KUALA LUMPUR: The Health Ministry has detected a total of 25 cases of myocarditis (inflammation of the heart muscle) among vaccinees within 21 days of receiving their Covid-19 vaccine jabs.
Of the total, 14 cases of myocarditis were linked to Pfizer-BioNTech Covid-19 vaccine (Comirnaty) recipients, while the remaining nine were identified among Sinovac (CoronaVac) recipients and two were AstraZeneca vaccine recipients.
The findings, it said were based on a vaccine safety study in Malaysia conducted by the Institute of Clinical Research (ICR), National Institute of Health (NIH), and the health ministry following an analysis of 433,674 admissions to 216 public and private hospitals.
The ministry said the study, known as the Case-Based Monitoring of Adverse Events Following Covid-19 Vaccination (Safecovac) found that the actual incidence rate of myocarditis per million doses given was 0.9 for Comirnaty recipients, 0.5 for CoronaVac and 0.7 for the Astra Zeneca.
"Among those under 30 years of age, the actual incidence rate of myocarditis was 0.87 per million doses given for Comirnaty and 0.49 for CoronaVac.
"Whereas, for individuals aged 30 years old and above, the actual rate of myocarditis is 1.0 per million doses for Comirnaty and 0.6 for CoronaVac.
"The Safecovac study showed no significant link based on the relative incidence rate of myocarditis during the observation period for all vaccine and age groups.
"The findings of this study are consistent with the continuous Adverse Event Following Immunisation (AEFI) pharmacovigilance system by the National Pharmaceutical Regulatory Division (NPRA), which reported a myocarditis rate of 1.5 incidents per million doses (0.5 incidence per million doses for ages 18 and older, 0.9 incidence per million doses for ages under 18)."
The ministry, therefore, conclusively said results from Safecovac, data from the AEFI NPRA system and Real-World Data (from the Real-World Evaluation of Covid-19 Vaccines Under the Malaysia NIP (RECoVaM) point towards "a very rare incidence of myocarditis" after receiving Comirnaty vaccination when compared to a higher risk of getting myocarditis from Covid-19 infection.
Further, it said the vast majority of reported cases of myocarditis were mild, self-limited, and capable of immediate cure.
The health ministry said this in a statement today amid concerns of AEFI and incidents of myocarditis and pericarditis, particularly concerning Covid-19 mRNA vaccine (Comirnaty) for the country's adolescent population.
It noted that with over 33 million doses of mRNA-based vaccines monitored in the country, the NPRA did not detect any "Safety Alert" to prove the adverse effects of the Comirnaty vaccine.
The NPRA, it said, conducts rigorous assessments to ensure the quality, safety and effectiveness of Covid-19 vaccines meet the Regulatory Standards.
"We assure that the government is committed to continue monitoring any safety warning signs throughout this vaccination programme."
"Myocarditis is an inflammatory disease of the heart muscle and is usually caused by a virus or autoimmune disease.
"In June 2021, the United States Centres for Disease Control and Prevention (CDC) reported that the risk of myocarditis in children under the age of 16 was 37 times higher for those infected with Covid-19 than for those not yet infected with the virus.
"Furthermore, a study in Denmark involving 3.5 million recipients of the Comirnaty vaccine reported that the actual risk of myocarditis after vaccination among those aged 12-39 years is 1.6 per 100,000 while for those aged 12-17 years, it is 1.0 per 100,000.
"Based on the rare risk of myocarditis after vaccination, the study team supported the overall benefits of Covid-19 vaccination to individuals globally."
The ministry said based on comprehensive scientific evidence and data, it would continue its efforts and recommendations on the Covid-19 immunisation programme.
Meanwhile, it said the RECoVaM study found that the case rate of Covid-19 infection per 1,000 population among the unvaccinated group was significantly higher at 36.2 compared to Astra Zeneca (7.1), Pfizer-BioNtech (6.6) and Sinovac (11.6) vaccine recipients.
"During the observation period from April 1, 2021 to Jan 9, 2022, Malaysia reported 2,440,873 cases of Covid-19 infection.
"This includes 628,627 cases that have been reported to occur among individuals under 20, and of that number 331,991 cases are among men."
As of Jan 2022, it said 80 per cent of the population in Malaysia have been fully vaccinated.
However, it said studies around the world, including in Malaysia, have shown a decrease in the level of immunity among vaccine recipients after several months of receiving a complete dose.
"Therefore, the Covid-19 Immunisation Special Task Force recommended the booster dose administration programme for all to be implemented in stages."
In addition, it said the Drug Control Authority (DCA) had recently given conditional approval to the Comirnaty Vaccine 10mcg Concentrate for Dispersion for Injection for children aged 5 to 11 years old.