tetano
Editor, Senior Moderator
accine. 2018 Apr 30. pii: S0264-410X(18)30546-2. doi: 10.1016/j.vaccine.2018.04.049. [Epub ahead of print] [h=1]Does consecutive influenza vaccination reduce protection against influenza: A systematic review and meta-analysis.[/h] Bartoszko JJ[SUP]1[/SUP], McNamara IF[SUP]1[/SUP], Aras OAZ[SUP]2[/SUP], Hylton DA[SUP]1[/SUP], Zhang YB[SUP]1[/SUP], Malhotra D[SUP]3[/SUP], Hyett SL[SUP]1[/SUP], Morassut RE[SUP]1[/SUP], Rudziak P[SUP]4[/SUP], Loeb M[SUP]5[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]INTRODUCTION:[/h] Vaccination against influenza on an annual basis is widely recommended, yet recent studies suggest consecutive vaccination may reduce vaccine effectiveness (VE).
[h=4]PURPOSE:[/h] To assess whether when examining the entirety of existing data consecutive influenza vaccination reduces VE compared to current season influenza vaccination.
[h=4]DATA SOURCES:[/h] MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to April 26, 2017; citations of included studies.
[h=4]STUDY SELECTION:[/h] Randomized, controlled trials (RCTs) and observational studies of children, adults and/or the elderly that reported laboratory-confirmed influenza infection over 2 or more consecutive influenza seasons were eligible.
[h=4]DATA EXTRACTION:[/h] Data related to study characteristics, participant demographics, cases of influenza infection by vaccination group and risk of bias assessment was extracted in duplicate.
[h=4]DATA SYNTHESIS:[/h] Five RCTs involving 11,987 participants did not show a significant reduction in VE when participants vaccinated in two consecutive seasons (VE 71%, 95% CI 62-78%) were compared to those vaccinated in the current season (VE 58%, 95% CI 48-66%) (odds ratio [OR] 0.88, 95% CI 0.62-1.26, p = 0.49, I[SUP]2[/SUP] = 39%). Twenty-eight observational studies involving 28,627 participants also did not show a reduction (VE 41%, 95% CI 30-51% compared to VE 47%, 95% CI 39-54%; OR 1.14, 95% CI 0.98-1.32, p = 0.09, I[SUP]2[/SUP] = 63%). Results from subgroup analyses by influenza type/subtype, vaccine type, age, vaccine match and co-morbidity support these findings; however, dose-response results were inconsistent. Certainty in the evidence was assessed to be very low due to unexplained heterogeneity and imprecision.
[h=4]LIMITATIONS:[/h] Included studies with relatively small sample sizes; summary VE and OR estimates were derived from raw and unadjusted data.
[h=4]CONCLUSION:[/h] Available evidence does not support a reduction in VE with consecutive influenza vaccination.
[h=4]FUNDING SOURCE:[/h] CIHR Foundation Grant (PROSPERO: CRD42017059893).
Copyright ? 2018. Published by Elsevier Ltd.
[h=4]KEYWORDS:[/h] Consecutive vaccination; Influenza infection; Influenza vaccine; Meta-analysis; Systematic review; Vaccine effectiveness
PMID: 29724509 DOI: 10.1016/j.vaccine.2018.04.049
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]INTRODUCTION:[/h] Vaccination against influenza on an annual basis is widely recommended, yet recent studies suggest consecutive vaccination may reduce vaccine effectiveness (VE).
[h=4]PURPOSE:[/h] To assess whether when examining the entirety of existing data consecutive influenza vaccination reduces VE compared to current season influenza vaccination.
[h=4]DATA SOURCES:[/h] MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to April 26, 2017; citations of included studies.
[h=4]STUDY SELECTION:[/h] Randomized, controlled trials (RCTs) and observational studies of children, adults and/or the elderly that reported laboratory-confirmed influenza infection over 2 or more consecutive influenza seasons were eligible.
[h=4]DATA EXTRACTION:[/h] Data related to study characteristics, participant demographics, cases of influenza infection by vaccination group and risk of bias assessment was extracted in duplicate.
[h=4]DATA SYNTHESIS:[/h] Five RCTs involving 11,987 participants did not show a significant reduction in VE when participants vaccinated in two consecutive seasons (VE 71%, 95% CI 62-78%) were compared to those vaccinated in the current season (VE 58%, 95% CI 48-66%) (odds ratio [OR] 0.88, 95% CI 0.62-1.26, p = 0.49, I[SUP]2[/SUP] = 39%). Twenty-eight observational studies involving 28,627 participants also did not show a reduction (VE 41%, 95% CI 30-51% compared to VE 47%, 95% CI 39-54%; OR 1.14, 95% CI 0.98-1.32, p = 0.09, I[SUP]2[/SUP] = 63%). Results from subgroup analyses by influenza type/subtype, vaccine type, age, vaccine match and co-morbidity support these findings; however, dose-response results were inconsistent. Certainty in the evidence was assessed to be very low due to unexplained heterogeneity and imprecision.
[h=4]LIMITATIONS:[/h] Included studies with relatively small sample sizes; summary VE and OR estimates were derived from raw and unadjusted data.
[h=4]CONCLUSION:[/h] Available evidence does not support a reduction in VE with consecutive influenza vaccination.
[h=4]FUNDING SOURCE:[/h] CIHR Foundation Grant (PROSPERO: CRD42017059893).
Copyright ? 2018. Published by Elsevier Ltd.
[h=4]KEYWORDS:[/h] Consecutive vaccination; Influenza infection; Influenza vaccine; Meta-analysis; Systematic review; Vaccine effectiveness
PMID: 29724509 DOI: 10.1016/j.vaccine.2018.04.049