Vaccine Effectiveness (VE) vs Symptomatic Disease

Studies

Title: Effectiveness of COVID-19 vaccines against the Omicron (B.1.1.529) variant of concern (2021-12-14)
BioNTech (Pfizer) vs Omicron:

• 2 Dose - 88% VE (2-9wks after dose 2),34-37% VE (15wks)
• 2 Dose + Booster -75.5% VE (2wks after booster)

BioNTech (Pfizer) vs Delta:

• 2 Dose - 63.5% VE (≥25wks after dose 2)
• 2 Dose + Booster - 92.6% VE (2wks after booster)

https://www.medrxiv.org/content/10.1101/2021.12.14.21267615v1

Title: Vaccine effectiveness and duration of protection of Comirnaty, Vaxzevria and Spikevax against mild and severe COVID-19 in the UK (2021-10-06)
BioNTech (Pfizer) vs Delta

• 2 Dose - 69.7% VE (20+ wks after dose 2)

https://www.medrxiv.org/content/10.1101/2021.09.15.21263583v2

Title: Effectiveness of Covid-19 Vaccines against the B.1.617.2 (Delta) Variant (2021-08-12)
BioNTech/Pfizer/BNT162b2 after 2 doses:

• 93.7% VE vs Alpha, 88.0% VE vs Delta

Oxford/AstraZeneca/ChAdOx1 after 2 doses:

• 74.5% VE vs Alpha, 67.0% vs Delta

"Only modest differences in vaccine effectiveness were noted with the delta variant as compared with the alpha variant after the receipt of two vaccine doses."
https://www.nejm.org/doi/full/10.1056/NEJMoa2108891