title: Striking Similarities in the Presentation and Duration of Illness of Influenza A and B in the Community: A Study Based on Sentinel Surveillance Networks in France and Turkey, 2010-2012.
abstract: Influenza B represents a high proportion of influenza cases in some seasons (even over 50%). The Influenza B study in General Practice (IBGP) is a multicenter study providing information about the clinical, demographic and socio-economic characteristics of patients affected by lab-confirmed influenza A or B. Influenza B patients and age-matched influenza A patients were recruited within the sentinel surveillance networks of France and Turkey in 2010-11 and 2011-12 seasons. Data were collected for each patient at the swab test day, after 9±2 days and, if not recovered, after 28±5 days. It was related to patient's characteristics, symptoms at presentation, vaccination status, prescriptions of antibiotics and antivirals, duration of illness, follow-up consultations in general practice or emergency room. We performed descriptive analyses and developed a multiple regression model to investigate the effect of patients and disease characteristics on the duration of illness. Overall, 774 influenza cases were included in the study: 419 influenza B cases (209 in France and 210 in Turkey) and 355 influenza A cases (205 in France and 150 in Turkey). There were no differences between influenza A and B patients in terms of clinical presentation and number of consultations with a practitioner; however, the use of antivirals was higher among influenza B patients in both countries. The average (median) reported duration of illness in the age groups 0-14 years, 15-64 years and 65+ years was 7.4 (6), 8.7 (8) and 10.5 (9) days in France, and 6.3 (6), 8.2 (7) and 9.2 (6) days in Turkey; it increased with age but did not differ by virus type; increased duration of illness was associated with antibiotics prescription. In conclusion, our findings show that influenza B infection appears not to be milder disease than influenza A infection.
authors.affiliation: Open Rome (Organize and Promote Epidemiological Network), Paris, France; Réseau des GROG, Paris, France.
authors.forename: Jean Marie
authors.initials: JM
authors.lastname: Cohen
authors.affiliation: Open Rome (Organize and Promote Epidemiological Network), Paris, France.
authors.forename: Maria Laura
authors.initials: ML
authors.lastname: Silva
authors.affiliation: Open Rome (Organize and Promote Epidemiological Network), Paris, France.
authors.forename: Saverio
authors.initials: S
authors.lastname: Caini
authors.affiliation: Istanbul University, Istanbul, Turkey.
authors.forename: Meral
authors.initials: M
authors.lastname: Ciblak
authors.affiliation: Open Rome (Organize and Promote Epidemiological Network), Paris, France; Réseau des GROG, Paris, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Mosnier
authors.affiliation: Open Rome (Organize and Promote Epidemiological Network), Paris, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Daviaud
authors.affiliation: GlaxoSmithKline (GSK) Biologicals, Brussels, Belgium.
authors.forename: Gonçalo
authors.initials: G
authors.lastname: Matias
authors.affiliation: Istanbul University, Istanbul, Turkey.
authors.forename: Selim
authors.initials: S
authors.lastname: Badur
authors.affiliation: Virology Department, National Influenza Center, Claude Bernard University Lyon 1, Lyon, France.
authors.forename: Martine
authors.initials: M
authors.lastname: Valette
authors.affiliation: Virology Department, Unit of Molecular Genetics of RNA viruses, National Influenza Center, Pasteur Institute, CNRS UMR3569, Université Paris Diderot Sorbonne Paris Cité, Paris, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Enouf
authors.affiliation: Netherlands Institute for Health Services research (NIVEL), Utrecht, The Netherlands.
authors.forename: John
authors.initials: J
authors.lastname: Paget
authors.affiliation: Royal College of General Practitioners, Surveillance and Research Unit, Birmingham, United Kingdom.
authors.forename: Douglas M
authors.initials: DM
authors.lastname: Fleming
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D009980:Influenza A virus / Q000302:isolation & purification*; D009981:Influenza B virus / Q000302:isolation & purification*; D007251:Influenza, Human / Q000175:diagnosis* / Q000453:epidemiology* / Q000821:virology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018571:Sentinel Surveillance; D013997:Time Factors; D014421:Turkey / Q000453:epidemiology; D055815:Young Adult