Four COVID Vaccines Compared
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Two COVID vaccines have already been approved for use in the United States and two more could be approved within the next few months. Here’s what we know about each vaccine’s efficacy.
| Vaccine developer: | Pfizer | Moderna | AstraZeneca | Johnson & Johnson |
|---|---|---|---|---|
| When approved/expected approval | Dec. 11 | Dec. 18 | Could submit application for emergency use authorization in late March. | Submitted application for emergency use authorization on Feb. 5. |
| What percentage of people did it protect from getting infected in clinical studies? | 95% | 94.1% | 70% | 66% |
| How many shots do you need? | Two doses, 3 weeks apart | Two doses, 4 weeks apart | Two doses, a month apart | One dose |
| What are the side effects? | Fatigue, headache, chills, muscle pain, especially after the second dose. | Fever, muscle aches, headaches lasting a few days. Effects worse after second dose. | Injection site pain, fever, muscle aches, headache. | Not yet available. |
| How many doses will be available, and when? | 50 million, starting Dec. 18; 1.3 billion in 2021. | 20 million, starting Dec. 21; 80 million for U.S. in 2021. | 3 billion planned for 2021. | Not yet available. |
| Who is it recommended for? | People 16 years and older. | People 18 years and older. | Not yet available. | Not yet available. |
| What about pregnant women and nursing moms? | Pregnant women or nursing moms who want the COVID-19 vaccine should get one, experts say. The vaccine has not yet been studied in pregnant women. Read guidelines here. | There’s limited data. Studies in rats who were immunized before and during pregnancy found no safety concerns. The CDC says pregnant women may choose to receive the vaccine. | Not yet available. | Not yet available. |
| 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 polysorbate. | 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 polysorbate. | Not yet available. | Not yet available. |
| Any significant side effects? | 50 cases of anaphylaxis in people who received the vaccine, mostly women.
Four cases of Bell’s palsy, a type of temporary facial paralysis, reported in people who received the vaccine. This is not more than would be expected in the general population. |
21 cases of anaphylaxis in people who received the vaccine, all in women.
Four cases of Bell’s palsy reported in the clinical trials including 3 in the vaccine group, and 1 in the placebo group. This is not more than would be expected in the general population. |
Four total serious side effects, including two cases of transverse myelitis. | One person went to the hospital for fever associated with the vaccine. Four other serious cases were not related to the vaccine. |
| 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. | 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. | Not yet available. | Not yet available. |
| What about people with autoimmune diseases? | No data are 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 are 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 available. | Not 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. | Not yet available. | Not yet available. |
