title: Features associated with severe disease in hospitalized children with 2009 influenza A (H1N1) infection at a university hospital in Riyadh, Saudi Arabia.
abstract: OBJECTIVE
  In 2009, pandemic H1N1 influenza A caused significant morbidity and mortality worldwide; however, available data on disease characteristics and outcome of hospitalized children is limited.
  
  
  METHODS
  A prospective cohort study of children who required hospitalization because of the influenza A (H1N1) infection at King Khalid University Hospital in Riyadh, Saudi Arabia, over 6 months (July- December, 2009).
  
  
  METHODS
  Data was collected using a predesigned form for all admitted pediatric cases (0-12 years) presenting with the influenza-like illness and who tested positive for the novel influenza (H1N1) using reverse transcriptase polymerase chain reaction assay. The clinical course and features associated with the severe disease among such children were described
  
  
  RESULTS
  Out of 1103 children with the influenza-like illness, 375 (34%) were confirmed pediatric cases of influenza A (H1N1), of whom 50 (13.3%) required hospitalization. The median age was 3 years (range, 1 month-12 years). Fever was the most frequent symptom (94%) at admission, followed by cough (86%) and other symptoms including vomiting and diarrhea. The majority (70%) of children had at least one underlying medical condition, with bronchial asthma being the most common (40%). All cases were treated with oseltamivir. Five children (10%) were admitted to the ICU, 4 required mechanical ventilation, and 2 died (4%).
  
  
  CONCLUSIONS
  The majority of children with 2009 H1N1 influenza A-associated hospitalization in this series had an uncomplicated course. Respiratory complications and ICU admissions were more frequent in those with underlying disease, especially asthma and neuromuscular diseases. Efforts need to be focused prior to each influenza season and special emphasis needs to be given to children by immunizing them with H1N1 influenza A vaccination to avoid severe disease and minimize complications.
authors.affiliation: Department of Pediatrics (Pulmonology Unit) College of Medicine and King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia. alsaadi@ksu.edu.sa
authors.forename: Sarah S
authors.initials: SS
authors.lastname: Al Subaie
authors.forename: Muslim A
authors.initials: MA
authors.lastname: Al Saadi
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use*; D001249:Asthma / Q000150:complications*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006760:Hospitalization; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology; D008297:Male; D053139:Oseltamivir / Q000627:therapeutic use*; D058873:Pandemics; D011446:Prospective Studies; D012307:Risk Factors; D012529:Saudi Arabia / Q000453:epidemiology
chemical_list: D000998:Antiviral Agents; D053139:Oseltamivir