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FAQ: COVID-19 Vaccines

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What vaccines are currently available?

Currently, three vaccines are authorized and recommended in the United States to prevent COVID-19: Pfizer-BioNTech, Moderna, and Johnson & Johnson. Pfizer-BioNTech and Moderna are mRNA vaccines. Johnson & Johnson is a viral vector vaccine. Other information:

  • Pfizer-BioNTech: For use in people age 12 and older; two shots given at least 21 days apart
  • Moderna: For use in people age 18 and older; two shots given at least 28 days apart
  • Johnson & Johnson: For use in people age 18 and older; one shot

On August 23, 2021, the U.S. Food and Drug Administration (FDA) gave its full approval to the Pfizer-BioNTech COVID-19 vaccine. Full FDA approval means that the vaccine now has the same level of FDA approval as all other approved vaccines and drugs. The Moderna and Johnson & Johnson vaccines are approved by the FDA under Emergency Use Authorization (EUA) and are expected to apply for full approval in the coming months.

Does the vaccine cover the new coronavirus variants?

According to the CDC, studies conducted thus far suggest that antibodies generated through vaccination with currently authorized vaccines Are effective against these variants. This is being closely investigated and more studies are underway. Scientists are working to learn more about these variants, and more studies are needed to understand how these variants may affect existing therapies, vaccines, and tests.

Do I need a booster shot?

Federal health officials and medical experts have joint released statement announcing a plan to provide booster doses to all individuals eight months after they have received their second mRNA vaccine. We are actively reviewing this guidance to form a delivery plan for our caregivers and patients. This plan is still being reviewed by the FDA and CDC and we will continue to follow the guidance after they review and release recommendations. We will share more information as soon as we know more.

In the meantime, the Centers for Disease Control and Prevention (the CDC) currently recommends that some people receive a third dose of the COVID 19 vaccine now. This includes people who:

  • Are receiving active cancer treatment
  • Have received an organ transplant and are taking medicine to suppress the immune system
  • Have received a stem cell transplant within the last two years or are taking medicine to suppress the immune system
  • Have advanced or untreated HIV infection
  • Have active treatment with high-dose corticosteroids or other drugs that may suppress your immune response (e.g., prednisone, tacrolimus, mycophenolate, azathioprine, Humira, Enbrel, Remicade, etc.)
  • Have moderate or severe primary immunodeficiency (such as DiGeorge syndrome or Wiskott-Aldrich syndrome)

Can I mix and match the vaccines?

For people who received either Pfizer-BioNTech or Moderna's COVID-19 vaccine series, a third dose of the same mRNA vaccine should be used. A person should not receive more than three mRNA vaccine doses. If the mRNA vaccine product given for the first two doses is not available or is unknown, either mRNA COVID-19 vaccine product may be administered.

What should immunocompromised people who received the J&J/Janssen vaccine do?

The current recommendations do not apply to J&J/Janssen Vaccine. Currently it is not recommended that anyone who received this vaccine receives an additional shot.

What should I do next?

If you clearly meet one of these criteria, you can visit the state's vaccine finder website to find a retail pharmacy or other location to get a booster injection. Your healthcare provider does not need to order the booster shot. If you have further questions regarding your eligibility, you can read the CDC updated recommendations, or you can contact your provider.

If I am not immunocompromised, should I get a booster shot?

There are additional discussions around providing booster vaccination to all patients after 8 months from the second shot they received. UMass Memorial Health will provide more information about this as soon as it is available.

Were the vaccines rushed through production?

This is a very common concern since the vaccine was developed, tested and approved rather quickly. The same process had been developed and tested for other viral illnesses, years before COVID-19. The same rigorous standards were applied in these vaccines’ development. Additionally, Pfizer enrolled 43,000 participants in the testing. Moderna enrolled 30,000 participants. The number of those involved in the trials align with the standards set for other trials.

Finally, although vaccine manufacturers normally wait until a vaccine is approved before they begin mass production, instead the manufacturers began to make the vaccines months before hand so that there were supplies available as soon as vaccines were approved.

Are the vaccine ingredients safe?

The ingredients in the coronavirus vaccines are safe. Millions of people have received vaccinations and yet serious side effects are extremely rare. This includes people with allergies.

Moderna: mRNA, lipids (SM-102, polyethylene glycol [PEG] 2000 dimyristoyl glycerol [DMG], cholesterol, and 1,2-distearoyl-sn-glycero-3-phosphocholine [DSPC]), tromethamine, tromethamine hydrochloride, acetic acid, sodium acetate, and sucrose.

Moderna Fact Sheet

Pfizer-BioNTech: mRNA, lipids ((4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate), 2 [(polyethylene glycol)-2000]-N,N-ditetradecylacetamide, 1,2-Distearoyl-sn-glycero-3- phosphocholine, and cholesterol), potassium chloride, monobasic potassium phosphate, sodium chloride, dibasic sodium phosphate dihydrate, and sucrose.

Pfizer BioNTech Fact Sheet

Johnson & Johnson/Janssen: recombinant, replication-incompetent adenovirus type 26 expressing the SARS-CoV-2 spike protein, citric acid monohydrate, trisodium citrate dihydrate, ethanol, 2-hydroxypropyl-β-cyclodextrin (HBCD), polysorbate-80, sodium chloride.

Johnson & Johnson Janssen Fact Sheet

I heard mRNA vaccines (Pfizer and Moderna) are brand new and some people have concerns they are not well tested. Are there resources available to help us understand this better?

It is correct that the mRNA vaccines are a new type of vaccine, but a type that has been studied for a number of years. The Centers for Disease Control and Prevention offers a great article about mRNA vaccines, including the safety and history of this type of vaccine.

How do viral vector vaccines (like Johnson & Johnson) work?

The coronavirus is studded with proteins that it uses to enter human cells. These so-called spike proteins are the target for potential vaccines. The Johnson & Johnson vaccine is based on the virus’s genetic instructions for building the spike protein. But unlike the Pfizer-BioNTech and Moderna mRNA vaccines, which store the instructions in single-stranded RNA, the Johnson & Johnson uses a more traditional virus-based technology.

Why was there a pause in the use of the Johnson & Johnson vaccine?

As with any new agent development, as millions of people receive the vaccine, rare potential side effects are identified. Out of an abundance of caution, on Tuesday April 13, the Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) paused the administration of the Johnson & Johnson (J&J) COVID-19 vaccine due to a small number of serious side effects. This pause was lifted by the CDC and FDA on Friday, April 23. Women younger than 50 years old especially should be aware of the rare risk of blood clots with low platelets after vaccination, and that other COVID-19 vaccines are available where this risk has not been seen. If you have received (or want to receive) a J&J/Janssen vaccine, here is what you need to know.

How effective are the Pfizer and Moderna vaccines?

Based on evidence from clinical trials, the Pfizer-BioNTech vaccine was 95% effective, and the Moderna vaccine was 94.1% effective, at preventing laboratory-confirmed COVID-19 illness in people without evidence of previous infection. Both have been shown to greatly reduce the likelihood of severe illness and hospitalization, to a tiny percent of those vaccinated who do contract COVID-19.

How effective is the Johnson & Johnson vaccine?

Across all trial sites, the Johnson & Johnson vaccine showed 85% efficacy against severe forms of COVID-19 and 100% efficacy against hospitalization and death.

The Johnson & Johnson vaccine efficacy was not as high in preventing mild disease as the Pfizer and Moderna vaccine efficacies in their studies. Should I insist on getting the Pfizer or Moderna vaccine instead?

Johnson & Johnson’s one-shot vaccine was tested during a phase of the pandemic that was more complicated, when variants of the virus had already emerged. Even then, it was more than 80% effective at preventing severe illness, including in places where variants of the virus were already circulating.

“Don’t get caught up, necessarily, on the number game, because it’s a really good vaccine, and what we need is as many good vaccines as possible,” says Dr. Anthony S. Fauci, the government’s top infectious disease expert. “Rather than parsing the difference... accept the fact that now you have three highly effective vaccines. Period.”

What are the benefits of the Johnson & Johnson vaccine?

The Johnson & Johnson vaccine can be stored in a normal refrigerator for at least three months, making it simpler to use than other vaccines that must be kept frozen. And because it is a single shot, it doesn't require a follow-up visit for a booster shot. That means it could be particularly useful in settings where individuals may have trouble returning for a booster.

Which vaccines is UMass Memorial Health using?

We are using all three of the currently approved vaccines, though they are not all offered in every location. For locations where we are offering the Johnson & Johnson vaccine, we also always offer an mRNA alternative that individuals can choose to receive instead.

Why is there a 15-minute waiting period after I receive my vaccination?

Currently, Massachusetts Department of Public Health recommends observing patients for 15 minutes after vaccination out of an abundance of caution. Specifically, they recommend observing for signs of severe allergic reaction because this is a new vaccine, and we don’t yet know whether there might be severe reactions that would occur in 1 in 100,000 individuals. However, if a severe allergic reaction is going to occur, it will usually begin within minutes of vaccination and recognized in the 15-minute waiting period.

Should I expect any side effects from the vaccination?

The vaccines can result in arm pain and swelling, fever, chills, muscle/joint pain, diarrhea and headache. These were a bit more common following the second dose.