title: Influenza-like-illness and clinically diagnosed flu: disease burden, costs and quality of life for patients seeking ambulatory care or no professional care at all.
abstract: This is one of the first studies to (1) describe the out-of-hospital burden of influenza-like-illness (ILI) and clinically diagnosed flu, also for patients not seeking professional medical care, (2) assess influential background characteristics, and (3) formally compare the burden of ILI in patients with and without a clinical diagnosis of flu. A general population sample with recent ILI experience was recruited during the 2011-2012 influenza season in Belgium. Half of the 2250 respondents sought professional medical care, reported more symptoms (especially more often fever), a longer duration of illness, more use of medication (especially antibiotics) and a higher direct medical cost than patients not seeking medical care. The disease and economic burden were similar for ambulatory ILI patients, irrespective of whether they received a clinical diagnosis of flu. On average, they experienced 5-6 symptoms over a 6-day period; required 1.6 physician visits and 86-91% took medication. An average episode amounted to €51-€53 in direct medical costs, 4 days of absence from work or school and the loss of 0.005 quality-adjusted life-years. Underlying illness led to greater costs and lower quality-of-life. The costs of ILI patients with clinically diagnosed flu tended to increase, while those of ILI patients without clinically diagnosed flu tended to decrease with age. Recently vaccinated persons experienced lower costs and a higher quality-of-life, but this was only the case for patients not seeking professional medical care. This information can be used directly to evaluate the implementation of cost-effective prevention and control measures for influenza. In particular to inform the evaluation of more widespread seasonal influenza vaccination, including in children, which is currently considered by many countries.
authors.affiliation: Centre for Health Economics Research & Modelling Infectious Diseases (CHERMID), Vaccine & Infectious Disease Institute (VAXINFECTIO) WHO collaborating Centre, Faculty of Medicine & Health Sciences, University of Antwerp, Antwerp, Belgium.
authors.forename: Joke
authors.initials: J
authors.lastname: Bilcke
authors.affiliation: Centre for General Practice, Primary and Interdisciplinary Care (ELIZA), Faculty of Medicine & Health Sciences, University of Antwerp, Antwerp, Belgium; Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute (VAXINFECTIO) WHO collaborating Centre, Faculty of Medicine & Health Sciences, University of Antwerp, Antwerp, Belgium.
authors.forename: Samuel
authors.initials: S
authors.lastname: Coenen
authors.affiliation: Centre for Health Economics Research & Modelling Infectious Diseases (CHERMID), Vaccine & Infectious Disease Institute (VAXINFECTIO) WHO collaborating Centre, Faculty of Medicine & Health Sciences, University of Antwerp, Antwerp, Belgium; School of Public Health and Community Medicine, Sydney, Australia.
authors.forename: Philippe
authors.initials: P
authors.lastname: Beutels
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000553:Ambulatory Care / Q000706:statistics & numerical data*; D001530:Belgium; D002648:Child; D017281:Cost of Illness; D005260:Female; D006801:Humans; D007252:Influenza Vaccines / Q000276:immunology; D007251:Influenza, Human / Q000175:diagnosis* / Q000188:drug therapy / Q000821:virology; D008297:Male; D008875:Middle Aged; D010342:Patient Acceptance of Health Care; D011788:Quality of Life; D011795:Surveys and Questionnaires; D014611:Vaccination; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines