[Genetic characteristic of Haemophilus influenzae type B strains isolated in Russian regions]

Genotyping of Hib strains isolated in regions of Russia as well as characterization of genetic relations of typed strains with strains isolated in other areas.Genetic characterization of 31 strains of Hib isolated in Russian regions during 2005-2008 was performed by multilocus sequence typing.Studied strains belonged to 11 variants of sequence types, 6 of which were described in previous studies, whereas other 5 were isolated for the first time during this study. The most common isolated strains were ST-92 (13 strains or 42%) and ST-6 (6 strains or 19%). Typed strains were distributed to two clonal complexes. Clonal complex "A1/A2" ("ST-6") incorporates all typed strains except ST-93 strain belonging to clonal complex "B1b" ("ST-93"). The majority of studied strains (19 or 61%) had difference from "central" sequence type of clonal complex, A1/A2 ("ST-6") on not more than one allele.Clonal structure of isolated strains is analogous to the one observed in Moscow and foreign strains.