The Health Ministry (MOH) today refuted allegations that data about Covid-19 immunisation side effects were manipulated to cover up the real situation from the public.
Health deputy director-general Dr Hishamshah Mohd Ibrahim said that such a thing would not be possible as every adverse event following immunisation (AEFI) case goes through hospitals and their data is captured in official reports.
"How are we going to hide this information? The cases already came into hospitals, captured in hospital data and then they get reported to MOH.
"There is no such thing as hiding reports about vaccine side effects and such.
"We cannot create data that does not exist. And the data that we reported are the data provided by hospitals," he told reporters in a MOH engagement session with the media this afternoon.
Hishamshah was responding to a request for MOH to address public concerns about getting the Covid-19 vaccine booster dose following rumours that many had suffered AEFI, including serious ones.
The ministry has provided AEFI data to the public from time to time but it has been accused of manipulating the information to misrepresent the real situation.
Hishamshah stressed that the ministry is also bound by the law to report every case of medication side effects, including from vaccines and other registered medical products.
As of January 31, the National Pharmaceutical Regulatory Agency (NPRA) has received a total of 23,011 reports of non-serious AEFI cases across the three main vaccines - Pfizer, Sinovac and AstraZeneca - used in the National Covid-19 Immunisation Programme. The figure includes reports from incidents that happened after primary doses and boosters.
For serious AEFI cases, NPRA received a total of 1,729 reports as of the same date.
However, according to NPRA director Dr Roshayati Mohamad Sani, only 8 percent of the serious AEFI cases reported were found to have direct causal link with Covid-19 vaccines.
While there had been vaccine recipients who died not long after receiving their jab, so far none were found to be directly linked to vaccination.
Detailed investigations
During the engagement session, Roshayati also elaborated about the process of determining whether a side effect was caused by vaccination or otherwise.
She said that when a medical facility receives an AEFI case, they will conduct the investigation first.
"Once they are done, then the report would be submitted to us for evaluation. This is when we, a group of experts including special pharmacovigilance specialists, cardiologists and others would confer.
"We will discuss in detail the findings made by specialists from the respective facilities, and evaluate if an adverse event has a link to the vaccine or not.
"Then we will use a standard algorithm as advised by the World Health Organisation to determine causal link," she said.
Among the information that is looked into include clinical data provided by the hospital, patient's medical history, blood sample analysis, X-Ray, and in the case of death, the post-mortem report.
According to the doctors, they have encountered cases where vaccine recipients suffered complications from pre-existing medical conditions but it was blamed on vaccination.
"Recently, there were several cases reported by the media about vaccine recipients who died several days after receiving their vaccine shots.
"However, after a post-mortem was conducted, it was found that they had existing medical conditions.
"There was also a case where the patient claimed he developed 'bisul' (abscess) due to a vaccine. But medical history revealed that he has had it before this," said Hishamshah.
No safety signals detected
Meanwhile, active monitoring for vaccine side effects by the Institute for Clinical Research also found the rates for certain severe AEFI to be low, sometimes even below pre-pandemic rates.
“Our data shows that for now, the safety of Covid-19 vaccines is assured. Compared to the available baseline rates, vaccination did not cause a safety signal,” said Norazida Rahman who led the study.
Unlike NPRA’s monitoring, the institute’s Safecovac study doesn’t not rely on doctors and patients to report what they suspect to be AEFI.
Instead, it monitors adverse events of special interest (AESI) in admission data from public and private hospitals nationwide and links it to vaccination records, especially for admissions that occur within 21 days after vaccination.
However, it does not conduct in-depth analysis like the NPRA to establish causality.
According to Norazida, the rate of ischaemic stroke was between 33 to 150 per million persons vaccinated with the Pfizer, Sinovac, or AstraZeneca vaccines.
This is far lower than the background rate of 600 to 800 per million hospital admissions for the condition in 2016.
Likewise, there are 28 to 91 hospital admissions for myocardial infarction (heart attacks) per million people vaccinated with these vaccines. In contrast, the MOH hospitals had discharged 625 myocardial infarction patients per million population in 2017 and 829 patients per million population in 2018.
Comparing the rates of hospital admission for stroke or heart attacks that occur within 21 days after Covid-19 vaccination, versus the rates before or after that period, also found no significant difference.
The other conditions monitored by the Safecovac study are myocarditis and pericarditis (inflammation of certain parts of the heart), thrombocytopenia (low platelet count in the blood that increases the risk of bleeding), and Bell’s palsy (a short-term facial paralysis).
Benefits outweigh risks
Norazida said that within 21 days of vaccination, there are 1.2 hospitalisations for myocarditis/pericarditis per million persons vaccinated with either the Pfizer or Sinovac vaccines.
For those aged 40 to 59, the rate is 2.9 cases per million persons for the Pfizer vaccine and 0.3 cases per million for the Sinovac vaccine.
For thrombocytopenia, there were 14 cases per million people following vaccination with the Pfizer vaccine, and 6 cases per million each for the Sinovac and AstraZeneca vaccines.
However, Norazida noted that a laboratory report is needed to determine whether the thrombocytopenia cases were vaccine-related, which was not done for the study.
As for Bell’s Palsy, Norazida said the rate within 21 days after vaccination is 3.1 per million people for the Pfizer vaccine, 2.2 per million for the Sinovac vaccine, and 2.5 per million for the AstraZeneca vaccine.
Although Hong Kong authorities have flagged a potential safety signal linking the Sinovac vaccine to Bell’s palsy, she said the Safecovac study thus far found the numbers to be very low and not associated with vaccination.
The interim analysis is based on data collected from Feb 1 to Sept 30 last year, which she said would cover half of the Malaysian population vaccinated that year. Monitoring is still ongoing.
Meanwhile, Hishamshah noted that the rate of myocarditis associated with Covid-19 infection is some 450 times higher than vaccination.
“That’s why when we compare the risk versus benefit, the benefits of vaccination are so much higher.
“We're not saying that there are no side effects. We know side effects are there with vaccination because we have been giving vaccination since Merdeka. So that’s something we’re constantly monitoring,” he said. - Mkini
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