Efficacy

Pfizer-BioNTech Vaccine

• First dose efficacy of 85% (95% CI 66-93%) in preventing COVID-19 within 11-21 days after vaccination
• Second dose efficacy 95% (CI 90-97%) 7 days after vaccination

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Moderna Vaccine

• First dose efficacy of 94% (95% CI 76-99%) starting 14 days after vaccination
• Second dose efficacy 94.1% 2 weeks after vaccination
• May be slightly less effective (86.4%; 95% CI 61.4%-95.5%) in older adults 65+

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AstraZeneca-Oxford Vaccine

• First dose efficacy of 64.1% (95% CI 50.5-73.9%) against symptomatic COVID-19 21 days or more after vaccination with one standard dose
• Second dose efficacy of 70.4% (95% CI 54.8-80.6%) across two dosing regimens (low dose [LD]+ standard dose [SD]; SD + SD)
• Second dose efficacy of 90% (95% CI 67.4-97%) in LD + SD group
• Second dose efficacy of 62.1% (95% CI 41-75.7%) in SD + SD group
  

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Sources

• ‍Rollout Strategy for the COVID-19 Pfizer-BioNTech COVID-19 Vaccine in Ontario
• Moderna COVID Vaccine Product Monograph
• Pfizer-BioNTech COVID Vaccine Product Monograph
• Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK
• Information for Healthcare Professionals on COVID-19 Vaccine AstraZeneca

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Side Effects

Pfizer-BioNTech

Injection site pain (84.1%), fatigue (62.9%), headache (55.1%), muscle pain (38.3%), chills (31.9%), joint pain (23.6%) and fever (14.2%) - all usually mild or moderate in intensity

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Moderna

Injection site pain (92.0%), fatigue (70.0%), headache (64.7%), myalgia (61.5%), arthralgia (46.4%), chills (45.4%), nausea/vomiting (23.0%), axillary swelling/tenderness (19.8%), fever (15.5%), swelling at the injection site (14.7%), and erythema at the injection site (10.0%)

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AstraZeneca-Oxford

• Very common (>10%): tenderness, pain, warmth, redness, itching, swelling or bruising where the injection is given, generally feeling unwell, fatigue, chills or feeling feverish, headache, nausea, joint pain or muscle aches
• Common (10%): a lump at the injection site, fever, vomiting, flu-like symptoms (e.g. high temperature, sore throat, runny nose, cough and chills)
• Uncommon (1%): feeling dizzy, decreased appetite, abdominal pain, enlarged lymph nodes, excessive sweating, itchy skin, or rash.
• In clinical trials there were very rare reports of events associated with inflammation of the nervous system, which may cause numbness, pins and needles, and/or loss of feeling. However, it is not confirmed whether these events were due to the vaccine.

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Sources

• Pfizer-BioNTech COVID Vaccine Product Monograph
• Moderna COVID Vaccine Product Monograph
• Information for UK recipients on COVID 19 Vaccine AstraZeneca
  

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