COVID-19 Vaccine


What You Need To Know About COVID-19 Vaccine

Getting vaccinated is one of the most crucial steps in protecting yourself and your loved ones from COVID-19. It is also to achieve herd immunity for the greater good. Learn more about COVID-19 types of vaccines, facts, safety, who is eligible, commonly asked questions and more.

At Gleneagles Hospitals, your health and safety are our priorities.

What is the COVID-19 vaccine?

COVID-19 vaccine helps our bodies develop immunity against COVID-19 virus by stimulating our immune system to fight SARSCoV-2 (severe acute respiratory syndrome coronavirus 2) whenever we are exposed to it. 

Various platforms such as RNA genetic sequencing, viral vectors, deactivating viruses and protein sub-units have been used to provide safe and effective coronavirus vaccines. It gives you the best protection against COVID-19. 

The COVID-19 vaccine is regulated and complies with the following Acts:

  • Poisons Act 1952 (Act 366) and its regulations
  • Sale of Drugs Act 1952 (Act 368) and its regulations
  • Drugs and Cosmetic Control Regulations 1984
  • Infectious Disease Prevention and Control Act (Act 342)


What are the types of COVID-19 vaccines?

At the moment, frontrunners in the coronavirus vaccine race include Moderna, Pfizer BioNTech, Sinovac Biotech and Oxford AstraZeneca.

The vaccines protect against symptomatic forms of COVID-19, but it is still unclear whether they will stop the spread of the SARS-CoV-2 virus, the cause of COVID-19. Therefore, you should still continue to take appropriate precautions in protecting yourself and others around you even after receiving the COVID-19 vaccine.

Click for Infographic to know What are the Types of Vaccines

Technology and the COVID-19 vaccine

Both the Moderna and Pfizer BioNTech’s vaccines use mRNA (messenger RNA) technology and it is interesting to note that the mRNA vaccines have never been approved for use in any disease. It has however received emergency use authorization from the FDA. 

mRNA vaccines work by injecting pieces of the virus’ genetic code into the body to stimulate an immune system reaction which enables the body to defend itself against the coronavirus.

The mRNA in the body breaks down fully within 48 hours. As it doesn’t enter the human nucleus, it does not affect human DNA. Both Moderna and Pfizer’s mRNA vaccines require 2 doses for adequate protection, and the doses are administered between 3 and 4 weeks apart.

Oxford AstraZeneca and Sinovac Biotech’s vaccines employ a modified delivery virus (that usually causes symptoms such as the common cold) to introduce SARS-CoV-2 viral proteins to the immune system, which then mounts a defence against it. The delivery virus is attenuated or modified so the person won’t develop the common cold when administered with this vaccine.


Why is COVID-19 vaccination important?

The national COVID-19 immunisation programme by the Malaysian government is an important step to stop the pandemic. Benefits from the immunisation programme include;

  • Preventing someone from COVID-19 infection or becoming seriously ill due to COVID-19.
  • Curb the spread of COVID-19 to others.
  • To achieve herd immunity where a significant amount of the population is protected through vaccination against the virus, making it difficult for the disease to spread. 


Is it safe for those with heart conditions?

Can those with cardiovascular conditions or heart problems take the COVID-19 vaccine?

In short, yes. In fact, heart patients are highly encouraged to take the COVID-19 vaccine as it can help to protect them from contracting the virus. Here’s why.

According to studies, heart patients have a higher risk of developing health complications from COVID-19 compared to those without history of heart problems. That is why, heart patients fall under a group of people who have been prioritized to get the COVID-19 vaccine alongside other patients with chronic diseases such as diabetes, hypertension and high cholesterol etc.

Therefore, if you are an individual that have heart conditions, or if your family member is a heart patient, you should take or advice your family member to get vaccinated against COVID-19 – by taking this action, not only are you protecting yourself but you are also protecting your loved ones from COVID-19.

However, it is understood that you may have some concerns over the safety of the COVID-19 vaccine, especially since you or your loved ones have pre-existing medical conditions. Would it worsen the condition or will the side-effects be more severe?

Will those with cardiovascular disease or heart problems experience any side effects?

The current mRNA COVID-19 vaccines available in the market have been shown to be safe for use for heart patients. This is because people with pre-existing medical conditions such as diabetes, heart problems, hypertension and high cholesterols were included in the early clinical trials. Which means that the vaccines have been tried and tested by people who have the same medical conditions as you and they were found to benefit from the vaccine.

When it comes to side effects, most vaccine can have side effects. It is important to note that both the mRNA vaccines PfizerBioNTech and Moderna do carry the risk of some common side effects such as pain, redness or swelling in the shoulder muscle area where the injections were administered, as well as fatigue, headaches, muscle pain, chills, fever and nausea. These symptoms will most likely resolve within one or two days. If the symptoms persist, please consult a healthcare professional for medical advice.

However, if you history of allergic reaction to any component (active ingredients or excipients or any material used in process) of the vaccine or similar vaccines, it is advisable for you not to get the vaccine – not at least until more safety data become available.

Should you get vaccinated if you have cardiovascular disease or heart problems?

Yes, you should. As advised by Ministry of Health, everyone who is medically eligible should get vaccinated. This is because as more people get vaccinated, the slower the virus would spread, and as a result our community will be safer.

However, if you are still concerned about the safety of these vaccinations, we encouraged you to seek consultation with your doctor. Click here to speak with our doctors. Our doctors will be able to assess your medical and allergy history to determine your eligibility for COVID-19 vaccines.

However, if you still have concerns, you may well get advice from your consultant.


Is it safe for Pregant Women and Breastfeeding Mothers?

Update: Recent announcement by the Ministry of Health, Malaysia on 25 May 2021 indicated that only the Pfizer vaccine is allowed for pregnant women between week 14 and 33, or they should defer vaccination till after their delivery. The AstraZeneca and Sinovac vaccines are not recommended at the moment. As for breastfeeding mothers, both the Pfizer and AstraZeneca vaccines are suitable for them. For Sinovac vaccine, it is currently not recommended for pregnant women due to the limited clinical data. Breastfeeding mothers who would like to opt for Sinovac vaccine are required to consult their specialists prior to vaccination.

Vaccine Pregnant Mothers Lactating Mothers

Source of information: Kementerian Kesihatan Malaysia

Government bodies and health authorities around world are encouraging eligible members of the general public to get vaccinated. This is because as more people get vaccinated it reduces the chances of transmission. Which means it becomes more difficult for the virus to spread, hence making it safer for the society if more people get vaccinated.

But, what if you are pregnant or breastfeeding? Is it (really) safe to get vaccinated for COVID-19?

Is it safe to get vaccinated if you are pregnant?

There is currently very little data available to assess the safety of COVID -19 vaccines on pregnant women and breastfeeding mothers because of the lack of clinical testing during the development of the COVID-19 vaccine. Having said that, based on the safety and efficacy data of the current vaccines in the market, the World Health Organization (WHO) states they do not have any reason to believe there will be specific risks that would outweigh the benefits of vaccination for pregnant women. In fact, findings of a few studies did not indicate any adverse effects on fetal development.

Additionally, pregnant women and breastfeeding mothers have also taken other vaccines such as tetanus toxoid, influenza and pertussis for example. However, If you are still unsure, we highly recommend that you speak to your OB-GYN to seek advice and discuss about your eligibility for COVID -19 vaccination.

Is it safe to get vaccinated if you are breastfeeding?

While there is currently very little data to suggest the safety and efficacy of the COVID -19 vaccines on pregnant women or breastfeeding mothers, there are also no known risks of the COVID-19 vaccine to breastfeeding mothers.

This is because the vaccines currently available in the market are non-replicating vaccines. Non-replicating vaccines can create an immune response but do not reproduce inside host cells – meaning that there is no possible way by which the vaccine can pass to your baby through breast milk.

So, is it (really) safe for pregnant women and breastfeeding mother to be vaccinated?

  • It is encouraged for pregnant woman and breastfeeding mother to consider getting vaccinated against COVID -19 especially if you are in the frontline e.g. a healthcare worker or have known medical conditions. However, the decision should be made as a mutual agreement between the mother and her consultant. She should get clearance from her consultant prior to considering getting vaccinated for COVID-19.
  • Despite insufficient data on the potential effects of the Covid-19 vaccines in expecting and nursing mothers, the Health Ministry will allow them to be inoculated if the benefits outweigh the risks. However, the decision to either allow or advise these mothers against receiving their vaccine shots must come from a specialist after assessing their potential risk.

One of the key considerations to note is that women who are pregnant and part of a group recommended to receive the Covid-19 vaccine, such as healthcare personnel, may choose to be vaccinated after thorough discussions with their doctor.


Will Your Immune System Protect You From COVID-19 After Vaccination?

None of us ever expected that our lives would change indefinitely when the COVID-19 pandemic took over the entire world by storm. We are now left to embrace the ‘new normal’ of living. Something that still needs getting used to. Some light did come to show early this year when some pharmaceutical companies begun rolling out the much-awaited COVID-19 vaccine. Even so, they are increasing the production of these vaccines as we progress daily.

This is a step in the right direction as it prepares us to return to normal life by achieving herd immunity – a term used to describe a huge population that is immune to a virus. Through herd immunity, the risk of large-scale outbreaks – like we have seen over the past year – is significantly reduced 1 . However, two important questions remain – can you still get infected with COVID-19 after taking the vaccine, and are you eligible for the vaccine if you have previously tested positive for the virus? Let’s find out together.

Can those who get vaccinated still contract COVID-19?

Let us first understand that the COVID-19 vaccines that were developed have been found to be effective at preventing a COVID-19 infection. However, there is still a minor possibility that you can contract COVID-19 despite being vaccinated. Rest assured, that it is a very slim chance and with vaccination already taking place at break speed, the risk of COVID-19 infections become even lower.

It’s also important to be aware that the coronavirus vaccine might not have enough time to provide complete protection - not that it is ineffective against COVID-19. This is why mRNA vaccinations need to be given in two dosages and require approximately two weeks to fully activate our immune system response.

So even if an individual has received the vaccination, practicing cautions in social or physical distancing as well as basic hygiene is crucial.

Can those who have been previously diagnosed with COVID-19 be vaccinated?

A person can take the vaccine until the person has recovered from the acute illness (if the person had symptoms) and they have met criteria to discontinue isolation. Why? Getting vaccinated can offer a stronger and reliable immune system response to a past COVID-19 infection as compared to the natural immunity developed by the body.

As a matter of fact, those who have recovered from COVID-19 were found to have antibodies that were up to 10 times higher than vaccinated individuals who did not previously test positive for COVID-19 . But those with pre-existing immunity experienced systemic side effects such as fatigue, headache, chills, fever, and muscle or joint pains with considerably higher frequency This is why those who fall in this category are also encouraged to sign-up for vaccination as soon as possible.

Will life return to normal for those who have been vaccinated?

Hopefully it will. The most important thing is to do your duty as a good citizen by signing up for the vaccination. However, getting vaccinated against COVID-19 should not be considered a substitute for basic precautionary measures. We should always remember to do our part by practicing good hygiene habits like regular hand-washing, masking up when outdoors, and adhering to social distancing measures. By doing this, we are one step closer to beating the pandemic once and for all.


How do the new COVID-19 virus strains affect me?

Studies have shown that it is natural for any type of virus to evolve into newer variants. It simply means that viruses can mutate after some time. This doesn’t mean that they are a new form of a virus, but rather a different kind of the same virus.

Best way to describe this is is to think of them as being part of the same family. Now, these new strains may cause some changes that are a little different from how we understand the original virus to be. While many would panic especially when we keep hearing about the COVID-19 new variants, its best we first understand how this mutation works.

It’s true, new strains can either increase or decrease the risk of a virus being contagious. These strains may also affect the severity or level of an infection. So, in the case of COVID-19, how exactly do new strains affect the level of symptoms? Does it impact the effectiveness of the different vaccines that are already available? Let’s take a closer look at how these happens.

Can a new virus strain cause more severe COVID-19 symptoms?

Before we dive in a little deeper, it’s important to note that virus strains exist because of differences in geographic location. What does that mean, you ask? It means that different countries or regions may have the same primary virus, but new and different virus strains may appear in these places simply because of geographical reasons Let’s look at the virus strain that was originally detected in the UK for example. This virus strain, also known as B117, was found to increase the risk of being contagious by up to 50% compared to the original COVID-19 virus. Whoa!

The South African strain - B1351 - on the other hand, was found to be 50% more contagious than the original COVID-19 virus3. Similarly, the P1 virus strain that was first detected in Brazil was found to be up to 2.2 times more contagious than the B117 variant. Pretty intense we would say, but does a higher risk of being contagious mean that there are more severe COVID-19 symptoms?

Meanwhile, B117 (UK) and B1351 (South Africa) have not been found to affect the level of COVID-19 symptoms experienced. However, more data is required to understand the level of COVID-19 symptoms experienced by those infected with the P1 (Brazil) strain.

More recently is the strain discovered out of India (B.1.617) which has caused global record numbers in daily infections within the country over the past weeks. It’s still too early to say if this strain is the cause of rapid spread in India, but experts are treating it as such. It’s also being called a “super mutation” that will make its way around to the rest of the world. Oh no! This strain has already been detected in countries like Germany, Belgium and even in the U.K.

This is why it’s important to continue practicing basic precautionary measures and get vaccinated as soon as possible. Through this, you are doing your civic duty as a responsible citizen to prevent further widespread of these new strains.

Can a new virus strain affect the effectiveness of the different vaccines available?

According to the World Health Organisation (WHO), there is no reason to believe that these COVID-19 virus strains can cause any vaccine to be ineffective We can totally breathe easy now! This is because COVID-19 vaccinations give our bodies some sort of protection by working with our immune system, which is the body’s natural defense against viral infections. Through this, our bodies’ natural defenses cover a wide range of COVID-19 infections, even the new variants.

On a brighter note, it’s also possible to make changes to existing vaccines so that they offer better protection against different COVID-19 virus strains1. This will be especially important if data ever shows that these new strains cause the COVID-19 vaccines to be not effective, however there is no such news yet. We know, what a relief!

What can you do to prevent COVID-19 virus strains?

Ultimately, it’s important for you to get vaccinated as soon as possible to prevent a COVID-19 infection. And by keeping the spread of the primary virus low, you help to reduce the risk of creating new virus strains in your country or region. Pretty simple, no? At the same time, it’s recommended that you carry on practicing basic measures such as regular hand-washing, masking up, and maintaining social distancing in public areas. By doing this, you can help to reduce the contagiousness of the main COVID-19 virus, whilst reducing the risk of COVID-19 virus strains altogether1. You’ve got this, people!




1. Who can take the COVID-19 vaccine?

All individuals 18 years of age and older.

However, some community groups need further consideration for the acceptance of this vaccination, namely:

  • Individuals with severe allergies
  • COVID-19 positive individuals
  • Individuals with immune system problems

Currently, most of the clinical trials conducted are for volunteers aged 18 and over. Some vaccine companies will conduct clinical trials on children. Therefore, the government will consider the use of the COVID-19 vaccine in children when there is scientific data that proves its effectiveness and safety to this group

For women who are pregnant or breastfeeding, do consult with your doctor if you should be vaccinated.

2. Should I get vaccinated if have / had COVID-19?

Yes, according to CDC. This is because experts do not yet know how long someone is protected from getting sick again after recovering from COVID-19.

3. How many doses are required for COVID-19 vaccine?

Most vaccines require 2 doses. For vaccines that require two doses, each individual will get a vaccine of the same type.

4. How long should I wait to get second COVID-19 vaccine shot?

The duration of receiving the second dose will depend on the type of vaccine allocated. The interval between the first and second dose of COVID-19 vaccine types below are as follows;

  • Pfizer & Sputnik V vaccine - 21 days
  • AstraZeneca vaccine - 4 weeks to 12 weeks
  • Sinovac vaccine - 14 days
5. Is there a difference between the first and second vaccine doses?

Both doses are the same, however two shots are required to be fully effective.

6. Why are second doses of vaccines necessary?

The vaccinations goal is to develop a maximum number of antibodies in our system to protect us from someone who has COVID-19. The second dose gives us the most protection from becoming seriously ill and/or hospitalized due to COVID-19.



1. What do we need to do after receiving the vaccine?
  • The vaccines protect against symptomatic forms of COVID-19, but it is still unclear whether they will stop the spread of COVID-19 virus. Therefore, you should still continue to take appropriate precautions in protecting yourself and others around you even after receiving the COVID-19 vaccine.
  • If you are experiencing pain or discomfort after getting vaccinated, speak with your doctor about taking over-the-counter medicine to relief pain and discomfort.
2. Can someone still get COVID-19 after vaccination?

Though it’s unlikely, but some people may still spread and even develop COVID-19 after getting a vaccinated.

3. How long does immunity last after COVID-19 vaccination?

Currently it is unclear of how long the immunity will last as COVID-19 vaccines were only introduced in late 2019.

4. How long does it take to build immunity after getting the COVID-19 vaccine?

According to CDC, it typically takes a few weeks for the body to build immunity (protection against the virus that causes COVID-19) after vaccination. This also means that it’s possible for a person to be infected with the virus just before or just after vaccination and still get sick. This is because the vaccine has not had enough time to provide protection.


Safety & Side Effects

1. How is the vaccine evaluated and approved?

Like other pharmaceutical products, vaccines are constantly monitored in terms of quality, effectiveness and safety. Right now, only the Pfizer-BioNTech vaccine has been given conditional approval based on strict compliance standards through the evaluation of scientific, clinical and technical data. The National Pharmaceutical Regulatory Agency (NPRA) is the body responsible for evaluating the vaccines to be registered in Malaysia. The Drug Control Authority (DCA), on the other hand, approves the use of the vaccines based on the results of NPRA’s evaluation. Each group of vaccines that will be used in Malaysia will be monitored from the aspect of compliance, according to WHO standards. After the vaccine is administered in Malaysia, monitoring of Adverse Events Following Immunization (AEFI) will be carried out by MOH.

2. Is the vaccine safe?

Yes, all COVID-19 vaccines approved by the National Pharmaceutical Regulatory Division (NPRA) for use in Malaysia are safe and effective.

NPRA is the body responsible for evaluating vaccines to be registered in Malaysia. So far, the COVID-19 vaccine for Malaysia has been given conditional approval based on strict compliance with the assessment of scientific, clinical and technical data. The Drug Control Authority (PBKD) will approve the use of the vaccine for Malaysia based on the results of the NPRA assessment.

3. Efficacy of COVID-19 vaccine and why is it different?

The efficacy of a vaccine, or how well the vaccine works, is seen through its ability to protect individuals from the symptoms of COVID-19 through vaccination. The efficacy level varies according to the way clinical studies are conducted, the type of vaccine, the risk of disease in volunteers and various other factors. Although the efficacy level varies, WHO has prescribed that the minimum level of efficacy for the COVID-19 vaccine is 50%.All vaccines approved by NPRA are safe and efficacious for use in Malaysia.

4. Side effects of the COVID-19 vaccine

The side effects of the COVID-19 vaccine that have been reported are mild and temporary. The most commonly reported side effects are:

  • pain/swelling/redness at the injection site
  • tiredness
  • headache
  • chills
  • joint pain
  • fever
  • nausea
  • feeling unwell
  • swelling of the lymph nodes
  • other side effects that may be reported from time to time
5. Will this vaccine provide 100% cure?

Not all vaccines can and will provide 100% cure to any diseases.

6. Will individuals who obtained the vaccine still be able to transmit the disease?

The vaccine will enhance the individual’s antibody. Hence they are less likely to contract or transmit the disease.

7. Is it safe for pregnant mothers to be vaccinated?

In Malaysia, pregnant mothers are not excluded from the vaccination program. They are advised to take the first dose of vaccine from week 14 -33 of pregnancy.

For women who are pregnant or breastfeeding, do consult with your doctor if you should be vaccinated.
However, please note that the Malaysian Government only allows the Pfizer Vaccination if you are pregnant or breastfeeding.

8. Should I get COVID-19 vaccine while I’m breastfeeding? Is it safe for me and my baby?

Currently there is no evidence to proof adverse effect of on breast feeding for new-born babies. However, this is subjected to the mutual decision between mother and O&G consultant.

For women who are pregnant or breastfeeding, do consult with your doctor if you should be vaccinated.
However, please note that the Malaysian Government only allows the Pfizer Vaccination if you are pregnant or breastfeeding.


Ministry of Health Malaysia, Word Health Organisation (WHO), Centres for Disease Control and Prevention (CDC)
For the latest information about COVID-19 Vaccines, please visit Ministry of Health Malaysia.
Last reviewed 1 March 2021

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