Woman wearing a mask with a germ in the background

Coronavirus (COVID-19) Vaccines

A vaccine is a major component of preventing COVID-19. In an unprecedented effort to curb the pandemic, scientists from around the world have come together to condense a 10-year research and development timeline into roughly 10 months. There are over 200 vaccines in development, and dozens are in clinical trials. In the United States, three vaccines have received emergency use authorization from the Food and Drug Administration (FDA). Of those three, one—the Pfizer-BioNTech vaccine—has received full approval from the FDA.

To move at such a rapid pace, researchers explored new vaccine platforms, like mRNA. Manufacturers produced batches of vaccines without waiting for final clinical trial results in order to have them immediately ready if proven safe and effective. In spite of the speed, safeguards like data and safety monitoring boards remained in place throughout the process. A vaccine is only FDA-authorized once it is proven to be safe. 

Learn the Basics of Getting Vaccinated

Frequently Asked Questions

  • Which vaccines are currently available?

    In the U.S., there are currently three available vaccines. The FDA has granted full approval to the Pfizer-BioNtech vaccine, and emergency use authorization to the Moderna vaccine and the Johnson & Johnson vaccine. There are large-scale Phase 3 clinical trials in progress or being planned for two additional COVID-19 vaccines in the U.S.: AstraZeneca’s vaccine and Novavax’s vaccine​.

  • Are the COVID-19 vaccines safe?

    The available COVID-19 vaccines underwent extensive safety and regulatory processes. In order for the vaccines to receive FDA emergency use authorization, each clinical trial was subjected to review from a panel of scientists who are independent of the companies developing the vaccines. These scientists are members of data and safety monitoring boards (DSMB) that review clinical trials of drugs and vaccines. DSMBs have vetted drugs and vaccines for decades.

  • When can I get the COVID-19 vaccine?

    Everyone 12 and older across the U.S. is now eligible to be vaccinated. Appointments, including walk-in appointments, are now readily available nationwide.

  • How do I sign up to get vaccinated?

    The best place to start is your county’s health department website. Vaccines are being distributed locally, and eligibility to sign up may vary. Some counties have vaccine registration portals available, while others are only providing information and phone numbers at this time. Many states are encouraging residents to go to their local county health departments for specific information about making an appointment. You can also search for pharmacies and providers that offer vaccination on Vaccinefinder.org.

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

    Public health officials say to expect largely mild side effects. You may feel pain and redness at the injection site, fatigue, a headache, joint and muscle aches, and/or a fever. Some less common side effects can include swollen lymph nodes (especially in the armpit) and swelling at the injection site. A very rare symptom may include a temporary weakness or paralysis of the facial muscles called Bell’s Palsy. In extremely rare cases, some people who received the Johnson & Johnson vaccine developed a blood clot called cerebral venous sinus thrombosis.

  • Should I get the vaccine if I’ve already had COVID-19?

    Even if you’ve previously been infected with COVID-19 and recovered, experts recommend getting vaccinated. Your natural immune response may not be strong enough to protect you from future infections. If you were treated for COVID-19 with monoclonal antibodies or convalescent plasma, you should wait 90 days before getting a COVID-19 vaccine, according to the CDC. And if you currently have an active case of COVID-19, wait until after the isolation period is over to make your appointment to prevent spreading the virus at the vaccine site. 

  • Should I get the vaccine if I'm pregnant?

    While the vaccines were not tested on pregnant women or those who were breastfeeding, federal health officials are allowing pregnant women to receive the vaccine if they choose. Pregnancy is considered a risk factor for severe COVID-19 illness by the CDC. Both the CDC and the American College of Obstetricians and Gynecologists (ACOG) recommend that pregnant and breastfeeding individuals get vaccinated.

  • Will the vaccines be able to protect against new strains of COVID-19?

    New research found that both the Pfizer and Moderna COVID-19 vaccines will protect against the U.K. and South African variants of the virus. The Johnson & Johnson vaccine is also thought to provide some level of protection against variants, though research is ongoing. Moderna, Pfizer, and Johnson & Johnson are all developing booster shots that may help increase immunity against virus variants. Scientists say the virus would have to mutate extensively to escape the vaccine response. They believe the vaccines will still be protective against new strains that are not significantly different from the original virus.

  • Can I take pain relievers before or after getting vaccinated?

    In order to ensure the vaccine is as effective as possible, some experts are recommending against taking over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) before or after you get injected in an effort to prevent or soothe side effects. NSAIDS include well-known pain relievers such as aspirin, ibuprofen (Advil, Motrin), and naproxen (Aleve). A recent study found that NSAIDS dampen the production of protective antibodies against the virus. If you can’t tolerate symptoms post-vaccine, experts recommend using acetaminophen (Tylenol) over an NSAID. If you take NSAIDS long-term for chronic conditions, you should continue following your prescription.

  • How long will it take for the vaccine to work?

    While your body likely will build some immunity to the virus shortly after receiving the single-dose COVID-19 vaccine or the first dose of a two-shot regimen, you won’t be fully protected. To reach full protective immunity, current research suggests you will have to wait two weeks after your second dose for the Pfizer and Moderna vaccines or two weeks after your single dose of the Johnson & Johnson vaccine. 

  • How long will immunity from the vaccine last?

    Some experts believe immunity from the virus will likely last at least a year, and Moderna reports its vaccine will likely provide immunity for at least that period of time. It’s possible you may have to receive the shot annually like a flu shot in order to boost waning immunity. The FDA has recommended Pfizer and Moderna vaccine recipients who are immunocompromised, 65 and older, or at high risk for serious COVID-19 receive a booster six months after their initial vaccine regimen. The FDA recommends all Johnson & Johnson vaccine recipients 18 and older get a booster two months after their shot.

  • What is safe to do after I’ve been fully vaccinated?

    If you’ve been fully vaccinated and are two weeks past the date of your second shot—or your first shot in the case of the Johnson & Johnson vaccine—the CDC says you may begin to loosen safety precautions. According to CDC guidance, you can forego face masks and resume activities that you did prior to the pandemic. The CDC also says domestic travel is considered “low-risk” for fully vaccinated people.

  • Can I still transmit the virus if I’ve been vaccinated?

    The CDC released real-world data showing that the COVID-19 vaccines prevented transmission among healthcare personnel, essential workers, and first responders. But experts say only time will tell if this data will continue to hold up—though it’s likely it will. Early data from Israel shows that the Pfizer vaccine may be effective at preventing transmission of the virus. Johnson & Johnson data also suggests that the vaccine may curb asymptomatic transmission. While the CDC has released guidance stating that people who are fully vaccinated against COVID-19 don’t need to quarantine or test after being exposed to the virus if asymptomatic, experts haven’t taken a hard and fast stance in regards to transmission. 

  • Do I still need to wear a mask after I get vaccinated?

    CDC guidance says you can safely stop wearing your mask indoors and outdoors. But you’ll still need to wear a mask if it’s mandated by your county, state, workplace, or business you’re entering. You can also expect to stay masked up on public transportation like planes, buses, and trains. If you are immunocompromised, the CDC encourages you to wear a mask, even if you’re fully vaccinated.

  • Will the coronavirus vaccine be mandatory?

    Experts believe it’s unlikely the government will institute a COVID-19 vaccine mandate to protect public health. Instead, the government will likely release recommendations and national standards for the vaccine. Vaccination requirements may be implemented through employers and schools—both of which have instituted vaccine requirements in the past.

How the Vaccine Works in the Body

Explore interactive models that show how the human body responds to a COVID-19 vaccine, and what the body of a vaccinated person would do if exposed to the SARS-CoV-2 virus.

Pregnant woman washing hands in the bathroom.
Vaccinated Pregnant Women Pass COVID-19 Immunity to Their Newborns
An illustration of a Black therapist with glasses talking to a young patient through a laptop screen.
Here's How Therapists Could Combat Vaccine Hesitancy
A bunch of vaccine ampules lined up; they are labeled COVID-19 vaccine.
Are COVID-19 Booster Shots Variant-Specific?
three vaccine syrignes
FDA Greenlights ‘Mixing and Matching’ COVID-19 Vaccine Boosters
A white nurse administering a vaccine to a black man.
Op-Ed: It’s Unacceptable That Disabled People Still Can’t Access COVID Vaccines
An older adult woman with a scarf on her head looking at a male healthcare worker's hand, which is cleaning a spot on her arm to deliver a vaccine.
Experts: All Blood Cancer Patients Should Get a COVID Booster
CDC Director Rochelle Walensky
CDC Director Overrules Panel to Include Frontline Workers in Booster Rollout
Products used during penstruation.
Researchers Will Examine Link Between COVID-19 Vaccines and Period Changes
Older woman excited about getting COVID vaccine.
Getting a COVID-19 Vaccine Is Good for Your Mental Health
An illustration of a Black woman standing in a window.
Do Vaccinated People Have to Quarantine If They're Exposed to COVID?
Pfizer vaccine fridge
FDA Authorizes Pfizer Booster for Seniors and High Risk Groups. What's Next?
A bunch of COVID vaccine ampules neatly lined up on a blue background.
If You Got the J&J Vaccine, Here's What You Should Know About Boosters
Delta plane flying near a COVID-19 testing sign
U.S. to End 18-Month Air Travel Ban for Fully Vaccinated Visitors
elementary school children return to in-person classes
COVID-19 Vaccine May Be Coming for Younger Children Soon, Pfizer Says
Two ampules of COVID-19 vaccine next to a syringe on a blue background.
Advisory Panel Says FDA Should Save COVID Boosters for the Most Vulnerable
Person getting a COVID vaccine.
Here’s Why Your Employer May Be Mandating COVID-19 Vaccines Soon
Vaccine shot resting on a globe.
COVAX Estimates Having 25% Fewer COVID Vaccines for 2021 Global Distribution
Hands reaching for booster shot vial.
Who Can Get a COVID-19 Vaccine Booster Shot?
Person receiving a shot in the arm.
Moderna Is Developing a Combination COVID-19 and Flu Booster Shot
Man receiving a COVID-19 vaccine.
Here's Why You Don't Need to Worry About Waning COVID-19 Antibodies
Child receiving a COVID-19 vaccine.
LA School District Mandates COVID-19 Vaccine for Children 12 and Up
Moderna COVID-19 vaccine vial.
Moderna Produces More Antibodies Than Pfizer COVID-19 Vaccine, Study Finds
President Joe Biden COVID-19 Plan
Biden’s Assertive COVID-19 Vaccination Plan Will Affect Most Americans
Young adolescent receiving a vaccine.
Getting Vaccinated May Reduce Your Risk of Long COVID
Hands reaching for booster shot vial.
A Verywell Report: Vaccinated People Hold on to Hope of Boosters
man spraying intranasal COVID vaccine up nose
COVID Booster Shots Administered in the Nose May Be Better Than the Arm
Las Vegas Raiders vs San Francisco 49ers
NFL Kicks Off Season With Impressive Vaccination Rate Among Players
Hands up if you got vaccinated
Moderna's Half-Dose Booster May Expand Global Vaccine Supply
woman sitting at desk showing proof of vaccination on phone
Here’s What U.S. Employers Are Doing to Encourage Vaccination
COVID-19 vaccination clinic.
Are COVID-19 Booster Shots Free?
person at vaccination site sitting with nurse while others wait
What Are COVID Booster Shot Side Effects Like?
vaccine vials
Here's Why COVID Vaccine Hesitancy Is Finally Shrinking
Older woman getting a COVID-19 vaccine.
Can You Mix and Match COVID-19 Boosters?
A young Black woman in a car holding up her phone with has a "Certificate of verification" for her COVID vaccine status.
4 Ways to Prove Your COVID-19 Vaccination Status
An unseen person wearing a face mask with whales on it; they have a band aid on her arm where she got a shot.
CDC: You Can Get the Flu Shot and a COVID Vaccine Together
vaccination campaign in new york
Why Do Health Officials Suggest Getting COVID-19 Booster Shot After 8 Months?
heart health
COVID-19 Poses Higher Risk of Heart Inflammation Than Vaccines
An illustration of a gloved hand injecting a globe with a syringe; there are red COVID virus particles on a light red background.
Is the U.S. COVID Booster Plan Ethical?
Older woman receives a vaccine and doctor is placing bandaid on her arm.
Experts Divided Over Current Need for COVID Booster Shots
Close up of a blue sign with white letters that says "COVID vaccination site by appointment only please do not enter if you have any covid symptoms" an older person in a blue jacket is standing to the left of the side but they are not in focus.
Where Can You Get a COVID-19 Booster?
Close up of a white person's hands holding a laminated COVID vaccine card.
What Should You Do If You Laminated Your COVID-19 Vaccine Card?
Jassen COVID-19 Vaccine on shelf
Johnson & Johnson Says Its Booster Shot Raises Antibody Levels 9-Fold
child with face mask
Experts Warn Against Off-Label Use of COVID-19 Vaccines for Children Under 12
Older man looking at his arm where he was vaccinated.
Are Booster Shots Common for Vaccines?
Johnson & Johnson COVID vaccine.
Why You Shouldn't Count Out the Johnson & Johnson Vaccine
Comirnaty vaccine card
Same Vaccine, New Name. Why Did Pfizer Choose Comirnaty?
health insurance bills
Will Unvaccinated People Have to Pay More for Health Insurance?
vaccine and variants
FDA Grants Full Approval to Pfizer COVID-19 Vaccine
Los Angeles nursing home
Nursing Homes Will Have to Vaccinate Workers or Risk Losing Federal Funding
newborn baby with mother
New Studies Confirm COVID-19 Vaccines Are Safe for Pregnant People
Johnson and Johnson storefront.
Data Suggests Johnson & Johnson Vaccine Still Effective Against Delta Variant
President Joe Biden COVID-19 Presser
White House: Most Americans Will Need Booster Shot 8 Months After Vaccination
Mom and daughter using a COVID proof app.
These U.S. Cities Are Requiring Proof of Vaccination for Indoor Activities
Two researchers carrying a vaccine syringe illustration.
What Will Full FDA Approval Change for COVID-19 Vaccines?
Three vials of medication and a syringe.
FDA Authorizes COVID-19 Booster Shots for People Who Are Immunocompromised
Man unsure about getting vaccinated.
A Verywell Report: What Changed the Minds of the Vaccine Hesitant?
People at an office wearing face masks.
CNN Fires Some Unvaccinated Employees. Can Your Employer Do That?
COVID-19 vaccination card
How to Spot Fake COVID-19 Vaccination Cards
Screenshots from NYC COVID Safe
How to Show Proof of Vaccination in New York City
Young teen getting vaccinated.
White House Plans a New Push to Get Students Vaccinated
More In Coronavirus (COVID-19)
Page Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. United States Food and Drug Administration. COVID-19 Vaccines. Updated February 27, 2021.

Additional Reading