Answers to Common Questions About the COVID-19 Vaccines

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Answers to Common Questions About the COVID-19 Vaccines

Holly Phillips, MD
By Holly Phillips, MD
Jan 20, 2021 - Updated Apr 14, 2021
Answers to Common Questions About the COVID-19 Vaccines

Last year at this time, few if any of us had any idea how COVID-19 would upend the world as we knew it. After many months of challenges, 2021 is offering new hope as three effective vaccines are poised to give us the upper hand for the first time in our battle against the deadly virus.

Getting everyone vaccinated should be our top priority.

High-risk populations have been the first in line to receive vaccines, yet widespread vaccination of lower-risk populations is just as critical to slowing the spread of COVID-19. These vaccines are unequivocally the key to bringing the pandemic to an end.

As we await our turn to roll-up our sleeve, many people have questions about the vaccines. Here are answers to eight common questions about the COVID-19 vaccines.

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Can the COVID-19 vaccine give me COVID-19?

No. It’s scientifically impossible to contract the coronavirus from the vaccines currently approved for use. Getting vaccinated also won’t cause you to test positive on viral tests.

What coronavirus vaccines are available?

Right now, three vaccines are being administered in the U.S. They are made by Pfizer/BioNTech, Moderna, and Johnson & Johnson (in partnership with Janssen Pharmaceuticals). The Pfizer/BioNTech and Moderna vaccines require two doses. The Johnson & Johnson COVID-19 vaccine requires one dose.

On April 13, 2021, the Centers for Disease Control (CDC) and the Food and Drug Administration (FDA) recommended pausing the Johnson & Johnson (in partnership with Janssen Pharmaceuticals) vaccine, to review six reported cases of a rare and severe type of blood clot in individuals who received the Johnson and Johnson vaccine.

Moderna and Pfizer/BioNTech COVID-19 Vaccines

The Moderna and Pfizer/BioNTech use messenger RNA (mRNA) to instruct cells in the body to make a “spike protein” which is also found on the surface of the Coronavirus.

The body’s immune cells then recognize the protein and build antibodies to it, protecting you from getting sick from the virus if you’re exposed. The vaccines don’t contain the live virus (or inactivated virus) and hence cannot give you the illness.

Johnson & Johnson COVID-19 Vaccine

The Johnson & Johnson coronavirus is a type of vaccine known as a viral vector vaccine. It was developed using the same safe, effective technology that has been used to create a vaccine for Ebola, for example. This vaccine relies on using a harmless adenovirus (that won’t make you sick) to deliver a blueprint of the protein spike cells. Your immune system is then able to recognize the spikes and protect you from getting sick.

Why do I need 2 shots of certain COVID-19 vaccines?

The Pfizer and Moderna vaccines require a series of 2 shots, which is not unusual to reach peak effectiveness. Consider that some childhood vaccines require 4 doses over time. Repeat dosing helps your immune system better recognize the virus and mount its strongest defense.

The first and second shots are identical, just given at different times.

How soon after my vaccine will I be protected from COVID-19?

It takes about 14 days for your body to build up immunity from the single-dose Johnson & Johnson vaccine and about 14 days after the second dose of Pfizer and Moderna vaccines to build up immunity to COVID-19.

It is important to note that it’s still possible to contract COVID-19 in between doses. So, while we can enjoy a much welcomed sense of relief after getting vaccinated, face masks, social distancing, and COVID-19 protocols should remain a part of our daily routine.

How effective are the COVID-19 vaccines?

The Pfizer-BioNTech vaccine is approximately 52% effective after the first shot and the Moderna vaccine is approximately 80% effective after one dose. After a second dose 3 to 4 weeks later, both vaccines approach 95% effectiveness.

The Johnson & Johnson vaccine has been shown to be 86% effective at preventing severe illness in COVID-19, and in trials has shown to be 100% effective in preventing hospitalizations.

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Do I still need the vaccine if I already had COVID-19?

The short answer is yes, but you may not need to rush to the front of the line.

From what we know, most people who recover from COVID-19 develop natural immunity which protects them from getting sick with the virus again. The catch is that it’s unclear how strong that immunity is or how long it lasts. The immunity likely varies from person to person and depends on a host of factors, like age and underlying conditions.

On the flip side, while we know the available vaccines are incredibly effective in preventing COVID-19, in fairness, we don’t yet know how long their immunity will last either, although it’s likely the protection will last at least a year or two.

With so much unknown, it’s especially important to focus on what we do know: Getting vaccinated will help protect not just you but also those around you by decreasing the spread of the illness.

As for timing, since it’s uncommon for people who have recovered from the virus to contract it again within 90 days, it may not be necessary to try to rush to be vaccinated before then. However, the guidelines emphasize that those who qualify to get the vaccine should do so without delay. If you choose to wait, just make sure to keep it at the top of your to-do list.

What are the side effects of the COVID-19 vaccine?

After getting the vaccine you may experience some mild symptoms for 24-48 hours, which are normal signs that your immune system is responding as it should. Even though the flu shot and the COVID-19 vaccine work in completely different ways, their most common side effects are similar.

Side effects of the COVID-19 vaccine may include:

  • Pain or swelling and the injection site
  • Fever/chills
  • Muscle aches
  • Headache
  • Fatigue

These symptoms should not last longer than a day or two. Pain at the injection site can be soothed by a cool washcloth and massage. Stretching your arm or doing some light exercise can also help.

The risk of experiencing a severe allergic reaction after receiving the vaccine is very rare, about .001% possibility based on available data so far.

Nonetheless, it's important to be aware of the possibility and talk to your doctor if you are concerned. People with a history of extreme allergic or anaphylactic reactions to other vaccines are most at risk.

The Centers for Disease Control and Prevention (CDC) recommends remaining at the clinic where you receive your vaccine for 15 minutes for close monitoring once the vaccine is administered. For those with a history of allergies, you may be asked to wait 30 minutes to monitor any side effects.

If you do have a history of allergies to vaccines, you may still be able to be vaccinated for COVID-19. An allergist can conduct monitored skin testing in their office and administer portions of the vaccine over several visits until the full dose is reached.

Will I have to pay for the COVID-19 vaccine if I don’t have insurance?

The COVID-19 vaccine is available free of charge to anyone who wants it as part of the Coronavirus Aid, Relief, and Economic Security (CARES) Act. Commercial insurances as well as Medicare and Medicaid must cover the vaccine in full and will be reimbursed.

If you don’t have any insurance your vaccine is still covered and is expected to remain cost-free for all of 2021. Some private vaccination providers may charge administration fees which will be paid by the patient’s insurance or the Provider Relief Fund, at no out-of-pocket expense to the patient.

Importance of Getting Your COVID-19 Vaccine

The COVID-19 vaccine is an incredibly important next step in stopping the spread of the coronavirus. Always make sure to ask your doctor questions in advance to help ease any concerns. Please keep in mind that wearing a face mask in public, social distancing, and practicing healthy habits must continue even after vaccination.

Holly Phillips, MD

Holly Phillips, MD

Dr. Holly Phillips, a Board-Certified General Internist in private practice, is a journalist, author, television contributor, and medical expert for RxSaver. Featured regularly across multiple media outlets, Dr. Phillips first gained nationwide recognition as a Medical Contributor to CBS News and “Core Member” of the Dr. Oz Show. Frequently quoted in print, she has been a contributing editor for Prevention, and appeared in feature articles for Vogue, Self, and others. Dr. Phillips is the author of the book, “The Exhaustion Breakthrough,” published by Rodale. Dr. Phillips obtained her medical degree from Columbia University College of Physicians and Surgeons and trained at Lenox Hill Hospital. In practice, she addresses all Internal Medicine Conditions with a focus on preventive women’s health. Dr. Phillips is well versed in the foundations of complementary and alternative medicine and views these ideas as integral to the practice of medicine today. She lives in Manhattan with her husband, two young daughters and Pug.

The information on this site is generalized and is not medical advice. It is intended to supplement, not substitute for, the expertise and judgment of your healthcare professional. Always seek the advice of your healthcare professional with any questions you may have regarding a medical condition. Never disregard seeking advice or delay in seeking treatment because of something you have read on our site. RxSaver makes no warranty as to the accuracy, reliability or completeness of this information.

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