Population Structure of East African Relapsing FeverBorreliaspp.

Abstract

B. recurrentis may have evolved directly from B. duttonii.

Molecular Detection of Fastidious and Common Bacteria as Well as Plasmodium spp. in Febrile and Afebrile Children in Franceville, Gabon

“…[9][10][11][12][13][14][15] Rickettsia felis and Borrelia duttonii were also found in eastern Africa. [16][17][18] Some of them had already been described in Gabon. For example, R. felis and Bartonella quintana had been detected in some well-known vector arthropods.…”

“…In most studies performed in sub-Saharan Africa on febrile patients, the lack of control groups composed of afebrile people represents a major pitfall that compromises a good understanding of causes of fever in areas where asymptomatic carriage of microorganisms are described. 13,17,18,24 Herein, our aim was to use molecular assays to evaluate the prevalence of bacteria, including emerging and common bacteria, as well as the prevalence of Plasmodium spp. in both febrile and afebrile children in Franceville, Gabon, where it has been recently reported that malaria prevalence had decreased from 68.9% to 17.9% among febrile patients.…”

Relapsing Fever Borreliae in Africa

“…Relatively few genetic loci, such as the single-copy chromosomal 16S rRNA and flabB genes 39 and the 16S-23S ribosomal RNA intergenic spacer (IGS), have been used to discriminate between the various African relapsing fever borreliae. 40 Genetic comparisons 18,19 indicate that the 16S rRNA gene exhibits two to six nucleotide differences among the four cultured species; these differences are scattered along the whole 16S rRNA gene sequence for each species, resulting in a high overall sequence similarity of 99.7-99.9% between the four species. 41 Moreover, interrogation of GenBank database indicates that these signatures are not consistent over the 37 B. crocidurae 16S rRNA gene sequences recorded in GenBank, resulting in a 1% 16S rRNA gene sequence intraspecies variation.…”

“…The IGS showed an interspecies sequence variability of 92-99%, making it a potential target to identify borreliae from vectors and from blood. 40 The IGS sequence-based phylogenetic tree clustered B. crocidurae and B. hispanica into one clade and also generated a clade comprising B. duttonii and B. recurrentis. Indeed, IGS sequencing in Tanzania mixed four B. duttonii types with two B. recurrentis types.…”

“…Indeed, IGS sequencing in Tanzania mixed four B. duttonii types with two B. recurrentis types. 40 Because sequencing a single spacer may be inaccurate, we recently developed a multispacer sequence typing (MST) approach and showed that sequencing five appropriate intergenic spacers accurately identified cultured relapsing fever borreliae and revealed diversity among them. 42 These data indicate that no single sequence accurately discriminates between relapsing fever Borrelia and that a combination of multiple sequencing is required.…”