title: Natural genetic transfer of a putative virulence-enhancing mutation to Haemophilus influenzae type a.
abstract: Haemophilus influenzae strains of serotype a very rarely cause life-threatening infections. Examination of strains from the Gambia, West Africa, that caused septicemia, meningitis, or both revealed that a clone has emerged that carries a DNA deletion previously identified only in type b strains that is hypothesized to contribute to the special virulence of that serotype. This clone appears to have arisen by transfer of DNA between type a and type b strains, a transformation event that has happened more than once, as shown by the discovery Kenya, East Africa, of a clonally distinct type a strain bearing the identical deletion. The implications for the emergence of clinically important non-type b strains of H. influenzae are obvious.
authors.affiliation: Department of Paediatrics, Oxford University, John Radcliffe Hospital, United Kingdom.
authors.forename: J S
authors.initials: JS
authors.lastname: Kroll
authors.forename: E R
authors.initials: ER
authors.lastname: Moxon
authors.forename: B M
authors.initials: BM
authors.lastname: Loynds
mesh_terms: D000595:Amino Acid Sequence; D016470:Bacteremia / Q000382:microbiology; D001483:Base Sequence; D004247:DNA; D005714:Gambia; D018014:Gene Transfer Techniques; D006801:Humans; D009980:Influenza A virus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D008583:Meningitis, Haemophilus / Q000382:microbiology; D008969:Molecular Sequence Data; D009154:Mutation; D012703:Serotyping; D014774:Virulence / Q000235:genetics
chemical_list: D004247:DNA