title: Molecular characterisation of group A Neisseria meningitidis isolated in Sudan 1985-2001.
abstract: A total of 33 group A Neisseria meningitidis (Mc) isolates, collected in Sudan between 1985 and 2001, were studied in order to describe the changes over time in a country within the meningitis belt of Africa. The isolates were characterised by traditional phenotypic methods (serogrouping, serotyping, serosubtyping and antibiogram) and molecular techniques (genosubtyping, pulsed-field gel electrophoresis [PFGE] with restriction endonucleases SpeI and NheI, and multilocus sequence typing [MLST]). Three clones of group A Mc were identified: one before 1988 (sulphadiazine sensitive, serotype 4, genosubtype P1.7,13-1,35-1, sequence type 4 [ST-4]); another during and after the 1988 epidemic (sulphadiazine resistant, serotype 4, genosubtype P1.20,9,35-1, ST-5); and a third causing the 1999 epidemic (sulphadiazine resistant, serotype 4, genosubtype P1.20,9,35-1, ST-7). The first clone showed major differences compared to the other two. The second and third clones had many similarities with differences in only a single gene (pgm) in the MLST (47 of the 450 bp) but significant other differences according to the PFGE patterns. Within the clones, genosubtyping and MLST gave identical information (except one base substitution in the aroE gene in one isolate). However, the PFGE patterns showed changes over time within the clones, where SpeI revealed somewhat more diversity than NheI.
authors: National Reference Laboratory for Pathogenic Neisseria, Department of Clinical Microbiology, Orebro University Hospital, Orebro, Sweden. susanne.jacobsson@orebroll.se
authors: Susanne
authors: S
authors: Jacobsson
authors: Mohamed
authors: M
authors: Issa
authors: Magnus
authors: M
authors: Unemo
authors: Anders
authors: A
authors: Bäckman
authors: Paula
authors: P
authors: Mölling
authors: Nageeb
authors: N
authors: Sulaiman
authors: Per
authors: P
authors: Olcén
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005838:Genotype; D006801:Humans; D008585:Meningitis, Meningococcal / Q000453:epidemiology / Q000382:microbiology*; D017720:Molecular Epidemiology; D009345:Neisseria meningitidis / Q000145:classification / Q000187:drug effects / Q000235:genetics*; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA; D012703:Serotyping; D013397:Sudan / Q000453:epidemiology; D013411:Sulfadiazine / Q000494:pharmacology
chemical_list: D000890:Anti-Infective Agents; D004269:DNA, Bacterial; D013411:Sulfadiazine