Saturday, 9 January 2021

Is the COVID-19 Vaccine safe for me?

More frequent tests, additional requirements likely for those who do not take COVID-19 vaccine: Lawrence Wong
By Ang Hwee Min, Channel NewsAsia, 8 Jan 2021

Individuals who choose not to take the COVID-19 vaccine may need to go through “more frequent testing”, said Minister for Education Lawrence Wong on Thursday (Jan 7). 

In an interview on CNA’s Talking Point, the co-chair of the COVID-19 multi-ministry task force spoke of "tangible benefits" for those who choose to get vaccine shots.

“It may well be, if the data validates all the hypotheses, that transmission risk can be significantly reduced. It may well be that travellers coming back need not serve SHN (stay-home notice) or will serve a shorter SHN. So those will be the benefits of getting a vaccination besides the fact that you are protecting yourself and your loved ones,” he added. 

“There will be these tangible benefits and those who choose not to be vaccinated, well, then you have to live with more frequent tests, you have to live with quarantine, you have to live with all of these other additional requirements.”


Mr Wong also explained why the vaccine made by the Chinese biopharmaceutical company Sinovac was picked as one of the three vaccines to be used in Singapore.

The vaccine is 78 per cent effective in protecting against the coronavirus, according to the results of a study announced on Thursday by Brazilian state health officials. More than 12,000 health workers in Brazil participated in the study.

The Government convened an expert panel to look at making early purchases of vaccines “as early as April”, Mr Wong said.

“We have to make early bets in order for Singapore to be near the front of the queue for vaccines. And that's what is happening today.”

At the time, there was no clinical data or “full-fledged information” available from any vaccine company, said Mr Wong.

With only "very early stage clinical information" available, the committee and experts narrowed down the selections to 35 vaccine candidates. They eventually decided on the three vaccines - Moderna, Pfizer-BioNTech and Sinovac - based on safety and effectiveness based on the preliminary data that was available then, he added.

“And that's the three that we have made advanced purchases for, with the aim of building a diversified portfolio of vaccines that will be safe and effective for use in Singapore,” said Mr Wong.

When asked by Talking Point host Steve Chia if this approach by Singapore could be characterised as "hedging (its) chances", Mr Wong replied: "Very much so."

According to the Economic Development Board (EDB), the vaccine panel made its first advance purchase agreement with Moderna in June, securing it with a downpayment. In August, it bought the Sinovac vaccine and was in advance talks with Pfizer-BioNTech.

Singapore’s Health Sciences Authority (HSA) eventually approved the Pfizer-BioNTech vaccine first. Prime Minister Lee Hsien Loong announced in a televised address on Dec 15, 2020 that the first shipment would arrive by the end of December, with other vaccines expected in the coming months. 

The panel intends to continue to see whether it can make further purchases to add to the vaccine portfolio, said Mr Wong.

“That's our overall approach. It's not to make a single bet, we know that we've made some early bets, some may turn out positive as I think Pfizer has now been authorised, Moderna looks like it's going to be, it has been approved in America,” he added.

“We are looking at the data, we will await that data full data from Sinovac and then the process will continue for other vaccine candidates.”


The Moderna and Pfizer-BioNTech vaccines use the new messenger RNA (mRNA) technology, while Sinovac is a traditional inactivated virus vaccine.

mRNA vaccines teach our cells to make a protein that triggers an immune response inside our bodies, said director of communicable diseases at the Ministry of Health (MOH) Associate Professor Vernon Lee. This is different from traditional vaccines that put a weakened or inactivated germ into our bodies.

“This is basically the key - the actual mRNA degrades very quickly in the body, so body temperature will only remain for about 48 hours. And thereafter, there's no additional component of the vaccine that remains in the individual,” added Assoc Prof Lee, who was also speaking on Talking Point.

Although the Pfizer-BioNTech vaccine is the only one approved so far, as additional vaccines come onboard, there will be some vaccines that can or cannot be used in certain subpopulations, he added.

For example, the Pfizer-BioNTech vaccine cannot be used in people who have severe allergic reactions or a history of anaphylaxis, said Assoc Prof Lee. For now, children under 16, pregnant women and individuals who are severely immunocompromised are also excluded from using the Pfizer-BioNTech vaccine.

“Other vaccines might be able to be used in different populations. So we need to wait for more information, and it is which vaccine is more ... applicable or relevant to that particular population if it's offered, we will encourage people to get that vaccine,” he added.

The third guest on Talking Point, Associate Professor Benjamin Ong, senior vice president (Health Education & Resources) at the National University of Singapore (NUS), said the data for the Pfizer-BioNTech vaccine is “most complete”, and experts are “confident enough” to recommend its use in Singapore’s setting.


On the subject of whether people would be allowed to choose their vaccine, Mr Wong said that the Pfizer-BioNTech and Moderna vaccines worked similarly, and efficacy rates from evidence around the world were “all about the same”.

“So really, there's not much to differentiate between these two vaccines. I think at this point in time, we have Pfizer only, there's nothing to choose from. So let's go with Pfizer, get people vaccinated on the Pfizer vaccine,” he added.

“If later on other vaccines are authorised, be it Moderna or Sinovac, then we have to think about whether choice may be extended. Or perhaps some vaccines work better for certain sub-segments of the population, and then we might allocate vaccines differently as well.”


When asked about the new strain of COVID-19 that surfaced after the Pfizer-BioNTech and Moderna vaccines were approved around the world, Assoc Profs Ong and Lee said mutations occur “all the time”, and are part of "natural evolution”.

Prof Lee likened the mutations to a car getting a different licence plate or colour.

“The same make, same model, different licence plate, we see many of them all around the time. And sometimes you might have a car with new tires, it might be a bit more efficient, move faster, and so on, but it's still the same make,” he added.

“At this point, there's no evidence that it (the virus) has changed to another make, another model, another brand. And we, of course, will be looking out for different strains, different variants that occur all the time.”

From the mutations that have been studied so far, it seems like the vaccines “probably would still work”, said Assoc Prof Ong, adding that this is being actively tested.

“The areas that pertain to the spike protein, for example, are conserved. So from the basic scientific principles, it should still work. And we will know very soon because more than two, three million people now in the UK in the US have received a vaccine. And if it is not going to work, in the next few weeks to months, we will know,” he said.

The variants that have been reported are only those that have been detected, and there may be others that have yet to surface, said Assoc Prof Lee.

“Actually what's important is in addition to the vaccine, we have a very strong border, you know, control regime, plus all the same management measures wearing of masks or contact tracing,” he added.


Acknowledging that many people hope to return to a pre-pandemic normal, Mr Wong said that even in a post-COVID-19 world, there would be pandemics with more virulent diseases that arise in the future. 

“I think rather than thinking about let’s go back to life before COVID, I think we should be thinking now about what are the things that we have done during this period that really ought to be permanently part of our new daily routines,” he added.

“And how can we raise our levels of defences, our levels of protection, our levels of hygiene so that we can be more prepared and more resilient in the future?”

Assoc Prof Lee also stressed that individuals who do not get vaccinated are “still susceptible” to being infected with COVID-19.

“Even if we reach that sort of herd immunity or collective protection level, it does not mean that there will be no cases and that’s the same for all other infectious diseases. And the risk of cases occurring in Singapore is not just what we do here but what’s happening in the rest of the world,” he said, adding that an open economy, travel and trade would result in imported cases.

“If we are not vaccinated, every single individual who is not vaccinated, is another naive susceptible individual who then can get infected by those diseases. To protect yourself, you should get vaccinated and then there’s the other benefit of protecting your loved ones and those around you,” said Assoc Prof Lee.

“It is very important for that reason because even if we have a high vaccination coverage, it does not mean no disease. It is not possible to wipe COVID-19 from the face of the earth. We’re going to see this recurring from time to time, so it is important for that personal protection reason.”

COVID-19 vaccine could mean shorter stay-home notice for those who take it: Lawrence Wong
Govt will consider it if data shows vaccination significantly reduces the transmission risks
By Rei Kurohi, The Straits Times, 9 Jan 2021

Travellers who have been vaccinated against Covid-19 may avoid having to serve a lengthy stay-home notice (SHN) when they return to Singapore in the future, Education Minister Lawrence Wong has suggested.

Mr Wong, who co-chairs the multi-ministry coronavirus task force, said the Government would consider drastically reducing or even doing away with the two-week quarantine requirement if data shows vaccination significantly reduces transmission risks.

He said this was one of the potential "tangible benefits" for those choosing to be vaccinated, besides protection against the virus. "Those who choose not to be vaccinated, you have to live with more frequent tests, you have to live with quarantine, you have to live with all of these other additional requirements," he said on Thursday in an interview on CNA's Talking Point.

"If you have the vaccination, you travel to a high-risk place, you come back, can that SHN be shortened, or even done away with completely? That is the big question," said Mr Wong. "We still don't know the extent to which a vaccination can completely - or how significantly - help reduce transmission risk. So, those studies are still pending. If indeed the data shows that transmission risks can come down significantly with vaccination, then certainly, we will consider reducing drastically the SHN or even doing away with it."

Being vaccinated may also make it possible to travel abroad more freely, depending on the requirements in other countries, Mr Wong noted. "Even without a vaccine today, many Singaporeans can already travel freely to other countries without a quarantine there because they regard Singaporeans as coming from a low-risk jurisdiction," said the minister.

"I think with a vaccination, it will certainly help, but those are regulations that are outside of our control."

The discussion, hosted by CNA presenter Steven Chia, also featured Associate Professor Vernon Lee, director of the communicable diseases division at the Ministry of Health, and Associate Professor Benjamin Ong, who chairs the expert committee on Covid-19 vaccination convened by the MOH.

Prof Lee debunked a number of rumours about the vaccine, including one that it can cause cancer.

"At this point, there is no evidence that this vaccine will result in such a side effect," he said in response to a question from a viewer. He added that most of the known side effects are mild, but the vaccine can cause severe allergic reactions in some people. The messenger RNA used in the Pfizer-BioNTech vaccine, currently the only one being administered here, also does not incorporate itself into human DNA, Prof Lee noted. "In fact, after about 48 hours, it just dissipates in the body and it disintegrates, so there is no evidence at this point that there is any such concern," he said of the cancer rumour.

There is also no evidence that a patient who receives the vaccine will have difficulty getting pregnant, Prof Lee said in response to another question.

Prof Ong said the likelihood that the vaccine will cause long-term issues is "very remote". Nonetheless, he said the expert committee decided to play it safe and has recommended pregnant women should wait until after they have given birth before being vaccinated.

Asked about the new strain of the virus that has emerged in Britain and spread to various countries, including Singapore, Prof Ong said mutations occur all the time, adding that the vaccine is likely to still work on the new strain. This is because the mutated virus features the same spike protein as the earlier strain.

Singapore has also purchased a vaccine developed by US pharmaceutical firm Moderna, which similarly uses mRNA technology to introduce the genetic code to the body to produce a piece of the coronavirus known as a spike protein, thereby helping the patient's cells recognise and develop an immune response to Covid-19. The Republic has also bought stocks of a more traditional inactivated virus vaccine produced by China's Sinovac.

Mr Wong said Singapore had to make "early bets" on these vaccines as long ago as last April, before there was extensive clinical data on their efficacy, to ensure Singapore would be near the front of the queue.

Coronavirus After-effects: 3 in 4 COVID-19 patients suffer from at least one symptom six months after infection
Research shows fatigue was most common post-infection problem among 1,733 patients
By Salma Khalik, Senior Health Correspondent, The Straits Times, 13 Jan 2021

Three out of four patients still suffered from at least one symptom six months after falling sick with Covid-19, with the most common problem being fatigue or muscle weakness, a study has found.

Other common post-infection problems were sleep difficulties, and anxiety or depression. More women than men were affected.

These results from the study of 1,733 patients with a mean age of 57 from Jin Yin-tan Hospital in Wuhan, China - the largest such study carried out to date - were published in The Lancet journal last week.

The cohort comes from the 2,469 Covid-19 patients discharged from the hospital between January and May last year. The follow-up was done from June to September, with 736 patients excluded because they did not attend follow-up appointments for various reasons, including dementia.

There were also 33 people who "died after discharge mainly due to exacerbation of underlying pulmonary, heart and kidney disease".

The study found that more than half the patients had "residual chest imaging abnormalities" six months after their illness, with greater impairment in those who had been more severely sick.

About one in four was not able to walk the same distance in six minutes that they were able to before getting Covid-19.

The study said a limitation to this finding is that it was self-reported.

It added that some patients had persistent problems with their kidney function.

In the six months since getting infected, some developed diabetes, or had blood clots that affected their heart or brain.

It noted that some of the continuing problems reflect those suffered by patients who survived Sars, or severe acute respiratory syndrome, in 2003 - which was also caused by a coronavirus.

Researchers in Canada - which had 250 Sars infections and 38 deaths - found that a third of Sars survivors complained of poorer mental health a year after infection, and 40 per cent had chronic fatigue for a mean period of 41.3 months.

A commentary in The Lancet on the China study said: "Evidence from previous coronavirus outbreaks suggests that some degree of lung damage could persist, as shown in patients who recovered from Sars, 38 per cent of whom had reduced lung diffusion capacity 15 years after infection."

Dr Asok Kurup, who chairs the Academy of Medicine's Chapter of Infectious Disease Physicians, said such a long "tail" following severe infection is known to occur - although it is not common.

He said: "Severe influenza, especially in those who end up with respiratory failure, can be followed by respiratory issues that can take a long time to recover from.

"Some types of adenoviruses can occasionally cause both respiratory and even kidney failure, and we have seen some cases needing years to recover."

He added that doctors in Singapore "are seeing some patients who have recovered from Covid-19, but are having respiratory issues".

Professor Dale Fisher, a senior infectious diseases consultant at the National University Hospital, said: "I believe that 'long Covid' exists but it's hard to accredit the symptoms fully to Covid-19 specifically without more research."

He said that anxiety and depression, as well as sleep disturbance, are more common today even in people without Covid-19, but "objective features such as radiological changes in the chest and a deterioration in kidney function are hard to dispute. But what they mean in the longer term is still unknown".

He added: "I don't know why people worry more about the vaccine compared to worrying about Covid-19 itself and the risk of long-term effects; fatigue, breathlessness, sleep disturbance, anxiety, depression, kidney impairment and scarred lungs."

How Singapore picked its COVID-19 vaccines
Republic has been cautious, and talks are on for more in case of delays, need for booster shots
By Salma Khalik, Senior Health Correspondent, The Straits Times, 1 Feb 2021

Last June, Singapore sealed its first deal to buy Covid-19 vaccines - before any of the more than 200 vaccine candidates had even started their phase three clinical trials.

It decided not to wait for the trials, and even paid a premium on the price, in order to secure some early stock of vaccines for people here at high risk, such as healthcare workers and the elderly.

That was for the Moderna mRNA vaccine, which has yet to be approved for use here.

Singapore signed two more purchase agreements in August - with Sinovac which produces a traditional vaccine, and PfizerBioNTech which also uses mRNA.

These purchases should provide sufficient vaccines for the entire adult population. But Singapore is buying more.

Dr Benjamin Seet, who chaired the panel that picked the vaccines for Singapore, said several late-stage discussions are still ongoing with a handful of other companies - as part of a contingency plan should there be disruptions in the supply of purchased vaccines, delays in the delivery, or even the need for further booster shots.

Such delays have occurred with both Pfizer and AstraZeneca - which are among the handful of vaccines approved for use in some countries. And earlier this month, fire broke out at Serum Institute, India's largest vaccine facility, although the company said this will not delay production.

Singapore is known for being ultra cautious, so buying more is better, just in case.

Some of these other vaccines might also be more suitable for people who might not react well to the vaccines already purchased.

Dr Seet, who joined the National Healthcare Group (NHG) in January last year as deputy group chief executive officer in charge of education and research, was appointed chairman of the Therapeutics and Vaccines Expert Panel by the Economic Development Board three months later, on April 13.

This was shortly after the flare-up of cases in foreign worker dormitories that led to more than 54,500 infections in this group.

Dr Seet, 56, recalled: "It was around that point (when there was a big jump in cases) that we realised that the impact on Singapore could be more serious."

The decision was made that "as soon an effective vaccine was available, Singapore should get access to it", he said. "We were tasked to make sure that when Singapore needs it, we do have an effective vaccine in a timely manner."

The first vaccines were purchased two months after the panel was set up.

The panel's 18 members were picked for their wide range of expertise, and comprise experts in immunology and basic science, those with clinical experience as well as pharmaceutical company experts with experience in drug development and manufacturing.

Dr Seet himself is eminently qualified. He was executive director of the Biomedical Research Council at the Agency for Science, Technology and Research (A*Star) before joining NHG.

Even so, selecting which vaccines to put money on, early in their development process, involved hard work, a lot of reading up - "thousands and thousands of pages", said Dr Seet - and many cold calls to companies to find out more about their vaccines.

In the early days, the panel cast a wide net to include both conventional as well as novel vaccine technology by proven giants and promising upstarts.

These were vaccines using RNA (not yet used in vaccines), viral vector (as in Ebola vaccine), inactivated virus (as in flu vaccines) and protein sub-units (as in whooping cough vaccine).

He explained: "We realised that we couldn't put all our eggs in one basket. So we wanted some of the old and some of the new. We also looked at it in terms of timeliness. Which ones could come faster."

Even so, the shortlist had more than 40 companies.

Dr Seet said they went on the principle that "the betting average was probably about one in 10" of the vaccine candidates would make it to market.

He said "the first to the gate, we want some of that", but the team also realised that the first may not be the best. So they picked some that were likely to be fast, and some they thought would be good.

"What surprised us is that the first, indeed, could also be the best in the class," he said, referring to the 95 per cent efficacy shown by the mRNA vaccines from Moderna and Pfizer-BioNTech.

But they did not know that when they made the down payment for advance purchases of these two vaccines last year.

To decide which to put Singapore's money on, the team needed access to still confidential data to assess the potential of the various vaccine candidates.

They drew on Singapore's global network - through the Economic Development Board and Temasek's contacts as well as contacts from the scientific and medical community - to get to someone senior in those companies.

These people were in high demand. But they managed to approach, for example, Moderna's founder, Professor Robert Langer, through one of his former postdoctoral students, a returned Singaporean scholar.

Dr Seet said once they identified the right people in the company, they would make an introductory call "to say we're interested in your vaccine, we might want to consider buying it".

Buying a vaccine that may never make it to the market was a new concept for most pharmaceutical companies, he said.

"The drug industry is probably the most regulated industry. And drug companies will sell only drugs that are fully approved."

But most of the 40-plus companies agreed. After signing non-disclosure agreements, the panel managed to talk to "the elites of the projects" such as the chief medical officers, scientists and the people who did pre-trial tests and those who ran the clinical trials.

Where necessary, colleagues from Singapore's regulator, the Health Sciences Authority, visited the production plants to check on the quality of their processes.

With the agreements, he said "it allowed us to actually have access to data before they were published".

The agreements were legal and lengthy and had to be approved by teams of lawyers from both sides, and detail how the confidential information had to be handled, who had access, and even the legal jurisdiction should there be a breach.

It usually takes up to two weeks for such an agreement, though the fastest was signed in just one day.

"As more data became available, decisions were regularly updated and refined, with new candidates added or taken off the list," he said.

By July last year, the team had narrowed the number of vaccines of interest to just over 20. This was brought down to 12 to 14 by September.

Some, such as vaccines by Merck and Australia's CSL, were discontinued by the developers.

When Singapore placed a deposit with Moderna in June, the vaccine had just entered early stage human trials. The other two purchases were also made before trial results were out.

Dr Seet said that before any decision was made, his team went "very deep into the science".

"We looked at how well-designed the pre-clinical studies were. Some gave us a lot of confidence. Some, we were a bit more wary of.

"We looked at the early data in mice, hamsters, ferrets, and for some, in primates. We looked at how strong the immune response was. We looked at different immune markers, antibody levels, T cell activity.

"We were very keen on the challenge studies where they vaccinate the animals, then expose them to the live virus to see how many actually get infected."

The team also looked at how the vaccine would be delivered. Most Covid-19 vaccines have to be reconstituted, but the panel decided against those that come as three components.

The Pfizer vaccine that Singapore is using today has to be brought in and stored at minus 70 deg C - which was not a problem for Singapore.

It comes in powder form and has to be reconstituted with 1.8 ml of saline solution injected through the vial's rubber cap. Each vial with six doses has to be shaken 10 times before use.

An advance purchase agreement involves several payments as milestones are reached. Should the vaccine not pan out in the end, all the money paid out goes down the drain.

On the other hand, should it prove successful, then Singapore is assured of getting some of the vaccines early.

Since deliveries are usually spread over six months or more, buying from different companies ensured an early first batch and a steady flow of vaccines.

By the end of last year, the first batch of the Pfizer-BioNTech vaccine was already in Singapore. By now, more than 100,000 people have been vaccinated.

The vaccination drive is gathering pace. The groundwork for that was laid almost a year back.

*  Benefits of jab outweigh risks - 4 who had severe allergic reactions from COVID-19 vaccine have recovered, none needed ICU support
By Fabian Koh, The Straits Times, 2 Feb 2021

There were four people who experienced a rapid onset of severe allergic reactions after receiving their Covid-19 shots, but all have recovered, with none needing intensive care unit (ICU) support.

Responding in Parliament yesterday to questions from several MPs about the supply and side effects of the vaccines, Senior Minister of State for Health Janil Puthucheary provided this update about the four people and said the benefits of getting vaccinated outweigh the risks.

Singapore's Covid-19 vaccination drive began on Dec 30 last year. So far, front-liners such as medical workers and aviation and maritime sector workers, as well as the elderly, have started receiving their Pfizer-BioNTech jabs.

Dr Janil told the House that among those who have been vaccinated so far, there were four reported cases of anaphylaxis, which is the rapid onset of severe allergic reactions. They were all in their 20s and 30s, and developed multiple symptoms such as rash, breathlessness, lip swelling, throat tightness and giddiness.

"Three of the individuals had a history of allergies, including allergic rhinitis and food allergy, such as to shellfish, but none had a history of anaphylaxis, which would have precluded them from receiving the vaccine in the first place," he said.

The vaccine is currently not recommended for pregnant women and immuno-compromised people.

Dr Janil said: "As with other vaccines, people who receive the Covid-19 vaccine may experience injection site pain and swelling, fever, headache, fatigue and body aches. These mild symptoms generally resolve within a few days."

He said that anaphylaxis can be controlled when detected and treated in a timely manner, as in the case of the four people.

"All have recovered from the episode. One was under observation for a few hours, while the others were discharged from the hospital after a day's observation or treatment. None needed ICU support," said Dr Janil.

Singapore's incidence rate of anaphylaxis is about 2.6 per 100,000 vaccine doses administered, compared with the incidence rates of around one to two per 100,000 reported in other countries.

These countries have administered millions of vaccine doses, said Dr Janil, and variations in the incidence rate are to be expected initially, with the numbers vaccinated here to date relatively small.

"Currently, the benefits of getting vaccinated to protect oneself from the effects of severe Covid-19 disease and its complications far outweigh the risk of any potential adverse events known to be associated with vaccination," he said.

He said the Government will continue to closely monitor the safety of the vaccine, and ensure that the vaccines used here are safe.

Responding to a supplementary question from Mr Alex Yam (Marsiling-Yew Tee GRC), Dr Janil said that breastfeeding mothers should consult medical professionals, but noted that there is no evidence that getting vaccinated would harm them.

"They should consult a health practitioner, their family doctor or one of the hotlines or service providers, to get specific advice about their case, as to whether or not they should proceed with the vaccine, or delay the vaccine, or delay breastfeeding and have the vaccine immediately," he said.

He added that there is "no absolute contraindication" for a breastfeeding mother to receive her shot.

"It is simply that we don't have enough information at this point to be so clear that they should do it without ceasing breastfeeding for five to seven days," he said.

That same duration is similar to general advice given to breastfeeding mothers who are taking medication, as it is the length of time that the substances remain in breast milk.

He said it is probably better for breastfeeding mothers to get vaccinated, to protect themselves and their families.


**  Health Sciences Authority safety update (30 December 2020 – 18 April 2021)

Serious reactions to COVID-19 vaccinations rare, affecting four in 100,000 out of 2.2 million vaccine doses administered in Singapore
By Joyce Teo, The Straits Times, 7 May 2021

There were 95 serious cases suspected to be reactions to Covid-19 vaccination here over a period of less than four months, and 20 of these involved a potentially life-threatening allergic reaction known as anaphylaxis, the Health Sciences Authority (HSA) said yesterday.

But the 95 cases represent just 0.004 per cent of the more than 2.2 million doses administered from Dec 30 to April 18, the HSA said in its first update on the safety of the mRNA Covid-19 vaccines used here.

About 0.13 per cent of the doses administered resulted in suspected adverse reactions.

About 70 per cent of these cases involved people who were younger than 60 years old, although they made up about half of the people who have taken the vaccines.

There were no deaths associated with taking the vaccine.

There were also no reports of unusual blood clots associated with low platelets that have been reported with other types of Covid-19 vaccines overseas, said the HSA.

It defines an adverse effect as serious when it results in hospitalisation, a significant reduction in functional capacity, a life-threatening event like anaphylaxis, or death.

Most of the adverse events were associated with the Pfizer-BioNTech vaccine because this has been available since Dec 30. The Moderna vaccine was rolled out only on March 12.

Nearly 850,000 people have completed the vaccination regimen by taking two doses as at April 18, according to the Ministry of Health (MOH).

Anaphylaxis, which typically happens very quickly, remained the greatest concern because it is life-threatening, said the HSA.

Within minutes of getting the vaccine, a person who has it may experience swelling of the face, eyes and lips. Their airway can be constricted, and there may be nausea, vomiting and diarrhoea.

The 20 cases were in people aged 23 to 68, and most of them were women. About 55 per cent of them had a history of allergies, to food or drugs. And, 60 per cent of them had onset of symptoms within 30 minutes. All have recovered after medical treatment, said the HSA.

The incidence rate of this reaction here is about 1.4 per 100,000 doses administered, which is similar to the incidence rates reported overseas, of around 0.5 to two per 100,000 doses administered.

Anaphylaxis incidence rate in Singapore similar to those reported overseas

Anaphylaxis is a reaction that has been reported with the use of other vaccines too, as is Bell's Palsy, which the HSA is also monitoring closely.

There have been 25 cases of Bell's Palsy, which is a temporary paralysis of a part of the facial muscles, and most are not serious, it said. Most patients recover completely, even without treatment.

The 25 works out to a rate of 3.45 per 100,000 people per month, which is within the background incidences of 1.1 to 4.4 per 100,000 people per month prior to the introduction of vaccination, said the HSA.

Among the 95 with serious adverse events, 20 involved anaphylaxis, while another 20 had severe allergic reactions, including severe rashes, possible shortness of breath and rapid heartbeat.

Other serious adverse effects include breathing difficulty, fast heart rate, an increase or decrease in blood pressure, chest discomfort, fainting, limb numbness or pain for a few days, changes in vision and an increase in liver enzymes, said the HSA update.

Most of the 95 people have recovered or are recovering.

They are among a bigger group of 2,796 people who experienced adverse effects associated with the vaccine, according to the HSA data.

The most commonly reported adverse effects of getting the vaccine shot are rashes, hives, dizziness, swelling of eyelids, face and lips, fever, shortness of breath, muscle aches, headache and itchy skin, said the HSA.

These effects are in line with the ones described in clinical trials and Covid-19 vaccine product information.

"Based on available data, the benefits of the Pfizer-BioNTech and Moderna Covid-19 vaccines continue to outweigh the known risks in a pandemic," the HSA said.

It will continue to monitor the safety of the vaccines, and release vaccine safety updates on a monthly basis from now on.

No rise in heart attack, stroke cases among vaccinated people: HSA
Also no evidence that vaccines used here can directly cause such medical events, says Health Sciences Authority
By Joyce Teo, The Straits Times, 7 May 2021

There has been no uptick in heart attacks or strokes among vaccinated people, and no evidence that the Covid-19 vaccines used here can directly cause them, the Health Sciences Authority (HSA) said yesterday.

"A greater frequency of heart attacks and strokes has not been observed in vaccinated persons locally and to date, there is also no evidence that the vaccines can directly cause these events," HSA said in its first update on the safety of the mRNA vaccines used here.

Only the Pfizer-BioNTech and Moderna vaccines are used here.

"No deaths from heart attacks, strokes or any other causes suspected to be associated with the vaccines have been reported locally," HSA said. It had looked at the cases of adverse events - there were 2,796 - that arose from the more than 2.2 million doses administered between Dec 30 and April 18.

Due to the large number of people being vaccinated, some may, by chance, experience medical events such as heart attacks and strokes in the days or weeks after vaccination. And this may not be related to the vaccination, said HSA.

At a Ministry of Health (MOH) media briefing yesterday, an HSA spokesman said it is hard to ascribe causality to heart attacks or strokes as they can happen spontaneously and generally these patients do have underlying medical conditions.

Professor Teo Yik Ying, dean of the National University of Singapore's Saw Swee Hock School of Public Health, said at the briefing that typically, in a three-month period, there would be some 2,000 stroke cases and slightly fewer than 3,000 heart attack cases. People can experience these, whether they are vaccinated or not.

"There have not been any established links between cases of stroke or heart attack with either the Pfizer or Moderna vaccines in the United States, which has seen at least 240 million doses delivered as at May 5," he said.

He said vaccination remains key to the battle against Covid-19 as new variants spread and form clusters here. "The signal from the Tan Tock Seng Hospital (TTSH) cluster is that vaccination helps because it provides much better protection against serious outcomes of infection," he said.

MOH's director of medical services Kenneth Mak had earlier said that eight patients in the TTSH cluster who had been vaccinated were either asymptomatic or exhibited very mild symptoms, and none required oxygen therapy.

"Of those not protected by vaccination, seven of the 20 had need of oxygen therapy," he had said at a May 4 Covid-19 press conference.

Yesterday, MOH said it had received and was processing applications for the Vaccine Injury Financial Assistance Programme for Covid-19 vaccination (VIFAP).

Under Vifap, which was launched on March 17, those who need inpatient treatment and medical intervention, and who subsequently recover, will get $2,000.

Those who require admission to high dependency or intensive care wards, and subsequently recover, will get $10,000.

Those who die or suffer permanent severe disability as a result of the vaccination will get $225,000.


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Singapore starts COVID-19 vaccination exercise for seniors on 27 Jan 2021; over 100,000 people have had jab so far

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