brand of COVID-19 vaccine, if possible.
  • You may need a second booster. A second booster is recommended for all adults 50 or older and all adults who are immunocompromised. You should also get a second booster if you received the 1-dose COVID-19 vaccine as the original dose and as a booster.
  • Your healthcare provider can help you schedule boosters. The timing depends on your age, if you are immunocompromised, and the number of doses of this vaccine you received.

What are reasons I should wait to get the COVID-19 vaccine?

  • You are sick or have a fever.
  • You had COVID-19 and received monoclonal antibodies or convalescent plasma. Wait at least 90 days after the end of treatment to get the vaccine.

What do I need to tell my healthcare provider before I get the vaccine?

  • You received a dose of a different COVID-19 vaccine. Your provider may recommend you get a second dose of the other vaccine instead to complete a 2-dose schedule.
  • You have an allergy to any component (part) of the vaccine.
  • You have a history of allergies.
  • You have a bleeding disorder or take blood thinning medicine.
  • Your immune system is weakened from a medical condition or from medicines such as chemotherapy or steroids.
  • You know or think you are pregnant. Talk to your obstetrician or doctor about the benefits and risks of the vaccine during pregnancy.
  • You are breastfeeding.

What happens after I get the vaccine?

You will be considered fully vaccinated 2 weeks after you get the vaccine. This is how long your immune system needs to build a response strong enough to protect you. The following are guidelines to follow when you are fully vaccinated :

  • Continue being careful until experts are sure a fully vaccinated person cannot get infected or pass the virus to others. Wear a face covering and stay 6 feet away from others when you are in public. Remember to wash your hands often.
  • It is considered safe to gather indoors without face coverings or social distancing if everyone there is fully vaccinated.
  • If you are exposed to the virus, you do not need to isolate or get tested unless you develop symptoms.
  • Check to see if you need to be tested before you travel. You may also need to quarantine after you return. Some countries require proof of a negative test before you leave. You should also be tested 3 to 5 days after you return from another country.
  • You may need to wear a face covering (mask) while you travel by plane, bus, or train.

What are the risks of the vaccine?

This is a new vaccine. All side effects may not be known. The following are possible side effects:

  • You may develop blood clots or thrombocytopenia syndrome (a low blood platelet count).
  • You may have an allergic reaction to the vaccine. The vaccine can cause a life-threatening allergic reaction called anaphylaxis. This is rare.
  • The vaccine may cause mild symptoms, such as a fever, chills, headache, and muscle aches. You may also be tired, have nausea, or develop a fever.
  • The area where you got the shot may be swollen, sore, red, or tender. This is usually mild and goes away in a few hours. It may help to move your arm around.
  • The vaccine may not be as helpful if your immune system is weak.
  • You may still get infected with the coronavirus after you receive the vaccine.

What else can I do to prevent coronavirus infection?

Droplets are the most common way all coronaviruses spread. The virus spreads from person to person through talking, singing, coughing, and sneezing. Continue to do the following to keep yourself and others safe, even if you have had the vaccine:

  • Wash your hands often throughout the day. Use hand sanitizer that contains alcohol if soap and water are not available. Do not touch your eyes, nose, or mouth without washing your hands first. Teach children how to wash their hands and use hand sanitizer.
  • A face covering is recommended when you are in public, such as grocery stores, pharmacies, and on mass transit. You may live in an area that has a face covering mandate. This means you must wear a covering in public. Check the laws in your area before you leave your home. Bring extra coverings with you.
    How to Wear a Face Covering (Mask)
Prevent COVID-19 Infection

What else do I need to know about the vaccine?

  • A vaccinated person will not automatically test positive for COVID-19. It is possible to become infected 2 weeks after your last dose. You may also be able to pass the virus to others without knowing you are infected. Be sure to continue following social distancing guidelines in your area.
  • The vaccine does not cause reproductive problems. Your healthcare provider can give you more information about the safety of vaccines before or during pregnancy. The vaccine is not believed to cause fertility problems.
  • Your DNA will not be changed. The vaccine does not affect the part of cells that control DNA.
  • Your child may need to be fully vaccinated to attend school. Ask your child's school as soon as possible. Vaccine requirements may vary by state or other local area.
  • Let your healthcare provider know when you have received the vaccine. Make a copy of your vaccination card. Keep the original with you in case you need to show it. Keep the copy in a safe place.

Call your local emergency number (911 in the US) if:

  • You have signs of a severe allergic reaction, such as trouble breathing, hives, or wheezing.
  • Your mouth and throat are swollen.
  • You have chest pain or your heart is beating faster than normal for you.
  • Your face is red or swollen.
  • You have hives that spread over your body.

When should I call my doctor or the place where I got the vaccine?

  • You have a fever.
  • You have any other signs or symptoms that concern you or do not go away.
  • You have increased pain, redness, or swelling around the area where the shot was given.
  • You have questions or concerns about the COVID-19 vaccine.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your healthcare providers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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