Covid-19: Severe side effects after vaccination highly unlikely, study shows

PETALING JAYA: The benefits of Covid-19 vaccines still outweigh its risks and the rate of severe side effects after vaccination is considered low, according to a Health Ministry study.

Health director-general Tan Sri Dr Noor Hisham Abdullah said this is based on an interim analysis from February to September last year on 433,674 individuals who received at least one vaccine dose and were admitted into hospital for adverse events of special interest (AESI).

Such AESI, which was the focus of the study, were of incidents such as low platelet levels (thrombocytopenia), blood clots in the veins (venous thromboembolism), stroke, heart attack (myocardial infarction), epilepsy and Bell’s Palsy.

“The results of the interim analysis show that AESI incidents, which rarely happen, are different according to the Covid-19 vaccine, first and second dose, age group and gender of the vaccine recipient.

“Nevertheless, the rate of such AESI after vaccination is rather low,” Dr Noor Hisham said in a statement on his blog on Saturday (Jan 22).

The ongoing study, from Feb 2021 to Dec this year, was conducted by the Institute For Clinical Research (ICR) under the National Institute of Health (NIH).

Known as SafeCovac, the study is on case-based monitoring of adverse events following Covid-19 vaccination.

The research involves recipients of vaccines including Comirnaty (Pfizer), Vaxzevria (AstraZeneca) and CoronaVac (Sinovac).

“The study has concluded that the benefits of Covid-19 vaccines still surpasses the risks and for now, the SafeCovac team is analysing interim data to be published.

“Its results will be shared with the public soon,” Dr Noor Hisham added.

He said the ministry would always monitor the safety of all Covid-19 vaccines given conditional approval in Malaysia to ensure the health and safety of the people.

“If there is any clear evidence that the vaccines are not safe, the ministry will not hesitate to take the necessary action,” he said.

He also urged the public to be careful when reading and spreading fake news, especially those from unreliable sources, including about the booster dose programme.

Meanwhile, a total of 984 out of 24,411 reports received on adverse events following immunisation (AEFI) cases up to Jan 20 are related to Covid-19 booster shots.

Dr Noor Hisham Abdullah said of the total 984 cases of AEFI from booster shots, 51 (5.2%) are serious, which is a rate of 0.005 reports for every 1,000 doses.

“The rate of AEFI reports for booster doses are recorded to be 0.1 for every 1,000 doses, compared to the overall AEFI rate of 0.4 for every 1,000 doses.

“Fever, soreness at the injection site, headache and tiredness are among the most frequently reported adverse effects by vaccine recipients,” he said.

Dr Noor Hisham added that there is no increase in AEFI reports involving booster shots compared to the first dose.

“The same trend is also seen in other countries that have carried out booster vaccination programmes,” he said.