title: Associated factors for diagnosis of influenza A (H1N1) 2009 in patients presenting to Rajavithi Hospital.
abstract: BACKGROUND
  The pandemic influenza A (H1N1) 2009 was a global outbreak of a new strain of influenza A virus. The associated factors of influenza A (H1N1) 2009 infection in Thailand have not been well studied.
  
  
  OBJECTIVE
  To determine the associated factors for diagnosis of influenza A (H1N1) 2009.
  
  
  METHODS
  Retrospective analytical study
  
  
  METHODS
  A total 430 patients who had influenza-like symptoms from the out-patient department of Rajavithi Hospital in Thailand were analyzed by collecting the hospital charts of the patients between 1 June 2009 and 31 August 2009, total 3 months. The patients' personal information, signs and symptoms, laboratory data and throat swab for influenza A (H1N1) 2009 virus confirmed by real time reverse transcription polymerase chain reaction were analyzed.
  
  
  RESULTS
  There were 152 (35.3%) influenza A (H1N1) 2009 confirmed-case patients, 100 (65.80%) were female and 52 (34.2%) were male. The average age was 28.2 +/- 15.6 years and the most occupation were housewives (56.6%) and students (36.8%). The patients presented with acute fever (100.00%), cough (95.4%), rhinorrhea (66.4%), dyspnea (27.0%) and the mean duration of fever was 4.3 +/- 2.9 days at the time of sample collection. Laboratory finding such as leukocytes count, platelets count, lactate dehydrogenase and chest x-ray were normal in most cases. The associated factors of influenza A (H1N1) 2009 infection were age < 35, pregnancy, rhinorrhea and white blood count < 10,000 cells/ml3.
  
  
  CONCLUSIONS
  The associated factors of influenza A (H1N1) 2009 were age < 35 years, pregnancy rhinorrhea and white blood count < 10,000 cells/ml3.
authors.affiliation: Department ofMedicine, Rajavithi Hospital, College of Medicine, Rangsit University, Bangkok, Thailand. Somkidou@yahoo.com
authors.forename: Somkid
authors.initials: S
authors.lastname: Unsematham
authors.forename: Wiporn
authors.initials: W
authors.lastname: Ketbumrongporn
authors.forename: Kanya
authors.initials: K
authors.lastname: Boonthongtho
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000175:diagnosis*; D007958:Leukocyte Count; D008297:Male; D015999:Multivariate Analysis; D011247:Pregnancy; D012189:Retrospective Studies; D013785:Thailand