title: [Infant pneumonia at periodic check-ups. Characteristics and associated factors].
abstract: BACKGROUND
  Each year, pneumonia is the cause of death of forty thousand children under four years of age in America.
  
  
  OBJECTIVE
  To follow children from birth until two years of age and record episodes of pneumonia, their features and associated factors.
  
  
  METHODS
  Four hundred thirty seven healthy newborns were followed in a public out patient clinic of Northern Santiago until two years of age. Pneumonia was diagnosed using clinical or radiological criteria. The mothers of each child were interviewed in each follow up visit.
  
  
  RESULTS
  Two hundred ten episodes of pneumonia were detected during the study, 0.6 episodes per child and 1.8 episodes per affected child. Sixty six percent of episodes occurred during the first year of age. Total prevalence was 22.4 and 14.3% during the first and second year of age respectively. Semi annual incidence was 13.8 and 5.5% during the first and fourth semester respectively. Children that had pneumonia, were male in a higher proportion, had a lower birth weight, had higher number of brothers, mothers with less that 8 years of school courses and a lower socioeconomic level. During the first year of life, breast feeding during less than four months and a birth date during spring and summer were associated with a higher incidence of pneumonia. Seventy seven episodes, that occurred in 48 children, required hospitalization. The hospitalization rate for the whole cohort was 13.4% percent and 41.2% for affected children. Mean hospital stay was 5.8 days. Risk factors for hospitalization were male sex, less than four months of breast feeding, low birth weight, to have brothers, a lower mother education and lower socioeconomic level. Two children died.
  
  
  CONCLUSIONS
  One out of three healthy newborns had pneumonia during the first year of life and a low socioeconomic level was an important risk factor.
authors.affiliation: Escuela de Salud Pública, Facultad de Medicina, Universidad de Chile. Santiago de Chile.
authors.forename: I
authors.initials: I
authors.lastname: López
authors.forename: H
authors.initials: H
authors.lastname: Sepúlveda
authors.forename: I
authors.initials: I
authors.lastname: Valdés
mesh_terms: D017050:Episode of Care; D005260:Female; D006760:Hospitalization; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011014:Pneumonia / Q000453:epidemiology*; D011446:Prospective Studies