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The Moderna Vaccine

The Moderna vaccine was authorized for use in Canada on December 23, 2020. This vaccine is a COVID-19 mRNA vaccine.

What are the ingredients in the Moderna Vaccine?

  • Medicinal Ingredient:
    • mRNA
  • Non-medicinal ingredients:
    • 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC)
    • acetic acid, cholesterol
    • lipid SM-102
    • polyethylene glycol (PEG 2000 DMG 1,2-dimyristol-rac-glycerol,methoxy-polyethyleneglycol)
    • sodium acetate
    • sucrose
    • tromethamine
    • tromethamine hydrochloride
    • water for injection

Do NOT take the Moderna vaccine if you are allergic to any of the ingredients in the vaccine, including polyethylene glycol (PEG). 

PEG is a compound commonly found in laxatives, makeup, skin care products, personal lubricants, toothpastes, contact lens solution, cough syrup as well as an additive in some food and drinks.

Do NOT take the Moderna vaccine if you have had a severe reaction (anaphylaxis) after previous administration of an mRNA COVID-19 vaccine.

Can I receive the vaccine if I am pregnant?

Pregnant individuals are eligible and recommended to be vaccinated as soon as possible, at any stage in pregnancy, as COVID-19 infection during pregnancy can be severe and the benefits of vaccination outweigh the risks. Individuals may choose to receive the vaccine at any time during their pregnancy.

It is recommended, but not required, that pregnant individuals have discussion with their treating health care provider, or with a health care provider familiar with their pregnancy, that includes:

  • a review of the potential risks and benefits of the vaccine,
  • a review of the risk of acquiring a COVID-19 infection during pregnancy,
  • a review of the potential risks /consequences associated with a COVID-19 infection during pregnancy, and
  • an acknowledgment of the limited evidence from clinical trials of COVID-19 vaccines in the pregnant population.  

Please see the COVID-19 Vaccination Recommendations for Special Populations (PDF) for further details on COVID-19 vaccination for pregnant individuals. A letter from a health care provider is not required for vaccination.

The Vaccination in Pregnancy & Breastfeeding Patient Decision-Making Tool can be used by individuals to help make an informed decision about receiving the COVID-19 vaccine.

Additional information and recommendations on COVID-19 vaccines during pregnancy:

Can I receive the Moderna vaccine if I have an autoimmune condition, or I am immunocompromised (due to disease or treatment)?

It is strongly recommended that individuals speak with their health care provider to receive informed counselling about COVID-19 vaccination, including timing of vaccination in relation to therapy for the underlying health condition and/or treatment modification in view of possible decreased vaccine effectiveness with the use of immunosuppressive therapy.

How many doses of the Moderna vaccine will I need? 

You will require 2 doses of the Moderna vaccine for the best protection against COVID-19. The second dose of the vaccine should be received 28 days after the first whenever possible, and the interval between doses may be extended up to 4 months.

After vaccination, how long will it take for protection against COVID-19?

In clinical studies involving about 30 000 individuals, the Moderna COVID-19 vaccine was estimated to be 94.1% effective in preventing symptomatic COVID-19, beginning 14 days after the second dose was administered.  

Variants of concern (VOC) spread more easily from person to person and may cause more severe illness than the original strain of COVID-19. Data regarding the protection that the COVID-19 vaccines offer against variants of concern is continuing to expand. To date, evidence shows that:

  • mRNA COVID-19 vaccines effectiveness is comparable against symptomatic and severe illness due to the B.1.1.7 (Alpha - previously known as the variant first detected in the UK) VOC.
  • mRNA COVID-19 vaccines are 43% effective against symptomatic illness due to the B.1.351 (Beta - previously known as the variant first detected in South Africa) VOC after one dose, and 88% effective after two doses.
  • There is limited data on the efficacy or effectiveness of mRNA vaccines against the P.1 (Gamma – previously known as the variant first detected in Brazil) VOC and P.2 (Zeta) VOI.
  • There is currently insufficient evidence to assess effectiveness of the Moderna COVID-19 vaccine against the 1.617.2 (Delta) VOC.

How long does immunity from the Moderna vaccine last?

Like other COVID-19 vaccines, the length of immunity from the Moderna vaccine remains unknown. Research is ongoing.

For information about third doses of COVID-19 vaccines, refer to the Porcupine Health Unit’s Third Doses of COVID-19 Vaccines webpage.

How is the Moderna vaccine administered?

COVID-19 vaccines are given as an intramuscular (IM) injection into the deltoid muscle (upper arm).

What are the possible side effects?

The side effects are similar to other vaccines and are generally mild to moderate. They include things like pain at the injection site, feeling tired, or feverish. These are common side effects of vaccines, and do not pose a risk to health. With all vaccines, there is a chance of a serious side effect such as an allergy reaction, although these are rare. Speak with your health care provider before vaccination if you have a health condition or a serious allergy.

Is the vaccine safe?

Health Canada has completed a rigorous scientific review of the available medical evidence to assess the safety of the Moderna COVID-19 Vaccine. No major safety concerns have been identified. Find more information on the safety of the vaccine on the Government of Ontario website.

What if I miss my second dose?

If you do not receive your second dose within the recommended timeframe, speak with your health care provider as soon as possible. Effectiveness after two doses is higher than with the first dose, therefore, it remains important to still receive the second dose of vaccine.   

After vaccination

Even after getting your second dose, continue to follow public health measures like wearing a mask, physical distancing and washing your hands often. The vaccine is an additional tool in our fight against COVID-19.  It is unknown how long immunity from the vaccine will last. In addition, not everyone is able to get the vaccine for various reasons. We must continue to follow public health measures to slow the spread of COVID-19. Monitor for symptoms of COVID-19 and get tested if symptoms present. There is preliminary evidence that the Moderna vaccine may reduce asymptomatic infection, but the evidence is insufficient at this time to recommend stopping public health measures after vaccination.

Is Moderna better than other COVID-19 vaccines?

All COVID-19 vaccines are good, and all vaccines will help fight the COVID-19 pandemic.

The authorization of additional vaccines in Canada to fight the pandemic can only help and provide additional support to respond to the pandemic as quickly as possible.

There are several vaccines approved for use in Canada and each report a different efficacy rate. The efficacy of different vaccines cannot be directly compared. Each vaccine was studied in a different clinical trial which were conducted at different times, using different populations and conditions. The authorized COVID-19 vaccines have not been compared in clinical trials.

Having additional vaccines authorized for use in Canada will provide the opportunity to better meet the vaccine dose volume needs so that more people can be vaccinated and protected against COVID-19 sooner.