title: Human Coronavirus in the 2014 Winter Season as a Cause of Lower Respiratory Tract Infection.
abstract: OBJECTIVE
  During the late autumn to winter season (October to December) in the Republic of Korea, respiratory syncytial virus (RSV) is the most common pathogen causing lower respiratory tract infections (LRTIs). Interestingly, in 2014, human coronavirus (HCoV) caused not only upper respiratory infections but also LRTIs more commonly than in other years. Therefore, we sought to determine the epidemiology, clinical characteristics, outcomes, and severity of illnesses associated with HCoV infections at a single center in Korea.
  
  
  METHODS
  We retrospectively identified patients with positive HCoV respiratory specimens between October 2014 and December 2014 who were admitted to Severance Children's Hospital at Yonsei University Medical Center for LRTI. Charts of the patients with HCoV infection were reviewed and compared with RSV infection.
  
  
  RESULTS
  During the study period, HCoV was the third most common respiratory virus and accounted for 13.7% of infections. Coinfection was detected in 43.8% of children with HCoV. Interestingly, one patient had both HCoV-OC43 and HCoV-NL63. Mild pneumonia was most common (60.4%) with HCoV, and when combined with RSV, resulted in bronchiolitis. Two patients required care in the intensive care unit. However, compared with that of RSV infection, the disease course HCoV was short.
  
  
  CONCLUSIONS
  Infections caused by HCoVs are common, and can cause LRTIs. During an epidemic season, clinicians should be given special consideration thereto. When combined with other medical conditions, such as neurologic or cardiologic diseases, intensive care unit (ICU) care may be necessary.
authors.affiliation: Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kyu Yeun
authors.initials: KY
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Song Yi
authors.initials: SY
authors.lastname: Han
authors.affiliation: Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Ho Seong
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Division of Respiratory Viruses, Center for Infectious Diseases, Korea National Institute of Health, Korea Center for Disease Control and Prevention, Cheongju, Korea.
authors.forename: Hyang Min
authors.initials: HM
authors.lastname: Cheong
authors.affiliation: Division of Respiratory Viruses, Center for Infectious Diseases, Korea National Institute of Health, Korea Center for Disease Control and Prevention, Cheongju, Korea.
authors.forename: Sung Soon
authors.initials: SS
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea. DSKIM6634@yuhs.ac.
authors.forename: Dong Soo
authors.initials: DS
authors.lastname: Kim
mesh_terms: D002648:Child; D002675:Child, Preschool; D017934:Coronavirus / Q000302:isolation & purification*; D018352:Coronavirus Infections / Q000453:epidemiology / Q000821:virology*; D028962:Coronavirus OC43, Human / Q000302:isolation & purification; D005260:Female; D006760:Hospitalization; D006801:Humans; D007223:Infant; D008297:Male; D056910:Republic of Korea / Q000453:epidemiology; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000821:virology*; D012189:Retrospective Studies; D012621:Seasons
keywords: Coronavirus; children; clinical severity; respiratory syncytial virus; respiratory viruses