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Didier Raoult - One of the best experts on this subject based on the ideXlab platform.

  • Multispacer Sequence Typing Relapsing Fever Borreliae in Africa
    2016
    Co-Authors: Elbir Haitham, Kassahun Desalegn Bilcha, Jemal Ali, Sally J Cutler, Grégory Gimenez, Cheikh Sokhna, Didier Raoult, Stephen C Barker, Michel Drancourt
    Abstract:

    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. Methodology/Principal Findings: 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/Significance: 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 genotypin

  • The Genome of Borrelia recurrentis, the Agent of Deadly Louse-Borne Relapsing Fever, Is a Degraded Subset of
    2016
    Co-Authors: Tick-borne Borrelia Duttonii, Magali Lescot, Catherine Robert, Thi Tien Nguyen, Guillaume Blanc, Sally J, Patrick Wincker, Arnaud Couloux, Jean-michel Claverie, Didier Raoult
    Abstract:

    In an effort to understand how a tick-borne pathogen adapts to the body louse, we sequenced and compared the genomes of the recurrent fever agents Borrelia recurrentis and B. duttonii. The 1,242,163–1,574,910-bp fragmented genomes of B. recurrentis and B. duttonii contain a unique 23-kb linear plasmid. This linear plasmid exhibits a large polyT track within the promoter region of an intact variable large protein gene and a telomere resolvase that is unique to Borrelia. The genome content is characterized by several repeat families, including antigenic lipoproteins. B. recurrentis exhibited a 20.4 % genome size reduction and appeared to be a strain of B. duttonii, with a decaying genome, possibly due to the accumulation of genomic errors induced by the loss of recA and mutS. Accompanying this were increases in the number of impaired genes and a reduction in coding capacity, including surface-exposed lipoproteins and putative virulence factors. Analysis of the reconstructed ancestral sequence compared to B. duttonii and B. recurrentis was consistent with the accelerated evolution observed in B. recurrentis. Vector specialization of louse-borne pathogens responsible for major epidemics was associated with rapid genome reduction. The correlation between gene loss and increased virulence of B. recurrentis parallels that o

  • a new clade of african body and head lice infected by bartonella quintana and yersinia pestis democratic republic of the congo
    American Journal of Tropical Medicine and Hygiene, 2015
    Co-Authors: Rezak Drali, Georges Diatta, Jeanchristophe Shako, B Davoust, Didier Raoult
    Abstract:

    Abstract The human body louse is known as a vector for the transmission of three serious diseases—specifically, epidemic typhus, trench fever, and relapsing fever caused by Rickettsia prowazekii, Bartonella quintana, and Borrelia recurrentis, respectively—that have killed millions of people. It is also suspected in the transmission of a fourth pathogen, Yersinia pestis, which is the etiologic agent of plague. To date, human lice belonging to the genus Pediculus have been classified into three mitochondrial clades: A, B, and C. Here, we describe a fourth mitochondrial clade, Clade D, comprising head and body lice. Clade D may be a vector of B. quintana and Y. pestis, which is prevalent in a highly plague-endemic area near the Rethy Health District, Orientale Province, Democratic Republic of the Congo.

  • EXPERIMENTAL INFECTION OF HUMAN BODY LICE WITH ACINETOBACTER BAUMANNII
    2015
    Co-Authors: Linda Houhamdi, Didier Raoult
    Abstract:

    Abstract. The human body louse is currently recognized as a vector of Rickettsia prowazekii, Borrelia recurrentis, and Bartonella quintana. Previous studies have reported the isolation of Acinetobacter baumannii from the body lice of homeless patients. To study how the body louse acquires A. baumannii, we infected a rabbit by infusing 2 × 106 colony-forming units of the louse strain of A. baumannii. Two hundred body lice were infected by feeding on the bacteremic rabbit and compared with 200 uninfected lice and two groups of 200 lice feeding on rabbits infected either with another strain of A. baumannii or A. lwoffii. Each louse group received maintenance feedings once a day on another seronegative rabbit. Body lice that fed on rabbits infused with each Acinetobacter species demonstrated a generalized infection. The body lice did not transmit their infection to the nurse rabbit by bite while feeding or to their progeny (eggs and larvae). The lice excreted living Acinetobacter species within their feces. Only the louse strain of A. baumannii was pathogenic for the body louse. An increased mortality rate was observed between the second and third days post-infection; however, they remained infected for their lifespan

  • DISPATCHES Human Pathogens in Body and Head Lice Pierre-Edouard Fournier,*
    2013
    Co-Authors: Jeanbosco Ndihokubwayo, Jo Guidran, Patrick J. Kelly, Didier Raoult
    Abstract:

    Using polymerase chain reaction and sequencing, we investigated the prevalence of Rickettsia prowazekii, Bartonella quintana, and Borrelia recurrentis in 841 body lice collected from various countries. We detected R. prowazekii in body lice from Burundi in 1997 and in lice from Burundi and Rwanda in 2001; B. quintana infections of body lice were widespread. We did not detect B. recurrentis in any lice. T he body louse, Pediculus humanus corporis, is the vector of three human pathogens: Rickettsia prowazekii, the agent of epidemic typhus; Borrelia recurrentis, the agent of relapsing fever; and Bartonella quintana, the agent of trench fever, bacillary angiomatosis, endocarditis, chronic bacteremia, and chronic lymphadenopathy (1). Louse-borne diseases can be associated with high incidence of disease and death, especially epidemic typhus and relapsing fever, which can be fatal in up to 40 % of patients (2). The diseases are mostly prevalent in people living in poverty and overcrowded conditions, for example, homeless people and those involved in war situations (2). Epidemic typhus, trench fever, and relapsing fever have been the subject of many studies, most of which were conducted between World War I and the 1960s. However, medical interest in the diseases and lice waned for almost 30 years. Since 1995 louse-borne diseases have had a dramatic resurgence, and trench fever has been diagnosed in many countrie

Sally J Cutler - One of the best experts on this subject based on the ideXlab platform.

  • Multiplex Real-Time PCR Diagnostic of Relapsing Fevers in Africa
    2016
    Co-Authors: Haitham Elbir, Kassahun Desalegn Bilcha, Sally J Cutler, Oleg Mediannikov, Cheikh Sokhna, Georges Diatta, Mireille Henry, Adama Tall, Cristina Socolovschi, Jemal Ali
    Abstract:

    Background: In Africa, relapsing fever Borreliae are neglected arthropod-borne pathogens causing mild to deadly septicemia and miscarriage. The closely related Borrelia crocidurae, Borrelia duttonii, Borrelia recurrentis and Borrelia hispanica are rarely diagnosed at the species level, hampering refined epidemiological and clinical knowledge of the relapsing fevers. It would be hugely beneficial to have simultaneous detection and identification of Borrelia to species level directly from clinical samples. Methodology/Principal Findings: We designed a multiplex real-time PCR protocol targeting the 16S rRNA gene detecting all four Borrelia, the glpQ gene specifically detecting B. crocidurae, the recN gene specifically detecting B. duttonii/B. recurrentis and the recC gene specifically detecting B. hispanica. Compared to combined 16S rRNA gene and flaB gene sequencing as the gold standard, multiplex real-time PCR analyses of 171 Borrelia-positive and 101 Borrelia-negative control blood specimens yielded 100 % sensitivity and specificity for B. duttonii/B. recurrentis and B. hispanica and 99 % sensitivity and specificity for B. crocidurae. Conclusions/Significance: The multiplex real-time PCR developed in this study is a rapid technique for both molecular detection and speciation of relapsing fever Borreliae from blood in Africa. It could be incorporated in point-of-care laboratory to confirm diagnosis and provide evidence of the burden of infection attributed to different species of known o

  • Multispacer Sequence Typing Relapsing Fever Borreliae in Africa
    2016
    Co-Authors: Elbir Haitham, Kassahun Desalegn Bilcha, Jemal Ali, Sally J Cutler, Grégory Gimenez, Cheikh Sokhna, Didier Raoult, Stephen C Barker, Michel Drancourt
    Abstract:

    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. Methodology/Principal Findings: 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/Significance: 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 genotypin

  • multiplex real time pcr diagnostic of relapsing fevers in africa
    PLOS Neglected Tropical Diseases, 2013
    Co-Authors: Haitham Elbir, Sally J Cutler, Oleg Mediannikov, Cheikh Sokhna, Georges Diatta, Mireille Henry, Adama Tall, Cristina Socolovschi, Kassahun Desalegn Bilcha
    Abstract:

    Background: In Africa, relapsing fever Borreliae are neglected arthropod-borne pathogens causing mild to deadly septicemia and miscarriage. The closely related Borrelia crocidurae, Borrelia duttonii, Borrelia recurrentis and Borrelia hispanica are rarely diagnosed at the species level, hampering refined epidemiological and clinical knowledge of the relapsing fevers. It would be hugely beneficial to have simultaneous detection and identification of Borrelia to species level directly from clinical samples. Methodology/Principal Findings: We designed a multiplex real-time PCR protocol targeting the 16S rRNA gene detecting all four Borrelia, the glpQ gene specifically detecting B. crocidurae, the recN gene specifically detecting B. duttonii/B. recurrentis and the recC gene specifically detecting B. hispanica. Compared to combined 16S rRNA gene and flaB gene sequencing as the gold standard, multiplex real-time PCR analyses of 171 Borrelia-positive and 101 Borrelia-negative control blood specimens yielded 100% sensitivity and specificity for B. duttonii/B. recurrentis and B. hispanica and 99% sensitivity and specificity for B. crocidurae. Conclusions/Significance: The multiplex real-time PCR developed in this study is a rapid technique for both molecular detection and speciation of relapsing fever Borreliae from blood in Africa. It could be incorporated in point-of-care laboratory to confirm diagnosis and provide evidence of the burden of infection attributed to different species of known or potentially novel relapsing fever Borreliae.

  • multispacer sequence typing relapsing fever Borreliae in africa
    PLOS Neglected Tropical Diseases, 2012
    Co-Authors: Elbir Haitham, Kassahun Desalegn Bilcha, Sally J Cutler, Grégory Gimenez, Cheikh Sokhna, Didier Raoult, Stephen C Barker, Michel Drancourt
    Abstract:

    In Africa, relapsing fevers are caused by four cultured species: Borrelia crocidurae, Borrelia duttonii, Borrelia hispanica and Borrelia recurrentis. These Borreliae are transmitted by the bite of Ornithodoros soft ticks except for B. recurrentis which is transmitted by louse Pediculus humanus. They cause potentially undifferentiated fever infection and co-infection with malaria could also occur. The exact prevalence of each Borrelia is unknown and overlaps between B. duttonii and B. crocidurae have been reported. The lack of tools for genotyping these Borreliae limits knowledge concerning their epidemiology. We developed multispacer sequence typing (MST) and applied it to blood specimens infected by B. recurrentis (30 specimens), B. duttonii (18 specimens) and B. crocidurae (13 specimens), delineating these 60 strains and the 3 type strains into 13 species-specific spacer types. B. crocidurae strains were classified into 8 spacer types, B. duttonii into 3 spacer types and B. recurrentis into 2 spacer types. These findings provide the proof-of-concept that that MST is a reliable tool for identification and genotyping relapsing fever Borreliae in Africa.

  • Multispacer Sequence Typing Relapsing Fever Borreliae in Africa
    PLoS Neglected Tropical Diseases, 2012
    Co-Authors: Elbir Haitham, Kassahun Desalegn Bilcha, Jemal Ali, Sally J Cutler, Grégory Gimenez, Cheikh Sokhna, Michel Drancourt
    Abstract:

    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. Methodology/Principal Findings: 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/Significance: 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.

Michel Drancourt - One of the best experts on this subject based on the ideXlab platform.

  • the role of louse transmitted diseases in historical plague pandemics
    Lancet Infectious Diseases, 2020
    Co-Authors: Remi Barbieri, Michel Drancourt
    Abstract:

    Summary The rodent-murine ectoparasite-human model of plague transmission does not correspond with historical details around plague pandemics in Europe. New analysis of ancient genomes reveal that Yersinia pestis was unable to be transmitted by rat fleas until around 4000 Before Present, which challenges the rodent-murine ectoparasite-human model of plague transmission and historical details around plague pandemics in Europe. In this Review, we summarise data regarding Y pestis transmission by human lice in the context of genomic evolution and co-transmission of other major epidemic deadly pathogens throughout human history, with the aim of broadening our view of plague transmission. Experimental models support the efficiency of human lice as plague vectors through infected faeces, which suggest that Y pestis could be a louse-borne disease, similar to Borrelia recurrentis, Rickettsia prowazekii, and Bartonella quintana. Studies have shown that louse-borne outbreaks often involve multiple pathogens, and several cases of co-transmission of Y pestis and B quintana have been reported. Furthermore, an exclusive louse-borne bacterium, namely B recurrentis, was found to be circulating in northern Europe during the second plague pandemic (14th–18th century). Current data make it possible to attribute large historical pandemics to multiple bacteria, and suggests that human lice probably played a preponderant role in the interhuman transmission of plague and pathogen co-transmission during previous large epidemics, including plague pandemics.

  • an outbreak of relapsing fever unmasked by microbial paleoserology 16th century france
    American Journal of Physical Anthropology, 2020
    Co-Authors: Hamadou Oumarou Hama, Remi Barbieri, Jacqueline Guirou, Thomas Chenal, Aurelie Mayer, Yann Ardagna, Michel Signoli, Gerard Aboudharam, Michel Drancourt
    Abstract:

    OBJECTIVES Depicting past epidemics currently relies on DNA-based detection of pathogens, an approach limited to pathogens with well-preserved DNA sequences. We used paleoserology as a complementary approach detecting specific antibodies under a mini line-blot format including positive and negative control antigens. METHODS Mini line blot assay incorporated skim milk as negative control, Staphylococcus aureus as positive control, and antigens prepared from lice-borne pathogens Rickettsia prowazekii, Borrelia recurrentis, Bartonella quintana, and Yersinia pestis. Paleoserums were extracted from rehydrated dental pulp recovered from buried individuals. Mini line blots observed with the naked eye, were quantified using a scanner and appropriate software. Paleoserology was applied to the indirect detection of lice-borne pathogens in seven skeletons exhumed from a 16th-17th century suspected military burial site (Auxi-le-Château); and 14 civils exhumed from a 5th-13th century burial site (Saint-Mont). Direct detection of pathogens was performed using quantitative real-time PCR. RESULTS In Auxi-le-Château, paleoserology yielded 7/7 interpretable paleoserums including 7/7 positives for B. recurrentis including one also positive for B. quintana. In Saint-Mont, paleoserology yielded 8/14 interpretable paleoserums and none reacted against any of the four pathogens. Antibodies against R. prowazekii and Y. pestis were not detected. The seroprevalence was significantly higher in the military burial site of Auxi-le-Château than in the civil burial site of Saint-Mont. Real-time PCR detection of B. quintana yielded 5/21 positive (3 at Saint-Mont and 2 at Auxi-le-Château) whereas B. recurrentis was not detected. CONCLUSIONS Paleoserology unmasked an outbreak of relapsing B. recurrentis fever in one 16th - 17th century military garrison, missed by real-time PCR. Paleoserology offers a new tool for investigating past epidemics, in complement to DNA sequence-based approaches.

  • Multispacer Sequence Typing Relapsing Fever Borreliae in Africa
    2016
    Co-Authors: Elbir Haitham, Kassahun Desalegn Bilcha, Jemal Ali, Sally J Cutler, Grégory Gimenez, Cheikh Sokhna, Didier Raoult, Stephen C Barker, Michel Drancourt
    Abstract:

    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. Methodology/Principal Findings: 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/Significance: 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 genotypin

  • multispacer sequence typing relapsing fever Borreliae in africa
    PLOS Neglected Tropical Diseases, 2012
    Co-Authors: Elbir Haitham, Kassahun Desalegn Bilcha, Sally J Cutler, Grégory Gimenez, Cheikh Sokhna, Didier Raoult, Stephen C Barker, Michel Drancourt
    Abstract:

    In Africa, relapsing fevers are caused by four cultured species: Borrelia crocidurae, Borrelia duttonii, Borrelia hispanica and Borrelia recurrentis. These Borreliae are transmitted by the bite of Ornithodoros soft ticks except for B. recurrentis which is transmitted by louse Pediculus humanus. They cause potentially undifferentiated fever infection and co-infection with malaria could also occur. The exact prevalence of each Borrelia is unknown and overlaps between B. duttonii and B. crocidurae have been reported. The lack of tools for genotyping these Borreliae limits knowledge concerning their epidemiology. We developed multispacer sequence typing (MST) and applied it to blood specimens infected by B. recurrentis (30 specimens), B. duttonii (18 specimens) and B. crocidurae (13 specimens), delineating these 60 strains and the 3 type strains into 13 species-specific spacer types. B. crocidurae strains were classified into 8 spacer types, B. duttonii into 3 spacer types and B. recurrentis into 2 spacer types. These findings provide the proof-of-concept that that MST is a reliable tool for identification and genotyping relapsing fever Borreliae in Africa.

  • Multispacer Sequence Typing Relapsing Fever Borreliae in Africa
    PLoS Neglected Tropical Diseases, 2012
    Co-Authors: Elbir Haitham, Kassahun Desalegn Bilcha, Jemal Ali, Sally J Cutler, Grégory Gimenez, Cheikh Sokhna, Michel Drancourt
    Abstract:

    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. Methodology/Principal Findings: 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/Significance: 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.

Kassahun Desalegn Bilcha - One of the best experts on this subject based on the ideXlab platform.

  • Multiplex Real-Time PCR Diagnostic of Relapsing Fevers in Africa
    2016
    Co-Authors: Haitham Elbir, Kassahun Desalegn Bilcha, Sally J Cutler, Oleg Mediannikov, Cheikh Sokhna, Georges Diatta, Mireille Henry, Adama Tall, Cristina Socolovschi, Jemal Ali
    Abstract:

    Background: In Africa, relapsing fever Borreliae are neglected arthropod-borne pathogens causing mild to deadly septicemia and miscarriage. The closely related Borrelia crocidurae, Borrelia duttonii, Borrelia recurrentis and Borrelia hispanica are rarely diagnosed at the species level, hampering refined epidemiological and clinical knowledge of the relapsing fevers. It would be hugely beneficial to have simultaneous detection and identification of Borrelia to species level directly from clinical samples. Methodology/Principal Findings: We designed a multiplex real-time PCR protocol targeting the 16S rRNA gene detecting all four Borrelia, the glpQ gene specifically detecting B. crocidurae, the recN gene specifically detecting B. duttonii/B. recurrentis and the recC gene specifically detecting B. hispanica. Compared to combined 16S rRNA gene and flaB gene sequencing as the gold standard, multiplex real-time PCR analyses of 171 Borrelia-positive and 101 Borrelia-negative control blood specimens yielded 100 % sensitivity and specificity for B. duttonii/B. recurrentis and B. hispanica and 99 % sensitivity and specificity for B. crocidurae. Conclusions/Significance: The multiplex real-time PCR developed in this study is a rapid technique for both molecular detection and speciation of relapsing fever Borreliae from blood in Africa. It could be incorporated in point-of-care laboratory to confirm diagnosis and provide evidence of the burden of infection attributed to different species of known o

  • Multispacer Sequence Typing Relapsing Fever Borreliae in Africa
    2016
    Co-Authors: Elbir Haitham, Kassahun Desalegn Bilcha, Jemal Ali, Sally J Cutler, Grégory Gimenez, Cheikh Sokhna, Didier Raoult, Stephen C Barker, Michel Drancourt
    Abstract:

    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. Methodology/Principal Findings: 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/Significance: 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 genotypin

  • The Study
    2013
    Co-Authors: In Head Lice, Kassahun Desalegn Bilcha, Jemal Ali, Amina Boutellis, Oleg Mediannikov, Dayana Campelo, Didier Raoult
    Abstract:

    Since the 1800s, the only known vector of Borrelia recurrentis has been the body louse. In 2011, we found B. recurrentis DNA in 23 % of head lice from patients with louse-borne relapsing fever in Ethiopia. Whether head lice can transmit these bacteria from one person to another remains to be determined. Humans are the sole hosts of the pubic louse (Pthirus pubis), the body louse (Pediculus humanus humanus), and the head louse (Pediculus humanus capitis) (1). The body louse can transmit the following life-threatening forms of bacteria to humans: Rickettsia prowazekii, which causes epidemic typhus; Bartonella quintana, which causes trench fever; and Borrelia recurrentis, which causes louseborne relapsing fever (2). Recently, DNA from B. quintana has been found in head lice from Nepal (3), the Unite

  • multiplex real time pcr diagnostic of relapsing fevers in africa
    PLOS Neglected Tropical Diseases, 2013
    Co-Authors: Haitham Elbir, Sally J Cutler, Oleg Mediannikov, Cheikh Sokhna, Georges Diatta, Mireille Henry, Adama Tall, Cristina Socolovschi, Kassahun Desalegn Bilcha
    Abstract:

    Background: In Africa, relapsing fever Borreliae are neglected arthropod-borne pathogens causing mild to deadly septicemia and miscarriage. The closely related Borrelia crocidurae, Borrelia duttonii, Borrelia recurrentis and Borrelia hispanica are rarely diagnosed at the species level, hampering refined epidemiological and clinical knowledge of the relapsing fevers. It would be hugely beneficial to have simultaneous detection and identification of Borrelia to species level directly from clinical samples. Methodology/Principal Findings: We designed a multiplex real-time PCR protocol targeting the 16S rRNA gene detecting all four Borrelia, the glpQ gene specifically detecting B. crocidurae, the recN gene specifically detecting B. duttonii/B. recurrentis and the recC gene specifically detecting B. hispanica. Compared to combined 16S rRNA gene and flaB gene sequencing as the gold standard, multiplex real-time PCR analyses of 171 Borrelia-positive and 101 Borrelia-negative control blood specimens yielded 100% sensitivity and specificity for B. duttonii/B. recurrentis and B. hispanica and 99% sensitivity and specificity for B. crocidurae. Conclusions/Significance: The multiplex real-time PCR developed in this study is a rapid technique for both molecular detection and speciation of relapsing fever Borreliae from blood in Africa. It could be incorporated in point-of-care laboratory to confirm diagnosis and provide evidence of the burden of infection attributed to different species of known or potentially novel relapsing fever Borreliae.

  • Borrelia recurrentis in head lice ethiopia
    Emerging Infectious Diseases, 2013
    Co-Authors: Amina Boutellis, Kassahun Desalegn Bilcha, Jemal Ali, Oleg Mediannikov, Dayana Campelo, Stephen C Barker, Didier Raoult
    Abstract:

    Since the 1800s, the only known vector of Borrelia recurrentis has been the body louse. In 2011, we found B. recurrentis DNA in 23% of head lice from patients with louse-borne relapsing fever in Ethiopia. Whether head lice can transmit these bacteria from one person to another remains to be determined.

Markus M. Simon - One of the best experts on this subject based on the ideXlab platform.

  • Mapping the Ligand-Binding Region of Borrelia hermsii Fibronectin-Binding Protein
    PLOS ONE, 2013
    Co-Authors: Christiane Brenner, Katharina Bomans, Jüri Habicht, Markus M. Simon
    Abstract:

    Many pathogenic microorganisms express fibronectin-binding molecules that facilitate their adherence to the extracellular matrix and/or entry into mammalian cells. We have previously described a Borrelia recurrentis gene, cihC that encodes a 40-kDa surface receptor for both, fibronectin and the complement inhibitors C4bp and C1-Inh. We now provide evidence for the expression of a group of highly homologues surface proteins, termed FbpA, in three B. hermsii isolates and two tick-borne relapsing fever spirochetes, B. parkeri and B. turicatae. When expressed in Escherichia coli or B. burgdorferi, four out of five proteins were shown to selectively bind fibronectin, whereas none of five proteins were able to bind the human complement regulators, C4bp and C1-Inh. By applying deletion mutants of the B. hermsii fibronectin-binding proteins a putative high-affinity binding site for fibronectin was mapped to its central region. In addition, the fibronectin-binding proteins of B. hermsii were found to share sequence homology with BBK32 of the Lyme disease spirochete B. burgdorferi with similar function suggesting its involvement in persistence and/or virulence of relapsing fever spirochetes.

  • human complement regulators c4b binding protein and c1 esterase inhibitor interact with a novel outer surface protein of Borrelia recurrentis
    PLOS Neglected Tropical Diseases, 2010
    Co-Authors: Sonja Grosskinsky, Christiane Brenner, Markus M. Simon, Melanie Schott, Reinhard Wallich
    Abstract:

    The spirochete Borrelia recurrentis is the causal agent of louse-borne relapsing fever and is transmitted to humans by the infected body louse Pediculus humanus. We have recently demonstrated that the B. recurrentis surface receptor, HcpA, specifically binds factor H, the regulator of the alternative pathway of complement activation, thereby inhibiting complement mediated bacteriolysis. Here, we show that B. recurrentis spirochetes express another potential outer membrane lipoprotein, termed CihC, and acquire C4b-binding protein (C4bp) and human C1 esterase inhibitor (C1-Inh), the major inhibitors of the classical and lectin pathway of complement activation. A highly homologous receptor for C4bp was also found in the African tick-borne relapsing fever spirochete B. duttonii. Upon its binding to B. recurrentis or recombinant CihC, C4bp retains its functional potential, i.e. facilitating the factor I-mediated degradation of C4b. The additional finding that ectopic expression of CihC in serum sensitive B. burgdorferi significantly increased spirochetal resistance against human complement suggests this receptor to substantially contribute, together with other known strategies, to immune evasion of B. recurrentis.

  • Human Complement Regulators C4b-Binding Protein and C1 Esterase Inhibitor Interact with a Novel Outer Surface Protein of Borrelia recurrentis
    2009
    Co-Authors: Sonja Grosskinsky, Christiane Brenner, Sally J Cutler, Melanie Schott, Markus M. Simon
    Abstract:

    The spirochete Borrelia recurrentis is the causal agent of louse-borne relapsing fever and is transmitted to humans by the infected body louse Pediculus humanus. We have recently demonstrated that the B. recurrentis surface receptor, HcpA, specifically binds factor H, the regulator of the alternative pathway of complement activation, thereby inhibiting complement mediated bacteriolysis. Here, we show that B. recurrentis spirochetes express another potential outer membrane lipoprotein, termed CihC, and acquire C4b-binding protein (C4bp) and human C1 esterase inhibitor (C1-Inh), the major inhibitors of the classical and lectin pathway of complement activation. A highly homologous receptor for C4bp was also found in the African tick-borne relapsing fever spirochete B. duttonii. Upon its binding to B. recurrentis or recombinant CihC, C4bp retains its functional potential, i.e. facilitating the factor I-mediated degradation of C4b. The additional finding that ectopic expression of CihC in serum sensitive B. burgdorferi significantly increased spirochetal resistance against human complement suggests this receptor to substantially contribute, together with other known strategies, to immune evasion o

  • Borrelia recurrentis employs a novel multifunctional surface protein with anti-complement, anti-opsonic and invasive potential to escape innate immunity
    2009
    Co-Authors: Sonja Grosskinsky, Christiane Brenner, Sally J Cutler, Markus M. Simon, Melanie Schott, Peter Kraiczy, Peter F. Zipfel, Reinhard Wallich
    Abstract:

    Borrelia recurrentis, the etiologic agent of louse-borne relapsing fever in humans, has evolved strategies, including antigenic variation, to evade immune defence, thereby causing severe diseases with high mortality rates. Here we identify for the first time a multifunctional surface lipoprotein of B. recurrentis, termed HcpA, and demonstrate that it binds human complement regulators, Factor H, CFHR-1, and simultaneously, the host protease plasminogen. Cell surface bound factor H was found to retain its activity and to confer resistance to complement attack. Moreover, ectopic expression of HcpA in a B. burgdorferi B313 strain, deficient in Factor H binding proteins, protected the transformed spirochetes from complement-mediated killing. Furthermore, HcpA-bound plasminogen/plasmin endows B. recurrentis with the potential to resist opsonization and to degrade extracellular matrix components. Together, the present study underscores the high virulence potential of B. recurrentis. The elucidation of the molecular basis underlying the versatile strategies of B. recurrentis to escape innate immunity and to persist in human tissues, including the brain, may help to understand the pathological processe