title: The effect of exclusive breast-feeding on respiratory illness in young infants in a maternal immunization trial in Bangladesh.
abstract: BACKGROUND
  Exclusive breast-feeding reduces the risk of respiratory illness in infants younger than 6 months of age in developing countries by approximately half. We evaluated the effect of exclusive breast-feeding on respiratory illness with fever (RIF) in Bangladeshi infants in the context of a randomized maternal influenza immunization trial.
  
  
  METHODS
  Infants in a maternal vaccine trial in Dhaka, Bangladesh, were prospectively assessed at weekly intervals for 6 months after birth for breast-feeding practices and RIF. We estimated the risk of an RIF episode for infants who were exclusively breast-fed the prior week compared with infants not exclusively breast-fed the prior week using generalized estimating equations.
  
  
  RESULTS
  We followed a total of 331 infants from birth to 24 weeks of age. The median weeks infants were exclusively breast-fed was 15 (interquartile range, 6-21). The adjusted independent odds of respiratory illness for exclusively breast-fed infants compared with nonexclusively breast-fed infants was 0.59 (95% confidence interval: 0.45-0.77) for an RIF episode. After adjusting for exclusive breast-feeding, we confirmed the previous report that maternal immunization with influenza vaccine had an independent protective effect against RIF (odds ratio, 0.72; 95% confidence interval: 0.55-0.93). No significant difference in the protective effect of exclusive breast-feeding was seen by maternal influenza immunization status.
  
  
  CONCLUSIONS
  Exclusive breast-feeding during the first 6 months of life and maternal immunization with influenza vaccine independently and substantially reduced respiratory illness with fever in infants.
authors.affiliation: Center for Health Research-Northwest, Kaiser Permanente, Portland, OR, USA. emhenkle@gmail.com
authors.forename: Emily
authors.initials: E
authors.lastname: Henkle
authors.forename: Mark C
authors.initials: MC
authors.lastname: Steinhoff
authors.forename: Saad B
authors.initials: SB
authors.lastname: Omer
authors.forename: Eliza
authors.initials: E
authors.lastname: Roy
authors.forename: Shams E
authors.initials: SE
authors.lastname: Arifeen
authors.forename: Rubhana
authors.initials: R
authors.lastname: Raqib
authors.forename: Robert F
authors.initials: RF
authors.lastname: Breiman
authors.forename: Laura E
authors.initials: LE
authors.lastname: Caulfield
authors.forename: William J
authors.initials: WJ
authors.lastname: Moss
authors.forename: Khalequ
authors.initials: K
authors.lastname: Zaman
mesh_terms: D000328:Adult; D001459:Bangladesh / Q000453:epidemiology; D001942:Breast Feeding / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007114:Immunization / Q000706:statistics & numerical data*; D007223:Infant; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000453:epidemiology* / Q000517:prevention & control; D008297:Male; D016017:Odds Ratio; D011446:Prospective Studies; D012140:Respiratory Tract Diseases / Q000453:epidemiology* / Q000517:prevention & control; D012307:Risk Factors