Moderna COVID-19 Vaccine

The Moderna COVID-19 vaccine is now on Australian shores and will soon be available at community pharmacies. There will be two doses required for the Moderna COVID-19 vaccine, 4 to 6 weeks apart.

What is the Moderna COVID-19 vaccine and how does it work?

The Moderna COVID-19 vaccine is a mRNA vaccine similar to the Pfizer vaccine with only a few technical differences.

It contains the genetic code that instructs the body to make copies of the spike protein which is an important part of the SARS-CoV-2 virus which causes COVID-19. Your immune system then learns to recognise and fight against the SARS-CoV-2 virus. The genetic code is broken down quickly by the body.

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

What is the Moderna vaccine similar to?

The Moderna vaccine shares many characteristics with the Pfizer vaccine with only a few technical differences. As mentioned above, both are mRNAs based on the same chemistry and produce the same spike protein variant.

There are slight differences in the mRNA sequence, both in the spike protein’s genetic code and outside the actual genetic code.

Who should and shouldn’t get vaccinated with the Moderna COVID-19 vaccine?

The Moderna COVID-19 vaccine is approved for people aged 12 years and older.

You should not get an mRNA COVID-19 vaccine if you have had any of the following:

  • a severe allergic reaction (anaphylaxis) or an immediate allergic reaction, even if it was not severe, to any ingredient in an mRNA COVID-19 vaccine (such as polyethylene glycol)
  • a severe or immediate allergic reaction after getting the first dose of an mRNA COVID-19 vaccine, you should not get a second dose of either of the mRNA COVID-19 vaccines (Moderna or Pfizer-BioNTech)
  • myocarditis and/or pericarditis attributed to a previous dose of an mRNA COVID-19 vaccine (i.e. Moderna or Pfizer)
  • any other serious adverse event, that following review by an experienced immunisation provider or medical specialist was attributed to a previous dose of a mRNA COVID-19 vaccine (i.e. Moderna or Pfizer) and without another cause identified

If you have a bleeding disorder or you are taking a blood-thinning medication (anticoagulant), tell your immunisation provider. Your immunisation provider can help determine whether it is safe for you to have an intramuscular injection and help decide the best timing for injection.

How well does the Moderna COVID-19 vaccine work?

Very large clinical trials have shown that the Moderna COVID-19 vaccine is effective in preventing COVID-19 in people aged 12 years and over. Adults who have had two doses of Moderna COVID-19 vaccine have been shown to be about 94% less likely to become ill from COVID-19 than people who have not been vaccinated. The vaccine has been shown to be about 86% effective in people over 65 years of age.

Children aged 12 to 17 years who have had two doses of the Moderna COVID-19 vaccine have been 93% less likely to get symptomatic COVID-19 than those who are unvaccinated.

It is also important to note that the vaccine was also highly effective in clinical trials at preventing COVID-19 among people of diverse age, sex, race, and ethnicity. On top of this, it also proved to be highly effective in clinical trials for those with underlying medical conditions.

Clinical trials are also underway to test Moderna COVID-19 vaccine in children from 6 months of age, however the results of these trials are not yet available.

What to expect after your Moderna COVID-19 vaccination?

You may experience some mild side effects following vaccination. Most side effects last no more than a couple of days and you will recover without any problems.

Common side effects after the Moderna COVID-19 Vaccine include:

  • pain at the injection site
  • tiredness and fatigue
  • headache
  • muscle or joint pain and stiffness
  • fever and chills

Less common side effects after the Moderna COVID-19 Vaccine include:

  • redness or selling at the injection site
  • swelling or tenderness in the armpit
  • nausea (feeling sick) or vomiting
  • enlarged lymph nodes

These side effects are usually mild and start within a day after the vaccination and go away within two or three days. They can be managed by resting and using a pain medicine such as paracetamol or ibuprofen, or a cold compress if needed. Your pharmacist can assist with advice.

A small portion of people have had delayed injection site reactions such as pain, swelling or redness, occurring after 7 days of receiving the vaccine.

If after a few days of the vaccine you have unexpected symptoms or you have an expected side effect listed above that has not gone away, you should seek medical advice from your doctor or healthcare professional. Be sure to tell them that you have recently received the Moderna COVID-19 Vaccine.

Serious reactions such as allergic reactions are extremely rare and usually occur within 15 minutes of receiving your vaccine, which is why you are asked to wait in the pharmacy afterwards. If an allergic reaction occurs, your pharmacist is trained and equipped to deal with this. After you leave the pharmacy, call 000 if you think you are having an allergic reaction and experiencing severe symptoms such as difficulty breathing, wheezing, a fast heartbeat or collapsing.

Myocarditis and pericarditis are very rare side effects that may happen after receiving the Moderna COVID-19 Vaccine. Myocarditis is inflammation of the heart and pericarditis is inflammation of the heart lining. In the rare cases it has occurred, it has been within two weeks of having the vaccine. It occurs more commonly after the second dose of the vaccine and in younger men under 30 years of age. Most cases of myocarditis or pericarditis linked to Moderna COVID-19 vaccine have been mild and recovery has been quick.

You should attend your nearest Emergency Department or call 000 if you have any of the following symptoms, particularly within 1 to 5 days and up to 14 days after vaccination:

  • chest pain, pressure or discomfort
  • rapid, irregular or skipped heart beats
  • fainting
  • shortness of breath or pain with breathing·

How quickly do I get protected?

Protection against COVID-19 starts from about two weeks after the first dose. While one dose may give some protection, it may only last for the short-term. Two doses will give optimal protection and you may not be fully protected until 14 days after second dose.

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

Women who are pregnant or breastfeeding

Pregnant women and adolescents should be routinely offered one of the mRNA-based COVID19 vaccines such as Moderna at any stage of pregnancy. If you are trying to become pregnant you do not need to delay vaccination or avoid becoming pregnant after vaccination. Pregnant women with COVID-19 have an increased risk of severe illness and adverse pregnancy outcomes. Real-world evidence has shown that the Moderna COVID-19 vaccine is safe for pregnant women and breastfeeding women. You can discuss the decision in relation to timing of vaccination with your health professional.

If you are breastfeeding, you can have the Moderna COVID-19 vaccine. You do not need to stop breastfeeding after vaccination.

People with a history of COVID-19

If you have had COVID-19 in the past, tell your immunisation provider. Your provider may advise you to wait for up to six months after recovery before having a COVID-19 vaccine. If you have ongoing illness from COVID-19, discuss the best timing of vaccination with your treating doctor.

What are the ingredients in the Moderna COVID-19 vaccine?

The active ingredient of Moderna COVID-19 Vaccine is Elasomeran (messenger ribonucleic acid or mRNA).

A full list of ingredients, including inactive, is available in the Consumer Medicine Information

People with weakened immune systems

People may have a weakened immune system from a medical condition (e.g. HIV./AIDS or some types of cancer) or from some medicines that suppress their immune system (e.g. corticosteroids or chemotherapy).

It is strongly recommended that people with weakened immune systems to be immunised against COVID-19. As the Moderna COVID-19 vaccine is not a live vaccine, it is safe to use in people with weakened immune systems. Discuss with your health care professional for further advice.

It is possible that vaccines are not as effective in people with weakened immune systems, so it is important to continue other preventive measures such as physical distancing and hand washing after vaccination.


https://www.health.gov.au/resources/publications/covid-19-vaccination-information-on-spikevax-moderna-covid-19-vaccine