COVID Vaccines Compared

Medically Reviewed by Carol DerSarkissian, MD on October 26, 2022
6 min read

There are four COVID-19 vaccines approved for use in the U.S. The Pfizer, Moderna, Novavax, and Johnson & Johnson vaccines are all highly effective in protecting you from the virus that causes COVID-19.

The CDC says there’s a preference for the mRNA (Pfizer and Moderna) COVID-19 vaccines over the Novavax or Johnson & Johnson vaccines. This is based on data from the Advisory Committee on Immunization Practices (ACIP). It discussed vaccine safety, vaccine effectiveness, rare negative side effects, and the U.S. vaccine supply.

The CDC recommends that if you are ages 5 years and up that you get one updated (bivalent) booster if it has been at least 2 months since your last COVID-19 vaccine dose. This last dose can be your final primary series dose or an original (monovalent) booster. If you have received more than one original (monovalent) booster, the CDC still recommends that you get an updated (bivalent) booster.

The Pfizer vaccine received full FDA approval on Aug. 23, 2021, and was no longer under emergency use authorization (EUA). It is now marketed under the name Comirnaty.

Vaccines continue to lower your risk for severe disease, hospitalization, and death, even against the widespread Delta variant of COVID-19.

But each is slightly different. Compare them below. If you’re still not sure which vaccine is best for you, talk to your doctor.

Vaccine developer:PfizerModernaJohnson & JohnsonNovavax
How it worksMessenger RNAMessenger RNAModified cold virus Stabilized form of the coronavirus spike protein
When approved/expected approval Given full FDA approval Aug. 23, 2021Dec. 18, 2021 Feb. 27, 2022Emergency use authorization was granted July 13, 2022 by the FDA
What percentage of people did it protect from getting infected in clinical studies? 95% 94.1% 66.1% globally; 72% in the U.S.; 86% effective against severe disease89.7%
Who is it recommended for?People 5 years and olderPeople 5 years and olderOn May 5, 2022, The FDA limited  its use to those 18 years of age and older for whom other authorized or approved COVID-19 vaccines are not accessible or clinically appropriatePeople 12 years and older
How many shots do you need?Two doses, 3 weeks apartTwo doses, 4 weeks apartOne doseTwo doses, 21 days apart
When might you become eligible for a booster shot?Ages 5 years and older get one updated (bivalent) booster if it has been at least 2 months since their last COVID-19 vaccine dose, whether that was:
Their final primary series dose, or an original (monovalent) booster.
Ages 5 years and older get one updated (bivalent) booster if it has been at least 2 months since their last COVID-19 vaccine dose, whether that was:
Their final primary series dose, or an original (monovalent) booster.
Ages 5 years and older get one updated (bivalent) booster if it has been at least 2 months since their last COVID-19 vaccine dose, whether that was:
Their final primary series dose, or an original (monovalent) booster. Those who received more than one original (monovalent) booster should also get an updated (bivalent) booster.
Ages 12 years and older get one updated (bivalent) booster if it has been at least 2 months since their last COVID-19 vaccine dose, whether that was:
Their final primary series dose, or an original (monovalent) booster.
What are the side effects?Fatigue, headache, chills, muscle pain, especially after the second doseFever, muscle aches, headaches lasting a few days. Effects worse after second dose. Pain where you get the shot, headache, fatigue, muscle painPain and tenderness where you get the shot, fatigue, headache, muscle pain
Any warnings?The FDA issued a warning in June about heart inflammation. Since April 2021, there have been more than a thousand reports of myocarditis and pericarditis. These cases are still relatively low.The FDA issued a warning in June about heart inflammation. Since April 2021, there have been more than a thousand reports of myocarditis and pericarditis. These cases are still relatively low.In July, the FDA issued a warning about an increased risk for  developing Guillain-Barre syndrome.  Risk of thrombosis with thrombocytopenia syndrome (TTS), a  rare and potentially life-threatening condition where blood clots in combination with low levels of blood platelets  may occur one to two weeks following administration of the Janssen COVID-19 Vaccine.Rare incidents of myocarditis and pericarditis have been observed though cases typically occurred within a few days after vaccination.
What about pregnant women and nursing moms?The CDC recommends COVID-19 vaccination for women who are pregnant, breastfeeding, trying to get pregnant now, or those who might become pregnant in the future.  Women who are pregnant or were recently pregnant, are more likely to get very sick from COVID-19 than those who are not pregnant. The CDC recommends COVID-19 vaccination for women who are pregnant, breastfeeding, trying to get pregnant now, or those who might become pregnant in the future.  Women who are pregnant or were recently pregnant, are more likely to get very sick from COVID-19 than those who are not pregnant. The CDC recommends COVID-19 vaccination for women who are pregnant, breastfeeding, trying to get pregnant now, or those who might become pregnant in the future.  Women who are pregnant or were recently pregnant, are more likely to get very sick from COVID-19 than those who are not pregnant. The CDC recommends COVID-19 vaccination for women who are pregnant, breastfeeding, trying to get pregnant now, or those who might become pregnant in the future.  Women who are pregnant or were recently pregnant, are more likely to get very sick from COVID-19 than those who are not pregnant. 
Is there anyone who shouldn’t get the vaccine?People with a history of serious allergic reactions, anyone with a history of allergic reactions to vaccine ingredients, including polyethylene glycol, and anyone with a history of allergic reactions to polysorbatePeople with a history of serious allergic reactions, anyone with a history of allergic reactions to vaccine ingredients, including polyethylene glycol, and anyone with a history of allergic reactions to polysorbateAnyone who’s had an allergic reaction to an ingredient in the vaccine, like polysorbate Not recommended for anyone under the age of 12 or who are allergic to any component of the vaccine.
Any significant side effects? 

Extremely rare cases of anaphylaxis in people who received the vaccine.

Extremely rare cases of Bell's palsy, a type of temporary facial paralysis, reported in people who received the vaccine.

Extremely rare cases of anaphylaxis in people who received the vaccine.

Extremely rare cases of Bell's palsy, a type of temporary facial paralysis, reported in people who received the vaccine.

There is a possible, rare relationship between this vaccine and blood clots with low platelets.Not yet available
What about people with lowered immune function? OK for people whose immune function is lowered by HIV or immunosuppressing drugs if they have no other reasons to avoid it. There is limited safety data in this group. Discuss the benefits and risks with your doctor.OK for people whose immune function is lowered by HIV or immunosuppressing drugs if they have no other reasons to avoid it. There is limited safety data in this group. Discuss the benefits and risks with your doctor.Not yet availableNot yet available
What about people with autoimmune diseases?No data is available on the safety or effectiveness of mRNA vaccines in people with autoimmune disease. People with autoimmune conditions may still get the shots if they have no other reasons to avoid vaccination.No data is available on the safety or effectiveness of mRNA vaccines in people with autoimmune disease. People with autoimmune conditions may still get the shots if they have no other reasons to avoid vaccination.Not yet availableNot yet available
Is the vaccine safe for people with a history of Guillain-Barre syndrome (GBS)?To date, no cases of GBS have been seen in people vaccinated for COVID-19. The CDC says a history of GBS is not a reason to avoid vaccination.To date, no cases of GBS have been seen in people vaccinated for COVID-19. The CDC says a history of GBS is not a reason to avoid vaccination.There’s a possible, but rare, risk in developing Guillain-Barre syndrome after this vaccine.Not yet available