A majority of Americans have received at least one dose of their coronavirus vaccine, according to the Centers for Disease Control and Prevention (CDC) tracker. The vast majority who talked about their COVID-19 vaccine side effects or reactions described them as similar to a flu shot.
The most common side effects are a sore arm and sometimes fever, chills, tiredness and headaches for a day or two, according to the CDC. As reported in both studies, the majority of reactions beyond a sore arm happen after the second dose. Those are all signs your body is building an immune response. Read more: COVID-19 vaccine clinical trial volunteers talk about living with the vaccine since August
In a study released in January, the CDC said the risk of anaphylaxis – a severe allergic reaction – is extremely low. Based on data from people who have received the first of the two recommended doses, only about one in every 90,000 people will experience this adverse reaction. The people most at risk of an adverse reaction are those who have had severe allergic reactions to other medications or food. There have been no deaths. On the other hand, the COVID-19 pandemic has killed more than one out of every 1,000 Americans.
There have been increased reports of cases of inflammation of the heart — called myocarditis and pericarditis — happening after COVID-19 vaccination in the United States. These reports are rare, given the number of vaccine doses administered, and have been particularly in adolescents and young adults. CDC and its partners are actively monitoring these reports by reviewing data and medical records to learn more about what happened and to see if there is any relationship to COVID-19 vaccination. Most patients who received care responded well to medicine and rest and quickly felt better.
Cases reported have occurred mostly in male adolescents and young adults age 16 years or older, more often after getting the second dose of one of the mRNA COVID-19 vaccines than after the first dose, and typically within several days after COVID-19 vaccination. Patients can usually return to their normal daily activities after their symptoms improve, and they should speak with their doctor about return to exercise or sports. CDC continues to recommend COVID-19 vaccination for everyone 12 years of age and older, given the greater risk of COVID-19 illness and related, possibly severe complications. The known and potential benefits of COVID-19 vaccination outweigh the known and potential risks, including the possible risk of myocarditis or pericarditis.
For children age 12 to 18, there is an increased risk of fainting after a COVID-19 vaccine, which is fairly common for adolescents after any vaccine, according to the CDC. For this reason, children age 12 and older are advised to have someone drive them to and from their vaccine appointment.
Learn more about what to expect after getting a COVID-19 vaccine
Learn about COVID-19 vaccine safety monitoring and why the vaccine is safe