Reservoirs and vectors of bartonellae and rickettsiae in New Caledonia

Les bartonelloses et les rickettsioses sont des infections à transmission vectorielle souvent graves chez l’homme, mais asymptomatiques chez les animaux. Afin d’identifier de potentiels réservoirs et/ou vecteurs d’infections dues à Bartonella spp. et à Rickettsia spp. en Nouvelle-Calédonie, nous avons effectué des prélèvements de sang sur : 64 chiens, 8 chats, 30 bovins, 25 chevaux et 29 cerfs rusa (Rusa timorensis). 329 parasites externes hématophages (tiques, puces, mouches piqueuses) ont été collectés sur ces mêmes animaux. Quatre souches de Bartonella henselae ont été isolées chez les chats (50 %) et six de B. chomelii chez les bovins (20%). Bartonella aff. schoenbuchensis a été détectée chez 31% des cerfs ; Rickettsia felis chez 81% des 21 puces récoltées sur les chiens et B. clarridgeiae dans 1% des puces. Nos études confirment que les infections à bartonelles et rickettsies pourraient devenir une préoccupation croissante de santé publique en Océanie et montrent l’intérêt des nouveaux outils de diagnostic moléculaire pour la compréhension de ces maladies.Bartonellosis and rickettsiosis are vector-borne infections often asymptomatic in animals. In order to identify potential sources and vectors of Bartonella spp. and Rickettsia spp. infection in New Caledonia, we collected blood samples from 64 dogs, 8 cats, 30 cattle, 25 horses and 29 wild deer (Rusa timorensis). 329 associated blood-sucking parasites were also collected. We isolated four strains of Bartonella henselae from cats (50%) and six of Bartonella chomelii from cattle (20%). Deers (31%) were infected by Bartonella aff. schoenbuchensis. Rickettsia felis was detected in 81 % of 21 fleas collected from dogs and Bartonella clarridgeiae in 1% of fleas. Our data confirmed that Bartonella and Rickettsia infections could be an increasing public health concern in Oceania and showed the interest of new molecular diagnostic tools for understanding these diseases

Molecular Investigation and Phylogeny of Species of the \u3ci\u3eAnaplasmataceae\u3c/i\u3e Infecting Animals and Ticks in Senegal

Background: Our study aimed to assess the diversity of the species of Anaplasmataceae in Senegal that infect animals and ticks in three areas: near Keur Momar Sarr (northern region), Dielmo and Diop (Sine Saloum, central region of Senegal), and in Casamance (southern region of Senegal). Methods: A total of 204 ticks and 433 blood samples were collected from ruminants, horses, donkeys and dogs. Ticks were identified morphologically and by molecular characterization targeting the 12S rRNA gene. Molecular characterization of species of Anaplasmataceae infecting Senegalese ticks and animals was conducted using the 23S rRNA, 16S rRNA, rpoB and groEL genes. Results: Ticks were identified as Rhipicephalus evertsi evertsi (84.3%), Hyalomma rufipes (8.3%), Hyalomma impeltatum (4.9%), R. bursa (1.5%) and R. muhsamae (0.9%). The overall prevalence of Anaplasmataceae infection in ticks was 0.9%, whereas 41.1% of the sampled animals were found infected by one of the species belonging to this family. We identified the pathogen Anaplasma ovis in 55.9% of sheep, A. marginale and A. centrale in 19.4% and 8.1%, respectively, of cattle, as well as a putative new species of Anaplasmataceae. Two Anaplasma species commonly infecting ruminants were identified. Anaplasma cf. platys, closely related to A. platys was identified in 19.8% of sheep, 27.7% of goats and 22.6% of cattle, whereas a putative new species, named here provisionally “Candidatus Anaplasma africae”, was identified in 3.7% of sheep, 10.3% of goats and 8.1% of cattle. Ehrlichia canis and Anaplasma platys were identified only from dogs sampled in the Keur Momar Sarr area. Ehrlichia canis was identified in 18.8% of dogs and two R. e. evertsi ticks removed from the same sheep. Anaplasma platys was identified in 15.6% of dogs. Neither of the dogs sampled from Casamance region nor the horses and donkeys sampled from Keur Momar Sarr area were found infected by an Anaplasmataceae species. Conclusions: This study presents a summary of Anaplasmataceae species that infect animals and ticks in three areas from the northern, central and southern regions of Senegal. To our knowledge, our findings demonstrate for the first time the presence of multiple Anaplasmataceae species that infect ticks and domestic animals in Senegal. We recorded two potentially new species commonly infecting ruminants named here provisionally as Anaplasma cf. platys and “Candidatus Anaplasma africae”. However, E. canis was the only species identified and amplified from ticks. None of the other Anaplasmataceae species identified in animals were identified in the tick species collected from animals

Contribution of qPCR in detection of infections of ruminants with Anaplasmataceae: case study in the Basque country and in Corsica

Les Anaplasmataceae sont des bactéries intracellulaires transmises aux animaux et à l’homme, principalement par les tiques. Les Anaplasma spp. (A. marginale, A. phagocytophilum…) et les Ehrlichia spp. (E. canis, E. ruminantium...) en sont les principaux représentants d’importance économique et sanitaire. Les outils de diagnostic disponibles jouent un rôle déterminant dans leur identification. Nous proposons une approche globale par un système permettant d’identifier la plupart des espèces d’Anaplasmataceae. Il est basé sur le gène codant l’ARNr 23S ; il couple une qPCR et une PCR standard avec deux jeux d’amorces suivie d’un séquençage. Il est testé pour en vérifier la spécificité, puis mis en oeuvre à partir de prélèvements de sang de ruminants et de tiques : dans les Pyrénées-Atlantiques, des brebis suspectes d’infection sont porteuses d’A. ovis et leurs tiques Rhipicephalus bursa, d’A. ovis, d’A. phagocytophilum et d’une nouvelle ehrlichia. En Haute-Corse, une forte prévalence d’infections par les Anaplasmataceae est détectée dans des élevages (bovins, ovins, caprins) où la symptomatologie rétrocède lors de traitements à l’oxytétracycline. La spécificité et la sensibilité du système de diagnostic utilisé et sa capacité à identifier de nouvelles espèces offrent des perspectives pour l’étude de l’épidémiologie des Anaplasmataceae et permettront de mettre en évidence de nouveaux réservoirs.The intracelullar bacteria Anaplasmataceae are transmitted by ticks both to animals and to man. The most important species for the economy and for health are Anaplasma spp. (A. marginale, A. phagocytophilum…) and Ehrlichia spp. (E. canis and E. ruminantium...). Whilst current means of diagnosis are indispensible they could be improved. We therefore propose a global approach which will identify most of the species of Anaplasmataceae. It is based on the genetic code ARNr 23S and involves dividing a qPCR into a standard PCR and sequencing. This specificity has been tested, verified and demonstrated in blood samples from ruminants and ticks. Sheep (from Atlantic-Pyrenees) suspected of being infected, were shown to be carriers of A. ovis and their ticks (Rhipicephalus bursa) had A. ovis, A. phagocytophilum and also a new species of ehrlichia. In Corsica, a strong incidence of Anaplasmataceae was detected in the blood of cattle, sheep and goats in which symptoms antedated treatment with oxytetracycline. The specificity and sensibility of this method of diagnosis, as well as its ability to detect new species, are advantageous for further studies of Anaplasmataceae, and facilitate the search for new sources of infection

Anaplasmataceae bacteria as vector-borne pathogens

Dans ce travail, nous nous sommes intéressés à l’étude des infections à Anaplasmataceae chez les animaux et leurs tiques afin de caractériser au mieux ces infections animales et humaines et décrire de nouvelles espèces. Nous avons tout d’abord proposé un système de diagnostic moléculaire qui couple une qPCR suivie d’amplification et un séquençage ciblant le gène 23S ARNr. Puis, au long de ce travail, nous avons proposé d’autres amorces ciblant d’autres gènes incluant la sous unité ribosomal bêta (rpoB), la protéine du choc thermique (groEl), et le 16S ARNr. Notre objectif a été de sélectionner et d’identifier les différentes espèces impliquées ou non dans des pathologies chez les animaux et mettre en évidence leur vecteur. Au cours de ces travaux, nous avons eu accès à différents prélèvements de sang et des tiques en provenance de diverses régions du monde incluant la France métropolitaine et d’outre-mer, l’Algérie, le Niger, la Côte d’Ivoire, le Sénégal et le Pakistan. Nos investigations ont permis d’identifier différentes espèces d’Anaplasmataceae incluant de potentielles nouvelles espèces. Les prévalences rapportées dans chaque étude démontrent que les animaux sont les réservoirs de ces infections. Les recherches menées sur les tiques ont permis d’identifier de potentiels vecteurs d’Anaplasmataceae dans différentes régions du monde. Les potentielles nouvelles espèces identifiées sont caractérisées en ciblant différents gènes, et les analyses moléculaires démontrent qu’elles sont différentes des autres Anaplasmataceae connues jusqu’à maintenant. Ces différents travaux apportent donc davantage d’informations sur l’épidémiologie des Anaplasmataceae dans le monde.In this work, we are interested in studying Anaplasmataceae infections in animals and their ticks. Our objective is to describe these infections in animals and to identify new species implicated in different pathology. First, we propose a molecular diagnostic approach that couples a qPCR followed by amplification and sequencing targeting the 23S rRNA gene. Then we propose other primers targeting other genes including the ribosomal subunit beta (rpoB), heat shock protein (groEl), and the 16S rRNA. Our goal was to screen and identify the different species involved, or not involved, in pathologies of animals and identify their vectors. During this work, we had access to different blood samples and ticks from different parts of the world including metropolitan France, France overseas, Algeria, the Republic of Niger, Côte d'Ivoire, Senegal and Pakistan. Our different investigations allowed to identify different species of Anaplasmataceae including potential new species. The prevalence reported in each study demonstrates that animals are the reservoirs of these infections. So, the research conducted on ticks has identified potential vectors of Anaplasmataceae in different regions of the world. Potentially new species were identified are characterized by different targeting genes. These studies provide further information on the epidemiology of Anaplasmataceae in the world

EPIDEMIOLOGICAL STUDY OF CRYPTOSPORIDIOSIS AND DISEASE-ASSOCIATED FACTORS IN SHEEP IN A STEPPE REGION OF ALGERIA (AIN OUSSERA)

This work has focused on the search for Cryptosporidium sp. carried out on a sample of 1 605 animals (1 235 lambs, 300 ewes, and 70 rams) from sixty-two flocks distributed in the commune of Ain Oussera one of the steppe regions of Algeria between 2014-2016., fifty-two flocks were positive for Cryptosporidium sp screening, with a flock prevalence 84% (CI95 % 72,8 % - 91  %).The total individual prevalence was 14.6%, the prevalence of lamb infestation was 15,4 %, for ewes and rams were 13,7 %, 4,3 % respectively (p < 0,05)

Rickettsial pathogen inhibits tick cell death through tryptophan metabolite mediated activation of p38 MAP kinase

Summary: Anaplasma phagocytophilum modulates various cell signaling pathways in mammalian cells for its survival. In this study, we report that A. phagocytophilum modulates tick tryptophan pathway to activate arthropod p38 MAP kinase for the survival of both this bacterium and its vector host. Increased level of tryptophan metabolite, xanthurenic acid (XA), was evident in A. phagocytophilum-infected ticks and tick cells. Lower levels of cell death markers and increased levels of total and phosphorylated p38 MAPK was noted in A. phagocytophilum-infected ticks and tick cells. Treatment with XA increased phosphorylated p38 MAPK levels and reduced cell death in A. phagocytophilum-infected tick cells. Furthermore, treatment with p38 MAPK inhibitor affected bacterial replication, decreased phosphorylated p38 MAPK levels and increased tick cell death. However, XA reversed these effects. Taken together, we provide evidence that rickettsial pathogen modulates arthropod tryptophan and p38 MAPK pathways to inhibit cell death for its survival in ticks

Anaphylatoxin signaling activates macrophages to control intracellular Rickettsia proliferation

Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund.Pathogenic Rickettsia species proliferate within the cytoplasm of permissive host cells in vivo. The cytoplasm of these host cells is adequate to support the complex metabolic and physiological needs for Rickettsia growth. However, a dramatic host/pathogen interplay occurs when Rickettsia encounter innate immune cells, whereby the bacteria can proliferate as normal or the host can restrict bacterial growth. This interplay is most divergent within myeloid host cells, where intra- and extracellular factors can produce either successful Rickettsia parasitism or innate immune control of bacterial proliferation. With the prior knowledge that the mammalian complement system is activated during mammalian infection, we sought to determine if extracellular complement activation and anaphylatoxin signaling can modify the fate of Rickettsia within mononuclear host cells. Results indicate that supplementation of growth media with either C3a or C5a anaphylatoxin peptides is sufficient for many myeloid cells to control the proliferation of multiple different Rickettsia species. Chemical or genetic disruption of anaphylatoxin signaling or anaphylatoxin receptors eliminates complement-induced restriction of bacterial proliferation. Finally, anaphylatoxin signaling modifies macrophage physiology by inducing inflammatory phenotypes that ultimately control the intracellular proliferation of these pathogens.https://doi.org/10.1128/spectrum.02538-2

Molecular investigation and phylogeny of Anaplasmataceae species infecting domestic animals and ticks in Corsica, France

Abstract Backgrounds Corsica is a French island situated in the Mediterranean Sea. The island provides suitable natural conditions to study disease ecology, especially tick-borne diseases and emerging diseases in animals and ticks. The family Anaplasmataceae is a member of the order Rickettsiales; it includes the genera Anaplasma, Ehrlichia, Neorickettsia and Wolbachia. Anaplasmosis and ehrlichiosis traditionally refer to diseases caused by obligate intracellular bacteria of the genera Anaplasma and Ehrlichia. The aim of this study was to identify and estimate the prevalence of Anaplasmataceae species infecting domestic animals and ticks in Corsica. Methods In this study, 458 blood samples from sheep, cattle, horses, goats, dogs, and 123 ticks removed from cattle, were collected in Corsica. Quantitative real-time PCR screening and genetic characterisation of Anaplasmataceae bacteria were based on the 23S rRNA, rpoB and groEl genes. Results Two tick species were collected in the present study: Rhipicephalus bursa (118) and Hyalomma marginatum marginatum (5). Molecular investigation showed that 32.1% (147/458) of blood samples were positive for Anaplasmataceae infection. Anaplasma ovis was identified in 42.3% (93/220) of sheep. Anaplasma marginale was amplified from 100% (12/12) of cattle and two R. bursa (2/123). Several potentially new species were also identified: Anaplasma cf. ovis, “Candidatus Anaplasma corsicanum”, “Candidatus Anaplasma mediterraneum” were amplified from 17.3% (38/220) of sheep, and Anaplasma sp. marginale-like was amplified from 80% (4/5) of goats. Finally, one R. bursa tick was found to harbour the DNA of E. canis. All samples from horses and dogs were negative for Anaplasmataceae infection. Conclusions To our knowledge, this study is the first epidemiological survey on Anaplasmataceae species infecting animals and ticks in Corsica and contributes toward the identification of current Anaplasmataceae species circulating in Corsica

Natural Anaplasmataceae infection in Rhipicephalus bursa ticks collected ă from sheep in the French Basque Country

International audienceRhipicephalus bursa is one of 79 species of the genus Rhipicephalus in ă the family of Ixodidae. In this study, we investigated Anaplasmataceae ă bacteria associated with R. bursa collected after an epizootic outbreak ă of ovine anaplasmosis. 76 adult ticks, (60 male and 16 female ticks), ă were removed from sheep in two farms and all identified as R. bursa, all ă females were partially engorged. We found that 50% of the ticks were ă positive in the initial Anaplasmataceae qPCR screening. Bacterial ă species was identified by analyzing the sequences of amplicons of 23S ă rRNA, groEL and rpoB genes. 22.4% of ticks contained DNA of Anaplasma ă phagocytophilum and 7.9% the DNA of Anaplasma ovis. Based on 23S rRNA ă and groEL genes analysis, we found that 19.7% of ticks contained a ă potentially new species of Ehrlichia. We propose the status of ă Candidatus for this uncultured species and we provisionally name it ă Candidatus Ehrlichia urmitei. No Wolbachia were identified. These ă results show that R. bursa can be a carrier of Anaplasmataceae bacteria. ă (C) 2016 Elsevier GmbH. All rights reserved

Bartonella bovis and Candidatus Bartonella davousti in cattle from Senegal

International audienceIn Senegal, domestic ruminants play a vital role in the economy and agriculture and as a food source for people. Bartonellosis in animals is a neglected disease in the tropical regions, and little information is available about the occurrence of this disease in African ruminants. Human bartonellosis due to Bartonella quintana has been previously reported in Senegal. In this study, 199 domestic ruminants, including 104 cattle, 43 sheep, and 52 goats were sampled in villages from the Senegalese regions of Sine Saloum and Casamance. We isolated 29 Bartonella strains, all exclusively from cattle. Molecular and genetic characterization of isolated strains identified 27 strains as Bartonella bovis and two strains as potentially new species. The strains described here represent the first Bartonella strains isolated from domestic ruminants in Senegal and the first putative new Bartonella sp. isolated from cattle in Africa. (C) 2016 Elsevier Ltd. All rights reserved