KUALA LUMPUR: Only 25 cases of myocarditis (inflammation of the heart muscle) were detected within 21 days post Covid-19 vaccination out of 433,674 admissions to 216 hospitals between February and September 2021.
Health director-general Tan Sri Dr Noor Hisham Abdullah said of the total, 14 cases were related to the Covid-19 Comirnaty vaccine manufactured by Pfizer, nine were associated with CoronaVac (Sinovac) and two more involving Oxford-AstraZaneca.
He said the vaccine safety study known as the Case-Based Monitoring of Adverse Events Following Covid-19 vaccination (SafeCovac) was conducted by the Institute for Clinical Research, National Institutes of Health.
"The SafeCovac study found that the absolute incidence rate of myocarditis per million doses administered was 0.9 for Comirnaty recipients, 0.5 for CoronaVac and 0.7 for Oxford-Astra Zaneca vaccines.
"Among those under 30 years of age, the absolute rate of myocarditis events was 0.87 per million doses administered for Comirnaty and 0.49 for CoronaVac, while for individuals aged 30 years old and above, the absolute rate was 1.0 per million doses for Comirnaty and 0.6 for CoronaVac," he said in a statement here on SAturday (Jan 15).
Dr Noor Hisham said the SafeCovac findings, National Pharmaceutical Regulatory Agency (NPRA)-Adverse Event Following Immunisation (AEFI) reports and real-world data are consistent with a very rare incidence of myocarditis after receiving the Comirnaty vaccine compared to the higher risk of developing myocarditis from Covid-19 infection.
"Furthermore, the vast majority of reported myocarditis cases were mild, self-limited, and spontaneously resolved," he said.
On concerns over cases of vaccine-associated myocarditis and pericarditis especially those using the Messenger Ribonucleic Acid (mRNA) technology including Comirnaty for the adolescent population, Dr Noor Hisham said over 33 million doses of mRNA-based vaccines were administered in the country.
"NPRA has not detected any 'Safety Alert' to prove the adverse effects of the Comirnaty vaccine and the Health Ministry has assured the public that the government is committed to continuously monitoring any safety alerts from the current vaccination programme," he said.
Myocarditis is an inflammatory heart disorder induced predominantly by a virus or autoimmune disease. - Bernama