A COVID‑19 vaccine provides acquired immunity against severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2), the virus that causes coronavirus disease 2019 (COVID-19).
Types of COVID-19 vaccines
There are 5 main types of COVID-19 vaccines:
Messenger RNA (mRNA) vaccines, such as Moderna/Spikevax and Pfizer-BioNTech (Comirnaty). mRNA vaccines contain material from the COVID-19 virus that instructs our cells to produce a protein that is unique to the virus. After our cells make copies of the protein, they destroy the genetic material from the vaccine. Our bodies recognise that the protein should not be present and work to produce antibodies to attack the virus.
Inactivated whole virus vaccines, such as Sinovac and Sinopharm. These vaccines use weakened or inactive viral particles to stimulate our body to produce antibodies that will help neutralise the COVID-19 virus. Parkway Shenton clinics offer the Sinopharm vaccine. You may choose to take the Sinopharm vaccine as part of your primary series vaccination or as a booster dose.
Viral vector vaccines, such as Oxford AstraZeneca, Johnson & Johnson, CanSino and Sputnik V. These vaccines use a modified harmless virus to induce your cells to make viral proteins. Your body’s immune system then mounts a defence against it.
Protein subunit vaccines, such as Novavax. These vaccines use specific parts of the virus only, which is enough to trigger an immune response.
Bivalent vaccines, such as the Pfizer-BioNTech/Comirnaty bivalent COVID-19 booster vaccine and the bivalent Moderna/Spikevax vaccine. These vaccines offer protection against 2 different variants of the COVID-19 virus – the original SARS-CoV-2 virus, and the Omicron variant(s). Compared with the original mRNA vaccines, these new bivalent COVID-19 vaccines also offer added protection against newer COVID-19 variants, including XBB.
Why do you need a COVID-19 vaccine?
COVID-19 is a highly contagious disease that can cause severe illness and death, especially among the elderly and other vulnerable persons (e.g. persons with 2 or more illnesses, or women who are pregnant).
Vaccination protects you and your loved ones from getting seriously ill or dying from a COVID-19 infection. Vaccination also helps to lower the risk of transmission and prevent Singapore's healthcare system from being overwhelmed.
Who should not take a COVID-19 vaccine?
COVID-19 vaccination is not recommended under these conditions:
You have a history of allergic reactions of anaphylaxis to a COVID-19 vaccine or its components. Anaphylaxis is a severe, life-threatening reaction that includes 2 or more of these criteria:
Hives or swelling of the face, eyelid, lip or throat
Difficulty breathing
Dizziness
You are severely immunocompromised. Although it is still possible for you to take a COVID-19 vaccine, please consult your doctor on your suitability and appropriate windows to be vaccinated if you:
What are the risks and complications of taking COVID-19 vaccines?
COVID-19 vaccines are safe for the general population. Very rare complications include:
Myocarditis (inflammation of the heart muscle)
Pericarditis (inflammation of the membrane surrounding the heart)
These adverse events have been reported following the second dose of mRNA COVID-19 vaccines and were mostly reported in younger men aged 12 – 29 (40.6 cases of myocarditis per million second doses).
Serious side effects to COVID-19 vaccines are rare and may include anaphylaxis, which is a severe and potentially life-threatening allergic response. Anaphylaxis may involve hives or swelling of the face, eyelid, lip or throat, difficulty breathing or dizziness.
How do you prepare for a COVID-19 vaccination?
On the day of the vaccination, wear short-sleeved attire, or sleeves loose enough to be rolled up.
If you are unwell or had a fever in the past 24 hours, please stay home and postpone your vaccination till you recover.
What can you expect when you receive a COVID-19 vaccination?
You may experience some side effects from the vaccine, which are normal signs that your body is responding to the vaccine. If you are taking the Sinopharm vaccine:
The first 2 doses are administered with an interval of 3 – 4 weeks.
You should take your third dose 90 days after your second dose.
Before the procedure
There will be a round of medical screening conducted on-site to check your eligibility for the vaccine. To be eligible for the Sinopharm vaccine, you should:
Be at least 18 years old.
Not have had allergic reactions to vaccines previously.
Not have any known allergies (including anaphylaxis) to any components of the vaccine.
Not have uncontrolled epilepsy or other progressive nervous system diseases, nor a history of Guillain-Barre syndrome.
Consult your obstetrician to assess your suitability for the vaccine if you are pregnant.
During the procedure
The vaccine is administered via an injection into your arm. The process is quick and relatively painless.
After the procedure
You will be observed for approximately 30 minutes after your vaccination. Should you develop any adverse reactions to the vaccine, please alert your care team immediately.
Some people will experience mild to moderate side effects hours after receiving COVID-19 vaccines. Common side effects include:
Pain or redness at the injection site
Muscle ache
Tiredness
Headache
Chills
Fever
Not everyone will experience side effects. Most side effects go away on their own within a few days.
Care and recovery after a COVID-19 vaccination
If you experience side effects such as fever, tiredness or muscle aches, you should:
Rest well
Avoid strenuous activities
Take medication to relieve fever and pain, if necessary
Mild side effects usually resolve on their own after a few days.
Frequently asked questions
A: The Sinopharm COVID-19 vaccine (BBIBP-CorV) is the first China-made vaccine to be approved by the World Health Organisation (WHO). It was approved in December 2020.
The Sinopharm vaccine is an inactivated vaccine, a tried-and-tested form of vaccine technology used in other well-established vaccines, such as the flu and hepatitis B vaccines.
The Sinopharm vaccine provides an alternative for people in Singapore who have previously been found unsuitable to receive the mRNA options. This includes those who have taken a dose of Pfizer or Moderna vaccine and had an allergic reaction.
The Sinopharm vaccine uses weakened or inactive viral particles to stimulate our body to produce antibodies that will help neutralise the COVID-19 virus.
A: The Sinopharm vaccine is known to be 79% effective in preventing symptomatic infection, according to a multi-country ongoing clinical trial.
In comparison, the efficacy rate is 51% for the Sinovac vaccine and 95% for the Pfizer-BioNTech/Comirnaty vaccine.
More studies are required to prove its efficacy against COVID-19 variants.
A: Yes, you can take the Sinopharm vaccine to complete your primary vaccination series or as a booster.
A: The number of doses you need depends on whether you have had a COVID-19 infection and your vaccination history.
If you are unsure of how many doses you need for the Sinopharm vaccine, please book an appointment for 1 dose first and consult our doctors for further advice.
If you have not been infected by COVID-19 before
You may need 1 – 3 doses, depending on your vaccination history and primary vaccination series:
No previous COVID-19 vaccine
You should take 3 doses, based on the following dosing schedule:
Dose 1: Day 0
Dose 2: 21 days after dose 1
Dose 3: 90 days after dose 2
1 dose of Sinopharm, Sinovac or Pfizer
You should take 2 doses, based on the following dosing schedule:
Dose 1: 21 days after the previous dose was taken
Dose 2: 90 days after dose 1
1 dose of Moderna
You should take 2 doses, based on the following dosing schedule:
Dose 1: 28 days after the previous dose was taken
Dose 2: 90 days after dose 1
2 doses of Sinopharm
You should take 1 dose 90 days after the last dose was taken.
2 doses of mRNA vaccine (Pfizer or Moderna)
You should take 1 dose 5 – 6 months after the last dose was taken.
Any other vaccine (e.g. AstraZeneca, Janssen), regardless of the number of doses
You should take 2 doses, based on the following dosing schedule:
Dose 1: 28 days after other vaccine
Dose 2: 21 days after dose 1
If you have recovered from a COVID-19 infection before
You do not need a Sinopharm booster dose if:
You had 2 doses of the Pfizer or Moderna vaccines before your infection.
You had 1 dose of Pfizer or Moderna and 1 dose of Sinopharm (regardless of the order taken) before your infection.
You had any other vaccines (e.g. AstraZeneca, Janssen) before your infection.
If you do not meet the criteria above, you may need 1 – 2 doses, depending on your history of vaccination, infection and recovery:
No previous COVID-19 vaccine, followed by infection and recovery
You should take 2 doses based on the following schedule:
Dose 1: 90 days from date of infection (Positive PCR result)
Dose 2: 21 days after dose 1
1 dose of Sinopharm, Sinovac or Pfizer, followed by infection and recovery
You should take 2 doses based on the following schedule:
Dose 1: 90 days from date of infection (Positive PCR result)
Dose 2: 21 days after dose 1
2 doses of Sinopharm or Sinovac, followed by infection and recovery
You should take 1 dose 90 days from your date of infection (Positive PCR result).
Note:These dosages are recommended guidelines and are subject to changes at any time as more data becomes available.
A: The most common side effects of the Sinopharm vaccine are:
Pain at the injection site
Headache
Fatigue
Most side effects reported were mild to moderate. However, 2 serious side effects may possibly be linked to the Sinopharm vaccine:
Serious nausea
Acute disseminated encephalomyelities, a neurological disorder involving inflammation of the brain and spinal cord.
A: Both the Sinopharm and Sinovac vaccines are inactivated vaccines and require 3 doses.
The Sinopharm vaccine, however, has been proven to be 79% effective in preventing symptomatic disease, compared to 51% for the Sinovac vaccine.
According to the World Health Organization, the recommended interval between the first and second dose for the Sinopharm vaccine is 3 – 4 weeks, compared to 2 – 4 weeks for the Sinovac vaccine.
The third dose of the Sinopharm or Sinovac vaccine can be taken 90 days after the second dose.
A: The Ministry of Health in Singapore has stated that only vaccines that comply with the World Health Organization’s guidelines and adhere to strict standards of safety, quality and efficacy have been identified and will be used in Singapore.
A: No vaccine is 100% effective in preventing an infection, but they help to reduce the severity of the illness should you be infected. Vaccinated individuals infected with COVID-19 tend to have moderate or mild symptoms or no symptoms at all.
A: Yes, but each vaccine's efficacy against new variants of COVID-19 is different. Bivalent COVID-19 vaccines offer protection against the original SARS-CoV-2 virus, as well as newer variants such as Omicron and XBB.
For Omicron, there is an emerging view internationally that the current COVID-19 vaccines will still work, especially against severe illness. Fully vaccinated travellers who were infected have shown mild symptoms so far. Nevertheless, more information will be needed on each vaccine's effectiveness against the Omicron variant.
A: The 2 vaccines target different viruses. Therefore, it is recommended that while you protect yourselves against COVID-19, it is also prudent to get an influenza vaccine.
A: No, as COVID-19 vaccines are not 100% effective against infection. Masks can help to protect individuals that are unable to take the coronavirus vaccines or do not wish to do so.
For these reasons, it is recommended to continue current safety practices such as regular hand washing and sanitisation, wearing your masks, and keeping to social distancing measures.
Why choose Mount Elizabeth Hospitals?
Established for more than 40 years in Singapore, Mount Elizabeth Hospitals have earned the trust of patients from the region. Staffed by a team of infectious disease specialists, we are here to help you achieve the best possible healthcare outcome.
Our infectious disease specialists and respiratory specialists
At Mount Elizabeth Hospitals, our specialists keep their fingers on the pulse of developments in managing and treating infectious diseases such as COVID-19. They are supported by a team of nurses and staff who are experienced in responding to your healthcare needs.
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