Safe & Effective Vaccines for COVID-19

Vaccines for COVID-19 help reduce damages from the coronavirus pandemic. The vaccines:

  • help fewer people be infected.
  • lower the number of people who have to be cared for in the hospital.
  • reduce the long-term effects of COVID-19.
  • lower the number of deaths from COVID-19.

The Pfizer/BioNTech (FDA-approved for people ages 16 and older and authorized for use in children ages 5 to 15) and Moderna mRNA vaccines, and the vaccine made by Janssen (a Johnson & Johnson company), are the only COVID-19 vaccines authorized for use in the United States.

In most situations, the Centers for Disease Control & Prevention (CDC) prefers COVID-19 vaccines and boosters made by Pfizer/BioNTech or Moderna over Janssen. This is due to the risk of serious adverse effects.


COVID-19 Vaccines & Booster Shots Available

COVID-19 can be a serious disease. U of U Health recommends getting vaccinated as soon as possible. The COVID-19 vaccine is freely available to anyone who lives in the US and is 5 years of age or olderVisit or call 1-800-232-0233 to find a vaccine provider with available appointments near you. 

U of U Health is currently offering limited appointments for the Pfizer/BioNTech vaccine, in addition to booster shots for eligible populations. Schedule an appointment at U of U Health.

Find a Vaccine Provider

Why Should I Get the COVID-19 Vaccine?

Vaccine Effectiveness

The Pfizer-BioNTech, Moderna, and Janssen (a Johnson & Johnson company) vaccines are effective at preventing serious illness, hospitalization, and death from COVID-19. However, the CDC prefers people get the Pfizer/BioNTech or Moderna COVID-19 vaccine in most situations. This is due to the risk of adverse side effects from the Janssen vaccine.

You will need two doses of the Pfizer/BioNTech or Moderna vaccines to fully protect you against COVID-19. The Johnson & Johnson vaccine only requires one dose. It takes about two weeks after the final dose of each vaccine to reach full immunity.

View our COVID-19 vaccine infographic to learn more about the different vaccines.

Vaccine Side Effects

Temporary, flu-like symptoms that typically resolve one to two days after vaccination are normal and a sign that your immune system is building up protection against disease. Side effects for the COVID-19 vaccines include:

  • mild pain, swelling, or redness at the injection site where you get the vaccine;
  • fever, usually mild and short-lived;
  • chills;
  • feeling tired;
  • headache;
  • muscle and joint aches;
  • diarrhea (seen in Pfizer/BioNTech clinical trials);
  • nausea (seen in Moderna clinical trials); and
  • swollen lymph nodes in the same arm as the injection site (seen in Moderna clinical trials). 

Some people who received the vaccine reported worse fevers and aches than others. Side effects were usually short-lived and able to be managed with fever-reducing medications, such as Tylenol. For people who received the Pfizer/BioNTech or Moderna vaccine, side effects were more common after the second dose than the first dose. 

Heart Inflammation Symptoms

Some people—particularly male adolescents and young adults—who received the mRNA vaccines (Pfizer/BioNTech & Moderna) reported symptoms of myocarditis or pericarditis (heart inflammation conditions) within several days of getting their shot. This rare adverse reaction occurred more often after the second dose of vaccination. But with proper treatment and care, most patients saw their symptoms improve quickly. However, it's important to keep in mind that the known risks of COVID-19 illness, such as long-term health problems, hospitalization, and even death, far outweigh the risks of having a rare adverse reaction to the vaccines.

TTS Symptoms

People—particularly women younger than 50—who receive the Janssen (Johnson & Johnson vaccine) should be aware of an increased risk for a rare and serious, but treatable, blood clotting condition called thrombosis with thrombocytopenia syndrome (TTS). Due to these concerns, the CDC prefers people get the vaccine made by Pfizer/BioNTech or Moderna if they can.

TTS symptoms include:

  • shortness of breath,
  • chest pain,
  • leg swelling,
  • persistent abdominal pain,
  • severe or persistent headaches or blurred vision, or
  • easy bruising or tiny blood spots under the skin beyond the site of the injection.

Anyone who experiences these symptoms within three weeks after vaccination should call their provider or visit urgent care or the emergency department as needed. 

People who have had an episode of heparin-induced thrombocytopenia (HIT) should not receive the Janssen (Johnson & Johnson) COVID-19 vaccine within 90-180 days of their illness. Talk to your health care provider if you want to learn more before receiving the vaccine. See additional information for people with a history of thrombosis or risk factors for thrombosis.

Allergic Reactions to Vaccines

Severe allergic reactions or anaphylaxis to vaccines are extremely uncommon. If a severe allergic reaction does occur, it typically happens within a few minutes to one hour after receiving the vaccine. However, some people have experienced non-severe allergic reactions (i.e., hives, swelling, and wheezing) within four hours after getting vaccinated.

You should not get the COVID-19 vaccine if:

  • you have had a severe allergic reaction after the first dose of the Pfizer/BioNTech or Moderna vaccine.
  • you have had a severe allergic reaction to any ingredient in the vaccine.
  • you are allergic to polyethylene-glycol (ingredient in Pfizer/BioNTech and Moderna vaccines) or polysorbate (ingredient in the Johnson & Johnson vaccine that is closely related to PEG). 

For a list of vaccine ingredients, see the ModernaPfizer-BioNTech, and Janssen (Johnson & Johnson company) fact sheets.

People with a history of immediate allergic reactions — even if it was not severe — to other vaccines or injectable therapies should consult with their doctor before getting the COVID-19 vaccine, according to CDC recommendations.

I Had COVID-19. Should I Get the Vaccine?

We don’t know if or for how long after infection you will be protected from getting COVID-19 again. Health experts recommend you get the vaccine even if you have been infected by COVID-19.

Have More Questions about the COVID-19 Vaccine?

Visit our FAQs page for expert-based answers

Vaccine Cost

The COVID-19 vaccine will be given to everyone at no out-of-pocket cost. However, your insurance company will be billed a vaccine administration fee to cover vaccination operations costs. For those without insurance coverage, assistance programs will cover the administrative fee. Nobody will be denied a vaccine if they can’t afford to pay.

Social Distancing & Masking Guidelines after Vaccination

Clinical trials show the vaccines will protect you from getting ill from COVID-19. According to CDC guidelines, fully vaccinated people can resume most indoor and outdoor activities without wearing a mask or physically distancing from others, except in:

  • in healthcare settings.
  • if you are in a public indoor setting in an area of substantial or high transmission.
  • when required by laws, rules, or regulations, including local business and workplace policies. 

You are considered fully vaccinated:

  • two weeks after your second dose in a two-dose series, such as the Pfizer/BioNTech or Moderna vaccines.
  • two weeks after a single-dose vaccine, such as Johnson & Johnson’s Janssen vaccine.

Watch our experts to learn more about the COVID-19 vaccine and why you should get it.

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