Rickettsia are a group of intracellular bacteria that can infect horses, among other animals. These bacteria are primarily transmitted through arthropod vectors such as ticks. In horses, Rickettsial infections may lead to a range of clinical signs, often associated with fever, lethargy, and other systemic symptoms. The detection and diagnosis of Rickettsial infections in horses typically involve serological tests and molecular techniques to identify the presence of the bacteria. This topic includes a collection of peer-reviewed research studies and scholarly articles that explore the epidemiology, pathogenesis, diagnostic methods, and potential treatment strategies for Rickettsial infections in equine populations.
Aleman M, Vedavally U, Pusterla N, Wensley F, Berryhill E, Madigan JE.Comprehensive descriptions of equids with granulocytic anaplasmosis (EGA) with neurologic or muscle disease and other atypical presentations are scarce in the literature. Objective: Describe the clinical signs, laboratory findings, treatment, and outcome of equids with EGA with emphasis on neurologic and muscle disease. Methods: Thirty-eight horses, 1 donkey. Methods: Retrospective study. Equids with EGA were included. The electronic data base was searched from January 2000 to December 2022 using the words anaplasmosis, ehrlichiosis, granulocytic, and rickettsia. Signalment and clinical data w...
Muniz APM, Tolesano-Pascoli G, Vieira RBK, Polli MG, Rodrigues VDS, Gonzaga HT, Mamede CCN, Da Cunha NC, Szabó MJP, Yokosawa J.Rickettsia rickettsii is the etiological agent of Rocky Mountain spotted fever, which is an important tick-borne zoonosis and, in Brazil, it causes Brazilian spotted fever, which has high lethality rate. This study aimed to evaluate a synthetic peptide corresponding to a segment of the outer membrane protein A (OmpA) as an antigen in a serological test for the diagnosis of rickettsial infections. The amino acid sequence of the peptide was selected by predicting B cell epitopes using B Cell Epitope Prediction (Immune Epitope Database and Analysis Resource) and Epitopia and OmpA sequences of Ric...
Martínez Díaz HC, Gil-Mora J, Betancourt-Ruiz P, Silva-Ramos CR, Matiz-González JM, Villalba-Perez MA, Ospina-Pinto MC, Ramirez-Hernández A....Some hard ticks' species can act as vectors of a wide variety of pathogens of human and animal importance such as Anaplasma, Ehrlichia and Rickettsia spp. In Colombia, a total of forty-six tick species have been described, and some of them have been implicated as vectors of some infectious agents. The department of Cauca is one of the thirty-two departments of Colombia. Most of its population lives in rural areas and depends on agriculture as the main economic activity, favoring exposure to ticks and tick-borne pathogens. Thus, the present study aimed to determine the tick species and tick-bor...
Chang QC, Hu Y, Wu TT, Ma XX, Jiang BG, Jia N, Wang AQ, Jiang JF. is a tick-borne pathogen that infects humans; however, the vertebrate hosts of this pathogen have not been clearly defined. Our molecular examination of spp. infecting mammals and ticks in China, identified the A, A, and 17KD gene sequences of in horses and their ticks. This indicates a role of horses in epidemiology.
Zhang Y, Wen X, Xiao P, Fan X, Li M, Chahan B.Ticks in Xinjiang distribute widely and account for one third of China. Ticks can carry and transmit bacteria, virus, and parasite. However, the research of tick-borne pathogens in Xinjiang is rather little. To understand the situation of hard tick carry Theileria equi, Babesia caballi and Rickettsia spp. of Zhaosu and Altay in Xinjiang. In this study, 119 tick samples were obtained from horses in Xinjiang, China, Ticks were identified morphologically to determine species and PCR was used to investigate the situation of pathogens by hard ticks. One hundred and seven belong to Dermacentor margi...
Ali A, Zahid H, Zeb I, Tufail M, Khan S, Haroon M, Tufail M, Bilal M, Hussain M, Alouffi AS, Muñoz-Leal S, Labruna MB.Studies on ticks infesting equids are lacking in various parts of the world, including Khyber Pakhtunkhwa (KP), Pakistan. The aim of this study was to investigate the diversity of ticks infesting equids, associated risk factors and rickettsial detection in ticks from equids in KP. Methods: Inspection of 404 equid hosts from November 2018 to October 2019 resulted in the collection of 550 ticks. Data on tick-associated risk factors were collected from equid owners by means of a questionnaire. After morphological identification, partial DNA sequences of the tick mitochondrial 16S rRNA gene were u...
Bermúdez C S, Zaldívar Y, Domínguez A L, Hernández M, de Antinori MEB, Krawczak FS.Rickettsia amblyommatis is widely distributed in the Americas, and has been reported to infect different species of ticks within its distribution. In Panama, R. amblyommatis is the most common Rickettsia and its presence was molecularly detected in nine species of ticks and one flea species. This work described the isolation of R. amblyommatis in Vero cells by shell vial technique, from Amblyomma mixtum ticks collected from a captive tapir from Gamboa (Colon province), and a horse from El Valle de Antón (Cocle province). These represent the first isolations of R. amblyommatis in Panama.
Rivera-Páez FA, Martins TF, Ossa-López PA, Sampieri BR, Camargo-Mathias MI.Rickettsiosis are emerging or re-emerging diseases, with a worldwide distribution associated to transmission by arthropod vectors. Rickettsia species belong to the spotted fever group (SFG) and are transmitted by hard ticks (Acari: Ixodidae) that may act as vectors and reservoirs. This study carried out a molecular detection of Rickettsia from 7 species of the family Ixodidae collected from domestic hosts by PCR amplification of fragments of the citrate synthase "gltA" gene and outer membrane protein "ompA" gene. Of the 204 samples analyzed, 11.3% (23) were positive for rickettsial infection. ...
Vieira FT, Acosta ICL, Martins TF, Filho JM, Krawczak FDS, Barbieri ARM, Egert L, Fernandes DR, Braga FR, Labruna MB, Dietze R.This work aims to identify and quantify the percentage of Rickettsia spp., Ehrlichia spp., Babesia spp. and Hepatozoon spp. positive pet dogs, and to identify ticks collected on these animals in the state of Espírito Santo, in the Southeast region of Brazil. The study included 378 dogs, 226 females and 152 males, of various breeds and ages (mean age of 4.1 years). All animals were examined for ticks, and whole blood was collected and processed by conventional PCR protocols for Babesia spp., Anaplasmataceae, Hepatozoon spp. and by real-time PCR for Ehrlichia canis. Of the 378 dogs examined, 15...
Almeida RF, Garcia MV, Cunha RC, Matias J, Labruna MB, Andreotti R.Ticks are vectors of various pathogens, including Rickettsia spp., which are responsible for causing an emerging disease of global significance. In the present study, an epidemiological survey was performed to identify Rickettsia spp. of the spotted fever group (SFG) in ticks and wild hosts in a native forest adjacent to livestock farming activity. The ticks and blood were evaluated by a hemolymph test and by PCR using the primers CS78 and CS323, which target a partial sequence of the enzyme citrate synthase (gltA) gene. Positive samples by PCR were further tested with the primers Rr190.70p an...
Ybañez AP, Sato F, Nambo Y, Fukui T, Masuzawa T, Ohashi N, Matsumoto K, Kishimoto T, Inokuma H.A total of 87 Thoroughbred horses and 10 ixodid ticks from a ranch in Hidaka district, Hokkaido were tested for tick-borne diseases. Using the indirect fluorescent antibody (IFA) method, 3.4, 92.0 and 97.7% of the horses showed antibody titers of ≥ 80 against Anaplasma phagocytophilum, Rickettsia helvetica, and Borrelia garinii, respectively. This is the first report of infection with the 3 pathogens in horses in Japan. Using PCR, DNAs from the peripheral blood of all horses were found negative with any Anaplasma, Rickettsia and Borrelia spp., while those from Haemaphysalis megaspinosa ticks...
Batista FG, Silva DM, Green KT, Tezza LB, Vasconcelos SP, Carvalho SG, Silveira I, Moraes-Filho J, Labruna MB, Fortes FS, Molento MB.Brazilian Spotted Fever (BSF) is a lethal rickettsiosis in humans caused by the bacteria Rickettsia rickettsii, and is endemic in some areas of Brazil. Horses and dogs are part of the disease's life cycle and they may also serve as sentinel animals in epidemiological studies. The first human BSF case in the State of Paraná was reported in 2005. The present study was conducted in the municipality of Almirante Tamandaré, where no previous case of BSF was reported. Serum samples were collected from 71 horses and 20 dogs from nine properties in the area. Ticks were also collected from these anim...
Pacheco RC, Moraes-Filho J, Guedes E, Silveira I, Richtzenhain LJ, Leite RC, Labruna MB.The present study was performed in an area endemic for Brazilian spotted fever (BSF) in Juiz de Fora, state of Minas Gerais, Brazil, during the years 2007 and 2008, when fatal cases of BSF (caused by Rickettsia rickettsii) were reported. Adult ticks (Acari: Ixodidae) identified as Rhipicephalus sanguineus (Latreille) and Amblyomma cajennense (Fabricius) were collected from dogs and horses, respectively, and tested by polymerase chain reaction (PCR). Overall, 13.1% of the Rh. sanguineus ticks and none of the A. cajennense were found to be infected with R. rickettsii. Two isolates of R. ricketts...
Vianna MC, Horta MC, Sangioni LA, Cortez A, Soares RM, Mafra CL, Galvão MA, Labruna MB, Gennari SM.The present study investigated the infection by spotted fever rickettsia in an endemic area for Brazilian spotted fever (BSF; caused by Rickettsia rickettsii) in Minas Gerais State, Brazil. Human, canine and equine sera samples, and Amblyomma cajennense adult ticks collected in a rural area of Itabira City, Minas Gerais State were tested for rickettsial infection. Through Immunofluorescence Assay (IFA) we demonstrated the presence of antibodies anti-R. rickettsii in 8.2%, 81.3% and 100% of the human, canine and equine sera, respectively. None of the 356 tick specimens analyzed were positive fo...
Cardoso LD, Freitas RN, Mafra CL, Neves CV, Figueira FC, Labruna MB, Gennari SM, Walker DH, Galvão MA.The present study was intended to characterize Rickettsia spp. circulating in arthropod vectors in Caratinga, Minas Gerais, Brazil, by PCR and to investigate the presence of antibodies against the spotted fever Rickettsiae group (SFRG) in dogs and horses. 2,610 arthropods were collected and taxonomically identified. DNA samples obtained from these vectors were submitted to PCR and cycle-sequenced. Ctenocephalides and Amblyomma cajennense showed sequences presenting 100.0% homology with R. felis. A sequence obtained from Rhipicephalus sanguineus showed 99.0% homology with R. felis, and a sequen...
de la Fuente J, Ayoubi P, Blouin EF, Almazán C, Naranjo V, Kocan KM.Anaplasma phagocytophilum (Rickettsiales: Anaplasmataceae) causes human, equine and canine granulocytic anaplasmosis and tick-borne fever of ruminants. The rickettsia parasitizes granulocytes and bone marrow progenitor cells, and can be propagated in human promyelocytic and tick cell lines. In this study, microarrays of synthetic polynucleotides of 21,329 human genes were used to identify genes that are differentially expressed in HL-60 human promyelocytic cells in response to infection with A. phagocytophilum. Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) of selec...
Horta MC, Labruna MB, Sangioni LA, Vianna MC, Gennari SM, Galvão MA, Mafra CL, Vidotto O, Schumaker TT, Walker DH.In serum samples obtained from all the healthy humans, horses, dogs, and donkeys present on three farms in the Pedreira Municipality, an endemic area for Brazilian spotted fever, an indirect immunofluorescence assay (IFA) detected antibodies against Rickettsia rickettsii in 17 (77.3%) horses, 5 (31.3%) dogs (titers ranging from 64 to 4,048), and none of 4 donkeys or 50 humans. Five canine and eight equine sera with high antibody titers to R. rickettsii were also tested by IFA against R. bellii, R. akari, and R. africae antigens. Sera from two horses and two dogs that showed similar high antibo...
Ripoll CM, Remondegui CE, Ordonez G, Arazamendi R, Fusaro H, Hyman MJ, Paddock CD, Zaki SR, Olson JG, Santos-Buch CA.Between November 1993 and March 1994, a cluster 6 pediatric patients with acute febrile illnesses associated with rashes was identified in Jujuy Province, Argentina. Immunohistochemical staining of tissues confirmed spotted fever group rickettsial infection in a patient with fatal disease, and testing of serum of a patient convalescing from the illness by using an indirect immunofluorescence assay (IFA) demonstrated antibodies reactive with spotted fever group rickettsiae. A serosurvey was conducted among 16 households in proximity to the index case. Of 105 healthy subjects evaluated by IFA, 1...
Ripoll CM, Remondegui CE, Ordonez G, Arazamendi R, Fusaro H, Hyman MJ, Paddock CD, Zaki SR, Olson JG, Santos-Buch CA.Between November 1993 and March 1994, a cluster 6 pediatric patients with acute febrile illnesses associated with rashes was identified in Jujuy Province, Argentina. Immunohistochemical staining of tissues confirmed spotted fever group rickettsial infection in a patient with fatal disease, and testing of serum of a patient convalescing from the illness by using an indirect immunofluorescence assay (IFA) demonstrated antibodies reactive with spotted fever group rickettsiae. A serosurvey was conducted among 16 households in proximity to the index case. Of 105 healthy subjects evaluated by IFA, 1...
Horta MC, Labruna MB, Sangioni LA, Vianna MC, Gennari SM, Galvão MA, Mafra CL, Vidotto O, Schumaker TT, Walker DH.In serum samples obtained from all the healthy humans, horses, dogs, and donkeys present on three farms in the Pedreira Municipality, an endemic area for Brazilian spotted fever, an indirect immunofluorescence assay (IFA) detected antibodies against Rickettsia rickettsii in 17 (77.3%) horses, 5 (31.3%) dogs (titers ranging from 64 to 4,048), and none of 4 donkeys or 50 humans. Five canine and eight equine sera with high antibody titers to R. rickettsii were also tested by IFA against R. bellii, R. akari, and R. africae antigens. Sera from two horses and two dogs that showed similar high antibo...
Pacheco RC, Moraes-Filho J, Guedes E, Silveira I, Richtzenhain LJ, Leite RC, Labruna MB.The present study was performed in an area endemic for Brazilian spotted fever (BSF) in Juiz de Fora, state of Minas Gerais, Brazil, during the years 2007 and 2008, when fatal cases of BSF (caused by Rickettsia rickettsii) were reported. Adult ticks (Acari: Ixodidae) identified as Rhipicephalus sanguineus (Latreille) and Amblyomma cajennense (Fabricius) were collected from dogs and horses, respectively, and tested by polymerase chain reaction (PCR). Overall, 13.1% of the Rh. sanguineus ticks and none of the A. cajennense were found to be infected with R. rickettsii. Two isolates of R. ricketts...
Ali A, Zahid H, Zeb I, Tufail M, Khan S, Haroon M, Tufail M, Bilal M, Hussain M, Alouffi AS, Muñoz-Leal S, Labruna MB.Studies on ticks infesting equids are lacking in various parts of the world, including Khyber Pakhtunkhwa (KP), Pakistan. The aim of this study was to investigate the diversity of ticks infesting equids, associated risk factors and rickettsial detection in ticks from equids in KP. Methods: Inspection of 404 equid hosts from November 2018 to October 2019 resulted in the collection of 550 ticks. Data on tick-associated risk factors were collected from equid owners by means of a questionnaire. After morphological identification, partial DNA sequences of the tick mitochondrial 16S rRNA gene were u...
Vieira FT, Acosta ICL, Martins TF, Filho JM, Krawczak FDS, Barbieri ARM, Egert L, Fernandes DR, Braga FR, Labruna MB, Dietze R.This work aims to identify and quantify the percentage of Rickettsia spp., Ehrlichia spp., Babesia spp. and Hepatozoon spp. positive pet dogs, and to identify ticks collected on these animals in the state of Espírito Santo, in the Southeast region of Brazil. The study included 378 dogs, 226 females and 152 males, of various breeds and ages (mean age of 4.1 years). All animals were examined for ticks, and whole blood was collected and processed by conventional PCR protocols for Babesia spp., Anaplasmataceae, Hepatozoon spp. and by real-time PCR for Ehrlichia canis. Of the 378 dogs examined, 15...
Cardoso LD, Freitas RN, Mafra CL, Neves CV, Figueira FC, Labruna MB, Gennari SM, Walker DH, Galvão MA.The present study was intended to characterize Rickettsia spp. circulating in arthropod vectors in Caratinga, Minas Gerais, Brazil, by PCR and to investigate the presence of antibodies against the spotted fever Rickettsiae group (SFRG) in dogs and horses. 2,610 arthropods were collected and taxonomically identified. DNA samples obtained from these vectors were submitted to PCR and cycle-sequenced. Ctenocephalides and Amblyomma cajennense showed sequences presenting 100.0% homology with R. felis. A sequence obtained from Rhipicephalus sanguineus showed 99.0% homology with R. felis, and a sequen...
Vianna MC, Horta MC, Sangioni LA, Cortez A, Soares RM, Mafra CL, Galvão MA, Labruna MB, Gennari SM.The present study investigated the infection by spotted fever rickettsia in an endemic area for Brazilian spotted fever (BSF; caused by Rickettsia rickettsii) in Minas Gerais State, Brazil. Human, canine and equine sera samples, and Amblyomma cajennense adult ticks collected in a rural area of Itabira City, Minas Gerais State were tested for rickettsial infection. Through Immunofluorescence Assay (IFA) we demonstrated the presence of antibodies anti-R. rickettsii in 8.2%, 81.3% and 100% of the human, canine and equine sera, respectively. None of the 356 tick specimens analyzed were positive fo...
Batista FG, Silva DM, Green KT, Tezza LB, Vasconcelos SP, Carvalho SG, Silveira I, Moraes-Filho J, Labruna MB, Fortes FS, Molento MB.Brazilian Spotted Fever (BSF) is a lethal rickettsiosis in humans caused by the bacteria Rickettsia rickettsii, and is endemic in some areas of Brazil. Horses and dogs are part of the disease's life cycle and they may also serve as sentinel animals in epidemiological studies. The first human BSF case in the State of Paraná was reported in 2005. The present study was conducted in the municipality of Almirante Tamandaré, where no previous case of BSF was reported. Serum samples were collected from 71 horses and 20 dogs from nine properties in the area. Ticks were also collected from these anim...
Rivera-Páez FA, Martins TF, Ossa-López PA, Sampieri BR, Camargo-Mathias MI.Rickettsiosis are emerging or re-emerging diseases, with a worldwide distribution associated to transmission by arthropod vectors. Rickettsia species belong to the spotted fever group (SFG) and are transmitted by hard ticks (Acari: Ixodidae) that may act as vectors and reservoirs. This study carried out a molecular detection of Rickettsia from 7 species of the family Ixodidae collected from domestic hosts by PCR amplification of fragments of the citrate synthase "gltA" gene and outer membrane protein "ompA" gene. Of the 204 samples analyzed, 11.3% (23) were positive for rickettsial infection. ...
Almeida RF, Garcia MV, Cunha RC, Matias J, Labruna MB, Andreotti R.Ticks are vectors of various pathogens, including Rickettsia spp., which are responsible for causing an emerging disease of global significance. In the present study, an epidemiological survey was performed to identify Rickettsia spp. of the spotted fever group (SFG) in ticks and wild hosts in a native forest adjacent to livestock farming activity. The ticks and blood were evaluated by a hemolymph test and by PCR using the primers CS78 and CS323, which target a partial sequence of the enzyme citrate synthase (gltA) gene. Positive samples by PCR were further tested with the primers Rr190.70p an...
Bermúdez C S, Zaldívar Y, Domínguez A L, Hernández M, de Antinori MEB, Krawczak FS.Rickettsia amblyommatis is widely distributed in the Americas, and has been reported to infect different species of ticks within its distribution. In Panama, R. amblyommatis is the most common Rickettsia and its presence was molecularly detected in nine species of ticks and one flea species. This work described the isolation of R. amblyommatis in Vero cells by shell vial technique, from Amblyomma mixtum ticks collected from a captive tapir from Gamboa (Colon province), and a horse from El Valle de Antón (Cocle province). These represent the first isolations of R. amblyommatis in Panama.
Chang QC, Hu Y, Wu TT, Ma XX, Jiang BG, Jia N, Wang AQ, Jiang JF. is a tick-borne pathogen that infects humans; however, the vertebrate hosts of this pathogen have not been clearly defined. Our molecular examination of spp. infecting mammals and ticks in China, identified the A, A, and 17KD gene sequences of in horses and their ticks. This indicates a role of horses in epidemiology.
de la Fuente J, Ayoubi P, Blouin EF, Almazán C, Naranjo V, Kocan KM.Anaplasma phagocytophilum (Rickettsiales: Anaplasmataceae) causes human, equine and canine granulocytic anaplasmosis and tick-borne fever of ruminants. The rickettsia parasitizes granulocytes and bone marrow progenitor cells, and can be propagated in human promyelocytic and tick cell lines. In this study, microarrays of synthetic polynucleotides of 21,329 human genes were used to identify genes that are differentially expressed in HL-60 human promyelocytic cells in response to infection with A. phagocytophilum. Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) of selec...
Martínez Díaz HC, Gil-Mora J, Betancourt-Ruiz P, Silva-Ramos CR, Matiz-González JM, Villalba-Perez MA, Ospina-Pinto MC, Ramirez-Hernández A....Some hard ticks' species can act as vectors of a wide variety of pathogens of human and animal importance such as Anaplasma, Ehrlichia and Rickettsia spp. In Colombia, a total of forty-six tick species have been described, and some of them have been implicated as vectors of some infectious agents. The department of Cauca is one of the thirty-two departments of Colombia. Most of its population lives in rural areas and depends on agriculture as the main economic activity, favoring exposure to ticks and tick-borne pathogens. Thus, the present study aimed to determine the tick species and tick-bor...
Ybañez AP, Sato F, Nambo Y, Fukui T, Masuzawa T, Ohashi N, Matsumoto K, Kishimoto T, Inokuma H.A total of 87 Thoroughbred horses and 10 ixodid ticks from a ranch in Hidaka district, Hokkaido were tested for tick-borne diseases. Using the indirect fluorescent antibody (IFA) method, 3.4, 92.0 and 97.7% of the horses showed antibody titers of ≥ 80 against Anaplasma phagocytophilum, Rickettsia helvetica, and Borrelia garinii, respectively. This is the first report of infection with the 3 pathogens in horses in Japan. Using PCR, DNAs from the peripheral blood of all horses were found negative with any Anaplasma, Rickettsia and Borrelia spp., while those from Haemaphysalis megaspinosa ticks...
Zhang Y, Wen X, Xiao P, Fan X, Li M, Chahan B.Ticks in Xinjiang distribute widely and account for one third of China. Ticks can carry and transmit bacteria, virus, and parasite. However, the research of tick-borne pathogens in Xinjiang is rather little. To understand the situation of hard tick carry Theileria equi, Babesia caballi and Rickettsia spp. of Zhaosu and Altay in Xinjiang. In this study, 119 tick samples were obtained from horses in Xinjiang, China, Ticks were identified morphologically to determine species and PCR was used to investigate the situation of pathogens by hard ticks. One hundred and seven belong to Dermacentor margi...
Muniz APM, Tolesano-Pascoli G, Vieira RBK, Polli MG, Rodrigues VDS, Gonzaga HT, Mamede CCN, Da Cunha NC, Szabó MJP, Yokosawa J.Rickettsia rickettsii is the etiological agent of Rocky Mountain spotted fever, which is an important tick-borne zoonosis and, in Brazil, it causes Brazilian spotted fever, which has high lethality rate. This study aimed to evaluate a synthetic peptide corresponding to a segment of the outer membrane protein A (OmpA) as an antigen in a serological test for the diagnosis of rickettsial infections. The amino acid sequence of the peptide was selected by predicting B cell epitopes using B Cell Epitope Prediction (Immune Epitope Database and Analysis Resource) and Epitopia and OmpA sequences of Ric...
Aleman M, Vedavally U, Pusterla N, Wensley F, Berryhill E, Madigan JE.Comprehensive descriptions of equids with granulocytic anaplasmosis (EGA) with neurologic or muscle disease and other atypical presentations are scarce in the literature. Objective: Describe the clinical signs, laboratory findings, treatment, and outcome of equids with EGA with emphasis on neurologic and muscle disease. Methods: Thirty-eight horses, 1 donkey. Methods: Retrospective study. Equids with EGA were included. The electronic data base was searched from January 2000 to December 2022 using the words anaplasmosis, ehrlichiosis, granulocytic, and rickettsia. Signalment and clinical data w...
