FAQs on General Vaccine Recommendations

26 May 2023

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General Vaccine Recommendations
  • Why is there a need for three mRNA doses for minimum protection?
  • I was infected with COVID-19 before I could complete the doses required for minimum protection. Is the COVID-19 infection considered as a dose?
  • I have recovered from COVID-19. How soon can I receive my next vaccination dose?
  • I have completed three doses of Sinovac-CoronaVac. Do I need to receive a fourth dose of Sinovac-CoronaVac?
  • Can I be vaccinated if I am ill on the day of vaccination?
  • Do all vaccine doses need to be of the same brand and vaccine composition?
  • Can I receive other non-COVID-19 vaccines at the same time as the COVID-19 vaccine? How long do I have to wait before getting other vaccines?
  • I had received my second booster as recommended previously. Am I still recommended to receive another booster in 2023?
Who can receive the vaccine
  • Who should not get the mRNA-based COVID-19 vaccines?
  • What is the recommendation for persons who are unable to receive the mRNA vaccines (i.e. Pfizer-BioNTech/Comirnaty or Moderna/Spikevax vaccines)?
  • Who should not get the Novavax/Nuvaxovid COVID-19 vaccines?
  • Who should not get the Sinovac-CoronaVac COVID-19 vaccines?
  • Can individuals with a history of allergies or anaphylaxis to other medications, drugs, food, insect stings, or unknown triggers (idiopathic) take COVID-19 vaccine?
  • Are the vaccines safe for pregnant or breastfeeding women?
Medically Vulnerable and Immunocompromised
  • Who are considered medically vulnerable persons?
  • Immunocompromised persons may not develop good immune responses to vaccination and may need additional doses. Who are immunocompromised persons? What vaccine doses should they receive, and how can they do so?
  • Who are considered severely immunocompromised? Can severely immunocompromised persons receive the mRNA-based vaccine?
  • Can persons with active cancer be vaccinated?
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General Vaccine Recommendations

 Why is there a need for three mRNA doses for minimum protection?
 A: Local and international data in ages 5 years and above show reduced vaccine protection against COVID-19 from around six months after completion of the second mRNA vaccine dose. The level of protection drops even further over time. Three doses of mRNA vaccine are therefore necessary to achieve a good level of protection.
 I was infected with COVID-19 before I could complete the doses required for minimum protection. Is the COVID-19 infection considered as a dose?
 A:For minimum protection, you are recommended to receive three doses of mRNA or Novavax/Nuvaxovid vaccines, or four doses of Sinovac-CoronaVac regardless of any past infections.
 I have recovered from COVID-19. How soon can I receive my next vaccination dose?
 A:You can schedule your next dose at appointment.vaccine.gov.sg to take place 28 days after the infection, if you are due for your vaccination. 

For better effectiveness however, you are recommended to receive your next vaccine dose three months after the infection or the recommended interval for your next dose, whichever is later.
 I have completed three doses of Sinovac-CoronaVac. Do I need to receive a fourth dose of Sinovac-CoronaVac? 
 A:Persons who have received three doses of COVID-19 vaccines, of which two or more doses of comprise Sinovac-CoronaVac*, are recommended to receive a fourth dose of either the Pfizer-BioNTech/Comirnaty, Moderna/Spikevax or Novavax/Nuvaxovid vaccine to achieve minimum protection, unless medically ineligible for the abovementioned vaccines. However, they can receive Sinovac-CoronaVac as their fourth dose if they choose to.

Those who received an mRNA or the Novavax/Nuvaxovid vaccine as their third dose should receive the fourth dose about five months thereafter.

Those who received the Sinovac-CoronaVac vaccine as their third vaccine dose should receive the fourth dose at three months thereafter, due to lower antibody levels generated by the third vaccine dose.

*Recommendations for Sinovac-CoronaVac should similarly apply to Sinopharm
 Can I be vaccinated if I am ill on the day of vaccination?
 A:If you are unwell, please reschedule your vaccination at appointment.vaccine.gov.sg or by clicking on the booking link sent via SMS to your phone.
 Do all vaccine doses need to be of the same brand?
 A:For Pfizer-BioNTech/Comirnaty, Moderna/Spikevax or Novavax/Nuvaxovid, your first two doses of vaccine should be of the same brand. Subsequent doses of vaccine can be of different brands, where applicable.

From time to time, the composition of a COVID-19 vaccine may be updated to target more recent virus variants. If you are due for a vaccine dose, you are recommended to receive the updated version of the vaccine. There is no need for your vaccine doses to be of the same composition.

 Can I receive another (non-COVID-19) vaccine at the same time as COVID-19 vaccine? How long do I have to wait before getting other vaccines?
 A:An interval of at least 14 days before or after a  non-COVID-19 vaccine is encouraged. 

However, persons above 5 years old can be vaccinated, even if they had received a non-COVID-19 vaccine within 14 days of the COVID-19 vaccination.

Children aged 6 months to 5 years may be vaccinated under the National Vaccination Programme within 14 days of a non-COVID-19 vaccine, if recommended / referred to do so by a doctor via a memo.
 I have received my second booster as recommended previously. Do I still need to receive another booster in 2023?
A: Regardless of the number and composition (monovalent/bivalent) of previous booster doses received, the following groups who have achieved minimum protection (e.g. 3 doses of mRNA vaccines) are recommended to receive in 2023, one booster dose of COVID-19 vaccine at an interval of one year after their last booster dose:

(a) ages 60 years and above,
(b) medically vulnerable persons who are aged 12 years and above, or, 
(c) residents living in aged care facilities.

They can start to receive it from five months after their last booster dose.

Other persons aged 12 years and above may also do so if they choose to.

Who can receive the vaccine

 Who should not get the mRNA-based COVID-19 vaccines?
 A: The mRNA-based COVID-19 vaccines, Pfizer-BioNTech/Comirnaty and Moderna/Spikevax, are currently not available for children under the age of 6 months.

Persons with a history of anaphylaxis to mRNA COVID-19 vaccine or its components SHOULD NOT receive the mRNA-based vaccine again. Anaphylaxis is a severe life-threatening reaction with two or more of the following three criteria:

a) Hives or face/eyelid/lip/throat swelling;
b) Difficulty breathing;
c) Dizziness.

Patients with the following high-risk allergic reactions to a previous dose of mRNA COVID-19 vaccine or its components SHOULD NOT be administered the vaccine.
a) Hives or face/eyelid/lip/throat swelling with onset within 4 hours post-vaccination
b) Painful swelling of the inner surfaces of the mouth and/ or large blisters spontaneously occurring at any time after vaccination.

Persons with a history of allergic reactions (including anaphylaxis) to other vaccines CAN receive the mRNA-based vaccine, unless they have a confirmed allergy specific to PEG (which is a component of the mRNA vaccine). Persons who were diagnosed with myocarditis after a dose of mRNA COVID-19 vaccines SHOULD NOT receive the vaccine again.

Persons who cannot get the mRNA vaccines due to the high-risk allergic reactions indicated above, including persons who a confirmed allergy specific to PEG, should be vaccinated with the Novavax/Nuvaxovid vaccine.
Persons who were diagnosed with myocarditis/pericarditis after a previous dose of mRNA COVID-19 vaccine SHOULD NOT receive the Novavax/Nuvaxovid vaccine.

The Sinovac-CoronaVac vaccine should only be considered for use by persons who cannot receive both the mRNA vaccines and Nuvaxovid.
 What is the recommendation for persons who are unable to receive the mRNA vaccines (i.e. Pfizer-BioNTech/Comirnaty or Moderna/Spikevax vaccines)?
 A:Persons who are unable to receive the mRNA vaccines are recommended to receive the Novavax/Nuvaxovid vaccine, except those who were diagnosed with myocarditis/pericarditis after a previous dose of an mRNA vaccine. The Sinovac-CoronaVac vaccine should only be considered for use in persons who are medically ineligible to receive mRNA vaccines and the Novavax/Nuvaxovid vaccine.
 Who should not get the Novavax/Nuvaxovid COVID-19 vaccines?
 A:The Novavax/Nuvaxovid vaccine should not be received by persons under the age of 12 years.

Persons with a history of anaphylaxis to the Novavax/Nuvaxovid vaccine or its components, or were diagnosed with myocarditis/pericarditis after a previous dose of an mRNA vaccine or Novavax/Nuvaxovid SHOULD NOT receive the Novavax/Nuvaxovid vaccine.

Anaphylaxis is a severe life-threatening reaction with two or more of the following three criteria:

a) Hives or face/eyelid/lip/throat swelling;
b) Difficulty breathing;
c) Dizziness.
 Who should not get the Sinovac-CoronaVac COVID-19 vaccines?
 A:Persons who are able to take mRNA vaccines are encouraged to do so, in preference to the Sinovac-CoronaVac vaccine, given the higher efficacy of the mRNA vaccines.

The Sinovac-CoronaVac vaccine is not recommended for persons under the age of 18 years until more efficacy and safety data is submitted to HSA for evaluation. 

Persons with a history of allergic reactions or anaphylaxis to the Sinovac-CoronaVac vaccine, its components, or other inactivated vaccines SHOULD NOT receive Sinovac vaccine again. Anaphylaxis is a severe life-threatening reaction with two or more of the following three criteria:

a) Hives or face/eyelid/lip/throat swelling;
b) Difficulty breathing;
c) Dizziness.
 Can individuals with a history of allergies or anaphylaxis to other medications, drugs, food, insect stings, or unknown triggers (idiopathic) take COVID-19 vaccine?
 A:Individuals with a history of anaphylaxis to other medications, drugs, food, insect stings, or unknown triggers (idiopathic) CAN be vaccinated.

There is no evidence to suggest that individuals with a history of anaphylaxis to non-vaccine related triggers are at higher risk of anaphylaxis to the COVID-19 vaccines.

However, individuals with an allergy to other inactivated vaccines should NOT receive the Sinovac-CoronaVac.
 Are the vaccines safe for pregnant or breastfeeding women?
 A:Pregnant or breastfeeding women can receive the COVID-19 vaccines.

Pfizer-BioNTech/Comirnaty and Moderna/Spikevax Vaccines
Internationally, a large number of pregnant and breastfeeding women have received a COVID-19 vaccination.  The Expert Committee on COVID-19 Vaccination (EC19V) has examined studies done to monitor women who were vaccinated when they were pregnant, and their babies. These studies were done on women at different trimesters of pregnancy and there is no evidence to suggest that the Pfizer-BioNTech/ Comirnaty or Moderna/Spikevax COVID-19 vaccine may cause harm to pregnant women or their babies.

Both Pfizer-BioNTech/Comirnaty and Moderna/Spikevax COVID-19 vaccines are mRNA vaccines. As mRNA vaccines are not live vaccines, they are biologically unlikely to adversely affect breastfed babies. In addition, the breast milk of vaccinated mothers may help to protect their babies from COVID-19 due to antibodies in breast milk. There have also been no vaccine-related side effects reported in the babies who were breastfed by mothers who received the vaccine while breastfeeding.

Sinovac-CoronaVac and Novavax/Nuvaxovid Vaccine
There is currently limited data in pregnant women. Nevertheless, the Sinovac-CoronaVac vaccines is an inactivated vaccine, while Novavax/Nuvaxovid is a protein subunit vaccine. These vaccines are routinely used in many other vaccines with a documented good safety profile, including in pregnant women.

Medically Vulnerable and Immunocompromised

 Who are considered medically vulnerable persons?
 A: Medically vulnerable persons are individuals who are at increased risk of severe COVID-19 due to significant medical risk factors. These include persons with chronic diseases of the heart, lungs, kidneys, liver and other organ systems. 

A list of specific health conditions that will classify one as medically vulnerable can be found here. If you are unsure, you should consult your doctor.
 Immunocompromised persons may not develop good immune responses to vaccination and may need additional doses. 
• Who are immunocompromised persons?
• What vaccine doses should they receive, and how can they do so?
 A:Immunocompromised persons have significantly impaired immune system which include persons with the following conditions:

a) Transplant patients on medications that suppress the immune system, including solid organ and allogenic stem cell transplants
b) Cancer patients on active treatment with chemotherapy or on other therapies that suppress the immune system
c) Haematological cancers
d) Treatments for non-cancer conditions that suppress the immune system
e) End-stage kidney disease
f) Advanced or untreated HIV

Persons aged 5 years and above with these conditions should complete, as applicable, three mRNA or Novavax/Nuvaxovid doses, or four Sinovac-CoronaVac doses, to achieve minimum protection. After achieving minimum protection, they should receive an additional booster dose between five months to one year from their last dose, to keep up-to-date with their COVID-19 vaccination. The updated bivalent vaccine is recommended for this in eligible age groups.

Persons who are aged 18 years and older with these conditions may self-declare their health conditions and receive an additional booster dose. They may walk into any Joint Testing and Vaccination Centre and verbally declare to the vaccination staff on-site of their health conditions before receiving their vaccination. Persons who are aged below 18 years are able to receive the additional booster dose with a doctor’s referral.

Doctors may advise some immunocompromised patients to receive an extra dose of the vaccine earlier in between the three mRNA doses recommended for minimum protection as part of an “enhanced primary series”. They can do so with their doctor’s referral.

 Who are considered severely immunocompromised? Can severely immunocompromised persons receive the mRNA-based vaccine?
 A:The following are some examples of severely immunocompromised persons, but there may be other examples not on this list.
·       Transplant within the past 3 months (solid organ or stem cell)
·       Aggressive immunotherapy (e.g. Rituximab) for non-cancer conditions
Severely immunocompromised persons can be vaccinated. However, they are encouraged to discuss their optimal timing for COVID-19 vaccination with their doctor, and would need to obtain a memo from their doctor to be vaccinated.

If in doubt, Individuals will also be assessed by the medical personnel at the vaccination sites for their suitability to receive the vaccination before they are vaccinated.
 Can persons with active cancer be vaccinated?
 A:Cancer Patients Not on Treatment
Persons with active cancer who are NOT on treatment with chemotherapy, radiotherapy or immunotherapy CAN be vaccinated at any available vaccination site. Active cancer not on treatment is defined as:
• Not being on any of the above treatment in the past 3 months AND
• Not having planned treatment of the above in the next 2 months
Persons with a history of cancer, who are in remission, CAN be vaccinated at any available vaccination site.
 
Cancer Patients on Hormonal Treatment
Persons on active cancer hormonal therapy CAN be vaccinated at any available vaccination site.

Cancer Patients on Active Treatment
Persons on active cancer chemotherapy, radiation therapy or immunotherapy can be vaccinated if they have a memo from their treating oncologist/specialist.

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