Warnings and PrecautionsManagement of Acute Allergic Reactions: Appropriate medical treatment to manage immediate allergic reactions must be immediately available in the event an acute anaphylactic reaction occurs following administration of the vaccines. Monitor vaccine recipients for the occurrence of immediate adverse reactions according to the Centers for Disease Control and Prevention guidelines (
https://www.cdc.gov/vaccines/covid-19/clinical-considerations/managing-anaphylaxis.html).
Myocarditis and Pericarditis: Postmarketing data demonstrate increased risks of myocarditis and pericarditis, particularly within 7 days following the second dose. The observed risk is highest in males 18 through 24 years of age. The CDC has published considerations related to myocarditis and pericarditis after vaccination, including for vaccination of individuals with a history of myocarditis or pericarditis (
https://www.cdc.gov/vaccines/covid-19/clinical-considerations/myocarditis.html).
Syncope (fainting): May occur in association with administration of injectable vaccines. Procedures should be in place to avoid injury from fainting.
Altered Immunocompetence: Immunocompromised persons, including individuals receiving immunosuppressive therapy, may have a diminished response to the vaccines.
Limitations of Vaccine Effectiveness: The vaccines may not protect all vaccine recipients.
Adverse ReactionsAdverse reactions reported in clinical trials for individuals 6 years of age and older following administration of the Moderna COVID-19 Vaccine include pain at the injection site, fatigue, headache, myalgia, chills, nausea/vomiting, axillary swelling/tenderness, fever, erythema at the injection site, swelling at the injection site, and arthralgia.
Adverse reactions in children 6 months through 5 years of age following administration of Moderna COVID-19 Vaccine include pain at the injection site, irritability/crying, fatigue, sleepiness, loss of appetite, headache, fever, myalgia, chills, nausea/vomiting, axillary (or groin) swelling/tenderness, arthralgia, erythema at the injection site, and swelling at the injection site.
Anaphylaxis and other severe allergic reactions, myocarditis, pericarditis, and syncope have been reported following administration of the Moderna COVID-19 Vaccine during mass vaccination outside of clinical trials.
Additional adverse reactions, some of which may be serious, may become apparent with more widespread use of the vaccines.
Reporting Adverse Events and Vaccine Administration Errors
The vaccination provider is responsible for mandatory reporting of the following to the Vaccine Adverse Event Reporting System (VAERS):
vaccine administration errors whether or not associated with an adverse event
serious adverse events (irrespective of attribution to vaccination)cases of myocarditis
cases of pericarditis
cases of Multisystem Inflammatory Syndrome (MIS)
cases of COVID-19 that result in hospitalization or death