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.

Description of primary studies

In this table, we report the main characteristics of the Non randomized studies identified. The risk of bias by domain as well as overall risk of bias reported in the table corresponds to the highest risk of bias for the outcomes assessed for the systematic review.
Trial Design Variant Participants Comparisons
Type Intervention 1 Intervention 2 Overall risk
of bias
Highest assessment
Full description


Amirthalingam G, medRxiv, 2021

Full text
Commentary
Commentary
Test-negative Alpha Healthy adults aged 50-64 years in England Non replicating viral vector ChAdOx1-S No vaccine Extraction in progress

Full description

RNA based vaccine BNT162b2 No vaccine Extraction in progress


Andrews N, medRxiv, 2021

Full text
Commentary
Commentary
Test-negative Delta Adults aged 16 years or older living in England RNA based vaccine mRNA-1273 No vaccine
Moderate
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Moderate
Details
RNA based vaccine BNT162b2 No vaccine
Moderate
Details


Bajema K, MMWR, 2021

Full text
Commentary
Test-negative Delta U.S. veterans hospitalized at five Veterans Affairs Medical Centers (VAMCs) in USA. RNA based vaccine mRNA-1273 No vaccine
Moderate
Details

Full description

RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Moderate
Details
RNA based vaccine BNT162b2 No vaccine
Moderate
Details


Bar-On Y, N Engl J Med, 2021

Full text
Commentary
Cohort Delta Israel residents 60 years of age or older who had been fully vaccinated at least 5 months earlier Booster BNT162b2 booster BNT162b2
Serious
Details

Full description



Barda N, Lancet, 2021

Full text
(21)02249-2/fulltextCommentary
Cohort Delta Individuals, 16 years or older, that received the second vaccine dose at least 5 months ago in Israel Booster BNT162b2 booster BNT162b2
Moderate
Details

Full description



Barlow R, medRxiv, 2021

Full text
Commentary
Commentary
Test-negative Delta Adults (15+ year old) twithout previous SARS-CoV-2 infection hat were tested for SARS-CoV-2 during July 2021 in a single county in USA. RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details
Non replicating viral vector Ad26.COV2.S No vaccine
Serious
Details


Bhattacharya A, Diabetes Metab Syndr, 2021

Full text
Commentary
Cohort Delta Adults attending a COVID-19 testing clinic and hospitalized COVID-19 patients in a single center in India Any COVID-19 vaccine ChAdOx1-S or BBV152 No vaccine
Serious
Details

Full description



Bruxvoort K, medRxiv, 2021

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Commentary
Test-negative Delta Adults members of an integrated health care system (KPSC) in the USA RNA based vaccine mRNA-1273 No vaccine
Moderate
Details

Full description



Bruxvoort K, SSRN, 2021

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Commentary
Commentary
Cohort Delta Adults aged ≥18 years who are members of Kaiser Permanente Southern California in the USA RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description



Chadeau-Hyam M, medRxiv, 2021

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Commentary
Commentary
Cross-sectional Delta Random selection of adults volunteering to provide self-sampled throat and nose swabs in England RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
Any COVID-19 vaccine BNT162b2 or mRNA-1273 or ChAdOx1-S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details
NCT04607941

Charmet T, Lancet Reg Health Eu, 2021

Full text
Commentary
Case-control Beta/Gamma Adults in community with or without prior history of infection in France RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description

NCT04607941

Charmet T, Lancet Reg Health Eu, 2021

Full text
Commentary
Case-control Alpha Adults in France with or without prior history of infection (>2 months previous to index infection) RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description



Chemaitelly H, N Eng J Med, 2021

Full text
Commentary
Test-negative Alpha Adults and children with PCR-confirmed/negative SARS-CoV-2 in Qatar. RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description



Chemaitelly H, N Eng J Med, 2021

Full text
Commentary
Test-negative Delta Adults and children with PCR-confirmed/negative SARS-CoV-2 in Qatar. RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description



Chemaitelly H, Nat. Med., 2021

Full text
Test-negative Beta Mainly working-age adults not vaccinated or receiving at least one dose of the mRNA- 1273 vaccine or completed the two-dose regimen RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description



Chemaitelly H, N Eng J Med, 2021

Full text
Commentary
Test-negative Beta Adults and children with PCR-confirmed/negative SARS-CoV-2 in Qatar. RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description



Chemaitelly H, medRxiv, 2021

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Commentary
Cohort Beta Immunosuppressed kidney transplant recipients in Qatar. RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Moderate
Details

Full description



Chemaitelly H, Nat. Med., 2021

Full text
Test-negative Alpha Mainly working-age adults not vaccinated or receiving at least one dose of the mRNA- 1273 vaccine or completed the two-dose regimen RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description



Chung H, BMJ, 2021

Full text
Commentary
Commentary
Commentary
Test-negative Alpha People with COVID-like symptoms and with no history of COVID-19 tested for SARS-CoV-2 RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Moderate
Details

Full description



Chung H, BMJ, 2021

Full text
Commentary
Commentary
Commentary
Test-negative Beta/gamma People with COVID-like symptoms and with no history of COVID-19 tested for SARS-CoV-2 RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Moderate
Details

Full description



Cohn B, medRxiv, 2021

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Commentary
Commentary
Cohort Delta Adults aged 18 and older including elderly and co-morbidities in all states and territories of USA RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 No vaccine
Serious
Details
Non replicating viral vector Ad26.COV2.S No vaccine
Serious
Details


Corchado-Garcia J, medRxiv, 2021

Full text
Commentary
Cohort Alpha Adults who underwent SARS-CoV-2 polymerase chain reaction (PCR) testing in multiple centers in USA Non replicating viral vector Ad26.COV2.S No vaccine
Serious
Details

Full description



Dagan N, N Engl J Med, 2021

Full text
Commentary
Cohort Alpha Individuals 16 years and older with no previous documented infection with SARS-CoV-2 (PCR) in Israel RNA based vaccine BNT162b2 No vaccine
Moderate
Details

Full description



Dagan N, Nat Med, 2021

Full text
Commentary
Cohort Alpha Pregnant women, aged 16 years or older, in Israel RNA based vaccine BNT162b2 No vaccine
Moderate
Details

Full description



de Gier B, medRxiv, 2021

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Commentary
Commentary
Cohort Delta Adolescents and adults in the Netherlands RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
Any COVID-19 vaccine BNT162b2 or ChAdOx1-S or mRNA-1273 or Ad26.COV2.S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details
Non replicating viral vector Ad26.COV2.S No vaccine
Serious
Details


Elliott P, medRxiv, 2021

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Commentary
Commentary
Cross-sectional Delta Adults aged 18 to 64 years In England, UK. Any COVID-19 vaccine BNT162b2 or mRNA-1273 or ChAdOx1-S No vaccine
Serious
Details

Full description



Flacco M, Vaccines, 2021

mdpi.com/2076-393X/9/6/628Commentary
Cohort Alpha Adults aged 18 and up without previous SARS-CoV-2 infection residing in Pescara, Italy RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
Any COVID-19 vaccine BNT162b2 or mRNA-1273 or ChAdOx1-S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details


Fowlkes A, MMWR, 2021

Full text
Cohort Delta Adults with occupation involving regular direct contact (within three feet) with others, ) Any COVID-19 vaccine BNT162b2 or mRNA-1273 or Ad26.COV2.S No vaccine
Moderate
Details

Full description



Giansante C, Acta Biomed, 2021

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Commentary
Cohort Alpha The staff of the Bologna Health Trust, Emilia Romagna Region, Northern Italy. RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details

Full description



Glampson B, medRxiv, 2021

Full text
Commentary
Cohort Alpha Adults (16 years and older) eligible to be offered a COVID-19 in the UK. Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 No vaccine
Serious
Details


Glatman-Freedman A, Emerg Infect Dis, 2021

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Commentary
Cohort Delta Adolescents 12–15 years of age with no history of COVID-19 in Israel RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description



Goldberg Y, medRxiv, 2021

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Commentary
Commentary
Cohort Delta Elderly ages 60 and up who became fully vaccinated between January 16-31, 2021 and without previous SARS-CoV-2 infection in multiple centres in Israel RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description



Goldshtein I, JAMA, 2021

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Commentary
Commentary
Cohort Alpha Pregnant women with no history of SARS-CoV-2 registered in a a large state-mandated health care organization in Israel RNA based vaccine BNT162b2 No vaccine
Moderate
Details

Full description



Grannis S, MMWR, 2021

Full text
Commentary
Test-negative Delta Adults hospitalized with COVID-19-like illness in 9 states in multiple centres in USA RNA based vaccine mRNA-1273 No vaccine
Moderate
Details

Full description

Any COVID-19 vaccine BNT162b2 or mRNA-1273 or Ad26.COV2.S No vaccine
Moderate
Details
RNA based vaccine BNT162b2 No vaccine
Moderate
Details
Non replicating viral vector Ad26.COV2.S No vaccine
Moderate
Details


Griffin J, MMWR, 2021

Full text
Commentary
Cohort Delta All aged 12 and up residents of Los Angeles County in multiple centres in USA Any COVID-19 vaccine BNT162b2 or mRNA-1273 or Ad26.COV2.S No vaccine
Critical
Details

Full description



Haas E, Lancet, 2021

Full text
Commentary
Cohort Alpha Adults (16 years and older) with no history of COVID-19 in Israel RNA based vaccine BNT162b2 No vaccine
Serious
Details

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

Full description

ISRCTN, number 39557.

Hyams C, Lancet Infect Dis, 2021

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Commentary
Test-negative Alpha Adults >80 years who were admitted to hospital in two NHS trusts in Bristol, UK with signs and symptoms of respiratory disease(test-positive/negative) Non replicating viral vector ChAdOx1-S No vaccine
Moderate
Details

Full description

RNA based vaccine BNT162b2 No vaccine
Moderate
Details


Israeli Ministry of Health, *, 2021

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Cohort Delta All residents aged 16 years and older in Israel RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description



Kang M, SSRN, 2021

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Commentary
Commentary
Commentary
Cohort Delta Close contacts of confirmed COVID cases during an outbreak in China Inactivated virus HB02 or WIV04 or CoronaVac or BICV No vaccine
Serious
Details

Full description



Kim S, J Infect Dis, 2021

Full text
Commentary
Test-negative Alpha Adolescents and adults with COVID-like symptoms at 5 centers in the USA. RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details

Full description



Layan M, medRxiv, 2021

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Cohort Alpha Household members close contact of an HCW index case RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description



Lefevre B, medRxiv, 2021

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Commentary
Cohort Beta Adults including elderly in 5 centres in France. RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description



Li N-X, Emerg Microbes Infec, 2021

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Commentary
Test-negative Delta Adults aged 18-59 years undergoing PCR testing in China. Inactivated virus HB02 or WIV04 or CoronaVac No vaccine
Serious
Details

Full description



Lin D, medRxiv, 2021

Full text
Commentary
Commentary
Cohort Delta Residents of North Carolina, USA RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description

Non replicating viral vector Ad26.COV2.S No vaccine
Serious
Details


Liu C, medRxiv, 2021

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Commentary
Commentary
Cohort Delta Adults including elderly and co-morbidities with no history of COVID-19 in multiple centres in New York, USA RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details

Full description



Lopez Bernal J, BMJ, 2021

Full text
Commentary
Commentary
Test-negative Alpha Adults aged 70 years and older who reported symptoms of COVID-19 Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 No vaccine
Serious
Details


Lopez J, N Engl J Med, 2021

Full text
Commentary
Test-negative Alpha Data on all symptomatic sequenced cases of COVID-19 in England Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details

Full description

Any COVID-19 vaccine BNT162b2 or ChAdOx1-S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details


Lopez J, N Engl J Med, 2021

Full text
Commentary
Test-negative Delta Data on all symptomatic sequenced cases of COVID-19 in England Non replicating viral vector ChAdOx1-S No vaccine
Moderate
Details

Full description

Any COVID-19 vaccine BNT162b2 or ChAdOx1-S No vaccine
Moderate
Details
RNA based vaccine BNT162b2 No vaccine
Moderate
Details


Lumley S, Clin Infect Dis, 2021

Full text
Commentary
Commentary
Cohort Alpha Staff at 4 hospitals and associated facilities in Oxfordshire, UK. Any COVID-19 vaccine BNT162b2 or ChAdOx1 No vaccine
Serious
Details

Full description



Manley HJ, medRxiv, 2021

ttps://www.medrxiv.org/content/10.1101/2021.09.24.21264081v1Commentary
Commentary
Cohort Delta Adult maintenance dialysis (home and in center) without known prior COVID-19 infection treated at Dialysis Clinic, Inc. in USA. Any COVID-19 vaccine BNT162b2 or mRNA-1273 or Ad26.COV2.S No vaccine
Serious
Details

Full description

Vaccine vs vaccine BNT162b2 mRNA-1273
Serious
Details
Vaccine vs vaccine Ad26.COV2.S mRNA-1273
Serious
Details


Marti-nez Baz I, Euro surveillance, 2021

Full text
Commentary
Cohort Delta Close contacts of COVID-19 cases from 1 April to 31 August 2021 in Navarre, Spain. RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details
Non replicating viral vector Ad26.COV2.S No vaccine
Serious
Details


McKeigue P, medRxiv, 2021

Full text
Commentary
Commentary
Case-control Alpha Population of Scotland Any COVID-19 vaccine BNT162b2 or mRNA-1273 or ChAdOx1-S No vaccine
Serious
Details

Full description



McKeigue P, medRxiv, 2021

Full text
Commentary
Commentary
Case-control Delta Population of Scotland Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details


Morgan JA, Obstet Gynecol, 2021

Full text
Commentary
Cohort Delta Pregnant women in Louisiana, USA Any COVID-19 vaccine BNT162b2 or mRNA-1273 or Ad26.COV2.S No vaccine
Serious
Details

Full description



Murugesan M, SSRN, 2021

Full text
Commentary
Commentary
Cohort Delta Health care workers without previous COVID-19 infection at a single center in Vellore, India. Any COVID-19 vaccine ChAdOx1-S or BBV152 No vaccine
Serious
Details

Full description



Nanduri S, MMWR, 2021

Full text
Commentary
Cohort Delta Residents at 14,917 nursing homes in the USA RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details


Nasreen S, medRxiv, 2021

Full text
Full text
Commentary
Commentary
Test-negative Alpha Symptomatic community-dwelling individuals aged ≥16 years with no history of SARS-CoV-2 infection in Canada RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details


Nasreen S, medRxiv, 2021

Full text
Commentary
Commentary
Commentary
Test-negative Beta/Gamma Symptomatic community-dwelling individuals aged ≥16 years with no history of SARS-CoV-2 infection in Ontario, Canada RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details


Nasreen S, medRxiv, 2021

Full text
Full text
Commentary
Commentary
Test-negative Delta Symptomatic community-dwelling individuals aged ≥16 years with no history of SARS-CoV-2 infection in Canada RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details


Nordstrom P, SSRN, 2021

Full text
Commentary
Commentary
Cohort Delta General population including co-morbidities in Sweden. RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
Any COVID-19 vaccine BNT162b2 or mRNA-1273 or ChAdOx1-S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details
Heterologous 1 ChAdOx1-S + 1 BNT162b2 OR 1 mRNA-1273 No vaccine
Serious
Details


Nunes B, medRxiv, 2021

Full text
Commentary
Commentary
Cohort Delta Older adults aged 65 to 79 without previous SARS-CoV-2 infection living in the community in mainland Portugal RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details

Full description



Patalon T, medRxiv, 2021

Full text
Commentary
Commentary
Test-negative Delta Aged 40 and up Maccabi Healthcare Services members in multiple centres in Israel Booster BNT162b2 booster BNT162b2
Moderate
Details

Full description



Pilishvili T, NEJM, 2021

Full text
Commentary
Test-negative Alpha Health care personnel without previous SARS-CoV-2 infection at 33 centers in USA. RNA based vaccine mRNA-1273 No vaccine
Moderate
Details

Full description

RNA based vaccine BNT162b2 No vaccine
Moderate
Details


Polinski J, medRxiv, 2021

Full text
Commentary
Commentary
Cohort Delta Adults including elderly and co-morbidities with no history of COVID-19 in multiple centres throughout the USA Non replicating viral vector Ad26.COV2.S No vaccine
Serious
Details

Full description

ISRCTN21086382

Pouwels K, Nat Med, 2021

Full text
Full text
Commentary
Commentary
Cohort Delta Adults from households randomly selected across the UK. RNA based vaccine mRNA-1273 No vaccine
Moderate
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Moderate
Details
RNA based vaccine BNT162b2 No vaccine
Moderate
Details
ISRCTN21086382

Pouwels K, Nat Med, 2021

Full text
Full text
Commentary
Commentary
Cohort Alpha Adults from households randomly selected across the UK. RNA based vaccine mRNA-1273 No vaccine
Moderate
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Moderate
Details
RNA based vaccine BNT162b2 No vaccine Extraction in progress


Pramod S, medRxiv, 2021

Full text
Commentary
Commentary
Test-negative Delta Health care workers at a single center in India Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details

Full description



Puranik A, medRxiv, 2021

Full text
Commentary
Commentary
Cohort Alpha Adults who underwent SARS-CoV-2 polymerase chain reaction (PCR) testing at the Mayo Clinic and hospitals affiliated with the Mayo Clinic Health S RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

RNA based vaccine mRNA-1273 BNT162b2
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details


Puranik A, medRxiv, 2021

Full text
Commentary
Commentary
Cohort Delta Adults who underwent SARS-CoV-2 polymerase chain reaction (PCR) testing in multiple centers in USA RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Vaccine vs vaccine mRNA-1273 BNT162b2
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
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

Full description



Ranzani OT, medRxiv, 2021

Full text
Test-negative Delta RT-PCR from adults residing in Mato-Grosso do Sul Non replicating viral vector Ad26.COV2.S No vaccine
Moderate
Details

Full description



Regev-Yochay G, Lancet Reg Health, 2021

Full text
Cohort Alpha Health care workers who have had a possible or confirmed exposure to a SARS-CoV-2-infected person and/or have any COVID-19-associated symptom RNA based vaccine BNT162b2 No vaccine
Serious
Details

Full description



Robles-Fontan M, medRxiv, 2021

Full text
Commentary
Commentary
Cohort Delta General population of Puerto Rico aged 12 years and older RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 No vaccine
Serious
Details
Non replicating viral vector Ad26.COV2.S No vaccine
Serious
Details


Rosenberg E, MMWR, 2021

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Full text
Commentary
Cohort Delta Adults aged ≥18 years residing in New York state in multiple centres in USA Any COVID-19 vaccine BNT162b2 or mRNA-1273 or Ad26.COV2.S No vaccine
Serious
Details

Full description



Self WH, MMWR, 2021

Full text
Test-negative Delta Adults hospitalized with COVID-19 like illness without Immunocompromising conditions living in United States, RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 No vaccine
Serious
Details
Non replicating viral vector Ad26.COV2.S No vaccine
Serious
Details


Seppala E, Euro Surveill, 2021

Full text
Commentary
Cohort Delta All adults aged 18 years or older with no prior SARS-CoV-2 infection with a national identification number registered in multiple centres in Norway RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details

Full description



Seppala E, Euro Surveill, 2021

Full text
Commentary
Cohort Alpha All adults aged 18 years or older with no prior SARS-CoV-2 infection with a national identification number registered in multiple centres in Norway RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details

Full description



Sheikh A, Lancet, 2021

Full text
Commentary
Test-negative Delta People of all ages tested for COVID-19 by RT-PCR in Scotland Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 No vaccine
Serious
Details


Sheikh A, Lancet, 2021

Full text
Commentary
Test-negative Alpha People of all ages tested for COVID-19 by RT-PCR in Scotland Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 No vaccine
Serious
Details


Singh C, Epidemiol Infect, 2021

Full text
Commentary
Case-control Delta Adults aged 45 and up in a single centre in India Any COVID-19 vaccine ChAdOx1-S or BBV152 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
Inactivated virus BBV152 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

Full description



Skowronski D, Clin Infect Dis, 2021

Full text
Commentary
Commentary
Test-negative Alpha Elderly aged 70 and older in communities in British Colombia, Canada RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details

Full description



Skowronski DM, medRxiv, 2021

Full text
Commentary
Commentary
Test-negative Delta SARS-CoV-2 test-positive cases and test-negative controls 18 years and over residing in British Columbia, Canada RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details
Heterologous 1 ChAdOx-S + 1 BNT162b2 OR 1 mRNA-1273 No vaccine
Serious
Details
Heterologous 1 BNT162b2 + 1 mRNA-1273 No vaccine
Serious
Details


Skowronski DM, medRxiv, 2021

Full text
Commentary
Commentary
Test-negative Delta SARS-CoV-2 test-positive cases and test-negative controls 18 years and over residing in Quebec, Canada RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details
Heterologous 1 ChAdOx-S + 1 BNT162b2 OR 1 mRNA-1273 No vaccine
Serious
Details
Heterologous 1 BNT162b2 + 1 mRNA-1273 No vaccine
Serious
Details


Stowe J, PHE Publishing, 2021

Full text
Commentary
Test-negative Delta Symptomatic COVID-19 patients Non replicating viral vector ChAdOx1-S No vaccine
Moderate
Details

Full description

Any COVID-19 vaccine BNT162b2 or ChAdOx1-S No vaccine
Moderate
Details
RNA based vaccine BNT162b2 No vaccine
Moderate
Details


Tang P, medRxiv, 2021

Full text
Commentary
Commentary
Test-negative Delta Resident population in multiple centres in Qatar RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details
NCT04848584

Tartof S, Lancet, 2021

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(21)02183-8/fulltext; Full text
Commentary
Commentary
Commentary
Cohort Delta Kaiser Permanente Southern California healthcare system members aged 12 and up in multiple centres in USA RNA based vaccine BNT162b2 No vaccine
Serious
Details

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Tenforde M, MMWR, 2021

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Commentary
Cohort Alpha Hospitalized adults at 21 centers in the USA RNA based vaccine mRNA-1273 No vaccine Extraction in progress

Full description

RNA based vaccine BNT162b2 or mRNA-1273 No vaccine Extraction in progress
RNA based vaccine BNT162b2 No vaccine
Serious
Details


Tenforde M, MMWR, 2021

Full text
Commentary
Cohort Delta Hospitalized adults at 21 centers in the USA RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details

Full description



Tenforde M, Clin Infect Dis, 2021

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Commentary
Commentary
Test-negative Alpha Hospitalized adults at 18 centers in the USA. RNA based vaccine mRNA-1273 No vaccine
Serious
Details

Full description

RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details
RNA based vaccine BNT162b2 No vaccine
Serious
Details


Thiruvengadam R, SSRN, 2021

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Commentary
Commentary
Test-negative Delta Individuals attending for RT-PCR testing for suspected SARS-CoV-2 infection at 2 centers in India Non replicating viral vector ChAdOx1-S No vaccine
Serious
Details

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Thompson M, N Engl J Med, 2021

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Commentary
Commentary
Commentary
Test-negative Alpha Adults ≥50 years with Covid-19–like illness at multiple sites in the USA RNA based vaccine mRNA-1273 No vaccine
Moderate
Details

Full description

RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Moderate
Details
RNA based vaccine BNT162b2 No vaccine
Moderate
Details
Non replicating viral vector Ad26.COV2.S No vaccine
Moderate
Details


Vaishya R, SSRN, 2021

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Commentary
Commentary
Cohort Delta Vaccinated healthcare workers in 43 hospitals in 24 Indian cities Vaccine vs vaccine ChAdOx1-S BBV152
Serious
Details

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Yassi A, PLoS ONE, 2021

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Commentary
Commentary
Cohort Gamma Healthcare workers in Vancouver, Canada RNA based vaccine BNT162b2 or mRNA-1273 No vaccine
Serious
Details

Full description