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Didier Raoult - One of the best experts on this subject based on the ideXlab platform.
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Detection of bacterial pathogens including potential new species in human head lice from Mali
PLoS ONE, 2017Co-Authors: Nadia Amanzougaghene, Florence Fenollar, Didier Raoult, Abdoul Karim Sangare, Mahamadou S. Sissoko, Ogobara K. Doumbo, Oleg MediannikovAbstract:In poor African countries, where no medical and biological facilities are available, the identification of potential emerging pathogens of concern at an early stage is challenging. Head lice, Pediculus humanus capitis, have a short life, feed only on human blood and do not transmit pathogens to their progeny. They are, therefore, a perfect tool for the xenodiagnosis of current or recent human infection. This study assessed the occurrence of bacterial pathogens from head lice collected in two rural villages from Mali, where a high frequency of head lice infestation had previously been reported, using molecular methods. Results show that all 600 head lice, collected from 117 individuals, belonged to clade E, specific to West Africa. Bartonella quintana, the causative agent of trench fever, was identified in three of the 600 (0.5%) head lice studied. Our study also shows, for the first time, the presence of the DNA of two pathogenic bacteria, namely Coxiella burnetii (5.1%) and Rickettsia aeschlimannii (0.6%), detected in human head lice, as well as the DNA of potential new species from the Anaplasma and Ehrlichia genera of unknown pathogenicity. The finding of several Malian head lice infected with B. quintana, C. burnetii, R. aeschlimannii, Anaplasma and Ehrlichia is alarming and highlights the need for active survey programs to define the public health consequences of the detection of these emerging bacterial pathogens in human head lice.
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multiple pathogens including potential new species in tick vectors in cote d ivoire
PLOS Neglected Tropical Diseases, 2016Co-Authors: Cyrille Bile Ehounoud, Adele Kacou Ndouba, Jean David Nguessan, Yaba Louise Achi, Mustapha Dahmani, Nadia Amanzougaghene, Didier Raoult, Florence FenollarAbstract:Background Our study aimed to assess the presence of different pathogens in ticks collected in two regions in Cote d'Ivoire. Methodology/Principal Findings Real-time PCR and standard PCR assays coupled to sequencing were used. Three hundred and seventy eight (378) ticks (170 Amblyomma variegatum, 161 Rhipicepalus microplus, 3 Rhipicephalus senegalensis, 27 Hyalomma truncatum, 16 Hyalomma marginatum rufipes, and 1 Hyalomma impressum) were identified and analyzed. We identified as pathogenic bacteria, Rickettsia africae in Am. variegatum (90%), Rh. microplus (10%) and Hyalomma spp. (9%), Rickettsia aeschlimannii in Hyalomma spp. (23%), Rickettsia massiliae in Rh. senegalensis (33%) as well as Coxiella burnetii in 0.2%, Borrelia sp. in 0.2%, Anaplasma centrale in 0.2%, Anaplasma marginale in 0.5%, and Ehrlichia ruminantium in 0.5% of all ticks. Potential new species of Borrelia, Anaplasma, and Wolbachia were detected. Candidatus Borrelia africana and Candidatus Borrelia ivorensis (detected in three ticks) are phylogenetically distant from both the relapsing fever group and Lyme disease group borreliae; both were detected in Am. variegatum. Four new genotypes of bacteria from the Anaplasmataceae family were identified, namely Candidatus Anaplasma ivorensis (detected in three ticks), Candidatus Ehrlichia urmitei (in nine ticks), Candidatus Ehrlichia rustica (in four ticks), and Candidatus Wolbachia ivorensis (in one tick). Conclusions/Significance For the first time, we demonstrate the presence of different pathogens such as R. aeschlimannii, C. burnetii, Borrelia sp., A. centrale, A. marginale, and E. ruminantium in ticks in Cote d'Ivoire as well as potential new species of unknown pathogenicity.
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Multiple Pathogens Including Potential New Species in Tick Vectors in Côte d'Ivoire.
Public Library of Science (PLoS), 2016Co-Authors: Cyrille Bile Ehounoud, Yaba Louise Achi, Mustapha Dahmani, Nadia Amanzougaghene, Florence Fenollar, Didier Raoult, Kouassi Patrick Yao, Adèle Kacou N'douba, Jean David N'guessan, Oleg MediannikovAbstract:Our study aimed to assess the presence of different pathogens in ticks collected in two regions in Côte d'Ivoire.Real-time PCR and standard PCR assays coupled to sequencing were used. Three hundred and seventy eight (378) ticks (170 Amblyomma variegatum, 161 Rhipicepalus microplus, 3 Rhipicephalus senegalensis, 27 Hyalomma truncatum, 16 Hyalomma marginatum rufipes, and 1 Hyalomma impressum) were identified and analyzed. We identified as pathogenic bacteria, Rickettsia africae in Am. variegatum (90%), Rh. microplus (10%) and Hyalomma spp. (9%), Rickettsia aeschlimannii in Hyalomma spp. (23%), Rickettsia massiliae in Rh. senegalensis (33%) as well as Coxiella burnetii in 0.2%, Borrelia sp. in 0.2%, Anaplasma centrale in 0.2%, Anaplasma marginale in 0.5%, and Ehrlichia ruminantium in 0.5% of all ticks. Potential new species of Borrelia, Anaplasma, and Wolbachia were detected. Candidatus Borrelia africana and Candidatus Borrelia ivorensis (detected in three ticks) are phylogenetically distant from both the relapsing fever group and Lyme disease group borreliae; both were detected in Am. variegatum. Four new genotypes of bacteria from the Anaplasmataceae family were identified, namely Candidatus Anaplasma ivorensis (detected in three ticks), Candidatus Ehrlichia urmitei (in nine ticks), Candidatus Ehrlichia rustica (in four ticks), and Candidatus Wolbachia ivorensis (in one tick).For the first time, we demonstrate the presence of different pathogens such as R. aeschlimannii, C. burnetii, Borrelia sp., A. centrale, A. marginale, and E. ruminantium in ticks in Côte d'Ivoire as well as potential new species of unknown pathogenicity
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encodes an intracytoplasmic protein
2016Co-Authors: Zuzana Sekeyova, Veronique Roux, Didier RaoultAbstract:‘Gene D ’ is the PS120-protein-encoding gene, first described in Rickettsia conorii and Rickettsia japonica. Sequence analysis of a 3030 bp fragment of ‘gene D ’ in 24 representatives of the genus Rickettsia was carried out to complete phylogenetic analyses previously inferred by comparison of gene sequences encoding citrate synthase, 17 kDa antigen and rOmpA and rOmpB. The phylogenetic relationships between Rickettsiae were inferred from the comparison of both the gene and the derived protein sequences, using the parsimony, neighbour-joining and maximum-likelihood methods. Five distinct groups of Rickettsiae were identified. These were: the Rickettsia massiliae group, including R. massiliae, Bar 29, Rickettsia rhipicephali and Rickettsia aeschlimannii; the Rickettsia rickettsii group containing Rickettsia sibirica, ‘Rickettsia mongolotimonae ’, Rickettsia parkeri, strain S, Rickettsia africae, the R. conorii complex, Rickettsia slovaca, Rickettsia honei, R. rickettsii, R. japonica and Rickettsia montanensis; the group currently containing only Rickettsia helvetica; the Rickettsia akari group including Rickettsia australis, R. akari and the ELB agent; Rickettsia prowazekii and Rickettsia typhi clustered in the typhus group. As significant bootstrap values were obtained for most of the nodes, sequence comparison of ‘gene D ’ should be considered as a complementary approach in phylogenetic studies of Rickettsiae
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Draft Genome Sequence of Rickettsia aeschlimannii, Associated with Hyalomma marginatum Ticks.
Genome Announcements, 2014Co-Authors: Erwin Sentausa, Didier Raoult, Khalid El Karkouri, Caroline Michelle, Pierre-edouard FournierAbstract:Rickettsia aeschlimannii is a tick-associated human pathogen. We report here the draft genome of R. aeschlimannii strain MC16, isolated from Hyalomma marginatum marginatum ticks collected in Morocco.
Pierre-edouard Fournier - One of the best experts on this subject based on the ideXlab platform.
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Draft Genome Sequence of Rickettsia aeschlimannii, Associated with Hyalomma marginatum Ticks.
Genome Announcements, 2014Co-Authors: Erwin Sentausa, Didier Raoult, Khalid El Karkouri, Caroline Michelle, Pierre-edouard FournierAbstract:Rickettsia aeschlimannii is a tick-associated human pathogen. We report here the draft genome of R. aeschlimannii strain MC16, isolated from Hyalomma marginatum marginatum ticks collected in Morocco.
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Mediterranean Spotted Fever and Other Tick-Borne Rickettsioses
Tick-Borne Diseases of Humans, 2014Co-Authors: Pierre-edouard Fournier, Didier RaoultAbstract:Rickettsioses are arthropod-borne infections caused by bacteria belonging to the genus Rickettsia within the family Rickettsiaceae in the order Rickettsiales. Most of these zoonoses are transmitted by ticks, but some are vectored by lice, fleas, or mites. Tick-borne rickettsioses have specific geographic distributions, directly dependent on the distribution of their vectors. These rickettsioses are among the oldest known arthropod-borne diseases. Rocky Mountain spotted fever (RMSF) was first reported in 1899 by Maxcey; its vector, Dermacentor andersoni, was described in 1909. One year later, Conor and Bruch described Mediterranean spotted fever (MSF) in Tunisia. Over the last 12 years, another 10 of these infections have been characterized, including Astrakhan fever, Flinders Island spotted fever (FISF), African tick-bite fever (ATBF), Japanese spotted fever (JSF), tick-borne lymphadenitis (TIBOLA), lymphangitis-associated rickettsiosis (LAR) due to Rickettsia sibirica mongolotimonae, and unnamed infections caused by Rickettsia helvetica, Rickettsia aeschlimannii, Rickettsia parkeri, and “Rickettsia heilongjiangensis.” Thus, many of the tick-borne rickettsioses are considered to be emerging infections. This chapter considers various aspects of tick-borne rickettsioses, including the description of Rickettsiae, their vectors and the relationships between Rickettsiae and ticks, an overview of the various diseases recognized to date, a description of Rickettsiae of unknown pathogenicity, and a report on modern diagnostic tools and treatments used for tick-transmitted rickettsioses.
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Detection of Rickettsia aeschlimannii in Hyalomma marginatum ticks in western Russia
Clinical Microbiology and Infection, 2009Co-Authors: Shpynov Sn, Irina Tarasevich, Rudakov Nv, Y. Tohkov, A. Matushchenko, Pierre-edouard FournierAbstract:Gamaleya Research Institute of Epidemiology andMicrobiology, Moscow, RussiaINTRODUCTIONSFG Rickettsiae are obligate intracellular Gram-negative bacteria. These bacteria are associatedwith arthropods, mainly ticks, and can be trans-mitted to mammals and humans. Ixodid ticks ofthe Hyalomma marginatum species are widelyspread in semi-desert and steppe landscape areasof south-western Russia, in particular in theStavropol region where they have been reportedto bite humans [1]. The main hosts of the larvaeand nymphs of this tick species include severalspecies of wild and domestic birds, the Europeanbrown hare, and four-toed and eared hedgehogs.In contrast, adult ticks parasitise livestock anddomestic dogs, and may attack humans. InRussia, H. marginatum ticks are known to be themain vectors of the Crimean-Congo haemorrhagicfever (CCHF) virus in the southern part of thecountry. In addition, strains of West Nile fevervirus were isolated from H. marginatum tickscollected in the Volga delta in Astrakhan.However, to date, the presence of Rickettsiae inH. marginatum has not been evaluated. In thepresent study, we investigated by PCR thepresence of Rickettsiae in H. marginatum tickscollected in the Stavropol region of Russia.MATERIALS AND METHODS
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Detection of Rickettsia aeschlimannii in Hyalomma marginatum ticks in western Russia
Clinical Microbiology and Infection, 2009Co-Authors: Shpynov Sn, Irina Tarasevich, Rudakov Nv, Y. Tohkov, A. Matushchenko, Didier Raoult, Pierre-edouard FournierAbstract:Gamaleya Research Institute of Epidemiology andMicrobiology, Moscow, RussiaINTRODUCTIONSFG Rickettsiae are obligate intracellular Gram-negative bacteria. These bacteria are associatedwith arthropods, mainly ticks, and can be trans-mitted to mammals and humans. Ixodid ticks ofthe Hyalomma marginatum species are widelyspread in semi-desert and steppe landscape areasof south-western Russia, in particular in theStavropol region where they have been reportedto bite humans [1]. The main hosts of the larvaeand nymphs of this tick species include severalspecies of wild and domestic birds, the Europeanbrown hare, and four-toed and eared hedgehogs.In contrast, adult ticks parasitise livestock anddomestic dogs, and may attack humans. InRussia, H. marginatum ticks are known to be themain vectors of the Crimean-Congo haemorrhagicfever (CCHF) virus in the southern part of thecountry. In addition, strains of West Nile fevervirus were isolated from H. marginatum tickscollected in the Volga delta in Astrakhan.However, to date, the presence of Rickettsiae inH. marginatum has not been evaluated. In thepresent study, we investigated by PCR thepresence of Rickettsiae in H. marginatum tickscollected in the Stavropol region of Russia.MATERIALS AND METHODS
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spotted fever rickettsioses in southern and eastern europe
Fems Immunology and Medical Microbiology, 2007Co-Authors: Philippe Brouqui, Philippe Parola, Pierre-edouard FournierAbstract:Mediterranean spotted fever due to Rickettsia conorii conorii was thought, for many years, to be the only tick-borne Rickettsial disease prevalent in southern and eastern Europe. However, in recent years, six more species or subspecies within the spotted fever group of the genus Rickettsia have been described as emerging pathogens in this part of the world. Tick-borne agents include Rickettsia conorii israelensis, Rickettsia conorii caspia, Rickettsia aeschlimannii, Rickettsia slovaca, Rickettsia sibirica mongolitimonae and Rickettsia massiliae. Many Rickettsia of unknown pathogenicity have also been detected from ticks and could represent potential emerging pathogens to be discovered in the future. Furthermore, a new spotted fever Rickettsia, Rickettsia felis, was found to be associated with cat fleas and is an emerging human pathogen. Finally, the mite-transmitted Rickettsia akari, the agent of Rickettsialpox, is also known to be prevalent in Europe. We present here an overview of these rickettsioses, focusing on emerging diseases.
Irina Tarasevich - One of the best experts on this subject based on the ideXlab platform.
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Detection of Rickettsia aeschlimannii in Hyalomma marginatum ticks in western Russia
Clinical Microbiology and Infection, 2009Co-Authors: Shpynov Sn, Irina Tarasevich, Rudakov Nv, Y. Tohkov, A. Matushchenko, Pierre-edouard FournierAbstract:Gamaleya Research Institute of Epidemiology andMicrobiology, Moscow, RussiaINTRODUCTIONSFG Rickettsiae are obligate intracellular Gram-negative bacteria. These bacteria are associatedwith arthropods, mainly ticks, and can be trans-mitted to mammals and humans. Ixodid ticks ofthe Hyalomma marginatum species are widelyspread in semi-desert and steppe landscape areasof south-western Russia, in particular in theStavropol region where they have been reportedto bite humans [1]. The main hosts of the larvaeand nymphs of this tick species include severalspecies of wild and domestic birds, the Europeanbrown hare, and four-toed and eared hedgehogs.In contrast, adult ticks parasitise livestock anddomestic dogs, and may attack humans. InRussia, H. marginatum ticks are known to be themain vectors of the Crimean-Congo haemorrhagicfever (CCHF) virus in the southern part of thecountry. In addition, strains of West Nile fevervirus were isolated from H. marginatum tickscollected in the Volga delta in Astrakhan.However, to date, the presence of Rickettsiae inH. marginatum has not been evaluated. In thepresent study, we investigated by PCR thepresence of Rickettsiae in H. marginatum tickscollected in the Stavropol region of Russia.MATERIALS AND METHODS
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Detection of Rickettsia aeschlimannii in Hyalomma marginatum ticks in western Russia
Clinical Microbiology and Infection, 2009Co-Authors: Shpynov Sn, Irina Tarasevich, Rudakov Nv, Y. Tohkov, A. Matushchenko, Didier Raoult, Pierre-edouard FournierAbstract:Gamaleya Research Institute of Epidemiology andMicrobiology, Moscow, RussiaINTRODUCTIONSFG Rickettsiae are obligate intracellular Gram-negative bacteria. These bacteria are associatedwith arthropods, mainly ticks, and can be trans-mitted to mammals and humans. Ixodid ticks ofthe Hyalomma marginatum species are widelyspread in semi-desert and steppe landscape areasof south-western Russia, in particular in theStavropol region where they have been reportedto bite humans [1]. The main hosts of the larvaeand nymphs of this tick species include severalspecies of wild and domestic birds, the Europeanbrown hare, and four-toed and eared hedgehogs.In contrast, adult ticks parasitise livestock anddomestic dogs, and may attack humans. InRussia, H. marginatum ticks are known to be themain vectors of the Crimean-Congo haemorrhagicfever (CCHF) virus in the southern part of thecountry. In addition, strains of West Nile fevervirus were isolated from H. marginatum tickscollected in the Volga delta in Astrakhan.However, to date, the presence of Rickettsiae inH. marginatum has not been evaluated. In thepresent study, we investigated by PCR thepresence of Rickettsiae in H. marginatum tickscollected in the Stavropol region of Russia.MATERIALS AND METHODS
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detection of a Rickettsia closely related to Rickettsia aeschlimannii Rickettsia heilongjiangensis Rickettsia sp strain rpa4 and ehrlichia muris in ticks collected in russia and kazakhstan
Journal of Clinical Microbiology, 2004Co-Authors: S N Shpynov, Marat Tankibaev, N. V. Rudakov, Pierre-edouard Fournier, Irina TarasevichAbstract:Using PCR, we screened 411 ticks from four genera collected in Russia and Kazakhstan for the presence of Rickettsiae and ehrlichiae. In Russia, we detected “Rickettsia heilongjiangensis,” Rickettsia sp. strain RpA4, and Ehrlichia muris. In Kazakhstan, we detected Rickettsia sp. strain RpA4 and a Rickettsia closely related to Rickettsia aeschlimannii. These agents should be considered in a differential diagnosis of tick-borne infections in these areas.
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Detection of a Rickettsia Closely Related to Rickettsia aeschlimannii, “Rickettsia heilongjiangensis,” Rickettsia sp. Strain RpA4, and Ehrlichia muris in Ticks Collected in Russia and Kazakhstan
Journal of Clinical Microbiology, 2004Co-Authors: Pierre-edouard Fournier, Irina Tarasevich, Marat Tankibaev, Didier RaoultAbstract:Using PCR, we screened 411 ticks from four genera collected in Russia and Kazakhstan for the presence of Rickettsiae and ehrlichiae. In Russia, we detected “Rickettsia heilongjiangensis,” Rickettsia sp. strain RpA4, and Ehrlichia muris. In Kazakhstan, we detected Rickettsia sp. strain RpA4 and a Rickettsia closely related to Rickettsia aeschlimannii. These agents should be considered in a differential diagnosis of tick-borne infections in these areas.
Oleg Mediannikov - One of the best experts on this subject based on the ideXlab platform.
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molecular identification of protozoal and bacterial organisms in domestic animals and their infesting ticks from north eastern algeria
Ticks and Tick-borne Diseases, 2020Co-Authors: Rima Sadeddine, Souad Righi, Adama Zan Diarra, Maureen Laroche, Ahmed Benakhla, Oleg Mediannikov, Handi DahmanaAbstract:Abstract A molecular survey was undertaken to determine the presence of protozoal and bacterial organisms in 120 ticks and 87 blood samples collected from mammals in north-eastern Algeria. Eight tick species were morphologically identified including 70 Rhipicephalus (Boophilus) annulatus, 23 Rhipicephalus bursa, five Rhipicephalus sanguineus sensu lato, 11 Hyalomma impeltatum, five Hyalomma scupense, two Hyalommma marginatum, one Hyalomma anatolicum and three Ixodes ricinus. Quantitative PCR screening of the ticks showed that Theileria annulata, “Candidatus Ehrlichia urmitei”, Theileria buffeli and Anaplasma platys were detected in Rh. annulatus. Rickettsia massiliae and Anaplasma ovis were detected in Rh. sanguineus s.l. and Rh. bursa. Rickettsia aeschlimannii was detected in Hy. marginatum, Hy. scupense and Hy. impeltatum. Finally, “Candidatus Rickettsia barbariae” was detected in Rh. bursa. In the screening blood samples, Theileria equi, T.annulata, T. buffeli, Babesia bovis, Anaplasma marginale, A. ovis and Borrelia spp. were detected in cattle. Theileria ovis, T. annulata, and A. ovis were detected in sheep. In addition, A. ovis and T. equi were detected in goats and equidea respectively. In this study, T. equi and “Candidatus Rickettsia barbariae” were identified for the first time in Algeria as well as potential new species of Ehrlichia and Anaplasma. Although molecular detection does not indicate vector/reservoir competence when investigating ticks removed from animals, this study expands the knowledge of the microorganisms detected in ticks in north-east of Algeria.
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Detection of bacterial pathogens including potential new species in human head lice from Mali
PLoS ONE, 2017Co-Authors: Nadia Amanzougaghene, Florence Fenollar, Didier Raoult, Abdoul Karim Sangare, Mahamadou S. Sissoko, Ogobara K. Doumbo, Oleg MediannikovAbstract:In poor African countries, where no medical and biological facilities are available, the identification of potential emerging pathogens of concern at an early stage is challenging. Head lice, Pediculus humanus capitis, have a short life, feed only on human blood and do not transmit pathogens to their progeny. They are, therefore, a perfect tool for the xenodiagnosis of current or recent human infection. This study assessed the occurrence of bacterial pathogens from head lice collected in two rural villages from Mali, where a high frequency of head lice infestation had previously been reported, using molecular methods. Results show that all 600 head lice, collected from 117 individuals, belonged to clade E, specific to West Africa. Bartonella quintana, the causative agent of trench fever, was identified in three of the 600 (0.5%) head lice studied. Our study also shows, for the first time, the presence of the DNA of two pathogenic bacteria, namely Coxiella burnetii (5.1%) and Rickettsia aeschlimannii (0.6%), detected in human head lice, as well as the DNA of potential new species from the Anaplasma and Ehrlichia genera of unknown pathogenicity. The finding of several Malian head lice infected with B. quintana, C. burnetii, R. aeschlimannii, Anaplasma and Ehrlichia is alarming and highlights the need for active survey programs to define the public health consequences of the detection of these emerging bacterial pathogens in human head lice.
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Multiple Pathogens Including Potential New Species in Tick Vectors in Côte d'Ivoire.
Public Library of Science (PLoS), 2016Co-Authors: Cyrille Bile Ehounoud, Yaba Louise Achi, Mustapha Dahmani, Nadia Amanzougaghene, Florence Fenollar, Didier Raoult, Kouassi Patrick Yao, Adèle Kacou N'douba, Jean David N'guessan, Oleg MediannikovAbstract:Our study aimed to assess the presence of different pathogens in ticks collected in two regions in Côte d'Ivoire.Real-time PCR and standard PCR assays coupled to sequencing were used. Three hundred and seventy eight (378) ticks (170 Amblyomma variegatum, 161 Rhipicepalus microplus, 3 Rhipicephalus senegalensis, 27 Hyalomma truncatum, 16 Hyalomma marginatum rufipes, and 1 Hyalomma impressum) were identified and analyzed. We identified as pathogenic bacteria, Rickettsia africae in Am. variegatum (90%), Rh. microplus (10%) and Hyalomma spp. (9%), Rickettsia aeschlimannii in Hyalomma spp. (23%), Rickettsia massiliae in Rh. senegalensis (33%) as well as Coxiella burnetii in 0.2%, Borrelia sp. in 0.2%, Anaplasma centrale in 0.2%, Anaplasma marginale in 0.5%, and Ehrlichia ruminantium in 0.5% of all ticks. Potential new species of Borrelia, Anaplasma, and Wolbachia were detected. Candidatus Borrelia africana and Candidatus Borrelia ivorensis (detected in three ticks) are phylogenetically distant from both the relapsing fever group and Lyme disease group borreliae; both were detected in Am. variegatum. Four new genotypes of bacteria from the Anaplasmataceae family were identified, namely Candidatus Anaplasma ivorensis (detected in three ticks), Candidatus Ehrlichia urmitei (in nine ticks), Candidatus Ehrlichia rustica (in four ticks), and Candidatus Wolbachia ivorensis (in one tick).For the first time, we demonstrate the presence of different pathogens such as R. aeschlimannii, C. burnetii, Borrelia sp., A. centrale, A. marginale, and E. ruminantium in ticks in Côte d'Ivoire as well as potential new species of unknown pathogenicity
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Identification of Rickettsial pathogens in ixodid ticks in northern Senegal.
Ticks and Tick-borne Diseases, 2014Co-Authors: Masse Sambou, Georges Diatta, Didier Raoult, Ngor Faye, Hubert Bassene, Oleg MediannikovAbstract:The spotted fevers, caused by the Rickettsia bacteria, are a group of emerging diseases that are responsible for significant human morbidity. In Africa, the distribution of different species of Rickettsia in their tick vectors is poorly studied. We have collected 1169 hard ticks from 5 different species in the northern Senegal, close to the Saharan border. In a far northern collection site, corresponding to the Rickettsia africae distribution area, we collected three Amblyomma variegatum ticks infected by R. africae. Rickettsia africae was also identified in a Hyalomma marginatum rufipes tick, which may represent the secondary host for the pathogen. Rickettsia aeschlimannii was identified in H. m. rufipes, Rhipicephalus evertsi evertsi, and Hyalomma impeltatum ticks.
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Tick-Borne Rickettsioses, Neglected Emerging Diseases
2013Co-Authors: In Rural Senegal, Oleg Mediannikov, Cheikh Sokhna, Florence Fenollar, Georges Diatta, Jean-françois TrapeAbstract:Background: Rickettsioses are one of the most important causes of systemic febrile illness among travelers from developed countries, but little is known about their incidence in indigenous populations, especially in West Africa. Methodology/Principal Findings: Overall seroprevalence evaluated by immunofluorescence using six Rickettsial antigens (spotted fever and typhus group) in rural populations of two villages of the Sine-Saloum region of Senegal was found to be 21.4 % and 51 % for spotted fever group Rickettsiae for Dielmo and Ndiop villages, respectively. We investigated the role of tick-borne Rickettsiae as the cause of acute non-malarial febrile diseases in the same villages. The incidence of Rickettsial DNA in 204 blood samples from 134 (62M and 72F) febrile patients negative for malaria was studied. DNA extracted from whole blood was tested by two qPCR systems. Rickettsial DNA was found in nine patients, eight with Rickettsia felis (separately reported). For the first time in West Africa, Rickettsia conorii was diagnosed in one patient. We also tested 2,767 Ixodid ticks collected in two regions of Senegal (Niakhar and Sine-Saloum) from domestic animals (cows, sheep, goats, donkeys and horses) by qPCR and identified five different pathogenic Rickettsiae. We found the following: Rickettsia aeschlimannii in Hyalomma marginatum rufipes (51.3 % and 44.8 % in Niakhar and Sine-Saloum region, respectively), in Hyalomma truncatum (6 % and 6.8%) and in Rhipicephalus evertsi evertsi (0.5%, only in Niakhar); R. c. conorii in Rh. e. evertsi (0.4%, only in Sine-Saloum); Rickettsia massiliae in Rhipicephalus guilhoni (22.4%, only in Niakhar); Rickettsia sibiric
Philippe Parola - One of the best experts on this subject based on the ideXlab platform.
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Detection of Rickettsia hoogstraalii, Rickettsia helvetica, Rickettsia massiliae, Rickettsia slovaca and Rickettsia aeschlimannii in ticks from Sardinia, Italy.
Ticks and Tick-borne Diseases, 2017Co-Authors: Valentina Chisu, Cipriano Foxi, Giovanna Masala, Hamza Leulmi, Mariano Piredda, Philippe ParolaAbstract:Tick-borne diseases represent a large proportion of infectious diseases that have become a world health concern. The presence of Rickettsia spp. was evaluated by standard PCR and sequencing in 123 ticks collected from several mammals and vegetation in Sardinia, Italy. This study provides the first evidence of the presence of Rickettsia hoogstralii in Haemaphysalis punctata and Haemaphysalis sulcata ticks from mouflon and Rickettsia helvetica in Ixodes festai ticks from hedgehog. In addition, Rickettsia massiliae, Rickettsia slovaca and Rickettsia aeschlimannii were detected in Rhipicephalus sanguineus, Dermacentor marginatus and Hyalomma marginatum marginatum ticks from foxes, swine, wild boars, and mouflon. The data presented here increase our knowledge of tick-borne diseases in Sardinia and provide a useful contribution toward understanding their epidemiology.
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Detection of Rickettsia hoogstraalii, Rickettsia helvetica, Rickettsia massiliae, Rickettsia slovaca and Rickettsia aeschlimannii in ticks from Sardinia, Italy
Ticks and Tick-borne Diseases, 2017Co-Authors: Valentina Chisu, Cipriano Foxi, Giovanna Masala, Hamza Leulmi, Mariano Piredda, Philippe ParolaAbstract:Tick-borne diseases represent a large proportion of infectious diseases that have become a world health concern. The presence of Rickettsia spp. was evaluated by standard PCR and sequencing in 123 ticks collected from several mammals and vegetation in Sardinia, Italy. This study provides the first evidence of the presence of Rickettsia hoogstralii in Haemaphysalis punctata and Haemaphysalis sulcata ticks from mouflon and Rickettsia helvetica in Ixodes festai ticks from hedgehog. In addition, Rickettsia massiliae, Rickettsia slovaca and Rickettsia aeschlimannii were detected in Rhipicephalus sanguineus, Dermacentor marginatus and Hyalomma marginatum marginatum ticks from foxes, swine, wild boars, and mouflon. The data presented here increase our knowledge of tick-borne diseases in Sardinia and provide a useful contribution toward understanding their epidemiology. (C) 2016 Elsevier GmbH. All rights reserved.
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The first molecular detection of Rickettsia aeschlimannii in the ticks of camels from southern Algeria.
Ticks and Tick-borne Diseases, 2012Co-Authors: Amel Djerbouh, Philippe Parola, Didier Raoult, Tahar Kernif, Assia Beneldjouzi, Cristina Socolovschi, Nadia Kechemir, Idir BitamAbstract:We collected ticks from camels in 4 regions of southern Algeria (El Oued, Bechar, Ghardia, and Adrar) from February to October in 2008 and in April of 2011. A total of 307 ticks representing multiple species (including Hyalomma dromedarii, H. marginatum rufipes, H. impeltatum, and H. impressum), was tested for the presence of spotted fever group Rickettsia DNA using gltA real-time quantitative PCR (qPCR). The presence of Rickettsia aeschlimannii was confirmed with a new qPCR using species-specific primers and Taqman probes based on the sca2 genes. The R. aeschlimannii sequence was further confirmed by detecting the gltA and outer membrane protein (ompA) genes in H. m. rufipes, H. impeltatum, and H. dromedarii ticks. These findings represent the first report of the detection of R. aeschlimannii in ticks collected from camels from southern Algeria.
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First detection of Rickettsia aeschlimannii in Hyalomma dromedarii ticks from Tunisia.
Ticks and Tick-borne Diseases, 2012Co-Authors: Jean-paul Demoncheaux, Didier Raoult, Cristina Socolovschi, Bernard Davoust, Slim Haddad, Philippe ParolaAbstract:Tick-borne rickettsioses have long been described in North Africa. These human diseases and their causative agents occur in several countries in this region, including Mauritania, Morocco, Algeria, Tunisia, Libya, and Egypt. In Tunisia, the first described and most well-known rickettsiosis is Mediterranean spotted fever, which is caused by Rickettsia conorii conorii. Cases of R. aeschlimannii infections have been documented by serology, but the agent has never actually been detected in patients or arthropods in the country. In October 2008, ticks were collected from a dromedary (Camelius dromedarii) in Douz, Central Tunisia. All of the ticks were identified as Hyalomma dromedarii and were tested using polymerase chain reaction to determine the presence of Rickettsiae. Our results indicate the first molecular detection of R. aeschlimannii in ticks from Tunisia.
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Rickettsia slovaca from Dermacentor marginatus ticks in Sardinia, Italy.
Ticks and Tick-borne Diseases, 2012Co-Authors: Giovanna Masala, Didier Raoult, Valentina Chisu, Giuseppe Satta, Christina Socolovschi, Philippe ParolaAbstract:Nineteen ticks belonging to the species Dermacentor marginatus, Rhipicephalus bursa, and Haemaphysalis sulcata were collected from wild animals (wild boar, deer, and mouflon) in south-western Sardinia, Italy. Five D. marginatus ticks from wild boar were PCR-positive when analyzed using gltA-specific and ompA-specific primers, leading to the identification and first isolation in cell culture of Rickettsia slovaca, the causative agent of tick-borne lymphadenopathy (TIBOLA), on the island of Sardinia. This study confirms the detection of a new tick-borne Rickettsia that can be added to the others already known to be present in Sardinia (Rickettsia aeschlimannii, R. massiliae, and Candidatus Rickettsia barbariae). These data increase our knowledge of tick-borne rickettsioses in Sardinia and, more generally, in the Mediterranean basin.
