Multispacer sequence typing relapsing fever Borreliae in Africa.
BACKGROUND
In Africa, relapsing fevers are neglected arthropod-borne infections caused by closely related Borrelia species. They cause mild to deadly undifferentiated fever particularly severe in pregnant women. Lack of a tool to genotype these Borrelia organisms limits knowledge regarding their reservoirs and their epidemiology.


RESULTS
Genome sequence analysis of Borrelia crocidurae, Borrelia duttonii and Borrelia recurrentis yielded 5 intergenic spacers scattered between 10 chromosomal genes that were incorporated into a multispacer sequence typing (MST) approach. Sequencing these spacers directly from human blood specimens previously found to be infected by B. recurrentis (30 specimens), B. duttonii (17 specimens) and B. crocidurae (13 specimens) resolved these 60 strains and the 3 type strains into 13 species-specific spacer types in the presence of negative controls. B. crocidurae comprised of 8 spacer types, B. duttonii of 3 spacer types and B. recurrentis of 2 spacer types.


CONCLUSIONS
Phylogenetic analyses of MST data suggested that B. duttonii, B. crocidurae and B. recurrentis are variants of a unique ancestral Borrelia species. MST proved to be a suitable approach for identifying and genotyping relapsing fever borreliae in Africa. It could be applied to both vectors and clinical specimens.
Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), UMR CNRS 6236 IRD 198, Faculté de Médecine, Méditerranée Infection, Aix-Marseille Université, Marseille, France.
Haitham
H
Elbir
Elbir
E
Haitham
Gregory
G
Gimenez
Cheikh
C
Sokhna
Kassahun Desalegn
KD
Bilcha
Jemal
J
Ali
Stephen C
SC
Barker
Sally J
SJ
Cutler
Didier
D
Raoult
Michel
M
Drancourt
D000349:Africa; D001898:Borrelia / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D016000:Cluster Analysis; D016172:DNA Fingerprinting / Q000379:methods*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D021901:DNA, Intergenic; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008969:Molecular Sequence Data; D058889:Molecular Typing / Q000379:methods*; D010802:Phylogeny; D011247:Pregnancy; D012061:Relapsing Fever / Q000382:microbiology*; D017422:Sequence Analysis, DNA
D004269:DNA, Bacterial; D021901:DNA, Intergenic