title: Influenza A (H3N2) outbreak, Nepal.
abstract: In July 2004, an outbreak of influenza A (H3N2) was detected at 3 Bhutanese refugee camps in southeastern Nepal. Hemagglutination inhibition showed that approximately 40% of the viruses from this outbreak were antigenically distinct from the A/Wyoming/3/03 vaccine strain. Four amino acid differences were observed in most of the 26 isolates compared with the A/Wyoming/3/2003 vaccine strain. All 4 substitutions are located within or adjacent to known antibody-binding sites. Several isolates showed a lysine-to-asparagine substitution at position 145 (K145N) in the hemagglutinin molecule, which may be noteworthy since position 145 is located within a glycosylation site and adjacent to an antibody-binding site. H3N2 viruses continue to drift from the vaccine strain and may remain as the dominant strains during the 2005-2006 influenza season. Thus, the 2005-2006 Northern Hemisphere vaccine strain was changed to A/California/7/2004, a virus with all 4 amino acid substitutions observed in these Nepalese isolates.
authors.affiliation: Air Force Institute for Operational Health, Brooks City Base, San Antonio, Texas 78235, USA. Luke.Daum@brooks.af.mil
authors.forename: Luke T
authors.initials: LT
authors.lastname: Daum
authors.forename: Michael W
authors.initials: MW
authors.lastname: Shaw
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Klimov
authors.forename: Linda C
authors.initials: LC
authors.lastname: Canas
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Macias
authors.forename: Debra
authors.initials: D
authors.lastname: Niemeyer
authors.forename: James P
authors.initials: JP
authors.lastname: Chambers
authors.forename: Robert
authors.initials: R
authors.lastname: Renthal
authors.forename: Sanjaya K
authors.initials: SK
authors.lastname: Shrestha
authors.forename: Ramesh P
authors.initials: RP
authors.lastname: Acharya
authors.forename: Shankar P
authors.initials: SP
authors.lastname: Huzdar
authors.forename: Nirmal
authors.initials: N
authors.lastname: Rimal
authors.forename: Khin S
authors.initials: KS
authors.lastname: Myint
authors.forename: Philip
authors.initials: P
authors.lastname: Gould
mesh_terms: D000595:Amino Acid Sequence; D000940:Antigenic Variation / Q000235:genetics*; D002648:Child; D004196:Disease Outbreaks; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006388:Hemagglutinins / Q000235:genetics; D006801:Humans; D053122:Influenza A Virus, H3N2 Subtype; D009980:Influenza A virus / Q000235:genetics / Q000302:isolation & purification*; D007251:Influenza, Human / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology; D008297:Male; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009390:Nepal / Q000453:epidemiology; D010802:Phylogeny; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D006388:Hemagglutinins; D012367:RNA, Viral