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Domenico Otranto - One of the best experts on this subject based on the ideXlab platform.
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Genetic characterization of Rhipicephalus sanguineus (sensu lato) ticks from dogs in Portugal
Parasites & vectors, 2017Co-Authors: Filipe Dantas-torres, Maria Stefania Latrofa, Giada Annoscia, Carla Maia, Luís Cardoso, Domenico OtrantoAbstract:Background The taxonomic status of the brown dog tick Rhipicephalus sanguineus (sensu stricto) is a subject of on-going debate; there is a consensus that populations of this tick species should be referred to as R. sanguineus (sensu lato) until its taxonomic status is resolved. Recent genetic studies revealed the existence of more than one lineage of R. sanguineus (s.l.) in temperate countries. In this study, we assessed the genetic identity of ticks collected from rural dogs living in several areas located in all major geographical regions of Portugal.
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Transcriptome of larvae representing the Rhipicephalus sanguineus complex.
Molecular and cellular probes, 2016Co-Authors: Leone De Marco, Filipe Dantas-torres, Domenico Otranto, Sara Epis, Francesco Comandatore, Daniele Porretta, Claudia Cafarchia, Valentina Mastrantonio, Sandra Urbanelli, Claudio BandiAbstract:Rhipicephalus sanguineus sensu lato (Ixodida: Ixodidae) is possibly the most widespread tick species worldwide, responsible for transmitting several vector-borne pathogens of medical and veterinary importance. Here, we explore the transcriptome of R. sanguineus s.l. larvae (Putignano strain). We sequenced total RNA from R. sanguineus s.l. larvae. A total of 15,566,986 short paired-end reads were de novo-assembled into 33,396 transcripts and then annotated and analyzed. Particular attention was paid to transcripts putatively encoding ATP-binding proteins, due to their importance as mechanisms of detoxification and acaricide resistance. Additionally, microsatellite loci were investigated, as these are useful markers for population genetic studies. The present data and analyses provide a comprehensive transcriptomic resource for R. sanguineus. The results presented here will aid further genetic and genomic studies of this important tick species.
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Molecular detection of tick-borne pathogens in Rhipicephalus sanguineus group ticks.
Ticks and tick-borne diseases, 2014Co-Authors: Maria Stefania Latrofa, Filipe Dantas-torres, Alessio Giannelli, Domenico OtrantoAbstract:a b s t r a c t The Rhipicephalus sanguineus group includes some of the most widespread dog ticks, whose identifica- tion currently represents a difficult task due to the morphological similarities of these ixodid species. Recently, following the morphological and molecular characterization of tick specimens collected from dogs in all continents, Rhipicephalus sanguineus sensu lato (s.l.), Rhipicephalus turanicus and three different operational taxonomic units (namely Rhipicephalus sp. I-III) have been identified. Therefore, a compre- hensive molecular study has been herein carried out to detect selected canine vector-borne pathogens (i.e., Anaplasma platys, Cercopithifilaria spp., Ehrlichia canis and Hepatozoon canis) in ticks belonging to the R. sanguineus group. A total of 204 tick specimens from dogs were examined and identified as R. sanguineus s.l. (n = 81), R. turanicus (n = 17), Rhipicephalus sp. I (n = 66), Rhipicephalus sp. II (n = 37), and Rhipicephalus sp. III (n = 3). PCR assays were performed to detect mitochondrial and ribosomal target genes of Cercop- ithifilaria spp., A. platys, E. canis and H. canis. Out of 204 specimens examined, 2.5%, 7.4% and 21.6% scored positive to A. platys, H. canis and Cercopithifilaria spp., respectively. In addition, co-infections with two pathogens (i.e., Cercopithifilaria bainae and A. platys or H. canis) were detected in four tick specimens. This study suggests a relationship between ticks belonging to the R. sanguineus group and the geographical distribution of A. platys, H. canis and Cercopithifilaria spp. However, the role of each representative tick species within the R. sanguineus group in the transmission of these canine pathogens needs to be further investigated.
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The enigma of the dog mummy from ancient Egypt and the origin of 'Rhipicephalus sanguineus'.
Parasites & vectors, 2014Co-Authors: Domenico Otranto, Alessio Giannelli, Jean-bernard Huchet, Cécile Callou, Filipe Dantas-torresAbstract:Background: Ticks belonging to the Rhipicephalus sanguineus group are amongst the most important vectors of pathogenic microorganisms to dogs and humans. However, the taxonomy of this species group is still the subject of debate, especially because there is no type specimen or reliable morphological description for Rhipicephalus sanguineus sensu stricto. Recently, a comprehensive morphological and genetic study on representative tick specimens from Europe, Africa, Americas, and Oceania, revealed the existence of at least four morphologically and genetically distinct species under the name ‘R. sanguineus’ infesting dogs from different countries. Methods: Herein, we examined morphologically tick specimens retrieved on a dog mummy from Ancient Egypt (ca. 1 st century – 4 th century A.D.). The dog mummy and associated ticks were found during an archaeological expedition conducted in El Deir. Results: Scanning electron micrographs allowed us to assess their identity as belonging to the R. sanguineus group. In addition on the basis of the scutal punctation pattern, spiracular plates, width of dorsal tail of spiracular plates relative to the adjacent festoon, female genital aperture, male adanal plates and accessory shields, these ticks were tentatively identified as Rhipicephalus sp. II (=temperate species). Conclusions: It can be concluded that R. sanguineus group ticks have infested dogs living in the Mediterranean region since ancient times. This finding represents the oldest record of ticks on any animal species and adds a new piece in the complex puzzle regarding tick parasitism on dogs and humans and their role as vectors of pathogens.
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Morphological and genetic diversity of Rhipicephalus sanguineus sensu lato from the New and Old Worlds
Parasites & vectors, 2013Co-Authors: Filipe Dantas-torres, Maria Stefania Latrofa, Giada Annoscia, Alessio Giannelli, Antonio Parisi, Domenico OtrantoAbstract:Background The taxonomic status of the brown dog tick (Rhipicephalus sanguineus sensu stricto), which has long been regarded as the most widespread tick worldwide and a vector of many pathogens to dogs and humans, is currently under dispute.
Filipe Dantas-torres - One of the best experts on this subject based on the ideXlab platform.
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Genetic characterization of Rhipicephalus sanguineus (sensu lato) ticks from dogs in Portugal
Parasites & vectors, 2017Co-Authors: Filipe Dantas-torres, Maria Stefania Latrofa, Giada Annoscia, Carla Maia, Luís Cardoso, Domenico OtrantoAbstract:Background The taxonomic status of the brown dog tick Rhipicephalus sanguineus (sensu stricto) is a subject of on-going debate; there is a consensus that populations of this tick species should be referred to as R. sanguineus (sensu lato) until its taxonomic status is resolved. Recent genetic studies revealed the existence of more than one lineage of R. sanguineus (s.l.) in temperate countries. In this study, we assessed the genetic identity of ticks collected from rural dogs living in several areas located in all major geographical regions of Portugal.
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Transcriptome of larvae representing the Rhipicephalus sanguineus complex.
Molecular and cellular probes, 2016Co-Authors: Leone De Marco, Filipe Dantas-torres, Domenico Otranto, Sara Epis, Francesco Comandatore, Daniele Porretta, Claudia Cafarchia, Valentina Mastrantonio, Sandra Urbanelli, Claudio BandiAbstract:Rhipicephalus sanguineus sensu lato (Ixodida: Ixodidae) is possibly the most widespread tick species worldwide, responsible for transmitting several vector-borne pathogens of medical and veterinary importance. Here, we explore the transcriptome of R. sanguineus s.l. larvae (Putignano strain). We sequenced total RNA from R. sanguineus s.l. larvae. A total of 15,566,986 short paired-end reads were de novo-assembled into 33,396 transcripts and then annotated and analyzed. Particular attention was paid to transcripts putatively encoding ATP-binding proteins, due to their importance as mechanisms of detoxification and acaricide resistance. Additionally, microsatellite loci were investigated, as these are useful markers for population genetic studies. The present data and analyses provide a comprehensive transcriptomic resource for R. sanguineus. The results presented here will aid further genetic and genomic studies of this important tick species.
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Molecular detection of tick-borne pathogens in Rhipicephalus sanguineus group ticks.
Ticks and tick-borne diseases, 2014Co-Authors: Maria Stefania Latrofa, Filipe Dantas-torres, Alessio Giannelli, Domenico OtrantoAbstract:a b s t r a c t The Rhipicephalus sanguineus group includes some of the most widespread dog ticks, whose identifica- tion currently represents a difficult task due to the morphological similarities of these ixodid species. Recently, following the morphological and molecular characterization of tick specimens collected from dogs in all continents, Rhipicephalus sanguineus sensu lato (s.l.), Rhipicephalus turanicus and three different operational taxonomic units (namely Rhipicephalus sp. I-III) have been identified. Therefore, a compre- hensive molecular study has been herein carried out to detect selected canine vector-borne pathogens (i.e., Anaplasma platys, Cercopithifilaria spp., Ehrlichia canis and Hepatozoon canis) in ticks belonging to the R. sanguineus group. A total of 204 tick specimens from dogs were examined and identified as R. sanguineus s.l. (n = 81), R. turanicus (n = 17), Rhipicephalus sp. I (n = 66), Rhipicephalus sp. II (n = 37), and Rhipicephalus sp. III (n = 3). PCR assays were performed to detect mitochondrial and ribosomal target genes of Cercop- ithifilaria spp., A. platys, E. canis and H. canis. Out of 204 specimens examined, 2.5%, 7.4% and 21.6% scored positive to A. platys, H. canis and Cercopithifilaria spp., respectively. In addition, co-infections with two pathogens (i.e., Cercopithifilaria bainae and A. platys or H. canis) were detected in four tick specimens. This study suggests a relationship between ticks belonging to the R. sanguineus group and the geographical distribution of A. platys, H. canis and Cercopithifilaria spp. However, the role of each representative tick species within the R. sanguineus group in the transmission of these canine pathogens needs to be further investigated.
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The enigma of the dog mummy from ancient Egypt and the origin of 'Rhipicephalus sanguineus'.
Parasites & vectors, 2014Co-Authors: Domenico Otranto, Alessio Giannelli, Jean-bernard Huchet, Cécile Callou, Filipe Dantas-torresAbstract:Background: Ticks belonging to the Rhipicephalus sanguineus group are amongst the most important vectors of pathogenic microorganisms to dogs and humans. However, the taxonomy of this species group is still the subject of debate, especially because there is no type specimen or reliable morphological description for Rhipicephalus sanguineus sensu stricto. Recently, a comprehensive morphological and genetic study on representative tick specimens from Europe, Africa, Americas, and Oceania, revealed the existence of at least four morphologically and genetically distinct species under the name ‘R. sanguineus’ infesting dogs from different countries. Methods: Herein, we examined morphologically tick specimens retrieved on a dog mummy from Ancient Egypt (ca. 1 st century – 4 th century A.D.). The dog mummy and associated ticks were found during an archaeological expedition conducted in El Deir. Results: Scanning electron micrographs allowed us to assess their identity as belonging to the R. sanguineus group. In addition on the basis of the scutal punctation pattern, spiracular plates, width of dorsal tail of spiracular plates relative to the adjacent festoon, female genital aperture, male adanal plates and accessory shields, these ticks were tentatively identified as Rhipicephalus sp. II (=temperate species). Conclusions: It can be concluded that R. sanguineus group ticks have infested dogs living in the Mediterranean region since ancient times. This finding represents the oldest record of ticks on any animal species and adds a new piece in the complex puzzle regarding tick parasitism on dogs and humans and their role as vectors of pathogens.
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Morphological and genetic diversity of Rhipicephalus sanguineus sensu lato from the New and Old Worlds
Parasites & vectors, 2013Co-Authors: Filipe Dantas-torres, Maria Stefania Latrofa, Giada Annoscia, Alessio Giannelli, Antonio Parisi, Domenico OtrantoAbstract:Background The taxonomic status of the brown dog tick (Rhipicephalus sanguineus sensu stricto), which has long been regarded as the most widespread tick worldwide and a vector of many pathogens to dogs and humans, is currently under dispute.
Maria Stefania Latrofa - One of the best experts on this subject based on the ideXlab platform.
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Genetic characterization of Rhipicephalus sanguineus (sensu lato) ticks from dogs in Portugal
Parasites & vectors, 2017Co-Authors: Filipe Dantas-torres, Maria Stefania Latrofa, Giada Annoscia, Carla Maia, Luís Cardoso, Domenico OtrantoAbstract:Background The taxonomic status of the brown dog tick Rhipicephalus sanguineus (sensu stricto) is a subject of on-going debate; there is a consensus that populations of this tick species should be referred to as R. sanguineus (sensu lato) until its taxonomic status is resolved. Recent genetic studies revealed the existence of more than one lineage of R. sanguineus (s.l.) in temperate countries. In this study, we assessed the genetic identity of ticks collected from rural dogs living in several areas located in all major geographical regions of Portugal.
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Molecular detection of tick-borne pathogens in Rhipicephalus sanguineus group ticks.
Ticks and tick-borne diseases, 2014Co-Authors: Maria Stefania Latrofa, Filipe Dantas-torres, Alessio Giannelli, Domenico OtrantoAbstract:a b s t r a c t The Rhipicephalus sanguineus group includes some of the most widespread dog ticks, whose identifica- tion currently represents a difficult task due to the morphological similarities of these ixodid species. Recently, following the morphological and molecular characterization of tick specimens collected from dogs in all continents, Rhipicephalus sanguineus sensu lato (s.l.), Rhipicephalus turanicus and three different operational taxonomic units (namely Rhipicephalus sp. I-III) have been identified. Therefore, a compre- hensive molecular study has been herein carried out to detect selected canine vector-borne pathogens (i.e., Anaplasma platys, Cercopithifilaria spp., Ehrlichia canis and Hepatozoon canis) in ticks belonging to the R. sanguineus group. A total of 204 tick specimens from dogs were examined and identified as R. sanguineus s.l. (n = 81), R. turanicus (n = 17), Rhipicephalus sp. I (n = 66), Rhipicephalus sp. II (n = 37), and Rhipicephalus sp. III (n = 3). PCR assays were performed to detect mitochondrial and ribosomal target genes of Cercop- ithifilaria spp., A. platys, E. canis and H. canis. Out of 204 specimens examined, 2.5%, 7.4% and 21.6% scored positive to A. platys, H. canis and Cercopithifilaria spp., respectively. In addition, co-infections with two pathogens (i.e., Cercopithifilaria bainae and A. platys or H. canis) were detected in four tick specimens. This study suggests a relationship between ticks belonging to the R. sanguineus group and the geographical distribution of A. platys, H. canis and Cercopithifilaria spp. However, the role of each representative tick species within the R. sanguineus group in the transmission of these canine pathogens needs to be further investigated.
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Morphological and genetic diversity of Rhipicephalus sanguineus sensu lato from the New and Old Worlds
Parasites & vectors, 2013Co-Authors: Filipe Dantas-torres, Maria Stefania Latrofa, Giada Annoscia, Alessio Giannelli, Antonio Parisi, Domenico OtrantoAbstract:Background The taxonomic status of the brown dog tick (Rhipicephalus sanguineus sensu stricto), which has long been regarded as the most widespread tick worldwide and a vector of many pathogens to dogs and humans, is currently under dispute.
Marcelo B. Labruna - One of the best experts on this subject based on the ideXlab platform.
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Successful Infection of Tick Cell Cultures of Rhipicephalus sanguineus (Tropical Lineage) with Ehrlichia canis.
Vector borne and zoonotic diseases (Larchmont N.Y.), 2018Co-Authors: Darci Moraes Barros-battesti, Marcelo B. Labruna, Rosangela Zacarias Machado, Marcos Rogério André, Keyla Carstens Marques De Sousa, Daniella Aparecida Franze, Leidiane Lima-duarte, Angelina Cirelli-moraes, Pablo Henrique Nunes, Jonas Moraes-filhoAbstract:Abstract There are two distinct lineages of ticks, Rhipicephalus sanguineus, in South America: tropical and temperate lineages. Only the tropical lineage is recognized as competent vector for Ehrli...
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“Candidatus Rickettsia asemboensis” in Rhipicephalus sanguineus ticks, Brazil
Acta tropica, 2016Co-Authors: Bruno Dall’agnol, Ugo Araújo Souza, Anelise Webster, Bárbara Weck, Barbara Stenzel, Marcelo B. Labruna, Guilherme Marcondes Klafke, João Ricardo Martins, Carlos A. Ferreira, José ReckAbstract:“Candidatus Rickettsia asemboensis” is an obligate intracellular bacterium of the Rickettsiales order, genetically related to species belonging to the Rickettsia felis group, agents of flea-borne spotted fever. Here we report for the first time the detection of “Ca. R. asemboensis”, a flea-associated organism, in Rhipicephalus sanguineus ticks. It is the first occurrence of this emerging bacterium in Brazil, which increases the geographical distribution of this R. felis-like agent.
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The taxonomic status of Rhipicephalus sanguineus (Latreille, 1806).
Veterinary parasitology, 2014Co-Authors: Santiago Nava, Agustín Estrada-peña, Marcelo B. Labruna, José M. Venzal, Trevor N. Petney, Lorenza Beati, Atilio J. Mangold, Matias P J Szabó, Mariano Mastropaolo, Alberto A. GuglielmoneAbstract:The brown dog tick, Rhipicephalus sanguineus sensu stricto, is a species with considerable public health and economic importance. However, the taxonomic status of this species is far from resolved. After more than 110 years of scientific work on R. sanguineus s.s., the situation is that there is no type, no solid description, nor is there a consensus about the range of morphological variability within the species. Recent findings based on laboratory crosses and molecular genetics strongly suggest that there are several entities grouped under the same name. Here we review the history of the taxon, and we point out the caveats behind any further work on this tick. The current taxonomic status of R. sanguineus s.s. thus lacks an informative original description, and is based on the existence of several morphological descriptions based on ticks originating from different populations, which show, in some cases, biological incompatibility and significant genetic divergence. We suggests that as a result it is not possible to assign the specific name R. sanguineus s.s. to any population. Further work is required based on the rules issued by the International Code of Zoological Nomenclature to clearly define the morphological range of the different populations.
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The taxonomic status of Rhipicephalus sanguineus
2014Co-Authors: Santiago Nava, Marcelo B. Labruna, José M. Venzal, Agustín Estrada-pe, Trevor N. Petney, Lorenza Beati, Atilio J. Mangold, Alberto A. GuglielmoneAbstract:a b s t r a c t The brown dog tick, Rhipicephalus sanguineus sensu stricto, is a species with considerable public health and economic importance. However, the taxonomic status of this species is far from resolved. After more than 110 years of scientific work on R. sanguineus s.s., the situation is that there is no type, no solid description, nor is there a consensus about the range of morphological variability within the species. Recent findings based on laboratory crosses and molecular genetics strongly suggest that there are several entities grouped under the same name. Here we review the history of the taxon, and we point out the caveats behind any further work on this tick. The current taxonomic status of R. sanguineus s.s. thus lacks an informative original description, and is based on the existence of several morphological descriptions based on ticks originating from different populations, which show, in some cases, biological incompatibility and significant genetic divergence. We suggests that as a result it is not possible to assign the specific name R. sanguineus s.s. to any population. Further work is required based on the rules issued by the International Code of Zoological
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Distribution of Rickettsia rickettsii in ovary cells of Rhipicephalus sanguineus (Latreille1806) (Acari: Ixodidae).
Parasites & vectors, 2011Co-Authors: Luís Flávio Da Silva Costa, Marcelo B. Labruna, Pablo Henrique Nunes, João Fábio Soares, Maria Izabel Camargo-mathiasAbstract:Background Considering the fact that the dog tick, Rhipicephalus sanguineus, has a great potential to become the vector of Brazilian Spotted Fever (BSF) for humans, the present study aimed to describe the distribution of the bacterium Rickettsia rickettsii, the etiological agent of BSF, in different regions of the ovaries of R. sanguineus using histological techniques. The ovaries were obtained from positive females confirmed by the hemolymph test and fed in the nymph stage on guinea pigs inoculated with R. rickettsii.
Michael L Levin - One of the best experts on this subject based on the ideXlab platform.
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Vector competence of Rhipicephalus sanguineus sensu stricto for Anaplasma platys.
Ticks and tick-borne diseases, 2020Co-Authors: Alyssa N Snellgrove, Inna Krapiunaya, Shelby L. Ford, Hannah M Stanley, Alexandra G. Wickson, Kris L. Hartzer, Michael L LevinAbstract:Abstract Anaplasma platys is a Gram-negative, obligate intracellular bacteria that causes canine infectious cyclic thrombocytopenia in dogs. The brown dog tick Rhipicephalus sanguineus sensu lato is presumed to be the vector of A. platys based on the overlap in distribution of R. sanguineus and A. platys infections, detection of A. platys DNA in both flat and engorged field-collected R. sanguineus, and the fact that dogs are primary hosts of both brown dog ticks and A. platys. However, the only study evaluating the vector competence of R. sanguineus for A. platys under controlled laboratory conditions reported an apparent inability of ticks to acquire or maintain the pathogen. In 2016, engorged female Rhipicephalus sanguineus sensu stricto ticks were collected off dogs to start a laboratory tick colony. After one generation of colony maintenance on tick-naive and pathogen-free New Zealand White rabbits, a rabbit used to feed F1 adults seroconverted to Anaplasma phagocytophilum antigen. PCR and subsequent DNA sequencing identified the presence of A. platys in both the adult ticks fed on this rabbit and their resulting F2 progenies. Retrospective testing of all previous (P and F1) life stages of this colony demonstrated that the infection originated from one field-collected A. platys-infected female whose progeny was propagated in the laboratory and produced the PCR-positive F1 adults. Over the following (F2-F4) generations, the prevalence of A. platys in this colony reached 90–100 % indicating highly efficient transovarial and horizontal transmission, as well as transstadial maintenance, of this pathogen by R. sanguineus s.s.
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Systematics and ecology of the brown dog tick, Rhipicephalus sanguineus
Ticks and tick-borne diseases, 2013Co-Authors: Jeremy S. Gray, Filipe Dantas-torres, Agustín Estrada-peña, Michael L LevinAbstract:Rhipicephalus sanguineus, the brown dog tick, kennel tick, or pan-tropical dog tick, is probably the most widespread ixodid tick, colonising both human and canine dwellings. It is of great significance in both human and veterinary medicine as a vector of several important pathogens and can also cause clinical illness in heavy infestations of dogs. However, there are still significant taxonomic uncertainties, and it is probable that some records of this tick refer to other species. Most past reviews have been broad-ranging or have focused on the pathogens that R. sanguineus transmits, and relatively few have considered its biology in detail or the issues around its true identity. The present review has paid most attention to the taxonomy of R. sanguineus and to the ecological factors that influence tick survival and distribution, particularly in a climate change context. It is evident that more research is required on the systematics of the R. sanguineus species complex, in order to elucidate the epidemiology and prevention of the diseases that it transmits, and to provide the relevant biological data required for development of predictive models of future tick distribution in a climate change scenario.
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effects of rickettsia conorii infection on the survival of Rhipicephalus sanguineus ticks
Clinical Microbiology and Infection, 2009Co-Authors: Michael L Levin, Lindsay F Killmaster, Marina E. Eremeeva, Gregory A. DaschAbstract:Rickettsia conorii conorii is the aetiologic agent of boutonneuse fever, also known as Mediterranean spotted fever or Marseilles fever in the Mediterranean area where it is endemic. The brown dog tick, Rhipicephalus sanguineus, is recognised as the principal vector of R. conorii [1,2]. Although a few experimental studies have suggested transovarial and transstadial transmission of R. conorii in Rh. sanguineus [3], there are practically no data available on the efficiency of such transmission or on this vector–pathogen interaction. One recent publication evaluated several methods for infecting Rh. sanguineus with R. conorii, but reported high mortality in infected ticks [4], which may have resulted from incompatibility between the particular rickettsial isolate and the source of ticks used, or from the manipulation itself. In an effort to establish a laboratory colony of Rh. sanguineus persistently infected with R. conorii for studying agent transmission, we assessed the effects of R. conorii infection on the survival of Rh. sanguineus larvae.
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An Outbreak of Rocky Mountain Spotted Fever Associated with a Novel Tick Vector, Rhipicephalus sanguineus, in Arizona, 2004
Annals of the New York Academy of Sciences, 2006Co-Authors: Linda J. Demma, Michael L Levin, Marina E. Eremeeva, Gregory A. Dasch, William L. Nicholson, Marc S. Traeger, Dianna M. Blau, Christopher D. Paddock, James E. Cheek, David L. SwerdlowAbstract:This study describes preliminary results of an investigation of RMSF in Arizona associated with the brown dog tick, Rhipicephalus sanguineus. High numbers of dogs and heavy infestations of ticks created a situation leading to human disease.