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COVID-19 Vaccine Frequently Asked Questions (FAQs)

Updated September 2, 2022

Some of the information below is provided by the Centers for Disease Control and Prevention (CDC), US Food and Drug Administration and the Missouri Department of Health and Senior Services (DHSS).

General COVID-19 Vaccine Questions

Why should I get the COVID-19 vaccine?

  • Helping to slow and stop the spread of COVID-19 is a team effort. You play a key part in keeping you and your family healthy.
  • Getting the COVID-19 vaccine adds one more layer of protection for you, your family, friends, coworkers and others.
  • Vaccines boost your immune system, so it will be ready to fight the virus if you are exposed.

How do I know the vaccine is safe?

All COVID-19 vaccines were tested in clinical trials involving tens of thousands of people to make sure they meet safety standards and protect people of different ages, races and ethnicities. This was a transparent, rigorous process.

Millions of Americans have received the Pfizer (Comirnaty), Moderna (Spikevax), Johnson & Johnson (Janssen) and Novavax vaccine, with the vast majority experiencing minor, temporary side effects. Medical and research professionals using public health data have reviewed final COVID-19 vaccine data.

The FDA has approved or authorized the following vaccines for use:

The CDC and FDA will keep monitoring the vaccines to look for safety issues. If an unexpected adverse event is seen in vaccinated individuals, experts quickly study it further to assess whether it is a true safety concern. Experts then decide whether changes are needed in US vaccine recommendations. This monitoring is critical to help ensure that the benefits continue to outweigh the risks for people who receive vaccines.

What is the cost of getting the COVID-19 vaccine?

No person can be billed for the COVID-19 vaccine itself. The vaccines are free from the federal government.

Vaccination providers may charge an administration fee to insurance, Medicaid or Medicare. The administration fee helps cover the cost of vaccination supplies and related expenses.

For those with insurance, this administration fee will be billed to their health plan. Individuals receiving the COVID-19 vaccine will not pay any out-of-pocket costs.

Missourians without health insurance will be able to receive the vaccination at no cost to them.

What are the ingredients in the COVID-19 vaccine?

COVID-19 vaccine ingredients are considered safe for most people. Nearly all of the ingredients in COVID-19 vaccines are ingredients found in many foods—fats, sugar and salts. The following is true for all four vaccines which are approved or authorized for emergency use by the FDA:

  • No preservatives like thimerosal or mercury or any other preservatives
  • No antibiotics like sulfonamide or any other antibiotics
  • No medicines or therapeutics like ivermectin or any other medications
  • No tissues like aborted fetal cells, gelatin or any materials from any animal
  • No food proteins like eggs or egg products, gluten, peanuts, tree nuts, nut products or any nut byproducts (COVID-19 vaccines are not manufactured in facilities that produce food products.)
  • No metals like iron, nickel, cobalt, titanium, rare earth alloys or any manufactured products like microelectronics, electrodes, carbon nanotubes or other nanostructures, or nanowire semiconductors.
  • No latex. The vial stoppers used to hold the vaccine also do not contain latex.

After the body produces an immune response, it discards all of the vaccine ingredients, just as it would discard any substance that cells no longer need. This process is a part of normal body functioning.

What can I expect when I get the COVID-19 vaccine?

Before Vaccination

  • See if a COVID-19 vaccine is recommended for you.
  • Learn about the different types of vaccines offered.

During Vaccination

  • You should receive a vaccination card or printout that tells you what COVID-19 vaccine you received, the date you received it, where you received it and when your next dose is due (if you get the Pfizer, Moderna or Novavax vaccines). The Janssen vaccine is a one-dose shot.
  • With the Pfizer, Moderna and Novavax COVID-19 vaccines, you will need two doses in order for the vaccine to be maximally effective. The second dose is usually given a few weeks after the first. Be sure to get the second dose on time -- even if you have side effects after the first one, unless a vaccination provider or your doctor tells you otherwise.

After Vaccination

  • Ask your healthcare provider about getting started with v-safe, a free, smartphone-based tool that uses text messaging and web surveys to provide personalized health check-ins after you receive a COVID-19 vaccination. V-safe also reminds you if you need an additional dose.
  • You may have some side effects, which are normal signs that your body is building protection in response to the vaccine. Side effects after a COVID-19 vaccination tend to be mild, temporary, and like those experienced after routine vaccinations. They can vary across different age groups.
    • Side effects for adults ages 18 and older may include the following:
      • Pain, swelling and/or redness at the vaccination site on the arm
      • Tiredness
      • Headache
      • Muscle pain
      • Chills
      • Fever
      • Nausea
    • Side effects for youth ages 4-17 may include the following (side effects are more common after the second dose):
      • Pain, swelling and/or redness at the vaccination site on the arm
      • Tiredness
      • Headache
      • Muscle or joint pain
      • Chills
      • Swollen lymph nodes
    • Side effects for youth ages 6 months to 3 years may include the following:
      • Pain at the vaccination site on the arm or leg
      • Swollen lymph nodes
      • Irritability or crying
      • Sleepiness
      • Loss of appetite
  • Consult your healthcare provider if you have any of the following symptoms after getting the vaccine:
    • Redness or tenderness at the vaccination site that gets worse after 24 hours
    • Side effects are worrying or don't seem to go away after a few days

Do I still need to wear a mask and avoid close contact with others after I am vaccinated?

Generally, if you are up to date on your COVID-19 vaccinations (received all doses in a primary series and all boosters recommended for you, when eligible), you do not need to wear a mask in outdoor settings.

Check your local COVID-19 community level for recommendations on when to wear a mask indoors and additional precautions you can take to protect yourself from COVID-19.

If you are immunocompromised or more likely to get very sick from COVID-19, learn more about how to protect yourself.

How long does protection from a COVID-19 vaccine last?

Scientists are monitoring how long COVID-19 vaccine protection lasts. COVID-19 vaccines work well to prevent severe illness, hospitalization and death.

However, public health experts are seeing decreases in the protection COVID-19 vaccines provide over time, especially for certain groups of people. Due to this, the CDC recommends COVID-19 vaccines for everyone ages 6 months and older, and boosters for everyone 5 years and older, if eligible. 

Can I get the COVID-19 vaccine and other vaccines at the same time?

You can get a COVID-19 vaccine and other vaccines, including a flu vaccine, at the same visit. Experience with other vaccines has shown that the way our bodies develop protection, known as an immune response, after getting vaccinated and possible side effects of vaccines are generally the same when given alone or with other vaccines. Learn more about the timing of other vaccines.

COVID-19 Vaccine Eligibility

Who is eligible to get the vaccine?

The CDC recommends COVID-19 vaccines for everyone ages 6 months and older and boosters for everyone 5 years and older, if eligible. 

Should pregnant women get the COVID-19 vaccine?

COVID-19 vaccination is recommended for all people 6 months and older, including people who are pregnant, breastfeeding, trying to get pregnant now or might become pregnant in the future.

Evidence about the safety and effectiveness of COVID-19 vaccination during pregnancy has been growing. There is currently no evidence that any vaccines, including COVID-19 vaccines, cause fertility problems in women or men.

Pregnant and recently pregnant people are more likely to get severely ill with COVID-19 compared to people who are not pregnant.

Should cancer patients get the COVID-19 vaccine?

The American Cancer Society (ACS) and the National Comprehensive Cancer Network (NCCN) both recommend that all people with cancer should be fully vaccinated as soon as they can with the COVID-19 primary vaccine series, plus additional booster doses. This includes people who have already had COVID-19. Learn more about COVID-19 vaccines in people with cancer.

Addressing Myths

Does the vaccine alter my DNA?

No. The COVID-19 vaccine does not affect or interact with your DNA in any way. mRNA vaccines never enter the nucleus of the cell, which is where our DNA is stored. The cell breaks down and gets rid of the mRNA soon after it is finished using the instructions provided by the vaccine.

Information on mRNA vaccines provided by the Centers for Disease Control and Prevention (CDC). Learn more about mRNA COVID-19 vaccines.

Can I get COVID-19 from the vaccine?

No. None of the COVID-19 vaccines currently approved or authorized for emergency use in the United States use the live virus that causes COVID-19. 

If I already had COVID-19, do I need to be vaccinated?

Yes. Getting a COVID-19 vaccine gives most people a high level of protection against COVID-19 and can provide added protection for people who already had COVID-19. One study showed that, for people who already had COVID-19, those who do not get vaccinated after their recovery are more than two times as likely to get COVID-19 again than those who get fully vaccinated after their recovery.

Experts are still learning more about how long vaccines protect against COVID-19. 

COVID-19 Vaccine Boosters

What is a booster shot, and how does it work?

Booster doses serve as a reminder to your immune system, ultimately providing reinforcements for your body to recognize and ward off COVID-19 as the initial effectiveness of each of the three approved vaccines wane over time. The effectiveness of the Moderna, Pfizer and Johnson & Johnson vaccines against severe infection remain incredibly high, but receiving a booster shot will help your immune system prevent mild to moderate infection, ultimately making you and your family safer.

Which vaccines have booster shots?

Three FDA authorized COVID-19 vaccines (Pfizer, Moderna and Johnson & Johnson) are approved for booster shots. The Novavax COVID-19 vaccine is not authorized for a booster dose at this time.

    Do I need a booster dose of the COVID-19 vaccine?

    The CDC recommends COVID-19 booster doses for the following individuals:

    • Pfizer:
      • First booster: for age 5 and older (at least 5 months after your second shot of a primary series)
      • Second booster: for age 50 and older (at least four months after your first booster dose)
    • Moderna: 
      • First booster: for ages 18 and older (at least five months after your second shot of a primary series)
      • Second booster: for age 50 and older (at least four months after first booster dose).
    • Johnson & Johnson (Janssen): 
      • First booster: for ages 18 and older (at least two months after your primary dose)
      • Second booster: Anyone who received a Johnson & Johnson vaccine for both their primary dose and booster can get a second booster (at least four months after the first booster). Adults 50 years and older who first received a Johnson & Johnson vaccine, regardless of what type of booster they received, also should get a second booster (at least four months after the first booster). The second booster must be an mRNA booster (such as Pfizer or Moderna).

    The Pfizer-BioNTech or Moderna COVID-19 vaccines (mRNA vaccines) are preferred in most situations for booster doses. You may get the Janssen vaccine in some situations. Children ages 5-17 may only get a Pfizer-BioNTech COVID-19 vaccine booster.

    What are booster recommendations for immunocompromised individuals?

    If you are moderately or severely immunocompromised (have a weakened immune system), you are at increased risk of severe COVID-19 illness and death. Additionally, your immune response to COVID-19 vaccination may not be as strong as in people who are not immunocompromised. Learn more about COVID-19 vaccines for people who are moderately or severely immunocompromised.

    Can I get a COVID-19 booster for the omicron variant?

    The CDC recommends the use of updated COVID-19 boosters from Pfizer-BioNTech for people ages 12 years and older and from Moderna for people ages 18 years and older. Updated COVID-19 boosters add Omicron BA.4 and BA.5 spike protein components to the current vaccine composition, helping to restore protection that has waned since previous vaccination by targeting variants that are more transmissible and immune-evading.

    How long do I need to wait to get a COVID-19 primary shot or booster after having COVID-19?

    If you recently had COVID-19, you may consider delaying your next vaccine dose (primary dose or booster) by 3 months from when your symptoms started or, if you had no symptoms, when you first received a positive test. Reinfection is less likely in the weeks to months after infection.

    However, certain factors, such as personal risk of severe disease, local COVID-19 community level, and the most common COVID-19 variant currently causing illness, could be reasons to get a vaccine sooner rather than later.

    People who have COVID-19 and are in isolation, should wait to get vaccinated until symptoms are gone (if you had symptoms) and criteria to discontinue isolation have been met.

    Children and adults who have (or have recently had) multisystem inflammatory syndrome (MIS), should wait to get vaccinated until recovering from being sick and it has been 90 days since the date of diagnosis of MIS-A or MIS-C.

    What side effects are reported after getting a COVID-19 booster shot?

    The most common side effects after a booster shot are fever, headache, fatigue (tiredness) and pain at the injection site. Most side effects were mild to moderate. Learn more about possible side effects after COVID-19 shots.

    COVID-19 Vaccines and Children

    Why should I consider vaccination for my child?

    Pediatricians, infectious disease doctors and other experts overwhelmingly recommend COVID-19 vaccination in most cases. The CDC recommends COVID-19 vaccines for everyone ages 6 months and older and boosters for everyone 5 years and older, if eligible. 

    With many children back in school and participating in extracurricular activities, COVID-19 vaccination among children as young as age 6 months is critical to preventing infection and possible severe disease, as well as reducing the spread of COVID-19. While fewer children have been sick with COVID-19 compared to adults, children can be infected with the virus, and there is no way to tell in advance if a child will get a severe or mild case. After a natural infection, some children have developed a rare but serious disease that is linked to COVID-19 called multisystem inflammatory syndrome (MIS-C).

    As more variants of COVID-19 develop, vaccination continues to be our best tool to reduce the chances that the virus has to mutate.

    Choosing vaccination will:

    • Protect your child from severe illness and disease
    • Maintain in-person school, sports and extracurricular activities
    • Protect your family members by reducing transmission
    • Protect our communities from future variant development

    What side effects from the COVID-19 vaccine have been observed in children?

    Side effects after a COVID-19 vaccination tend to be mild, temporary and like those experienced after routine vaccinations. These are normal signs that their body is building protection, but they should go away in a few days.

    Side effects for youth ages 4-17 may include the following (side effects are more common after the second dose):

    • Pain, swelling and/or redness at the vaccination site on the arm
    • Tiredness
    • Headache
    • Muscle or joint pain
    • Chills
    • Swollen lymph nodes

    Side effects for youth ages 6 months to 3 years may include the following:

    • Pain at the vaccination site on the arm or leg
    • Swollen lymph nodes
    • Irritability or crying
    • Sleepiness
    • Loss of appetite

    What should a parent do if a child transitions from a younger age group to an older age group between their first dose and second dose?

    The CDC recommends vaccine recipients receive the recommended age-appropriate vaccine product and dosage based on their age on the day of vaccination. If a person moves from a younger age group to an older age group during the primary series or between the primary series and receipt of the booster dose(s), they should receive the vaccine product and dosage for the older age group for all subsequent doses.

    Learn more about the Pfizer-BioNTech vaccine for children who transition from a younger to an older age group.

    Learn more about the Moderna vaccine for children who transition from a younger to an older age group.

    Is Phelps Health offering COVID-19 vaccines for children?

    Yes, Phelps Health is offering the Pfizer COVID-19 vaccine for children ages 5 through 18 and the Moderna COVID-19 vaccine to kids ages 6 months to 4 years old in the Pediatrics Clinic in the Medical Office Building in Rolla. Please call (573) 426-3225 to schedule a COVID-19 vaccine for your child(ren). A parent or guardian must sign the consent form at https://bit.ly/3ixjNoX and be present with their teen when the child is vaccinated.

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