title: Viral etiology of acute respiratory infections with cough in infancy: a community-based birth cohort study.
abstract: BACKGROUND
  Acute respiratory infections (ARI) are a major cause of morbidity in infancy worldwide, with cough and wheeze being alarming symptoms to parents. We aimed to analyze in detail the viral aetiology of ARI with such symptoms in otherwise healthy infants, including rhinoviruses and recently discovered viruses such as human metapneumovirus (HMPV), coronavirus NL63 and HKU1, and human bocavirus (HBoV).
  
  
  METHODS
  We prospectively followed 197 unselected infants during their first year of life and assessed clinical symptoms by weekly standardized interviews. At the first ARI with cough or wheeze, we analyzed nasal swabs by sensitive individual real time polymerase chain reaction assays targeting 16 different respiratory viruses.
  
  
  RESULTS
  All 112 infants who had an ARI had cough, and 39 (35%) had wheeze. One or more respiratory viruses were found in 88 of 112 (79%) cases. Fifteen (17%) dual and 3 (3%) triple infections were recorded. Rhino- (23% of all viruses) and coronaviruses (18%) were most common, followed by parainfluenza viruses (17%), respiratory syncytial virus (RSV) (16%), HMPV (13%), and HBoV (5%). Together rhinoviruses, coronaviruses, HMPV, and HBoV accounted for 60% (65 of 109) of viruses. Although symptom scores and need for general practitioner (GP) consultations were highest in infants infected with RSV, they were similar in infants infected with other viruses. Viral shedding at 3 weeks occurred in 20% of cases.
  
  
  CONCLUSIONS
  Rhinoviruses, coronaviruses, HMPV, and HBoV are common pathogens associated with respiratory symptoms in otherwise healthy infants. They should be considered in the differential diagnosis of the aetiology of ARI in this age group.
authors.affiliation: Pediatric Respiratory Medicine, University Children's Hospital of Berne, Berne, Switzerland. n.regamey@imperial.ac.uk
authors.forename: Nicolas
authors.initials: N
authors.lastname: Regamey
authors.forename: Laurent
authors.initials: L
authors.lastname: Kaiser
authors.forename: Hanna L
authors.initials: HL
authors.lastname: Roiha
authors.forename: Christelle
authors.initials: C
authors.lastname: Deffernez
authors.forename: Claudia E
authors.initials: CE
authors.lastname: Kuehni
authors.forename: Philipp
authors.initials: P
authors.lastname: Latzin
authors.forename: Christoph
authors.initials: C
authors.lastname: Aebi
authors.forename: Urs
authors.initials: U
authors.lastname: Frey
mesh_terms: D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000821:virology*; D003371:Cough / Q000821:virology*; D006801:Humans; D007231:Infant, Newborn; D011446:Prospective Studies; D012141:Respiratory Tract Infections / Q000821:virology*; D014777:Virus Diseases / Q000175:diagnosis*; D014780:Viruses / Q000145:classification / Q000302:isolation & purification