The COVID-19 Vaccine – What do I need to know?

Updated: Mar 8, 2021

There are two COVID vaccines which have been approved for use in Australia. These are the Pfizer or BIoNTech vaccine and the AstraZeneca or Oxford vaccine. Both have been granted provisional approval by the Australian Therapeutics Goods Administration (TGA). This means that they have been approved for a two-year period only and both Pfizer and Astra Zeneca have to provide constant ongoing safety data to the TGA. If the TGA have any concerns in Australia or overseas they will investigate this straight away and withhold approval. However, it is important to note that the TGA has extremely high standards for safety, efficacy and quality. The Pfizer vaccine has been approved for use in people aged 16 years and above and the Astra Zeneca vaccine has been approved for those 18 years and above. The decision to provide provisional approval was informed by an independent committee with expertise in scientific, medical and clinical fields. Further to this, every batch of vaccine used in Australia will be independently checked by the TGA before it is released for use.

Both the Pfizer and the AstraZeneca vaccines require two doses. The Pfizer vaccine second dose should be given 3 weeks after the first dose; the AstraZeneca second dose should be given 4 – 12 weeks after the first dose. Both vaccines have been shown to be effective against mutant strains of coronavirus.

The roll out of the vaccine will be done in phases, categorising Australians into levels of urgency for vaccination. Prioritisation will be given to Australians most vulnerable to COVID and those most at risk for contracting the virus such as frontline workers. These Australians will be given the Pfizer vaccine. The rest of the population will be given the AstraZeneca vaccine. Both vaccines have been found to be extremely effective, safe and capable of producing herd immunity. Herd immunity is the level of immunity within a population required to allow resistance to the spread of a virus or infectious disease. It can be achieved via vaccination or from enough people having been previously infected with a disease.

Phase 1a) has just begun in hospitals and soon phase 1b) and 2a) will begin at GP respiratory clinics, certain general practices, Aboriginal Community Health Services and state-run vaccination clinics. At some point, workplaces and pharmacies will also get involved. If you would like to know a little more about the phases of vaccination and which category you may be in please see appendix 1 below.

It is optional but highly recommended for all Australians over 18 years to receive the COVID vaccine. It is free for everyone. If you choose not to receive the vaccine, it will not affect any family tax benefits. However, it may affect travel to certain destinations and certain high-risk workplaces might insist on vaccination. When you receive the vaccine you are also helping to stop the spread of coronavirus which in turn helps protect other Australians.

Both vaccines can be given to pregnant women and women who are breastfeeding. However, there is not a large amount of data about the Astra Zeneca vaccine and its use in these groups of women. In particular, there is not a lot of information to tell us how effective it is if you receive the Astra Zeneca vaccine while you are pregnant. We do know that, in the small amount of data available, there have been no harmful effects on the baby during pregnancy and breastfeeding. Pregnant women are being offered the COVID-19 vaccination, and can decide as to whether they have the vaccination while pregnant, or wait until after the pregnancy.

It is absolutely safe to have the COVID vaccine and the flu vaccine this year but please advise your GP when you had the COVID vaccine as there needs to be 14 days between doses of the COVID vaccine and the flu vaccine.

Safety of the Vaccines

Before the Australian TGA approved the two COVID-19 vaccines, they waited for months of safety data. The great majority of vaccine side effects occur within the first few months after administration. In fact, most side effects occur within the first 1 – 2 days and most are minor like pain at the injection site, headache and flu like symptoms. Mild side effects are good; they are a sign that your immune system is building an army of immunity to the virus you’ve been vaccinated against.

Both the Pfizer and the Astra Zeneca viruses have been used overseas and have excellent safety data.

There is a slightly higher risk of anaphylaxis for the Pfizer vaccine, although for all vaccines there is a risk of anaphylaxis and allergy which is why all patients will be asked to stay on site where doctors and nurses can monitor them for at least 15 mins post administration of the vaccine.

If you have a bleeding disorder or are on medications which thin your blood, there is also a slightly higher risk of bruising at the administration site.

For a full list of side effects of the Pfizer vaccine please see Appendix 2 below. The TGA has not yet issued a full list of side effects of the Astra Zeneca vaccine but it is expected to be very similar.

Ingredients of the Vaccines

For a full list of ingredients for the vaccines, please visit the TGA website. Australian Register of Therapeutic Goods.

In general, vaccine ingredients include:

- A protein component of the virus (spike protein) – Astra Zeneca

- A piece of genetic code (mRNA) – Pfizer

- A substance to boost the immune system – adjuvant

- A small amount of preservative

- Sterile salt water (saline)

How the Vaccines Work

The two vaccines do not have the same mechanism of action.

The Pfizer vaccine is an mRNA vaccine. This is a newer technology. A fragment of genetic material, mRNA is injected into your arm. This genetic material teaches your muscle cells to actually make coronavirus proteins. Whilst this is what COVID actually does in nature, the mRNA vaccine does not teach the human body to make the critical COVID protein, so it just teaches your immune system how to recognise COVID and make antibodies so that it will be able to fight off COVID if you ever become infected with it.

It is important to note that although genetic material is being injected into your body, it cannot be transmitted to the next generation meaning that there is no way it can change your genetic make-up or DNA.

The AstraZeneca vaccine is made up of a protein (the spike protein) from the coronavirus that has been inserted into a weakened version of the common cold virus (adenovirus). The adenovirus has been modified to be more like coronavirus. It cannot cause you to get coronavirus. Once injected, the vaccine then enters your own body’s cells and teaches your cells how to recognise the important coronavirus spike protein. Your body then makes its own antibodies to the spike protein. These antibodies learn how to destroy the spike protein so that if you are ever infected with COVID at a later date, your immune system will recognise the spike protein and you will have the ability to fight off COVID.

If you have any other questions or concerns about the vaccine, please come and talk to us at LGP, we are very happy to help in any way we can!

Appendix 1: The Phases of the COVID Vaccine Roll Out (4)

Phase 1a) – Pfizer

- Quarantine, and border workers

- Frontline healthcare workers (hospital ED staff, COVID-19 and respiratory ward, intensive care staff and high dependency unit staff, lab staff, ambulance and paramedic staff, GP respiratory clinic staff, COVID-19 testing staff, aged care and disability staff)

- Aged care and disability care residents

Phase 1b) – AstraZeneca

- Elderly over 80 years

- Elderly 70 – 79 years

- Other health care workers

- Start vaccinating Aboriginal and Torres Strait Islander people

- Adults with a specified medical condition

- Adults with a disability who have a specified medical condition

- Critical and high-risk workers including defence, police, fire, emergency and meat processing

Phase 2a) – AstraZeneca

- Adults 60 – 69 years

- Adults 50 – 59 years

- Continuing vaccinating Aboriginal and Torres Strait Islander people

- Other critical and high-risk workers

Phase 2b) – AstraZeneca

- Rest of the adults

- Catch up of any unvaccinated Australians in above groups

Phase 3)

- Under 16 years if recommended

Appendix 2: Full list of Side Effects of the Pfizer Vaccine (2)

· Very Common side effects

o Headache

o Muscle pain

o Joint pain

o Injection site swelling and tenderness

o Fatigue

· Common side effects

o Nausea

o Injection site redness

· Uncommon

o Pain in arms or legs

o Insomnia

o Malaise

o Injection site itchiness

o Swelling of glands / lymph nodes

· Very uncommon

o Facial paralysis

· Extremely uncommon

o Anaphylaxis


1. Australian Government Department of Health: About the AstraZeneca COVID 19 Vaccine: < 6/03/2021>


3. The University of Western Australia: How we know the COVID vaccine won’t have long term side effects. <6/03/21>

4. Australian Government Department of Health: When will I get the COVID vaccine: <6/03/21 >

5. BBC News: COVID: What is the Oxford-AstraZeneca vaccine? (5/03/21) <6/03/21>

6. Mishra, Sanjay, The Conversation: How mRNA vaccines work and why they need to be kept so cold: (19/05/20) <6/03/21>