title: Clinical disease in children associated with newly described coronavirus subtypes.
abstract: OBJECTIVE
  Coronaviruses cause upper respiratory illness and occasionally lower tract disease in susceptible populations. In this study we examined the prevalence of 4 human coronaviruses, including subtypes OC43, 229E, and the recently described NL63 and HKU1 in a pediatric population presenting to a children's hospital.
  
  
  METHODS
  Specimens collected over a 1-year period from pediatric patients presenting with acute respiratory illness were analyzed for the presence of 4 coronavirus subtypes using consensus and subtype-specific real-time reverse-transcription polymerase chain reaction assays. The demographic and clinical characteristics associated with coronavirus infection were examined retrospectively.
  
  
  RESULTS
  Coronaviruses were detected in 66 of 1043 children. Eight, 11, 19, and 28 specimens were positive for subtypes 229E, NL63, OC43, and HKU1, respectively. Coronaviruses were detected throughout the study period; all 4 of the subtypes were present simultaneously in December. The acute clinical features were similar across subtypes. Of 32 children infected with a coronavirus as the sole respiratory pathogen, 13 had lower respiratory tract disease. Children whose only detectable respiratory virus was a coronavirus were more likely to have underlying chronic disease than were children coinfected with another respiratory virus.
  
  
  CONCLUSIONS
  Although 4 subtypes of coronavirus were detected, the recently discovered coronavirus subtypes NL63 and HKU1 accounted for the majority of coronaviruses detected in our cohort of mostly hospitalized children with respiratory symptoms. New subtypes likely represent a substantial portion of previously unexplained respiratory illnesses.
authors.affiliation: Department of Laboratory Medicine, University of Washington, Seattle, Washington, USA. jane.kuypers@seattlechildrens.org
authors.forename: Jane
authors.initials: J
authors.lastname: Kuypers
authors.forename: Emily T
authors.initials: ET
authors.lastname: Martin
authors.forename: Judson
authors.initials: J
authors.lastname: Heugel
authors.forename: Nancy
authors.initials: N
authors.lastname: Wright
authors.forename: Rhoda
authors.initials: R
authors.lastname: Morrow
authors.forename: Janet A
authors.initials: JA
authors.lastname: Englund
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D017934:Coronavirus / Q000145:classification* / Q000302:isolation & purification; D018352:Coronavirus Infections / Q000821:virology*; D005260:Female; D006801:Humans; D016867:Immunocompromised Host; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012141:Respiratory Tract Infections / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction