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

Among vaccine recipients during the Pfizer clinical trials, 8.8% reported experiencing any reaction they considered to interfere with daily activity; the most common symptoms were fatigue (4.2%), headache (2.4%), muscle pain (1.8%), chills (1.7%), and injection site pain (1.4%). Of note, more people experienced these side effects after the second dose than after the first dose.

Among vaccine recipients during the Moderna clinical trials, 9.1% reported local injection site reaction and 16.5% reported side effects with the most common being including fever, headache, fatigue, and muscle aches and pains.

Additionally, no specific safety concerns were identified for the Pfizer and Moderna vaccines in subgroup analyses by age, race, ethnicity, underlying medical conditions, or previous SARS-CoV-2 infection.

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1. Are the available COVID-19 vaccines safe and effective?
2. Is it safe to get my child vaccinated?
3. Why did it take so long for the FDA to make a decision about vaccines for children under 5?
4. Is it safe to get vaccinated if I am pregnant or breastfeeding?
5. How was the vaccine developed so quickly?
6. What ingredients are used in the vaccines?
7. What are the possible side effects of a COVID-19 vaccine?
8. Who is NOT recommended for each vaccine?
9. Can I get COVID-19 from the vaccine?
10. Is Johnson & Johnson’s Janssen COVID-19 vaccine safe?
11. Does the Johnson & Johnson/Janssen vaccine require special precautions?