title: Human metapnuemovirus infections in hospitalized children and comparison with other respiratory viruses. 2005-2014 prospective study.
abstract: BACKGROUND
  Human metapneumovirus (HMPV) has an important etiological role in acute lower respiratory infections in children under five years. Our objectives were to estimate the relative contribution of HMPV to hospitalization in children with acute respiratory infection, to define the clinical and epidemiological features of HMPV single and multiple infections, and to compare HMPV infections with respiratory syncytial virus (HRSV), rhinovirus (HRV), adenovirus and human bocavirus infections in the same population.
  
  
  RESULTS
  A prospective study performed on all children less than 14 years of age with a respiratory tract disease admitted to a secondary hospital between September 2005- June 2014. Clinical characteristics of patients were analyzed. Nasopharyngeal aspirate was taken at admission for viral study with polymerase chain reaction for 16 respiratory viruses. A total of 3,906 children were included. At least one respiratory virus was detected in 75.2% of them. The most common identified virus was HRSV, followed by HRV. HMPV was detected in 214 cases (5.5%); 133 (62%) were single infections and the remaining were detected in coinfection with other viruses. 90.7% cases were detected between February and May. Children's mean age was 13.83 ± 18 months. Fever was frequent (69%), and bronchiolitis (27%), and recurrent wheezing (63%) were the main clinical diagnosis. Hypoxia was present in 65% of the patients and 47% of them had an infiltrate in X-ray. Only 6 (2.8%) children were admitted to the intensive care unit. Only the duration of the hospitalization was different, being longer in the coinfections group (p <0.05). There were many differences in seasonality and clinical characteristics between HMPV and other respiratory viruses being more similar to HRSV.
  
  
  CONCLUSIONS
  HMPV infections accounted for 5.5% of total viral infections in hospitalized children. The clinical characteristics were similar to HRSV infections, but seasonality and clinical data were different from other viral infections.
authors.affiliation: Pediatrics Department, Severo Ochoa Hospital, Leganés, Madrid, Spain.|University Alfonso X el Sabio, Madrid, Spain.|Traslational Research Network in Pediatric Infectious Diseases (RITIP), Madrid, Spain.
authors.forename: María Luz
authors.initials: ML
authors.lastname: García-García
authors.affiliation: Pediatrics Department, Severo Ochoa Hospital, Leganés, Madrid, Spain.|University Alfonso X el Sabio, Madrid, Spain.|Traslational Research Network in Pediatric Infectious Diseases (RITIP), Madrid, Spain.|TEDDY Network Member (European Network of Excellence for Pediatric Clinical Research, Bari, Italy).
authors.forename: Cristina
authors.identifier: http://orcid.org/0000-0002-6503-3423
authors.initials: C
authors.lastname: Calvo
authors.affiliation: University Alfonso X el Sabio, Madrid, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Rey
authors.affiliation: University Alfonso X el Sabio, Madrid, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Díaz
authors.affiliation: Respiratory Viruses and Influenza Unit, National Microbiology Center (ISCIII), Madrid, Spain.
authors.forename: Maria Del Mar
authors.initials: MD
authors.lastname: Molinero
authors.affiliation: Traslational Research Network in Pediatric Infectious Diseases (RITIP), Madrid, Spain.|Respiratory Viruses and Influenza Unit, National Microbiology Center (ISCIII), Madrid, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Pozo
authors.affiliation: Traslational Research Network in Pediatric Infectious Diseases (RITIP), Madrid, Spain.|Respiratory Viruses and Influenza Unit, National Microbiology Center (ISCIII), Madrid, Spain.
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Casas
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006760:Hospitalization; D006801:Humans; D007223:Infant; D008297:Male; D029121:Metapneumovirus / Q000302:isolation & purification*; D011446:Prospective Studies; D012141:Respiratory Tract Infections / Q000821:virology*; D013030:Spain