Astra-Zeneca Vaccine

What you need to know about the AstraZeneca COVID-19 vaccine.

Although the AstraZeneca COVID-19 vaccine is well known on the market, we’re sure you have a few questions. It’s great to be informed, and we’ve put together some helpful FAQs to help.

The AstraZeneca COVID-19 vaccine has gone through rigorous evaluation and approval processes, and both the Therapeutic Goods Administration (TGA) and the Australian Technical Advisory Group for Immunisation (ATAGI) recommends the AstraZeneca COVID-19 vaccine for people:

  • aged 60 and over
  • aged 18 to 59 in outbreak areas if they do not have immediate access to Comirnaty (Pfizer) or Spikevax (Moderna).

If you are aged 18 to 59, you can choose to get protected with the AstraZeneca COVID-19 vaccine:

  • following an assessment by a qualified health professional such as a pharmacist
  • if you provide verbal or written consent.

Read on to learn more about the AstraZeneca COVID-19 vaccination, and if you still have questions, you can visit the Department of Health website at or consult your local community pharmacist or other trusted healthcare provider.

Frequently Asked Questions

The AstraZenaca COVID-19 vaccine is available at local community pharmacies. You need 2 doses of the AstraZeneca COVID-19 vaccine, given 4 to 12 weeks apart. You may not be fully protected against COVID-19 until 7 to 14 days after your second dose. Most people have their second dose 12 weeks after their first for optimal effectiveness, but it can be less time in certain situations.

This vaccine, like the other COVID-19 vaccines, will protect you from getting severely ill or dying if you get COVID-19.

The vaccine trains your immune system to recognise and clear out the virus, before it makes you seriously ill. Your body's immune system builds this protection over time.

The virus that causes COVID-19 (called SARS-CoV-2) has spikes of protein on each viral particle. These spike proteins allow the virus to attach to cells and cause disease.

If exposed to the Covid-19 virus, the vaccine helps the body to:

  • recognise these spike proteins as a threat
  • fight the coronavirus that has these spike proteins.

ATAGI recommends the AstraZeneca COVID-19 vaccine for people aged 60 years and above, or between 18-59 years of age if the Pfizer or Moderna vaccines are not readily available.

The AstraZeneca COVID-19 vaccine should not be used in the following circumstances:

  • anaphylaxis after a previous dose of AstraZeneca COVID-19 vaccine
  • anaphylaxis to any component of the AstraZeneca COVID-19 vaccine, including polysorbate 80
  • history of capillary leak syndrome
  • thrombosis with thrombocytopenia occurring after a previous dose of AstraZeneca COVID-19 vaccine
  • any other serious adverse event, that following review by an experienced immunisation provider or medical specialist was attributed to a previous dose of the AstraZeneca COVID-19 vaccine.

ATAGI have also advised that people with a history of one of the following specific blood conditions should not receive the AstraZeneca COVID-19 vaccine:

  • cerebral venous sinus thrombosis (CVST)
  • heparin-induced thrombocytopenia (HIT)
  • idiopathic splanchnic (mesenteric, portal and splenic) venous thrombosis
  • anti-phospholipid syndrome with thrombosis.

The AstraZeneca vaccine does not contain any live virus, and it cannot give you COVID-19.

It contains the genetic code for an important part of the COVID (SARS-CoV-2) virus called the spike protein. This code is inserted into a harmless weakened carrier virus (an adenovirus), which brings it into your cells. Your body then makes copies of the spike protein, and your immune system learns to recognise these as foreign and fights the COVID virus. The adenovirus has been modified so that it cannot replicate once it is inside cells. This means it cannot spread to other cells and cause infection.

It is not recommended to take over the counter medicines before receiving a vaccination for the purpose of preventing potential side effects. You should continue to take prescribed medication unless advised by your medical practitioner.

All COVID-19 vaccines in Australia offer high levels of immunity. The AstraZeneca COVID-19 vaccine has undergone and registered evidence from clinical trials which illustrate its successful results. People who had two doses of the AstraZeneca COVID-19 vaccine were about 62-70 per cent less likely to get COVID-19 than people who did not get the vaccine.

Protection against COVID-19 starts from about 3 weeks after the first dose of the AstraZeneca COVID-19 vaccine. While one dose may give some protection, two doses are needed for optimal protection. The second dose boosts antibody levels and is likely to prolong the duration of protection. The vaccine appears to be more effective when people have a longer interval between the 2 doses. This is why it is better to receive the 2 doses about 12 weeks apart.

No vaccine is 100 per cent effective, so it is possible that you can still get sick from COVID-19 after vaccination.

The AstraZeneca COVID-19 vaccine is safe and effective, using an inactivated chimpanzee adenovirus vaccine vector. This is a harmless, weakened adenovirus that usually causes the common cold in chimpanzees.

The adenovirus vaccine vector, known as ChAdOx1, was chosen as a suitable vaccine technology for a COVID (SARS-CoV-2) vaccine as it has been shown to generate a strong immune response from one dose in other vaccines.

It has been genetically changed so that it is impossible for it to grow in humans.

Chimpanzee adenoviral vectors are a very well-studied vaccine type, having been used safely in thousands of subjects.

The AstraZeneca COVID-19 Vaccine contains the following active ingredients: Inactivated adenovirus ChAdOx1 - S * 5x1010 viral particles (vp) per 0.5ml dose.

Other inactive ingredients include histidine, histidine hydrochloride monohydrate, sodium chloride, magnesium chloride hexahydrate, disodium edetate, sucrose, ethanol absolute, polysorbate 80 and water for injections.

Similarly to the other approved COVID-19 vaccines, most side effects of the AstraZeneca COVID-19 vaccine are mild to moderate in nature and resolve within a few days.

Common side effects after the AstraZeneca COVID-19 vaccine include:

  • pain, swelling, tenderness, redness or itching at the injection site
  • tiredness
  • headache
  • muscle pain
  • nausea (feeling sick)
  • fever and chills
  • feeling unwell
  • joint pain

Less common side effects after AstraZeneca COVID-19 vaccine include:

  • enlarged lymph nodes
  • pain in limb
  • dizziness
  • decreased appetite
  • stomach pain

Serious reactions such as anaphylactic allergic reactions are extremely rare and usually occur within 15 minutes of receiving a vaccine. This is why you are asked to wait in the pharmacy after your vaccination. Your pharmacist is trained to manage any rare allergic reaction should it happen.

Thrombosis with thrombocytopenia syndrome (TTS) is a very rare immune response that may happen after receiving the AstraZeneca COVID-19 vaccine. It involves blood clotting (thrombosis) in different parts of the body and bleeding due to low platelet levels (thrombocytopenia). People with this condition can become unwell and may need to go to hospital. This condition can lead to long-term disability, and even death. TTS is treatable if detected early and most people make a full revery.

There has been a link established between the AstraZeneca COVID-19 vaccine and a very rare but serious side effect called thrombosis with thrombocytopenia syndrome (TTS) . It is currently estimated to affect about 1-2 per 100,000 people who receive the AstraZeneca COVID-19 vaccine. For those under 60 years of age, the rate is estimated to be higher, about 2-3 per 100,000 people.

TTS is different from general clotting conditions such as deep vein thrombosis (DVT) or pulmonary embolism (PE).

Blood clots are common and not all types of blood clot that occur after vaccination will be linked to the vaccine.

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