Sort Through Growing Options for COVID-19 Vaccines

You'll be in a key spot to answer questions about COVID-19 vaccines...as more options become available in Canada.

The new COVID-19 vaccine from Johnson & Johnson/Janssen (Ad26.COV2.S) is the latest to join the fight against the virus...on the heels of the AstraZeneca (ChAdOx1-S) COVID-19 vaccine approval.

These are both "viral vector" COVID-19 vaccines...the products from Pfizer-BioNTech or Moderna are mRNA COVID-19 vaccines.

But Janssen's is the only single-dose option...and can be stored in a fridge rather than a freezer, similar to AstraZeneca's.

Emphasize getting vaccinated with ANY available COVID-19 vaccine when eligible...and help clear up concerns.

Efficacy. Explain that each of these vaccines has at least 85% efficacy at preventing SEVERE COVID-19...such as cases leading to ICU admissions or death.

And growing data suggest these vaccines decrease asymptomatic COVID-19 cases and transmission.

Expect evidence to continue emerging about how vaccine efficacy holds up against viral variants.

For now, advise patients to keep wearing a mask after immunization...and maintain social distancing.

Safety. Media is buzzing over rare reports of blood clots with the AstraZeneca vaccine...but expert review of data shows no increase in overall risk of blood clots compared to the general population.

Health Canada is taking a precautionary approach and updating labelling...to include information about an extremely rare risk of blood clots associated with low platelet levels.

So far, a link between blood clots and the vaccine is still not proven...and the risk of a blood clot or other complications due to COVID-19 infection is far greater.

For now, continue to follow provincial guidance on which patients and age groups are eligible for the AstraZeneca vaccine.

Adverse effects. These are similar overall for the 4 vaccines.

Patients may hear about "COVID arm"...a large, red, itchy reaction around the injection site a week or so after mRNA COVID-19 vaccination.

Explain that this is uncommon and NOT a reason to avoid the second dose. If practical, suggest the second dose in the opposite arm.

Check our chart, COVID-19 Vaccines, for dosing, storage and stability, etc...and details on the pending Novavax COVID-19 vaccine.

Key References

  • https://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2021/75211a-eng.php (3-29-21)
  • https://thrombosiscanada.ca/tc-updated-statement-march-18/ (3-29-21)
  • www.canada.ca/en/public-health/services/immunization/national-advisory-committee-on-immunization-naci/recommendations-use-covid-19-vaccines.html (3-29-21)
  • BMJ 2021;372:n612
  • Lancet 2021;397(10269):99-111
Pharmacist's Letter Canada. March 2021, No. 370415



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