title: Longitudinal study of infectious intestinal disease in the UK (IID2 study): incidence in the community and presenting to general practice.
abstract: OBJECTIVE
  To estimate, overall and by organism, the incidence of infectious intestinal disease (IID) in the community, presenting to general practice (GP) and reported to national surveillance.
  
  
  METHODS
  Prospective, community cohort study and prospective study of GP presentation conducted between April 2008 and August 2009.
  
  
  METHODS
  Eighty-eight GPs across the UK recruited from the Medical Research Council General Practice Research Framework and the Primary Care Research Networks.
  
  
  METHODS
  6836 participants registered with the 88 participating practices in the community study; 991 patients with UK-acquired IID presenting to one of 37 practices taking part in the GP presentation study.
  
  
  METHODS
  IID rates in the community, presenting to GP and reported to national surveillance, overall and by organism; annual IID cases and GP consultations by organism.
  
  
  RESULTS
  The overall rate of IID in the community was 274 cases per 1000 person-years (95% CI 254 to 296); the rate of GP consultations was 17.7 per 1000 person-years (95% CI 14.4 to 21.8). There were 147 community cases and 10 GP consultations for every case reported to national surveillance. Norovirus was the most common organism, with incidence rates of 47 community cases per 1000 person-years and 2.1 GP consultations per 1000 person-years. Campylobacter was the most common bacterial pathogen, with a rate of 9.3 cases per 1000 person-years in the community, and 1.3 GP consultations per 1000 person-years. We estimate that there are up to 17 million sporadic, community cases of IID and 1 million GP consultations annually in the UK. Of these, norovirus accounts for 3 million cases and 130,000 GP consultations, and Campylobacter is responsible for 500,000 cases and 80,000 GP consultations.
  
  
  CONCLUSIONS
  IID poses a substantial community and healthcare burden in the UK. Control efforts must focus particularly on reducing the burden due to Campylobacter and enteric viruses.
authors.affiliation: Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK. clarence.tam@lshtm.ac.uk
authors.forename: Clarence C
authors.initials: CC
authors.lastname: Tam
authors.forename: Laura C
authors.initials: LC
authors.lastname: Rodrigues
authors.forename: Laura
authors.initials: L
authors.lastname: Viviani
authors.forename: Julie P
authors.initials: JP
authors.lastname: Dodds
authors.forename: Meirion R
authors.initials: MR
authors.lastname: Evans
authors.forename: Paul R
authors.initials: PR
authors.lastname: Hunter
authors.forename: Jim J
authors.initials: JJ
authors.lastname: Gray
authors.forename: Louise H
authors.initials: LH
authors.lastname: Letley
authors.forename: Greta
authors.initials: G
authors.lastname: Rait
authors.forename: David S
authors.initials: DS
authors.lastname: Tompkins
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: O'Brien
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D017250:Caliciviridae Infections / Q000175:diagnosis / Q000453:epidemiology; D002169:Campylobacter Infections / Q000175:diagnosis / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003141:Communicable Diseases / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D058006:General Practice; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007410:Intestinal Diseases / Q000453:epidemiology* / Q000382:microbiology; D007411:Intestinal Diseases, Parasitic / Q000175:diagnosis / Q000453:epidemiology; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D029322:Norovirus / Q000302:isolation & purification; D011159:Population Surveillance; D011446:Prospective Studies; D006113:United Kingdom / Q000453:epidemiology; D055815:Young Adult