SINGAPORE, Sept 17 — As of Aug 31, there were a total of 90 reports of suspected “adverse events”, including five serious ones, experienced by individuals who went to get the Sinovac-CoronaVac vaccine.

The Health Sciences Authority said in its fifth safety report on Thursday (Sept 16) that the 90 reports were out of a total of 168,439 doses of the vaccine being administered here since June 18 when the first dose was given.

An adverse event for vaccination is any undesirable medical condition that occurs after taking the vaccine, which does not necessarily have a direct link to it. It may be coincidental or related to an underlying or undiagnosed disease.

These have to be reported by healthcare providers to HSA.

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The 90 reports are a jump from the 47 suspected adverse events cited in HSA's fourth safety report about a month ago — a 91.5 per cent increase.

This is a higher rate of increase than the number of Sinovac-CoronaVac doses, which went up by 61.9 per cent (from 104,061 doses as of July 31 to 168,439 doses as of Aug 31). 

The five serious suspected adverse events for Sinovac-CoronaVac included one report of Bell’s palsy, one of serious allergic reaction and vertigo with ringing of the ears, and two reports of anaphylaxis (a serious or life-threatening allergic reaction). 

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Safety update for mRNA vaccines

As for the messenger ribonucleic acid (mRNA) vaccines from Pfizer-BioNTech and Moderna, which are part of Singapore’s national voluntary vaccination programme, HSA said that it has received 11,737 reports of suspected adverse events. 

This is 0.13 per cent of the more than 8.7 million doses administered as of Aug 31, just marginally more than the 0.12 per cent in the last update last month.

About 80 per cent of the suspected adverse events were among people younger than 60, and 67 per cent were women. 

 

For serious suspected adverse events, these made up 498 or 0.006 per cent of all doses of the mRNA vaccines. This is also marginally higher than the 0.005 per cent in the last update. 

Reactions in children aged 12 and older

Among children between 12 and 18 years old who took the mRNA vaccines, HSA received 491 reports of suspected adverse events, which makes up 0.08 per cent of the doses administered to them since June 3. 

This is the same as the 0.08 per cent reported in the previous safety update.

There were 26 reports from this age group displaying who fainted, just one more than the 25 last month. 

The rate of syncope — the medical term for fainting or passing out — in this age group here is about 4.5 per 100,000 doses, which is similar to the rate from overseas reports.

Source: Singapore Health Sciences Authority
Source: Singapore Health Sciences Authority

It is lower than the 5.1 per 100,000 cases in last month’s report. 

HSA said that syncope is generally triggered by the vaccination process, such as anxiety about the injection and fear of pain, and not by the vaccines.

Reactions in serious cases  

Out of the 498 serious suspected adverse events related to the mRNA vaccines, the most frequently reported reactions were anaphylaxis and other severe allergic reactions. 

·      Anaphylaxis: 72 reports with an incident rate of 0.87 per 1,000,000 doses administered (compared to 58 reports with an incidence rate of 0.86 in the previous report) 

·      Myocarditis and pericarditis, which are inflammatory conditions in the heart: 65 reports compared to 34 last month

·      Cerebral venous thrombosis, a rare type of stroke: 10 cases compared to nine last month

·      Bell’s palsy, which is weakness or paralysis in facial muscles: 96 cases with an estimated local incidence rate of 2.4 per 100,000 individuals a month (compared to 76 cases with an estimated local incidence rate of 1.8 per 100,000 individuals a month) — TODAY

Source: Singapore Health Sciences Authority
Source: Singapore Health Sciences Authority