Adverse reactions are usually mild to moderate in intensity and resolve within a few days following receipt of the Moderna COVID-19 vaccine, according to the CDC. The most common adverse reactions reported after vaccination in clinical studies included:
- Pain at injection site (92.0%)
- Fatigue (70.0%)
- Headache (64.7%)
- Muscle pain (51.5%)
- Joint pain (46.4%)
- Chills (45.4%)
- Nausea/vomiting (23.0%)
- Axillary swelling and tenderness of the vaccination arm (19.8%)
- Fever (15.5%)
- Injection site swelling (14.7%)
- Injection site redness (10.0%)
It takes time for your body to build protection after any vaccination. COVID-19 vaccines that require 2 shots may not protect you until about 2 weeks after your second shot.
After receiving the COVID-19 vaccination, the side effects you may experience are normal signs that your body is building protection and they should go away in a few days.
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