title: Timing of routine infant vaccinations and risk of food allergy and eczema at one year of age.
abstract: BACKGROUND
  Epidemiological evidence suggests that routine vaccinations can have nontargeted effects on susceptibility to infections and allergic disease. Such effects may depend on age at vaccination, and a delay in pertussis vaccination has been linked to reduced risk of allergic disease. We aimed to test the hypothesis that delay in vaccines containing diphtheria-tetanus-acellular pertussis (DTaP) is associated with reduced risk of food allergy and other allergic diseases.
  
  
  METHODS
  HealthNuts is a population-based cohort in Melbourne, Australia. Twelve-month-old infants were skin prick-tested to common food allergens, and sensitized infants were offered oral food challenges to determine food allergy status. In this data linkage study, vaccination data for children in the HealthNuts cohort were obtained from the Australian Childhood Immunisation Register. Associations were examined between age at the first dose of DTaP and allergic disease.
  
  
  RESULTS
  Of 4433 children, 109 (2.5%) received the first dose of DTaP one month late (delayed DTaP). Overall, delayed DTaP was not associated with primary outcomes of food allergy (adjusted odds ratio (aOR) 0.77; 95% CI: 0.36-1.62, P = 0.49) or atopic sensitization (aOR: 0.66; 95% CI: 0.35-1.24, P = 0.19). Amongst secondary outcomes, delayed DTaP was associated with reduced eczema (aOR: 0.57; 95% CI: 0.34-0.97, P = 0.04) and reduced use of eczema medication (aOR: 0.45; 95% CI: 0.24-0.83, P = 0.01).
  
  
  CONCLUSIONS
  There was no overall association between delayed DTaP and food allergy; however, children with delayed DTaP had less eczema and less use of eczema medication. Timing of routine infant immunizations may affect susceptibility to allergic disease.
authors.affiliation: Gastro & Food Allergy, Murdoch Childrens Research Institute, Parkville, VIC, Australia.|Department of General Medicine, The Royal Children's Hospital, Parkville, VIC, Australia.
authors.forename: N
authors.initials: N
authors.lastname: Kiraly
authors.affiliation: Gastro & Food Allergy, Murdoch Childrens Research Institute, Parkville, VIC, Australia.|Melbourne School of Population and Global Health, The University of Melbourne, Carlton, VIC, Australia.
authors.forename: J J
authors.initials: JJ
authors.lastname: Koplin
authors.affiliation: Department of General Medicine, The Royal Children's Hospital, Parkville, VIC, Australia.|SAEFVIC, Murdoch Childrens Research Institute, Parkville, VIC, Australia.|Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia.
authors.forename: N W
authors.initials: NW
authors.lastname: Crawford
authors.affiliation: Department of General Medicine, The Royal Children's Hospital, Parkville, VIC, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Bannister
authors.affiliation: Department of Immunology, Monash University, Prahran, VIC, Australia.
authors.forename: K L
authors.initials: KL
authors.lastname: Flanagan
authors.affiliation: Telethon Institute for Child Health Research, University of Western Australia, Perth, WA, Australia.|Queensland Children's Medical Research Institute, University of Queensland, Brisbane, QLD, Australia.
authors.forename: P G
authors.initials: PG
authors.lastname: Holt
authors.affiliation: Gastro & Food Allergy, Murdoch Childrens Research Institute, Parkville, VIC, Australia.|Melbourne School of Population and Global Health, The University of Melbourne, Carlton, VIC, Australia.
authors.forename: L C
authors.initials: LC
authors.lastname: Gurrin
authors.affiliation: Gastro & Food Allergy, Murdoch Childrens Research Institute, Parkville, VIC, Australia.|Melbourne School of Population and Global Health, The University of Melbourne, Carlton, VIC, Australia.
authors.forename: A J
authors.identifier: http://orcid.org/0000-0002-4691-8162
authors.initials: AJ
authors.lastname: Lowe
authors.affiliation: Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia.|Allergy & Immune Disorders, Murdoch Childrens Research Institute, Manchester, UK.|Department of Allergy and Immunology, The Royal Children's Hospital, Manchester, UK.
authors.forename: M L K
authors.initials: ML
authors.lastname: Tang
authors.affiliation: Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia.|Community Health Services Research, Murdoch Childrens Research Institute, Manchester, UK.|The Centre for Community Child Health, The Royal Children's Hospital, Manchester, UK.
authors.forename: M
authors.initials: M
authors.lastname: Wake
authors.affiliation: Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia.|Environmental & Genetic Epidemiology Research, Murdoch Childrens Research Institute, Manchester, UK.
authors.forename: A-L
authors.initials: AL
authors.lastname: Ponsonby
authors.affiliation: Gastro & Food Allergy, Murdoch Childrens Research Institute, Parkville, VIC, Australia.|Melbourne School of Population and Global Health, The University of Melbourne, Carlton, VIC, Australia.
authors.forename: S C
authors.initials: SC
authors.lastname: Dharmage
authors.affiliation: Gastro & Food Allergy, Murdoch Childrens Research Institute, Parkville, VIC, Australia.|Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia.|Department of Allergy and Immunology, The Royal Children's Hospital, Manchester, UK.|Institute of Inflammation and Repair, University of Manchester, Manchester, UK.
authors.forename: K J
authors.initials: KJ
authors.lastname: Allen
mesh_terms: D015331:Cohort Studies; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage / Q000009:adverse effects; D004333:Drug Administration Routes; D004485:Eczema / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D005512:Food Hypersensitivity / Q000453:epidemiology* / Q000209:etiology*; D006801:Humans; D007223:Infant; D008297:Male; D016017:Odds Ratio; D017063:Outcome Assessment, Health Care; D011159:Population Surveillance; D012306:Risk; D013997:Time Factors; D014611:Vaccination / Q000009:adverse effects* / Q000379:methods*; D014612:Vaccines / Q000008:administration & dosage / Q000009:adverse effects
chemical_list: D015721:Diphtheria-Tetanus-Pertussis Vaccine; D014612:Vaccines
keywords: Atopic hypersensitivity; DTaP vaccine; eczema; food allergy; infant