COVID-19 vaccine effectiveness on variants of concern
Observational studies
Protocol
Our protocol is available on Zenodo here .Last search data: Nov 3, 2021.
The project stopped after this date and the analysis presented include eligible studies up to Nov 3, 2021.
Variants of concern
We identified observational studies assessing vaccine effectiveness on variant from the studies identified by Krause P et al. Lancet 2021 and the process described in our protocol .Vaccine effectiveness is based on direct evidence but also indirect evidence (i.e., variant exposure extrapolated the prevalence of the variant in the population) reported in the manuscript or in secondary sources.
Risk of bias assessment is ongoing and may be missing on the forest plots.
- Studies included (last update: 2022-06-10)
- Forest plots - RNA based vaccine (last update: 2021-12-02)
- Forest plots - Non replicating viral vector (last update: 2021-12-02)
- Forest plots - Inactivated virus (last update: 2021-12-02)
- Forest plots - Any vaccine (last update: 2021-12-02)
- Forest plots - Booster (last update: 2021-11-26)
- Studies included (last update: 2021-12-13)
- Forest plots - RNA based vaccine (last update: 2021-11-12)
- Forest plots - Non replicating viral vector (last update: 2021-11-12)
- Forest plots - Any vaccine (last update: 2021-11-05)
- Studies included (last update: 2021-10-27)
- Forest plots - RNA based vaccine (last update: 2021-10-28)
- Forest plots - Inactivated virus (last update: 2021-10-14)
- Studies included (last update: 2021-11-15)
- Forest plots - RNA based vaccine (last update: 2021-10-21)
- Studies included (last update: 2024-07-27)
- Forest plots - RNA based vaccine (last update: 2021-10-21)
- Forest plots - Non replicating viral vector (last update: 2021-10-21)
Delta
Alpha
Gamma
Beta
Beta-gamma
Studies for variant gamma
| Trial | Design | Variant | Participants | Comparisons | ||||
|---|---|---|---|---|---|---|---|---|
| Type | Intervention 1 | Intervention 2 | Overall risk of bias Highest assessment |
Full description | ||||
|
Hitchings M, Lancet Reg Health Am, 2021 Full text Full text Commentary Commentary Commentary |
Test-negative | Gamma | All healthcare workers, including in hospitals, primary care, general, and specialized units | Inactivated virus | CoronaVac | No vaccine |
Moderate Details |
|
|
Ranzani O, medRxiv, 2021 Full text Commentary Commentary |
Test-negative | Gamma | Adults ≥70 years of age, residents of São Paulo State and who underwent SARS-CoV-2 RT-PCR testing in multiple centers in Brazil | Inactivated virus | CoronaVac | No vaccine |
Serious Details |
|
|
Skowronski D, Clin Infect Dis, 2021 Full text Commentary Commentary |
Test-negative | Gamma | Elderly aged 70 and older in communities in British Colombia, Canada | RNA based vaccine | BNT162b2 or mRNA-1273 | No vaccine |
Serious Details |
|
|
Yassi A, PLoS ONE, 2021 Full text Commentary Commentary |
Cohort | Gamma | Healthcare workers in Vancouver, Canada | RNA based vaccine | BNT162b2 or mRNA-1273 | No vaccine |
Serious Details |
|