Pfizer COVID-19 vaccine

Also called the Pfizer/BioNTech vaccine or Comirnaty vaccine

The Pfizer vaccine protects against COVID-19. It protects you from severe infection, hospitalisation and death. Find out about the vaccine and possible side effects.

On this page, you can find the following information:

Who can get the Pfizer vaccine?

Everyone in Aotearoa New Zealand aged 12 years and over can book their free COVID-19 vaccination now. It doesn’t matter what your visa or citizenship status is. 

The Pfizer vaccine is a highly effective vaccine at preventing you getting the coronavirus disease COVID-19, which is caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2).

Vaccination means that if you do become infected you are far less likely to fall seriously ill or transmit the virus to others.

How does the Pfizer vaccine work?

The Pfizer vaccine works by preparing your body to defend itself against COVID-19. The Pfizer vaccine does not contain the virus itself and cannot cause COVID-19.

The Pfizer vaccine is called an mRNA vaccine. It contains a molecule called mRNA which has instructions for making the spike protein on the surface of the virus. The virus needs this spike protein to enter your body’s cells.

When you are given the vaccine, some of your cells will read the mRNA instructions and temporarily produce the spike protein. Your immune system will then recognise this protein as foreign and produce antibodies to attack it. If, later on, you come into contact with the SARS-CoV-2 virus, your immune system will recognise it and be ready to defend your body against it. The mRNA from the vaccine does not stay in your body but is broken down shortly after vaccination. Learn more about the mRNA vaccines.

How safe is the Pfizer vaccine?

The Pfizer vaccine is safe. Before vaccines are provided to the community, they must be approved by Medsafe, the New Zealand Medicines and Medical Devices Safety Authority. Medsafe only grants consent for a vaccine to be used in New Zealand once they are satisfied it’s safe and effective enough to use. It has given provisional approval for the use of the Pfizer vaccine, the same kind of approval given to the annual flu vaccine.

Medsafe is monitoring the safety of the vaccine as it is rolled out around the country. You can read Medsafe’s latest safety reports on the vaccine here: Overview of vaccine reports.

How effective is the Pfizer vaccine?

No vaccine is 100% effective. The Pfizer vaccine is about 95–97% effective against the COVID-19 virus if you have both doses. This high efficacy means that if you do catch COVID-19, you’re far less likely to fall seriously ill and less likely to transmit the virus to others. Learn more: COVID-19 vaccine effectiveness and protection.

Who should not be vaccinated with the Pfizer vaccine?

The Pfizer vaccine has an excellent safety profile and there are only a handful of people in Aotearoa who cannot receive it.

  • It is currently not licensed for use in children under 12 years of age.
  • If you are currently isolating or experiencing symptoms of COVID-19, you should not be vaccinated until you have recovered and met the criteria to stop isolating.
Before the 1st dose
  • If you have had a previous severe allergic reaction (anaphylaxis) to an ingredient of the vaccine. This is very rare, and only applies to previous anaphylaxis to a stabiliser in the vaccine called polyethylene glycol (PEG). However, this is often unclear as problems with PEG most commonly occur after having it by mouth and there may not be any problem with having it in a vaccine. This will be assessed by an immunology specialist.
After problems with the 1st dose
  • If you have had a severe allergic reaction (anaphylaxis) usually within 15 minutes after the first dose. Increasing experience now shows that many people can be revaccinated safely in a specialist immunology clinic setting. 
  • If you have had myocarditis (inflammation of the heart muscle) or pericarditis (inflammation of the lining around the heart) after their first dose. Myocarditis or pericarditis after the vaccine is rare. Diagnosis requires special tests and often assessment by a heart specialist. 

Learn more about who can't have the Pfizer/BioNTech COVID-19 vaccine?

Note for people with other allergies:

  • Some people develop delayed allergic type symptoms, such as hives and other skin rashes. These people can safely get their second dose (see delayed allergic symptoms below).
  • People with a history of allergy to foods and venom can be vaccinated.
  • People with a history of severe immediate allergic response (anaphylaxis) to another vaccine or multiple drugs can receive this vaccine but are asked to wait to be observed for a little longer after vaccination.

Can I have the Pfizer vaccine if I am pregnant?

You are strongly encouraged to be vaccinated against COVID-19 at any stage of pregnancy.

  • In pregnancy, the risk of severe COVID-19 complications is much higher than in people who are not pregnant. 
  • The use in pregnancy aligns with recommendations in other countries and is based on international evidence from a large number of people who have already received mRNA COVID-19 vaccines when pregnant. No additional safety concerns have been shown.
  • There is also increasing evidence that antibodies made by the mother after vaccination are shared with the baby in the cord blood. These are likely to also protect her newborn baby against COVID-19.

Note: Pregnant women are advised to get the COVID-19 vaccine and the influenza vaccine at any stage of pregnancy and whooping cough vaccine from 16 weeks gestation. These can be given at the same time as the COVID-19 vaccine or separately. 

Can I have the Pfizer vaccine if I am breastfeeding?

You can get the Pfizer vaccine if you are breastfeeding. There are no safety concerns about giving the Pfizer vaccine to people who are breastfeeding. By being vaccinated, you can provide some protection against COVID-19 for your baby through your breastmilk. Read more about the use of the Pfizer vaccine in pregnancy and breastfeeding.

Can the COVID vaccine affect fertility?

No, the Pfizer vaccine will not affect your genes or fertility. The mRNA from the vaccine does not enter the nucleus of any cells, which is where your DNA is. Read more here

How is the Pfizer vaccine given?

The Pfizer vaccine is given as an injection into the muscle of your upper arm by a trained healthcare professional. You will be given one dose followed by a second dose. You can choose whether to have it 21 days apart or 6 weeks apart.

  • 6 weeks apart: Having your doses 6 weeks apart has been found to provide a better immune response, and also enables more people to get their first dose sooner. 
  • 21 days apart: There may be some people who are at higher risk, such as immunosuppressed people or those working in higher risk settings like border workers, who may be advised to have their doses 3 weeks apart. Learn more about the time between doses.

It is very important that you receive your second dose. 

The first dose ‘primes’ your immune system but protection doesn’t last as long because the level of antibodies falls. A second dose gives your immune response a boost. This creates lots more antibodies to help your immune response mature and provide longer protection.

After your vaccination

After getting your COVID jab, a trained healthcare professional will keep an eye on you for at least 15 minutes after being given the Pfizer vaccine to make sure you don't have any reaction to the vaccination. Read more about getting your vaccination and what to expect.

Is my health information protected?

Yes, your information is protected under privacy laws. When you get your COVID-19 vaccination, you will be asked to provide some personal information, such as your name and the date you get your vaccination. It will recorded by the Ministry of Health in a computerised information system called the COVID-19 Immunisation Register. This is similar to how childhood vaccinations are already recorded in the National Immunisation Register (NIR). 

This information may be used to help you manage your health and for the Government to deliver health services such as the COVID-19 vaccination rollout. It will be treated with care to make sure your privacy is protected, as required by the Privacy Act 2020 and the Health Information Privacy Code 2020. Read more about privacy.

Can the Pfizer vaccine be given with other vaccines?

All vaccines (except the shingles vaccine) can be given at the same time or immediately before or after the COVID-19 vaccine. Read more about the COVID vaccine and other vaccines.

What are the common side effects of the Pfizer vaccine?

Like all vaccines, the Pfizer vaccine can cause side effects, although not everyone gets them. They are more commonly reported after a second dose and in younger adults (aged under 55 years). Read more: After your vaccination

 Side effects  What should I do?
  • Pain at injection site
  • Tiredness
  • Headache
  • These are the most common side effects after having the vaccination.
  • They usually start within 6–24 hours after getting the injection. 
  • Place a cold, wet cloth or ice pack on the injection site for a short time.
  • Do not rub or massage the injection site.
  • Tell your doctor if troublesome.
  • Muscle aches
  • Chills
  • Fever
  • Joint pain
  • Feeling unwell
  • Nausea
  • These side effects usually start within 6–48 hours after getting the injection. 
  • Rest and drink plenty of fluids.
  • They may be more common after your second dose of the vaccine.
  • Paracetamol or ibuprofen can be taken but follow the manufacturer’s instructions.
  • Seek advice from your health professional if your symptoms get worse.

Is there a risk of allergic reaction with the Pfizer vaccine?

Serious allergic reactions can occur but are extremely rare. New Zealand vaccinators are trained to manage these. Most people with a history of anaphylaxis to other medicines, vaccines, foods and venom can be safely vaccinated.

Signs of an allergic reaction include skin rash, itching, swelling of your lips, face and mouth, or difficulty breathing. 

  • A trained healthcare professional will observe you for at least 15 minutes after being given the Pfizer vaccine 
  • If these symptoms develop after that, go straight to the emergency department at your nearest hospital.

Delayed allergic symptoms

Some people develop delayed allergic symptoms such as swelling around your eyes or face, hives or rash. This can develop from a few hours to days after getting your vaccine. The symptoms may settle on their own without treatment or you can use antihistamine tablets (eg, cetirizine or loratadine). Tell your doctor if you are concerned.

Most people who develop delayed allergic symptoms with the first dose can be safely given the second dose. You can take an antihistamine (eg, cetirizine or loratadine) prior to or following the second dose. Most people will have a similar milder reaction with the second dose.

Is there a risk of myocarditis with the Pfizer vaccine?

There have been very rare reports of myocarditis and pericarditis occurring after vaccination with the Comirnaty Pfizer COVID-19 vaccine. Note that infection by COVID-19 is far more likely to cause myocarditis than vaccination.

This is what we know so far about myocarditis and the COVID-19 vaccine:

  • Myocarditis has affected fewer than 1 person in 1 million people who have had the Pfizer vaccine in the European Union countries.
  • Cases are typically occurring in men under the age of 30 within days of receiving of the second dose (generally within a week).
  • Cases typically occur in older adults around 21 days after their first or second dose.
  • In most cases, the myocarditis was mild and is not expected to have any long-term effects.
  • When hospitalised the average stay is 2 days.
  • The Pfizer vaccine is highly effective in protecting people from COVID-19 infection.
  • COVID-19 can also cause myocarditis. Infection by COVID-19 is far more likely than vaccination to cause myocarditis. COVID-19 infection is very dangerous to your body in many ways, and vaccination is a key part of protecting yourself and your family.
  • Read more: Myocarditis and pericarditis Medsafe, NZ, 2021

In the first few days after your vaccination seek medical attention if you experience new onset chest pain, shortness of breath or an abnormal heartbeat. These are potential signs of myocarditis.

Is there a risk of blood clots with bleeding with the Pfizer vaccine?

Medsafe has completed a review of the risk of rare cases of blood clots with bleeding reported internationally with some COVID-19 vaccines. To date, all the cases that have been reported after vaccination are linked to the first dose of Vaxzevria (AstraZeneca) or the Janssen COVID-19 vaccines. These vaccines are not currently used in New Zealand. Medsafe continues to monitor this safety signal and remains in contact with international regulators. Read more about COVID-19 vaccines and blood clots.

Learn more

For other reliable and accurate information about COVID-19 vaccines, see:

Getting vaccinated for COVID-19
 The Immunisation Advisory Centre, NZ
Update around management of those with allergic reaction to their first dose of Comirnaty or history of PEG allergy The Immunisation Advisory Centre, NZ


  1. Comirnaty COVID-19 vaccine Medsafe Consumer Information, NZ
  2. Comirnaty European Medicines Agency
  3. Time between doses of COVID-19 vaccine extended Unite against Covid-19, NZ, 2021
  4. Myocarditis and the mRNA COVID-19 vaccine in New Zealand - information for health professionals The Immunisation Advisory Centre, NZ
Credits: Sandra Ponen, Pharmacist. Reviewed By: Maya Patel, MPharm PGDipClinPharm, Auckland Last reviewed: 07 Oct 2021