title: Effectiveness of 2012-2013 influenza vaccine against influenza-like illness in general population: estimation in a French web-based cohort.
abstract: Most of the methods used for estimating the influenza vaccine effectiveness (IVE) target the individuals who have an influenza-like illness (ILI) rather than virologically-proven influenza and access the healthcare system. The objective of this study was to estimate the 2012-2013 IVE in general French population, using a cohort of volunteers registered on GrippeNet.fr, an online surveillance system for ILI. The IVE estimations were obtained through a logistic regression, and analyses were also performed by focusing on at-risk population of severe influenza, and by varying inclusion period and ILI definition. Overall, 1996 individuals were included in the analyses. The corrected IVE was estimated to 49% (20 to 67) for the overall population, and 32% (0 to 58) for the at-risk population. Three covariables appeared with a significant effect on the occurrence of at least one ILI during the epidemic: the age (P = 0.045), the presence of a child in the household (P<10(-3)), and the frequency of cold/flu (P<10(-3)). Comparable results were found at epidemic peak time in the hypothesis of real-time feed of data. In this study, we proposed a novel, follow-up, web-based method to reveal seasonal vaccine effectiveness, which enables analysis in a portion of the population that is not tracked by the health care system in most VE studies.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale; Paris, France; Université Pierre et Marie Curie-Paris 6; Paris, France.
authors.forename: Marion
authors.initials: M
authors.lastname: Debin
authors.affiliation: Institut National de la Santé et de la Recherche Médicale; Paris, France; Université Pierre et Marie Curie-Paris 6; Paris, France; Institute for Scientific Interchange; Torino, Italy.
authors.forename: Vittoria
authors.initials: V
authors.lastname: Colizza
authors.affiliation: Institut National de la Santé et de la Recherche Médicale; Paris, France; Université Pierre et Marie Curie-Paris 6; Paris, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Blanchon
authors.affiliation: Institut National de la Santé et de la Recherche Médicale; Paris, France; Université Pierre et Marie Curie-Paris 6; Paris, France; Université Versailles Saint Quentin en Yvelines; Versailles, France; Assistance Publique Hopitaux de Paris; Hopital Ambroise Paré; Boulogne Billancourt, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hanslik
authors.affiliation: Institut National de la Santé et de la Recherche Médicale; Paris, France; Université Pierre et Marie Curie-Paris 6; Paris, France.
authors.forename: Clement
authors.initials: C
authors.lastname: Turbelin
authors.affiliation: Institut National de la Santé et de la Recherche Médicale; Paris, France; Université de Corse; Laboratoire de Virologie; Corte, France.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Falchi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D062665:Epidemiological Monitoring; D005260:Female; D005500:Follow-Up Studies; D005602:France / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000276:immunology*; D007251:Influenza, Human / Q000453:epidemiology* / Q000517:prevention & control*; D020407:Internet; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines
keywords: GrippeNet; general population; influenza; vaccine; vaccine effectiveness