Serious side effects that would cause a long-term health problem are highly unlikely following a COVID-19 vaccine. Millions of children have received COVID-19 vaccines, and no long-term side effects have been detected.
Long-term side effects following any vaccine are extremely rare. Historically, vaccine monitoring has shown that if side effects are going to happen, they tend to happen within six weeks of a vaccine dose. For this reason, the Food and Drug Administration made sure each of the authorized COVID-19 vaccines was studied for at least eight weeks after the final dose.