2024
Effectiveness of the fourth dose of COVID-19 vaccines against severe COVID-19 among adults 40 years or older in Brazil: a population-based cohort study
Neto F, Hitchings M, Amin A, de França G, Lind M, Torres M, Tsuha D, de Oliveira R, Cummings D, Dean N, Andrews J, Ko A, Croda J, Ranzani O. Effectiveness of the fourth dose of COVID-19 vaccines against severe COVID-19 among adults 40 years or older in Brazil: a population-based cohort study. The Lancet Regional Health - Americas 2024, 34: 100755. PMID: 38737773, PMCID: PMC11087726, DOI: 10.1016/j.lana.2024.100755.Peer-Reviewed Original ResearchSevere COVID-19Cohort ACohort B.Cohort BTwo-doseMRNA vaccinesPrimary outcomeBooster dose effectivenessCOVID-19 outcomesPopulation-based cohort studyDose of COVID-19 vaccinePopulation-based cohortPopulation-based cohort of individualsCOVID-19 vaccine dosesSevere COVID-19 outcomesFollow-upCohort studyMRNA-basedVaccine doseCohort of individualsVaccine effectivenessVaccine combinationsDoseLower hazardCohort
2022
Change in covid-19 risk over time following vaccination with CoronaVac: test negative case-control study
Hitchings MDT, Ranzani OT, Lind ML, Dorion M, D'Agostini TL, de Paula RC, de Paula OFP, de Moura Villela EF, Scaramuzzini Torres MS, de Oliveira SB, Schulz W, Almiron M, Said R, de Oliveira RD, Vieira da Silva P, de Araújo WN, Gorinchteyn JC, Dean NE, Andrews JR, Cummings DAT, Ko AI, Croda J. Change in covid-19 risk over time following vaccination with CoronaVac: test negative case-control study. The BMJ 2022, 377: e070102. PMID: 35697361, PMCID: PMC9189440, DOI: 10.1136/bmj-2022-070102.Peer-Reviewed Original ResearchConceptsSymptomatic COVID-19Negative case-control studyCase-control studyHospital admissionOdds ratioCOVID-19Series completionCovid-19 related hospital admissionReverse transcription polymerase chain reaction testingTranscription polymerase chain reaction testingSevere COVID-19 outcomesSARS-CoV-2 infectionPolymerase chain reaction testingInactivated whole virus vaccineDoses of CoronaVacAcute respiratory illnessTest-negative controlsWhole virus vaccineRelated hospital admissionsHealthcare worker statusConditional logistic regressionCOVID-19 outcomesCOVID-19 symptomsMunicipality of residenceSARS-CoV-2
2021
Effectiveness of ChAdOx1 vaccine in older adults during SARS-CoV-2 Gamma variant circulation in São Paulo
Hitchings MDT, Ranzani OT, Dorion M, D’Agostini T, de Paula RC, de Paula OFP, de Moura Villela EF, Torres MSS, de Oliveira SB, Schulz W, Almiron M, Said R, de Oliveira RD, Silva PV, de Araújo WN, Gorinchteyn JC, Andrews JR, Cummings DAT, Ko AI, Croda J. Effectiveness of ChAdOx1 vaccine in older adults during SARS-CoV-2 Gamma variant circulation in São Paulo. Nature Communications 2021, 12: 6220. PMID: 34711813, PMCID: PMC8553924, DOI: 10.1038/s41467-021-26459-6.Peer-Reviewed Original ResearchConceptsSingle doseOxford-AstraZeneca COVID-19 vaccineTest-negative case-control studySevere COVID-19 outcomesCOVID-19COVID-19-related deathsTwo-dose scheduleTwo-dose regimenCase-control studyCOVID-19 outcomesInter-dose intervalCOVID-19 hospitalizationCOVID-19 vaccineSARS-CoV-2ChAdOx1 vaccinePrimary endpointSecondary endpointsFirst doseSecond doseHigh prevalenceElderly individualsElderly populationVariant prevalenceVaccine supplyHospitalization