Increased Reports of Myocarditis and Pericarditis After Pfizer and Moderna Vaccinations: "Seek Medical Attention if Experiencing Chest Pain or Shortness of Breath" (Update)

About 4.1 Cases per Million... Distribution of Guidelines for Medical Personnel

[Image source=Reuters Yonhap News]

[Asia Economy Reporter Seo So-jeong] The government has decided to strengthen the response system following an increase in reports of adverse reactions such as myocarditis and pericarditis after receiving messenger RNA (mRNA) vaccines like Pfizer and Moderna overseas.

The COVID-19 Vaccination Response Promotion Team (Director Jeong Eun-kyung) announced on the 29th that due to the rare but increasing reports of myocarditis and pericarditis after COVID-19 mRNA vaccination abroad, it established and distributed related guidelines on the 28th to strengthen the response system for related adverse reactions domestically.

Myocarditis is a disease causing inflammation in the heart muscle, and pericarditis is inflammation of the membrane surrounding the heart. In the United States, since April, 1,226 cases of myocarditis and pericarditis have been reported after 300 million mRNA vaccine doses. As of the 11th, about 4.1 cases occurred per 1 million mRNA vaccine doses administered.

The reported cases were mainly among male adolescents and young adults, with most symptoms occurring within 4 days after vaccination, and a higher frequency after the second dose. The majority of patients improved rapidly after treatment and rest.

The Promotion Team formed an advisory group including relevant experts to strengthen management of myocarditis adverse reactions, discussing case definitions, reporting, and management measures for myocarditis and pericarditis, and distributed medical guidelines on the 28th.

May Impair Heart Pumping Leading to Heart Failure... Most Improve After Treatment

The Promotion Team urged that if symptoms such as chest pain, pressure, discomfort, difficulty breathing, shortness of breath, pain when breathing, or rapid or irregular heartbeat occur after COVID-19 vaccination, individuals should promptly seek medical care, and medical institutions treating such patients should report the adverse reactions.

Jo Eun-hee, head of the Safety Vaccination Management Division of the Promotion Team, stated, "The U.S. Food and Drug Administration (FDA) and the United Kingdom have attached warning messages regarding myocarditis and pericarditis after mRNA vaccination," adding, "If the European Medicines Agency (EMA) and the World Health Organization (WHO) register these as side effects in July, the Ministry of Food and Drug Safety will review and officially register them as side effects domestically."

Jo added, "Myocarditis and pericarditis can impair the heart’s pumping function, potentially causing heart failure. Although most cases improve with treatment, in severe cases, devices such as left ventricular assist devices or extracorporeal membrane oxygenation may occasionally be needed to protect the heart. Therefore, if symptoms occur, it is best to promptly visit medical professionals for diagnosis and treatment."

This content was produced with the assistance of AI translation services.