title: Recorded infections and antibiotics in early life: associations with allergy in UK children and their parents.
abstract: BACKGROUND
  It is suggested that the inverse relationship between allergic disease and family size reflects reduced exposure to early life infections, and that antibiotic treatment in childhood diminishes any protective effect of such infection.
  
  
  METHODS
  A birth cohort study was undertaken in 642 children recruited before birth and seen annually until the age of 8 years. Reported infections and prescribed antibiotics by the age of 5 years were counted from GP records and comparisons were made with a previous study of their parents.
  
  
  RESULTS
  At the age of 8 years, 104 children (19%) were atopic, 79 (13%) were currently wheezy and 124 (21%) had seasonal rhinitis. 577 children (97%) had at least three infections recorded by age 5, a figure much higher than that of their parents (69%). By the age of 5 only 11 children (2%) had never received a prescription for antibiotics; the corresponding figure for the parents was 24%. Higher numbers of infections were recorded for firstborn children. After adjusting for parental atopy and birth order, there was no association between infection counts and atopy (OR 1.01 (95% CI 0.99 to 1.03) per infection). Significant positive associations were found for wheeze and seasonal rhinitis. An increased risk of current wheeze was found for each antibiotic prescription (adjusted OR 1.07 (95% CI 1.03 to 1.10)) but not for atopy. This was primarily explained by prescriptions for respiratory infections. Similar patterns were observed for seasonal rhinitis.
  
  
  CONCLUSIONS
  Despite very high rates of recorded early life infections and antibiotic prescriptions, no plausibly causative relationships were found with subsequent respiratory allergies.
authors.affiliation: Occupational and Environmental Medicine, Imperial College School of Medicine (NHLI), Manresa Road, London SW3 6LR, UK. jessica.harris@imperial.ac.uk
authors.forename: Jessica M
authors.initials: JM
authors.lastname: Harris
authors.forename: Pamela
authors.initials: P
authors.lastname: Mills
authors.forename: Carol
authors.initials: C
authors.lastname: White
authors.forename: Susan
authors.initials: S
authors.lastname: Moffat
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Newman Taylor
authors.forename: Paul
authors.initials: P
authors.lastname: Cullinan
mesh_terms: D000328:Adult; D017677:Age Distribution; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D005192:Family Health; D005260:Female; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000453:epidemiology* / Q000235:genetics; D007223:Infant; D007231:Infant, Newborn; D007239:Infections / Q000453:epidemiology*; D008297:Male; D010290:Parents; D010375:Pedigree; D006113:United Kingdom / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents