title: Population structure of group B streptococcus from a low-incidence region for invasive neonatal disease.
abstract: The population structure of group B streptococcus (GBS) from a low-incidence region for invasive neonatal disease (Israel) was investigated using multilocus genotype data. The strain collection consisted of isolates from maternal carriage (n=104) and invasive neonatal disease (n=50), resolving into 46 sequence types. The most prevalent sequence types were ST-1 (17.5 %), ST-19 (10.4 %), ST-17 (9.7 %), ST-22 (8.4 %) and ST-23 (6.5 %). Serotype III was the most common, accounting for 29.2 % of the isolates. None of the serotypes was significantly associated with invasive neonatal disease. burst analysis resolved the 46 sequence types into seven lineages (clonal complexes), from which only lineage ST-17, expressing serotype III only, was significantly associated with invasive neonatal disease. Lineage ST-22 expressed mainly serotype II, and was significantly associated with carriage. The distribution of the various sequence types and lineages, and the association of lineage ST-17 with invasive disease, are consistent with the results of analyses from a global GBS isolate collection. These findings could imply that the global variation in disease incidence is independent of the circulating GBS populations, and may be more affected by other risk factors for invasive GBS disease, or by different prevention strategies.
authors.affiliation: Department of Medicine C, Ha'Emek Medical Center, Afula, Israel.
authors.forename: Naiel
authors.initials: N
authors.lastname: Bisharat
authors.affiliation: Department of Microbiology, Nuffield Department of Clinical Laboratory Sciences, John Radcliffe Hospital, University of Oxford, Oxford, UK.
authors.forename: Nicola
authors.initials: N
authors.lastname: Jones
authors.affiliation: Departments of Bacteriology and Infectious Diseases, Soroka Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Dror
authors.initials: D
authors.lastname: Marchaim
authors.affiliation: Clinical Microbiology Unit, Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Hospital, Jerusalem, Israel.
authors.forename: Colin
authors.initials: C
authors.lastname: Block
authors.affiliation: The Oxford Centre for Gene Function, University of Oxford, Oxford, UK.
authors.forename: Rosalind M
authors.initials: RM
authors.lastname: Harding
authors.affiliation: Departments of Bacteriology and Infectious Diseases, Soroka Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Pablo
authors.initials: P
authors.lastname: Yagupsky
authors.affiliation: The Academic Department of Microbiology and Infectious Disease, John Radcliffe Hospital, University of Oxford, Oxford, UK.
authors.forename: Tim
authors.initials: T
authors.lastname: Peto
authors.affiliation: Department of Microbiology, Nuffield Department of Clinical Laboratory Sciences, John Radcliffe Hospital, University of Oxford, Oxford, UK.
authors.forename: Derrick W
authors.initials: DW
authors.lastname: Crook
mesh_terms: D002353:Carrier State / Q000453:epidemiology / Q000382:microbiology; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005260:Female; D005838:Genotype; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007557:Israel / Q000453:epidemiology; D017720:Molecular Epidemiology; D017422:Sequence Analysis, DNA; D012703:Serotyping; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D013292:Streptococcus agalactiae / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D004269:DNA, Bacterial