title: Epidemiology of 2009 pandemic influenza A virus subtype H1N1 among Kenyans aged 2 months to 18 years, 2009-2010.
abstract: BACKGROUND
  The US Army Medical Research Unit-Kenya (USAMRU-K) conducts surveillance for influenza-like illness (ILI) in Kenya. We describe the temporal and geographic progression of A(H1N1)pdm09 as it emerged in Kenya and characterize the outpatient population with A(H1N1)pdm09 infection.
  
  
  METHODS
  We included patients with ILI aged 2 months to 18 years enrolled during June 2009-August 2010. Respiratory specimens were tested by real-time reverse-transcription polymerase chain reaction for influenza virus. Patients with A(H1N1)pdm09 infection were compared to those with seasonal influenza A virus infection and those with ILI who had no virus or a virus other than influenza virus identified (hereafter, "noninfluenza ILI").
  
  
  RESULTS
  Of 4251 patients with ILI, 193 had laboratory-confirmed A(H1N1)pdm09 infection. The first pandemic influenza case detected by USAMRU-K surveillance was in August 2009; peak activity nationwide occurred during October-November 2009. Patients with A(H1N1)pdm09 infection were more likely to be school-aged, compared with patients with seasonal influenza A virus infection (prevalence ratio [PR], 2.0; 95% confidence interval [CI], 1.3-3.1) or noninfluenza ILI (PR, 3.2; 95% CI, 2.4-4.3).
  
  
  CONCLUSIONS
  USAMRU-K ILI surveillance detected the geographic and temporal distribution of pandemic influenza in Kenya. The age distribution of A(H1N1)pdm09 infections included more school-aged children, compared with seasonal influenza A virus infection and noninfluenza ILI.
authors.affiliation: Department of Medicine, University of California–San Francisco, USA.
authors.forename: Karen K
authors.initials: KK
authors.lastname: Wong
authors.forename: Wallace D
authors.initials: WD
authors.lastname: Bulimo
authors.forename: Japhet
authors.initials: J
authors.lastname: Magana
authors.forename: Rachel A
authors.initials: RA
authors.lastname: Achilla
authors.forename: Sandra K
authors.initials: SK
authors.lastname: Schwarcz
authors.forename: Maylor
authors.initials: M
authors.lastname: Simwa
authors.forename: Janet M
authors.initials: JM
authors.lastname: Majanja
authors.forename: Meshack O
authors.initials: MO
authors.lastname: Wadegu
authors.forename: Finley A
authors.initials: FA
authors.lastname: Osuna
authors.forename: Silvanos O
authors.initials: SO
authors.lastname: Mukunzi
authors.forename: Josephat K
authors.initials: JK
authors.lastname: Mwangi
authors.forename: Julia M
authors.initials: JM
authors.lastname: Wangui
authors.forename: Janet N
authors.initials: JN
authors.lastname: Muthoni
authors.forename: James O
authors.initials: JO
authors.lastname: Njiri
authors.forename: Beryl D
authors.initials: BD
authors.lastname: Obura
authors.forename: Benjamin H
authors.initials: BH
authors.lastname: Opot
authors.forename: Keneth K
authors.initials: KK
authors.lastname: Mitei
authors.forename: Jane
authors.initials: J
authors.lastname: Barani
authors.forename: Samwel
authors.initials: S
authors.lastname: Lifumo
authors.forename: David C
authors.initials: DC
authors.lastname: Schnabel
mesh_terms: D000293:Adolescent; D017677:Age Distribution; D012634:Bodily Secretions / Q000821:virology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification*; D007251:Influenza, Human / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D007630:Kenya / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D012137:Respiratory System / Q000821:virology; D013997:Time Factors; D019371:Topography, Medical