title: Comparison of the etiology of viral respiratory illnesses in inner-city and suburban infants.
abstract: BACKGROUND
  The risk of developing childhood asthma has been linked to the severity and etiology of viral respiratory illnesses in early childhood. Since inner-city infants have unique environmental exposures, we hypothesized that patterns of respiratory viral infections would also be distinct.
  
  
  METHODS
  We compared the viral etiology of respiratory illnesses in 2 groups: a cohort of 515 infants from 4 inner-city areas and a cohort of 285 infants from mainly suburban Madison, Wisconsin. Nasal secretions were sampled during periods of respiratory illness and at 1 year of age and were analyzed for viral pathogens by multiplex polymerase chain reaction.
  
  
  RESULTS
  Overall, inner-city infants had lower rates of viral detection. Considering specific viruses, sick urban infants had lower rates of detectable rhinovirus or respiratory syncytial virus infection and higher rates of adenovirus infection. Every urban site had a higher proportion of adenovirus-positive samples associated with illnesses (10%-21%), compared with Madison (6%).
  
  
  CONCLUSIONS
  These findings provide evidence that inner-city babies have different patterns of viral respiratory illnesses than babies who grow up in a more suburban location. These findings raise important questions about the etiology of virus-negative illnesses in urban infants and the possibility of long-term consequences of early life infections with adenovirus in this population.
authors.affiliation: Department of Pediatrics, University of Wisconsin, Madison, WI, USA. gern@medicine.wisc.edu
authors.forename: James E
authors.initials: JE
authors.lastname: Gern
authors.forename: Tressa
authors.initials: T
authors.lastname: Pappas
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Visness
authors.forename: Katy F
authors.initials: KF
authors.lastname: Jaffee
authors.forename: Robert F
authors.initials: RF
authors.lastname: Lemanske
authors.forename: Alkis
authors.initials: A
authors.lastname: Togias
authors.forename: Gordon R
authors.initials: GR
authors.lastname: Bloomberg
authors.forename: William W
authors.initials: WW
authors.lastname: Cruikshank
authors.forename: Carin
authors.initials: C
authors.lastname: Lamm
authors.forename: Marina
authors.initials: M
authors.lastname: Tuzova
authors.forename: Robert A
authors.initials: RA
authors.lastname: Wood
authors.forename: Wai Ming
authors.initials: WM
authors.lastname: Lee
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005122:Exudates and Transudates / Q000821:virology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D060885:Multiplex Polymerase Chain Reaction; D009666:Nose / Q000821:virology; D012141:Respiratory Tract Infections / Q000453:epidemiology* / Q000821:virology*; D013383:Suburban Population; D014505:Urban Population; D014777:Virus Diseases / Q000453:epidemiology* / Q000821:virology*; D014780:Viruses / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D014922:Wisconsin / Q000453:epidemiology