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Minervino AHH, Marcili A, Moraes-Filho J, Lima JTR, Soares HS, Malheiros AF, Dias SR, Gennari SM, Labruna MB. Molecular Detection of Tick-Borne Pathogens in Dogs from Indigenous Communities, Amazon, Brazil. Vector Borne Zoonotic Dis 2023; 23:458-464. [PMID: 37566524 DOI: 10.1089/vbz.2023.0014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/13/2023] Open
Abstract
Background: There are few reports of tick-borne pathogens infecting dogs living in indigenous communities of Brazil. Herein, we aimed to molecularly detect vector-borne pathogens in dogs from two indigenous communities in the Brazilian Amazon. Materials and Methods: We surveyed 327 dogs raised in Amazon region at 2 distinct indigenous ethnicities for the molecular detection of tick-borne pathogens (114 from Tapirapé and 213 from Karajá indigenous ethnicity). Whole blood samples were subjected to PCR and sequencing for Ehrlichia, Babesia, and Hepatozoon. Univariate and multivariate analyses were used to investigate the factors affecting the pathogen infection patterns in dogs. Results: Among the 327 blood samples, 40 were positive for Ehrlichia canis (12.2%), 2 for Anaplasma platys (0.61%), and 204 were positive for Hepatozoon canis (66.5%). Binary Logistic Regression showed association between E. canis infection and ethnicity (p = 0.010) and tick attachment (p = 0.041). Karajá dogs were 3.4 times (95% CI 1.3-8.5) more likely to be positive for E. canis than Tapirapé dogs. Dogs with ticks were 2.5 times more likely (95% CI 1.0-7.6) to be positive for E. canis than dogs without ticks. Conclusions: Our survey expands the knowledge regarding the presence of vector-borne pathogens in dogs from indigenous communities in the Amazon region.
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Affiliation(s)
| | - Arlei Marcili
- PhD Program in One Health, Santo Amaro University (UNISA), São Paulo, Brazil
| | - Jonas Moraes-Filho
- PhD Program in One Health, Santo Amaro University (UNISA), São Paulo, Brazil
| | - Julia T R Lima
- Faculty of Veterinary Medicine and Animal Science (FMVZ), University of São Paulo, São Paulo, Brazil
| | - Herbert S Soares
- PhD Program in One Health, Santo Amaro University (UNISA), São Paulo, Brazil
- Faculty of Veterinary Medicine and Animal Science (FMVZ), University of São Paulo, São Paulo, Brazil
| | - Antonio F Malheiros
- Faculty of Agricultural and Biological Sciences (FACAB), State University of Mato Grosso, Cáceres, Brazil
| | - Salatiel Ribeiro Dias
- Laboratory of Animal Health (LARSANA), Federal University of Western Pará (UFOPA), Santarém, Brazil
| | - Solange M Gennari
- PhD Program in One Health, Santo Amaro University (UNISA), São Paulo, Brazil
- Faculty of Veterinary Medicine and Animal Science (FMVZ), University of São Paulo, São Paulo, Brazil
| | - Marcelo B Labruna
- Faculty of Veterinary Medicine and Animal Science (FMVZ), University of São Paulo, São Paulo, Brazil
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Dantas-Torres F, Marzochi MCA, Muñoz-Leal S, Sales KGDS, Sousa-Paula LCD, Moraes-Filho J, Labruna MB. Ornithodoros cf. mimon infected with a spotted fever group Rickettsia in Brazil. Acta Trop 2022; 233:106541. [PMID: 35623399 DOI: 10.1016/j.actatropica.2022.106541] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 05/20/2022] [Accepted: 05/23/2022] [Indexed: 11/16/2022]
Abstract
Ornithodoros mimon is an argasid tick primarily associated with bats that also infest other animals including birds, opossums and humans. In this paper, we report the finding of an argasid species resembling O. mimon, which similarly may be found in human dwellings and parasitize humans in Brazil. We also provide molecular evidence that this argasid tick species may carry a rickettsial organism, whose pathogenicity remains unknown. A total of 16 ticks (two females, two males and 12 nymphs) were collected in the bedroom and in the attic of a human house, where cases of "insect" bites have been recurrent. These ticks were identified morphologically and genetically as Ornithodoros cf. mimon. Upon PCR testing, four of these ticks (one female and three nymphs) were positive for human blood and for a bacterium closely related to "Candidatus Rickettsia paranaensis". In conclusion, we report for the first time in Brazil an argasid tick species morphologically and genetically related to O. mimon, which feeds on humans and carry a rickettsial organism belonging to the spotted fever group. Further studies are needed to formally assess the taxonomic status of this tick species and also to investigate the pathogenicity of its associated rickettsial organism.
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Affiliation(s)
- Filipe Dantas-Torres
- Department of Immunology, Aggeu Magalhães Institute, Fundação Oswaldo Cruz (Fiocruz), Recife, Brazil.
| | - Mauro C A Marzochi
- Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Sebastián Muñoz-Leal
- Department of Animal Science, Faculty of Veterinary Sciences, University of Concepción, Chillán, Chile
| | | | | | - Jonas Moraes-Filho
- Mestrado e Doutorado em Saúde Única, Universidade Santo Amaro, São Paulo, Brazil
| | - Marcelo B Labruna
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine and Zootechny, University of São Paulo, São Paulo, Brazil
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Binder LC, Ramírez-Hernández A, Serpa MCDA, Moraes-Filho J, Pinter A, Scinachi CA, Labruna MB. Domestic dogs as amplifying hosts of Rickettsia rickettsii for Amblyomma aureolatum ticks. Ticks Tick Borne Dis 2021; 12:101824. [PMID: 34520994 DOI: 10.1016/j.ttbdis.2021.101824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 08/11/2021] [Accepted: 08/19/2021] [Indexed: 10/20/2022]
Abstract
Brazilian spotted fever (BSF) is an acute infectious disease caused by the bacterium Rickettsia rickettsii, which is transmitted by different tick species. Due to deleterious effects caused on ticks, the horizontal transmission of R. rickettsii through amplifying hosts is crucial for its maintenance in tick populations among BSF-endemic areas. The tick Amblyomma aureolatum is the main vector of R. rickettsii in the São Paulo metropolitan area; nevertheless, it is not known which vertebrate could act as an amplifying host for this tick species. Herein, we evaluated the potential of domestic dogs - primary hosts for A. aureolatum adults in BSF-endemic areas - to act as amplifying hosts. For this purpose, A. aureolatum non-infected adults were allowed to feed on two groups of dogs: the control group (G1), composed of one dog not exposed to R. rickettsii; and, the infected group (G2), composed of three dogs infected with R. rickettsii via tick parasitism. All G2-dogs became ill, seroconverted to R. rickettsii, and rickettsial DNA was detected in 87% of the engorged females that fed on them. Transovarial transmission rate was estimated to be 25% and infected larvae successfully transmitted R. rickettsii to guinea-pigs, confirming transovarial transmission and vector competence. No rickettsial DNA was detected in individual samples of eggs or larvae, which precluded the estimation of filial infection rate, but implies that it was low. Our results suggest that domestic dogs act as amplifying hosts of R. rickettsii for A. aureolatum ticks in BSF-endemic areas in Brazil.
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Affiliation(s)
- Lina C Binder
- Departamento de Medicina Veterinária Preventiva e Saúde animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil.
| | - Alejandro Ramírez-Hernández
- Departamento de Medicina Veterinária Preventiva e Saúde animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil; Grupo Parasitología Veterinaria, Universidad Nacional de Colombia, Bogotá D.C., Colombia
| | - Maria Carolina de Azevedo Serpa
- Departamento de Medicina Veterinária Preventiva e Saúde animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Jonas Moraes-Filho
- Mestrado em Medicina e Bem-estar Animal, Doutorado com ênfase em Saúde Única, Universidade Santo Amaro, São Paulo, SP, Brazil
| | - Adriano Pinter
- Superintendência de Controle de Endemias, São Paulo, SP, Brazil; Faculdade de Saúde Pública, Universidade de São Paulo, SP, Brazil
| | - Claudia A Scinachi
- Superintendência de Controle de Endemias, São Paulo, SP, Brazil; Faculdade de Saúde Pública, Universidade de São Paulo, SP, Brazil
| | - Marcelo B Labruna
- Departamento de Medicina Veterinária Preventiva e Saúde animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil
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Cortez A, Reis EAD, Gomes N, Souza-Filho AF, Gonçales AP, Pinto CM, Onofrio VC, Souza GO, Guedes IB, Lima DM, Carvalho TRVD, Moraes-Filho J, Heinemann MB. Leptospirose canina em uma população assintomática da região sudoeste do estado de São Paulo, Brasil. Braz J Vet Res Anim Sci 2020. [DOI: 10.11606/issn.1678-4456.bjvras.2020.167893] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A leptospirose é uma enfermidade infectocontagiosa que pode acometer os animais e o homem. Nos países tropicais e em desenvolvimento ocorrem 70% dos casos humanos, com mortalidade variando entre 10 a 70%. Os cães podem se tornar portadores assintomáticos por um longo período, podendo transmitir a Leptospira para humanos. Devido ao intenso convívio com o ser humano, os cães podem servir como sentinelas da contaminação ambiental. Esse trabalho investigou a frequência de ocorrência da leptospirose canina em populações assintomáticas da região sudoeste do estado de São Paulo. Para isso foram examinadas pela técnica de soroaglutinação microscópica (MAT), amostras de sangue provenientes de 572 cães assintomáticos dos municípios de Apiaí, Cananeia, Itapeva e Itu por amostragem de conveniência, oriundos de campanhas de castração. Em Apiaí, foram encontrados 40,5% dos animais reagentes para Leptospira spp.; em Itapeva, 42,6%; em Cananeia, 7,7% e em Itu, 5,1%. Os dados encontrados demonstram que, pelo menos, um animal dos municípios de Itapeva, Apiaí e Cananeia apresentaram título igual ou maior que 800, indicando a circulação da bactéria nessas localidades e que a equipe envolvida nas campanhas de castração precisam ser alertadas sobre o correto uso de equipamento de proteção individual, principalmente no esvaziamento mecânico da bexiga antes do procedimento cirúrgico. O estudo também sugere que as campanhas de castração podem ser estratégicas no monitoramento de doenças zoonóticas e poderiam auxiliar no estabelecimento de ações preventivas para a saúde humana e animal.
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Souza Z, Moraes B, Krawczak F, Zulzke L, Carvalho T, Sousa A, Agopian R, Marcili A, Labruna M, Moraes-Filho J. Detecção de anticorpos anti-Rickettsia rickettsii em cães residentes em área negligenciada no município de São Paulo, SP, Brasil. ARQ BRAS MED VET ZOO 2020. [DOI: 10.1590/1678-4162-11697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
RESUMO A febre maculosa brasileira (FMB), descrita inicialmente nos Estados Unidos como febre maculosa das Montanhas Rochosas, é uma antropozoonose relatada apenas no continente americano e causada pela bactéria Rickettsia rickettsii. No Brasil a transmissão ocorre sobretudo pela picada de carrapatos do gênero Amblyomma spp. A doença foi inicialmente descrita como de transmissão em áreas rurais e silvestres, no entanto áreas periurbanas e urbanas vêm apresentando casos, principalmente relacionados com a presença de humanos residindo em pequenos fragmentos de mata ciliar. O presente estudo teve por objetivo elucidar a dispersão da FMB nas proximidades dos reservatórios Guarapiranga e Billings, na cidade de São Paulo, SP. Para tanto, a presença de anticorpos anti-R. rickettsii, Rickettsia parkeri e Rickettsia bellii foi avaliada em cães atendidos nas campanhas de esterilização cirúrgica e residentes ao redor dos reservatórios. Foram coletadas amostras de 393 cães, e as amostras de soro foram analisadas pela reação de imunofluorescência indireta (RIFI), com ponto de corte de 1:64. Os títulos para R. rickettsii variaram de 256 a 4096, com positividade de 3,3% (13/393); para R. bellii, de 128 a 1024 e 4,1% (16/393) de positivos, e um único animal (0,25%) foi soropositivo para R. parkeri, com título de 128. Os achados permitem concluir que a região de estudo apresenta condições de se tornar uma possível área com casos de FMB, pois comporta fragmentação de Mata Atlântica, condições essas ideais para a manutenção do vetor do gênero Amblyomma já descrito na região, bem como para a presença da Rickettsia rickettsii circulante entre os cães, confirmada pela existência de anticorpos. Condutas referentes à conscientização da população por meio de trabalhos educacionais devem ser implantadas para a prevenção da doença na população da área.
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Affiliation(s)
| | - B.V. Moraes
- Universidade Santo Amaro, Brazil; Universidade de São Paulo, Brazil
| | | | | | | | | | | | - A. Marcili
- Universidade Santo Amaro, Brazil; Universidade de São Paulo, Brazil
| | | | - J. Moraes-Filho
- Universidade Santo Amaro, Brazil; Universidade de São Paulo, Brazil
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Ueno TEH, Cutolo AA, Martins TF, Moraes-Filho J, Azevedo SSD, Labruna MB. Rickettsial infection in equids, opossums and ticks in the municipality of Monte Mor, state of São Paulo, Brazil. ACTA ACUST UNITED AC 2020; 29:e015420. [PMID: 33237125 DOI: 10.1590/s1984-29612020073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 07/09/2020] [Indexed: 11/21/2022]
Abstract
The aim of this study was to investigate rickettsial infection in equids, opossums and ticks in the municipality of Monte Mor, a place where a Brazilian spotted fever case occurred in 2005. In addition, characteristics possibly associated with seropositivity in horses were analyzed. Serum samples from horses, mules and opossums (Didelphis albiventris) were subjected to indirect immunofluorescence assay (IFA) against Rickettsia rickettsii. The ticks collected from the animals were identified and Amblyomma sculptum ticks from the equids were tested using PCR for Rickettsia spp. Anti-R. rickettsii antibodies were detected in 22.6% (14/62) of the horses, none of the mules and 21.7% (5/23) of the opossums. Among the variables analyzed, only age > 12 years showed a statistically significant association with seropositivity among horses. All of the 166 A. sculptum ticks tested using PCR were negative. The results showed that rickettsiae of the spotted fever group was circulating in the municipality of Monte Mor when the samples were collected and indicate a need for surveillance of Brazilian spotted fever in this region.
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Affiliation(s)
- Tatiana Evelyn Hayama Ueno
- Polo Regional Alta Sorocabana, Agência Paulista de Tecnologia dos Agronegócios - APTA, Presidente Prudente, SP, Brasil
| | - André Antonio Cutolo
- Faculdade de Medicina Veterinária e Zootecnia, Universidade Estadual Paulista - UNESP, Botucatu, SP, Brasil
| | - Thiago Fernandes Martins
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | | | - Sérgio Santos de Azevedo
- Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande - UFCG, Patos, PB, Brasil
| | - Marcelo Bahia Labruna
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
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Fournier GFDSR, Pinter A, Muñoz-Leal S, Labruna MB, Lopes MG, Martins TF, Colácio L, Môra CRS, Moraes-Filho J, Dias RA. Implications of domestic dogs in the epidemiology of Rickettsia parkeri strain Atlantic rainforest and Rangelia vitalii in Southeastern Brazil. ACTA ACUST UNITED AC 2020; 29:e022419. [PMID: 32236336 DOI: 10.1590/s1984-29612020003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 12/16/2019] [Indexed: 11/22/2022]
Abstract
This study aimed to evaluate the occurrence of diseases transmitted by Amblyomma ovale in 61 dogs monitored for three years through collections of ticks and blood, interviews, telemetry and camera traps in three areas of Serra do Mar State Park, Brazil. Blood samples were used to investigate infection by Rangelia vitalii by real-time TaqMan PCR and Rickettsia parkeri by IIFA. The collected ticks were submitted to conventional PCR to investigate the presence of R. parkeri . These data were compared with the monitoring results and interviews with the owners. Dogs considered as companion presented a risk of infection by R. parkeri strain Mata Atlantica 5.4 times higher than those not considered as companion (p = 0.009). Dogs that had at least one A. ovale collected during the campaigns had a 10 times higher risk of infection by R. parkeri strain Mata Atlantica than those who did not (p = 0.009). One dog positive for R. vitalii by real-time TaqMan PCR was parasitized by A. ovale frequently during monitoring. Sequenced ompaA - positive DNA samples had 100% identity of R. parkeri strain Mata Atlantica clone As106. From the findings, it is urgent to control domestic dogs around rainforests to reduce zoonoses transmission.
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Affiliation(s)
- Gislene Fátima da Silva Rocha Fournier
- Centro de Inovação, Tecnologia e Educação - CITÉ, São José dos Campos, SP,Brasil.,Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Adriano Pinter
- Superintendência de Controle de Endemias de São Paulo, São Paulo, SP, Brasil
| | - Sebastian Muñoz-Leal
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Marcelo Bahia Labruna
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Marcos Gomes Lopes
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Thiago Fernandes Martins
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Luciana Colácio
- COLLIS Laboratório de Análise Clínica, Caraguatatuba, SP, Brasil
| | | | | | - Ricardo Augusto Dias
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
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Budweg CI, Sousa AOD, Carvalho TRVD, Souza ZÊS, Serpa MCDA, Martins TF, Nieri-Bastos F, Marcili A, Labruna MB, Moraes-Filho J. Serological survey of Rickettsia in equids from Vale do Paraíba, São Paulo, Brazil, and their tick identification and molecular investigation of Rickettsia. Braz J Vet Res Anim Sci 2019. [DOI: 10.11606/issn.1678-4456.bjvras.2019.158159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Brazilian spotted fever is a serious and lethal illness for humans and is caused by the Rickettsia rickettsii bacteria. In the state of São Paulo/SP (Brazil), the etiological agent of this disease is transmitted by the Amblyomma sculptum tick. It was already shown that horses infected with this bacteria produce a strong immune response and could be important sentinels for the detection of the disease in a proper region. The present investigation performed a serological survey in horses from five farms of Vale do Paraíba, São Paulo state, Brazil, searching for antibodies against, Rickettsia rickettsii, Rickettsia parkeri, Rickettsia amblyommatis, Rickettsia rhipicephali, and Rickettsia bellii. In each farm, ticks were also collected that were taxonomically identified and examined by real-time PCR for Rickettsia spp DNA. Blood samples were collected from 206 horses, and 334 ticks were picked up from these animals from January to December 2017. Eighty ticks wereA. sculptum and 254 Dermacentor nitens. Of the blood samples, 7.3% seroconverted to Rickettsia spp. Of these, 0.97% had a positive serological response to R. bellii. None of the 80 A. sculptum ticks were positive through real-time PCR for Rickettsia spp. Although there was no detection of ticks infected by Rickettsia spp in five farms of Paraíba Valley, the horses presented serological positive reactions against this agent. Thus, further large studies should be conducted in the area targeting hosts and vectors to generate data for control measures of the transmission of Brazilian spotted fever.
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Silva BRFD, Labruna MB, Marcili A, Santos CRD, Bastos BBB, Bordin JT, Moraes-Filho J. Rangelia vitalii infection in a dog from São Paulo city, Brazil: case report. Braz J Vet Res Anim Sci 2019. [DOI: 10.11606/issn.1678-4456.bjvras.2019.150791] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Canine rangeliosis is an extravascular hemolytic disease caused by the protozoan Rangelia vitalii, which is transmitted by ticks of the species Amblyomma aureolatum. Te most common clinical signs are apathy, hyperthermia and spontaneous bleeding. Anemia and thrombocytopenia are the most common hematological fndings. Tis work reports a clinical case of canine Rangeliosis treated at a private veterinary hospital, in São Paulo city in 2017. A dog was treated at a veterinary hospital in the north of São Paulo, with progressive weight loss, apathy and tail injury. Anemia and thrombocytopenia were observed on the hemogram. Rangelia vitalii DNA was detected in animal blood by real-time PCR (qPCR). In addition to the supportive treatment, doxycycline and subcutaneous imidocarb applications were used. Te sample collected afer treatment with the antibiotic continued to present protozoal DNA. Te disease should be considered as a diferential diagnosis and there is a great need for further studies about the therapy used.
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Abstract
Amblyomma aureolatum ticks are vectors of Rickettsia rickettsii, the etiologic agent of Rocky Mountain spotted fever in Brazil. Maintenance of R. rickettsii in nature depends on horizontal transmission along tick generations. Although such transmission is known to occur when uninfected and infected ticks feed simultaneously on susceptible animals (co-feeding systemic transmission), we investigated co-feeding nonsystemic transmission, which was based on R. rickettsii-infected and -uninfected A. aureolatum ticks feeding simultaneously on guinea pigs immune to R. rickettsii. Our acquisition and transmission infestations demonstrated that horizontal transmission of R. rickettsii by co-feeding ticks on immune hosts with no systemic infection did not occur when uninfected larvae fed distantly from infected nymphs but did occur in a few cases when uninfected larvae fed side-by-side with infected nymphs, suggesting that they shared the same feeding site. The co-feeding nonsystemic transmission type might have no epidemiologic importance for Rocky Mountain spotted fever.
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Barros-Battesti DM, Machado RZ, André MR, de Sousa KCM, Franze DA, Lima-Duarte L, Cirelli-Moraes A, Nunes PH, Labruna MB, Moraes-Filho J, Martins MM, Szabó MPJ. Successful Infection of Tick Cell Cultures of Rhipicephalus sanguineus (Tropical Lineage) with Ehrlichia canis. Vector Borne Zoonotic Dis 2018; 18:653-662. [PMID: 30222504 DOI: 10.1089/vbz.2017.2197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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 Ehrlichia canis. The epidemiological data of canine monocytic ehrlichiosis is congruent with the distribution of the two lineages of R. sanguineus. Herein, we report the infection of R. sanguineus (tropical lineage) cell cultures with E. canis, after cryopreservation. R. sanguineus (tropical lineage) cell identity was confirmed by sequencing using a 16S rDNA gene fragment. Tick cell cultures were prepared in L-15B medium supplemented with 10%, 15%, and 20% Fetal Bovine Serum (FBS), and 10% of Tryptose Phosphate Broth (TPB). Cell cultures developed better at the concentration of 20% of FBS. Cultures in the fifth harvest (approximately 7 months later) were selected for the first infections. Optimal R. sanguineus cell growth and adhesion was observed (5.0 × 106 cells/mL, and the population doubling time every 57 h). Once infected with E. canis, the cultures were maintained in L-15B medium supplemented with 2% and 5% of FBS fortified with iron and 10% TPB. Infected cells were also cryopreserved. DNA was extracted from infected and noninfected cells and analyzed using quantitative real-time PCR targeting the E. canis-dsb gene. Primary culture of the fifth passage was infected by E. canis and it maintained the pathogen for at least 40 days before partial cell destruction. Subcultures of infected cells (fresh and cryopreserved cultures) onto new tick cell cultures were successful. The E. canis infection was confirmed by real-time PCR and light and transmission electron microscopy. The R. sanguineus (tropical lineage) cells infected with E. canis successfully infected new tick cell cultures, showing that these cells could be an alternative substrate for maintenance of this pathogen.
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Affiliation(s)
- Darci Moraes Barros-Battesti
- 1 Department of Veterinary Pathology, Faculty of Agricultural and Veterinary Sciences, State University Julio de Mesquita Filho (UNESP) , Jaboticabal, Brazil
- 2 Laboratory of Parasitology, Butantan Institute , São Paulo, Brazil
| | - Rosangela Zacarias Machado
- 1 Department of Veterinary Pathology, Faculty of Agricultural and Veterinary Sciences, State University Julio de Mesquita Filho (UNESP) , Jaboticabal, Brazil
| | - Marcos Rogério André
- 1 Department of Veterinary Pathology, Faculty of Agricultural and Veterinary Sciences, State University Julio de Mesquita Filho (UNESP) , Jaboticabal, Brazil
| | - Keyla Carstens Marques de Sousa
- 1 Department of Veterinary Pathology, Faculty of Agricultural and Veterinary Sciences, State University Julio de Mesquita Filho (UNESP) , Jaboticabal, Brazil
| | | | | | | | - Pablo Henrique Nunes
- 3 Federal University of Latin American Integration-UNILA , Foz do Iguaçu, Brazil
| | - Marcelo Bahia Labruna
- 4 Department of Preventive Veterinary Medicine and Animal Science, School of Veterinary Medicine, University of São Paulo , São Paulo, Brazil
| | - Jonas Moraes-Filho
- 4 Department of Preventive Veterinary Medicine and Animal Science, School of Veterinary Medicine, University of São Paulo , São Paulo, Brazil
- 5 Veterinary Medicine, University of Santo Amaro , São Paulo, Brazil
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Silva AB, Vizzoni VF, Costa AP, Costa FB, Moraes-Filho J, Labruna MB, Gazêta GS, de Maria Seabra Nogueira R. First report of a Rickettsia asembonensis related infecting fleas in Brazil. Acta Trop 2017; 172:44-49. [PMID: 28427962 DOI: 10.1016/j.actatropica.2017.04.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 04/10/2017] [Accepted: 04/14/2017] [Indexed: 11/19/2022]
Abstract
The present study was performed in a non-endemic area for spotted fever (SF) in Imperatriz microregion, state of Maranhão, Brazil. Blood samples and ectoparasites were collected from 300 dogs of the Imperatriz microregion. Canine serum samples were tested individually by indirect immunofluorescence assay (IFA), using five Rickettsia isolates from Brazil. Antibodies reactive to at least one of the five species of Rickettsia were detected in 1.6% of the dogs (5/300). These sera were considered reactive to Rickettsia rickettsii and Rickettsia amblyommatis or very closely related species. The ticks (Acari: Ixodidae), identified as Rhipicephalus sanguineus sensu lato (Latreille), and the fleas, identified as Ctenocephalides felis, were tested by polymerase chain reaction (PCR) for detection of rickettsial DNA. More than 78% (83/106) of the C. felis fleas were found to be infected with Rickettsia species using gltA as rickettsial PCR targets, whereas no evidence of Rickettsia spp. was found in R. sanguineus s. l. Genetic analysis based on genes gltA, htrA and ompB showed that the detected strain, is most closely related to Rickettsia asembonensis (formerly Candidatus Rickettsia asemboensis). The present study is the first report of a R. asembonensis related infecting C. felis fleas in Brazil.
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Affiliation(s)
- Arannadia Barbosa Silva
- Programa de Pós-graduação do Mestrado em Ciência Animal, Universidade Estadual do Maranhão, São Luís, Maranhão, MA, Brazil; Fundação Oswaldo Cruz/Instituto Oswaldo Cruz (FIOCRUZ/IOC), Laboratório de Referência Nacional em Vetores das Riquetsioses (LIRN), Rio de Janeiro, RJ, Brazil
| | - Vinicius Figueiredo Vizzoni
- Fundação Oswaldo Cruz/Instituto Oswaldo Cruz (FIOCRUZ/IOC), Laboratório de Referência Nacional em Vetores das Riquetsioses (LIRN), Rio de Janeiro, RJ, Brazil
| | - Andréa Pereira Costa
- Programa de Pós-graduação do Mestrado em Ciência Animal, Universidade Estadual do Maranhão, São Luís, Maranhão, MA, Brazil
| | - Francisco Borges Costa
- Programa de Pós-graduação do Mestrado em Ciência Animal, Universidade Estadual do Maranhão, São Luís, Maranhão, MA, Brazil
| | - Jonas Moraes-Filho
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Marcelo Bahia Labruna
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Gilberto Salles Gazêta
- Fundação Oswaldo Cruz/Instituto Oswaldo Cruz (FIOCRUZ/IOC), Laboratório de Referência Nacional em Vetores das Riquetsioses (LIRN), Rio de Janeiro, RJ, Brazil
| | - Rita de Maria Seabra Nogueira
- Programa de Pós-graduação do Mestrado em Ciência Animal, Universidade Estadual do Maranhão, São Luís, Maranhão, MA, Brazil.
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Rotondano TEDF, Krawczak FDS, Barbosa WDO, Moraes-Filho J, Bastos FN, Labruna MB, Azevedo SSD, Melo MAD, Almeida AMPD. Ehrlichia canis and Rickettsia spp. in dogs from urban areas in Paraiba state, northeastern Brazil. ACTA ACUST UNITED AC 2017; 26:211-215. [PMID: 28658415 DOI: 10.1590/s1984-29612017030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Accepted: 04/26/2017] [Indexed: 11/21/2022]
Abstract
The aims of our study was to identify Ehrlichia canis and antibodies against Rickettsia spp. belonging to the spotted fever group (SFG) in dogs sampled from Paraiba state, northeastern Brazil. Blood and serum samples collected by convenience from dogs in urban areas of five municipalities were analyzed by real-time PCR for the detection of E. canis DNA and by immunofluorescence assay test (IFAT) for the identification of antibodies against Rickettsia rickettsii, R. felis, R. parkeri, R. amblyommii and R. rhipicephali antigens. E. canis DNA was detected in 8.9% (64/719) of the blood samples, whereas 5.63% (43/763) of the serum samples were positive for at least one of the Rickettsia antigens tested by IFAT. This study showed for the first time the occurrence of E. canis and suggested the circulation of SFG Rickettsia in dogs in the study region of Paraiba state, northeastern Brazil.
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Affiliation(s)
| | - Felipe da Silva Krawczak
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | | | - Jonas Moraes-Filho
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Fernanda Nieri Bastos
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Marcelo Bahia Labruna
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Sérgio Santos de Azevedo
- Unidade Acadêmica de Medicina Veterinária, Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande - UFCG, Patos, PB, Brasil
| | - Marcia Almeida de Melo
- Unidade Acadêmica de Medicina Veterinária, Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande - UFCG, Patos, PB, Brasil
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Costa FB, da Costa AP, Moraes-Filho J, Martins TF, Soares HS, Ramirez DG, Dias RA, Labruna MB. Rickettsia amblyommatis infecting ticks and exposure of domestic dogs to Rickettsia spp. in an Amazon-Cerrado transition region of northeastern Brazil. PLoS One 2017; 12:e0179163. [PMID: 28594882 PMCID: PMC5464615 DOI: 10.1371/journal.pone.0179163] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 05/24/2017] [Indexed: 01/01/2023] Open
Abstract
This study was performed in Maranhão state, a transition area two Brazilian biomes, Amazon and Cerrado. During 2011-2013, 1,560 domestic dogs were sampled for collection of serum blood samples and ticks in eight counties (3 within the Amazon and 5 within the Cerrado). A total of 959 ticks were collected on 150 dogs (9.6%). Rhipicephalus sanguineus sensu lato (s.l.) was the most abundant tick (68% of all collected specimens), followed by Amblyomma cajennense sensu lato (s.l.) (12.9%), Amblyomma parvum (9.2%), and Amblyomma ovale (5.2%). Other less abundant species (<1%) were Amblyomma oblongoguttatum, Rhipicephalus microplus, Haemaphysalis juxtakochi, and Amblyomma rotundatum. Females of A. cajennense s.l. ticks were morphologically identified as A. cajennense sensu stricto (s.s.) or A. sculptum. Molecular analyses of 779 canine ticks revealed three Rickettsia species: Rickettsia amblyommatis in 1% (1/100) A. cajennense s.l., 'Candidatus Rickettsia andeanae' in 20.7% (12/58) A. parvum, Rickettsia bellii in 6.8% (3/44) A. ovale and 100% (1/1) A. rotundatum ticks. An additional collection of A. sculptum from horses in a Cerrado area, and A. cajennense s.s. from pigs in an Amazon area revealed R. amblyommatis infecting only the A. cajennense s.s. ticks. Serological analysis of the 1,560 canine blood samples revealed 12.6% canine seroreactivity to Rickettsia spp., with the highest specific seroreactivity rate (10.2%) for R. amblyommatis. Endpoint titers to R. amblyommatis were significantly higher than those for the other Rickettsia antigens, suggesting that most of the seroreactive dogs were exposed to R. amblyommatis-infected ticks. Highest canine seroreactivity rates per locality (13.1-30.8%) were found in Amazon biome, where A. cajennense s.s. predominated. Lowest seroreactivity rates (1.9-6.5%) were found in Cerrado localities that were further from the Amazon, where A. sculptum predominated. Multivariate analyses revealed that canine seroreactivity to Rickettsia spp. or R. amblyommatis was statistically associated with rural dogs, exposed to Amblyomma ticks.
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Affiliation(s)
- Francisco B Costa
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
- Preventive Veterinary Medicine, Faculty of Veterinary Medicine, State University of Maranhão, São Luís, MA, Brazil
| | - Andréa P da Costa
- Preventive Veterinary Medicine, Faculty of Veterinary Medicine, State University of Maranhão, São Luís, MA, Brazil
| | - Jonas Moraes-Filho
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
- Mestrado em Medicina e Bem estar animal, Universidade Santo Amaro, Av. Prof. Eneas de Siqueira Neto, São Paulo, Brazil
| | - Thiago F Martins
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Herbert S Soares
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Diego G Ramirez
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Ricardo A Dias
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Marcelo B Labruna
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
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Guimarães MF, Araujo ADC, Freire DP, Machado DM, Martins NN, Moraes-Filho J, Horta MC. Investigação sorológica de Rickettsia rickettsii e Coxiella burnetii em caprinos e ovinos no entorno do Parque Nacional da Serra das Confusões, Piauí. Pesq Vet Bras 2017. [DOI: 10.1590/s0100-736x2017000600004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
RESUMO: As doenças causadas por bactérias dos gêneros Rickettsia e Coxiella possuem como vetores artrópodes hematófagos, na sua maioria carrapatos, que atuam diretamente na transmissão de patógenos responsáveis por enfermidades de grande impacto na medicina veterinária e humana. O presente estudo objetivou realizar uma investigação sorológica de Rickettsia rickettsii e Coxiella burnetii em caprinos e ovinos criados no entorno do Parque Nacional da Serra das Confusões (PNSC), localizado no estado do Piauí, região nordeste do Brasil. Amostras de soro de 202 caprinos e 153 ovinos foram testadas pela Reação de Imunofluorescência Indireta (RIFI) para detecção de anticorpos anti-R. rickettsii e anti-C. burnetii, sendo consideradas positivas quando apresentaram títulos ≥ 64. Carrapatos em fase de parasitismo foram coletados e identificados. Todas as amostras de caprinos e ovinos foram soronegativas para antígenos de R. rickettsii. Foi verificado soropositividade em 2% (3/153) das amostras de ovinos para C. burnetii, com títulos variando de 64 a 4.096. As amostras de caprinos não foram reagentes ao referido antígeno. Não foi observado parasitismo em caprinos por carrapatos. No total, foram coletados 56 carrapatos parasitando 15 ovinos (9,8%), todos identificados como Rhipicephalus microplus. O estudo demonstrou a ausência de anticorpos anti-R. rickettsii nas amostras de caprinos e ovinos, ausência de anticorpos anti-C. burnetii em caprinos; e possibilitou o primeiro relato da ocorrência sorológica de C. burnetii em ovinos nesta região do Brasil.
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da Costa AP, Costa FB, Labruna MB, Silveira I, Moraes-Filho J, Soares JF, Spolidorio MG, Guerra RDMSNDC. A serological and molecular survey of Babesia vogeli, Ehrlichia canis and Rickettsia spp. among dogs in the state of Maranhão, northeastern Brazil. ACTA ACUST UNITED AC 2017; 24:28-35. [PMID: 25909250 DOI: 10.1590/s1984-29612015008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 01/12/2015] [Indexed: 11/22/2022]
Abstract
This study evaluated exposure and infection by tick-borne agents (Babesia vogeli, Ehrlichia canis and Rickettsia spp.) in 172 dogs in rural areas and 150 dogs in urban areas of the municipality of Chapadinha, state of Maranhão, northeastern Brazil, using molecular and serological methods. Overall, 16.1% of the sampled dogs (52/322) were seroreactive to B. vogeli, with endpoint titers ranging from 40 to 640. For E. canis, 14.6% of the dogs (47/322) were seroreactive, with endpoint titers from 80 to 163,840. Antibodies reactive to at least one of the five species of Rickettsia were detected in 18.9% of the dogs (61/322), with endpoint titers ranging from 64 to 4,096. High endpoint titers were observed for Rickettsia amblyommii. Three (0.9%) and nine (2.8%) canine blood samples were PCR-positive for Babesia spp. and E. canis. The ticks collected from urban dogs were all Rhipicephalus sanguineus sensu lato, whereas the rural dogs were infested by R. sanguineus s.l, Amblyomma cajennense sensu lato and Amblyomma ovale. One A. ovale tick was found to be infected by Rickettsia bellii. This study provides an epidemiological background for controlling and preventing canine tick-borne diseases in a neglected region of Brazil.
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Affiliation(s)
- Andréa Pereira da Costa
- Laboratório de Doenças Parasitárias, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Francisco Borges Costa
- Laboratório de Doenças Parasitárias, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Marcelo Bahia Labruna
- Laboratório de Doenças Parasitárias, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Iara Silveira
- Laboratório de Doenças Parasitárias, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Jonas Moraes-Filho
- Laboratório de Doenças Parasitárias, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo, São Paulo, SP, Brasil
| | - João Fábio Soares
- Laboratório de Doenças Parasitárias, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Mariana Granziera Spolidorio
- Laboratório de Doenças Parasitárias, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo, São Paulo, SP, Brasil
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Abstract
A febre maculosa brasileira (FMB) é uma doença infecciosa transmitida por carrapatos do gênero Amblyomma, tendo como principal agente etiológico a bactéria Rickettsia rickettsii, manifestando-se por um quadro febril agudo. O primeiro relato de riquetsiose no Brasil foi em 1900, no Instituto Bacteriológico de São Paulo, pelo Dr. Adolfo Lutz. A doença reemergiu e se tornou um importante problema de saúde pública no Brasil a partir da década de 1980. Desde então, observou-se aumento no número de casos, expansão das áreas de transmissão, transmissão em áreas urbanas e, em especial, elevadas taxas de letalidade. As rickettsias são bactérias intracelulares obrigatórias, com predisposição ao parasitismo de células endoteliais, que estão classicamente divididas em três grupos: o grupo tifo, composto por Rickettsia prowazekii e Rickettsia typhi; o grupo da febre maculosa, que inclui mais de 20 espécies válidas, principalmente associadas aos carrapatos (por exemplo, R. rickettsii e R. parkeri); e um grupo mais basal, em que estão incluídas R. bellii, R. monteiroi e R. canadensis. No Brasil, a transmissão da FMB está associada aos carrapatos do gênero Amblyomma, e as espécies de maior importância na transmissão da doença são A. sculptum (antigo A. cajennense) e A. aureolatum. A doença se caracteriza por febre, mialgia e cefaleia intensa, exantema, edema nas mãos e nos pés, sendo que em alguns casos apresenta-se de maneira generalizada. A doença causa sepse com comprometimento pulmonar, podendo ocasionar insuficiência respiratória aguda, problemas renais, como insuficiência renal aguda, diátese hemorrágica, lesões neurológicas com meningite, encefalite e icterícia. Os casos clínicos que evoluem para óbito, devido a diagnóstico e tratamento tardios, normalmente ocorrem entre o 5° e o 15° dias após o início dos sintomas. O diagnóstico da doença é feito com o emprego da reação de imunofluorescência indireta (RIFI), reação em cadeia da polimerase (PCR) e isolamento em cultivo celular. Após início das manifestações clínicas, o tratamento deve ser iniciado precocemente, interrompendo a administração após dois ou três dias do desaparecimento da febre. As medidas de vigilância e controle devem focar ações educativas e divulgar a doença para a população e os profissionais da saúde, repassando conhecimentos sobre sua existência, sobre medidas preventivas e sobre a importância do enviar carrapatos coletados nos pacientes ou encontrados no ambiente para identificá-los.
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Labruna MB, Gerardi M, Krawczak FS, Moraes-Filho J. Comparative biology of the tropical and temperate species of Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) under different laboratory conditions. Ticks Tick Borne Dis 2016; 8:146-156. [PMID: 27793613 DOI: 10.1016/j.ttbdis.2016.10.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 10/23/2016] [Accepted: 10/23/2016] [Indexed: 11/25/2022]
Abstract
Recent studies have shown that the taxon Rhipicephalus sanguineus sensu lato (s.l.) is represented in Latin America by two distinct species, designated as 'tropical species' (distributed from Mexico to Brazil) and 'temperate species' (restricted to the southern cone of South America). Since both tropical and temperate species of R. sanguineus s.l. are parasites primarily of domestic dogs, the reasons for their distinct geographical distribution in South America could be related to particular requirements of abiotic conditions for off-host development. With the purpose to test this hypothesis, this study evaluated the off-host developmental stages (eggs, engorged larvae, nymphs and females) of both tick species simultaneously inside incubators with temperature and photoperiod regimens that simulated the summer and winter conditions of tropical Brazil (where the 'tropical species' occurs) and temperate Brazil (where the 'temperate species' occurs). Results showed that the temperate species had significantly higher survival rates than the tropical species, when engorged ticks (larvae, nymphs and females) and eggs were incubated at lower temperatures simulating winter seasons of many parts of the southern cone of South America, where the temperate species is known to occur. These results suggest that the absence of established populations of the tropical species in temperate areas of South America is related to the low overwinter capacity of the tropical species in those areas. Regarding the temperate species, unfed adults that molted from nymphs under summer conditions of either tropical or temperate Brazil remained dormant, at the state of behavioral diapause for at least 20 weeks. Contrastingly, when engorged nymphs of the temperate species were held at winter conditions for at least 3 months, and then transferred to summer conditions to complete molting, no diapause was observed in adult ticks. These results were corroborated by infestation trials, which showed that diapausing adult ticks took more days to attach to rabbits, and did in lesser numbers, when compared to nondiapausing adult ticks. Contextualization of our results in the current literature suggests that absence of established populations of the temperate species in tropical Brazil is linked to the fact that adult ticks would become inactive (diapause) right after molting from nymphs at any period of the year. On the other hand, absence of established populations of the tropical species in temperate Brazil is linked to the fact that this tick species would not enter diapause, and therefore, could not synchronize its life-cycle to avoid the lethal effects of a more severe winter on its developmental stages. Indeed, such assumptions should be corroborated by additional studies testing different populations of the tropical and temperate species, including more studies under natural conditions.
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Affiliation(s)
- Marcelo B Labruna
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87 Cidade Universitária, CEP: 05508-270, São Paulo, Brazil.
| | - Monize Gerardi
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87 Cidade Universitária, CEP: 05508-270, São Paulo, Brazil
| | - Felipe S Krawczak
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87 Cidade Universitária, CEP: 05508-270, São Paulo, Brazil
| | - Jonas Moraes-Filho
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87 Cidade Universitária, CEP: 05508-270, São Paulo, Brazil
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Krawczak FS, Binder LC, Oliveira CS, Costa FB, Moraes-Filho J, Martins TF, Sponchiado J, Melo GL, Gregori F, Polo G, Oliveira SV, Labruna MB. Ecology of a tick-borne spotted fever in southern Brazil. Exp Appl Acarol 2016; 70:219-229. [PMID: 27392739 DOI: 10.1007/s10493-016-0070-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 07/05/2016] [Indexed: 06/06/2023]
Abstract
Rio Grande do Sul is the southernmost state of Brazil, bordering Uruguay. Clinical cases of spotted fever group (SFG) rickettsiosis were recently reported in Rio Grande do Sul. None of these cases was lethal, and all were confirmed by seroconversion to R. rickettsii antigens. Because serological cross-reactions are well known to occur between different SFG agents, the SFG agent responsible for the clinical cases remains unknown in Rio Grande do Sul, where no rickettsial agent is known to infect ticks. During 2013-2014, ticks and blood sera samples were collected from domestic dogs and wild small mammals, and from the vegetation in a SFG-endemic area of Rio Grande do Sul. Dogs were infested by Amblyomma ovale adult ticks, whereas small mammals were infested by immature stages of A. ovale, Ixodes loricatus, and adults of I. loricatus. Ticks collected on vegetation were adults of A. ovale, and immature stages of A. ovale, Amblyomma dubitatum, and Amblyomma longirostre. Three Rickettsia species were detected: Rickettsia bellii in I. loricatus, Rickettsia amblyommii in A. longirostre, and a Rickettsia parkeri-like agent (Rickettsia sp. strain Atlantic rainforest) in A. ovale. Seroreactivity to SFG antigens were detected in 19.7 % (27/137) canine and 37.5 % (15/40) small mammal sera, with highest titers to R. parkeri. Results indicate that the R. parkeri-like agent, strain Atlantic rainforest, is circulating between A. ovale ticks, dogs and small mammals in the study area, suggesting that this SFG pathogen could be one of the etiological agents of SFG clinical cases in Rio Grande do Sul.
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Affiliation(s)
- Felipe S Krawczak
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, 05508-270, Brazil
| | - Lina C Binder
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, 05508-270, Brazil
| | - Caroline S Oliveira
- Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Francisco B Costa
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, 05508-270, Brazil
| | - Jonas Moraes-Filho
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, 05508-270, Brazil
- Mestrado em Medicina Veterinária e Bem Estar Animal, Universidade de Santo Amaro, São Paulo, SP, Brazil
| | - Thiago F Martins
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, 05508-270, Brazil
| | - Jonas Sponchiado
- Departamento de Biologia, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Geruza L Melo
- Departamento de Ecologia, Universidade Federal do Mato Grosso do Sul, Campo Grande, MS, Brazil
| | - Fábio Gregori
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, 05508-270, Brazil
| | - Gina Polo
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, 05508-270, Brazil
| | - Stefan V Oliveira
- Secretaria de Vigilância em Saúde, Ministério da Saúde, Brasília, DF, Brazil
| | - Marcelo B Labruna
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, 05508-270, Brazil.
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Ueno TEH, Costa FB, Moraes-Filho J, Agostinho WC, Fernandes WR, Labruna MB. Experimental infection of horses with Rickettsia rickettsii. Parasit Vectors 2016; 9:499. [PMID: 27624315 PMCID: PMC5022194 DOI: 10.1186/s13071-016-1784-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 08/30/2016] [Indexed: 11/10/2022] Open
Abstract
Background Rickettsia rickettsii is vectored by ticks, and some vertebrate hosts can be sources of infection to ticks during bacteremic periods. In Brazil, the main vector for R. rickettsii is the tick Amblyomma sculptum, a member of the A. cajennense complex. Horses, in turn, are one of the major hosts for A. sculptum. In this study, horses experimentally infected with R. rickettsii were assessed for clinical changes and their capability to transmit the infection to A. sculptum ticks. Methods Four horses were infected with R. rickettsii through either intraperitoneal injection or infestation with R. rickettsii-infected A. sculptum ticks. Simultaneously, the animals were infested with non-infected A. sculptum ticks. The horses were monitored for 30 days by clinical examination, hematological and biochemical tests, real-time PCR of blood for the detection of Rickettsia, and inoculation of blood in guinea pigs. IgG antibody titers were followed until the horses have shown seronegativity or until the end of the experiment. Uninfected ticks that fed on horses were subjected to real-time PCR and/or were fed on susceptible rabbits. Results The horses showed no clinical, hematological or blood biochemical alterations, and bacteremia was not detected by real-time PCR or by inoculation of horse blood into guinea pigs. Anti-R. rickettsii antibodies were detected in horses from 10 days to 2 years after infection. Uninfected ticks, after feeding on infected horses, showed 2.1 % positivity in real-time PCR, but failed to transmit the infection to rabbits at a next feeding stage. Conclusions Rickettsia rickettsii-infected horses did not manifest illness and are not competent amplifier hosts of R. rickettsii for A. sculptum ticks.
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Affiliation(s)
| | - Francisco B Costa
- Faculty of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
| | - Jonas Moraes-Filho
- Faculty of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
| | | | | | - Marcelo B Labruna
- Faculty of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
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21
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Araes-Santos AI, Moraes-Filho J, Peixoto RM, Spolidorio MG, Azevedo SS, Costa MM, Labruna MB, Horta MC. Ectoparasite Infestations and Canine Infection by Rickettsiae and Ehrlichiae in a Semi-Arid Region of Northeastern Brazil. Vector Borne Zoonotic Dis 2016; 15:645-51. [PMID: 26565771 DOI: 10.1089/vbz.2015.1786] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This study investigated the prevalence of Rickettsia spp. and Ehrlichia canis infection in dogs and their ectoparasites from rural and urban areas of two municipalities, Petrolina and Juazeiro, within a semiarid region (Caatinga biome) of northeastern Brazil, by immunofluorescence assay (IFA) and polymerase chain reaction (PCR). Overall, 12.1% (61/504) and 23.0% (116/504) of canine plasma samples had antibodies reactive to Rickettsia spp. and E. canis. E. canis DNA was detected by PCR in 8.3% (42/504) of canine blood samples, whereas no blood sample was positive for Rickettsia spp. The infection by E. canis was determined by PCR in 4.9% (14/285) Rhipicephalus sanguineus sensu lato (s.l.) ticks and by Rickettsia felis in 1.1% (3/285) and 40.6% (74/182) ticks and fleas, respectively. Multivariate regression analyses revealed that canine seropositivity to Rickettsia spp. was associated statistically with the variables "to reside in Petrolina" and "presence of ectoparasites." Our results indicate that canine infection by E. canis might be endemic in the Caatinga biome as it is in other Brazilian biomes. Although no previous serosurvey for Rickettsia spp. has been conducted on dogs from the Caatinga biome, our values are much lower than the ones reported for rural dogs from other Brazilian biomes. These differences are likely related to the semiarid climate of the aatinga biome, which minimizes the exposure of rural dogs to Amblyomma spp. ticks, the most common vectors of Rickettsia spp. in Brazil. Considering that dogs are excellent sentinels for human exposure to Rickettsia spp., we can infer that the risks of human acquiring tick-borne rickettsiosis in the Caatinga region of the present study are low. The rickettsial infection rates in fleas and ticks were not related to canine seropositivity; i.e., areas with higher Rickettsia infection rates in fleas had the lowest canine seroreactivity to Rickettsia spp.
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Affiliation(s)
- Ana Isabel Araes-Santos
- 1 Laboratório de Doenças Parasitárias, Universidade Federal do Vale do São Francisco , Petrolina, Pernambuco, Brazil
| | - Jonas Moraes-Filho
- 2 Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo , São Paulo, São Paulo, Brazil
| | - Renata M Peixoto
- 3 Laboratório de Doenças Infecciosas, Universidade Federal do Vale do São Francisco , Petrolina, Pernambuco, Brazil
| | - Mariana G Spolidorio
- 2 Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo , São Paulo, São Paulo, Brazil
| | - Sérgio S Azevedo
- 4 Unidade Acadêmica de Medicina Veterinária, Universidade Federal de Campina Grande , Patos, Paraíba, Brazil
| | - Mateus M Costa
- 3 Laboratório de Doenças Infecciosas, Universidade Federal do Vale do São Francisco , Petrolina, Pernambuco, Brazil
| | - Marcelo B Labruna
- 2 Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo , São Paulo, São Paulo, Brazil
| | - Mauricio C Horta
- 1 Laboratório de Doenças Parasitárias, Universidade Federal do Vale do São Francisco , Petrolina, Pernambuco, Brazil
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22
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Nieri-Bastos FA, Horta MC, Barros-Battesti DM, Moraes-Filho J, Ramirez DG, Martins TF, Labruna MB. Isolation of the Pathogen Rickettsia sp. Strain Atlantic Rainforest From Its Presumed Tick Vector, Amblyomma ovale (Acari: Ixodidae), From Two Areas of Brazil. J Med Entomol 2016; 53:977-981. [PMID: 27146681 DOI: 10.1093/jme/tjw062] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 04/04/2016] [Indexed: 06/05/2023]
Abstract
In this study, Amblyomma ovale Koch ticks were collected from domestic dogs in two localities of the Atlantic rainforest biome of Brazil: 1) the Paty Valley of the Chapada Diamantina National Park, Bahia state (northeastern Brazil), and 2) Adrianópolis, Paraná state (southern Brazil). Ticks were screened for the presence of Rickettsia-like structures by the hemolymph test with Giménez staining, and then processed for isolation of rickettsiae in Vero cell culture by the shell-vial technique. Rickettsiae were isolated from one A. ovale tick of each of the two localities. The two isolates were successfully established in the laboratory with several passages, each one reaching >90% infection of the cells. The two isolates were identified as the spotted fever group (SFG) agent Rickettsia sp. strain Atlantic rainforest, as their gltA (350 bp), ompB (781 bp), and ompA (567 bp) gene fragments were 100% equal to GenBank corresponding sequences of the original strain Atlantic rainforest, reported to be infecting a human in southeastern Brazil, and also 100% equal to the available ompA sequence of strain Bahia, reported to be infecting a human in Paty Valley, the same area of the present study in Bahia state. Ten dogs from Paty Valley were serologically tested against rickettsial antigens by the indirect immunofluorescence antibody test. At least 60% of them were seroreactive to SFG rickettsiae. The role of A. ovale as vector of Rickettsia sp. strain Atlantic rainforest in the Paty Valley area, as well as in other parts of Latin America, is discussed.
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Affiliation(s)
- Fernanda A Nieri-Bastos
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil (; ; ; )
| | - Maurício C Horta
- Laboratory of Parasitic Diseases, Federal University of Vale do São Francisco, Petrolina, Pernambuco, Brazil
| | | | - Jonas Moraes-Filho
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil (; ; ; )
- Santo Amaro University - UNISA, São Paulo, SP, Brazil, and
| | - Diego G Ramirez
- Laboratory of Parasitology, Butantan Institute, São Paulo, SP, Brazil (; )
| | - Thiago F Martins
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil (; ; ; )
| | - Marcelo B Labruna
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil (; ; ; ),
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23
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Krawczak FS, Muñoz-Leal S, Guztzazky AC, Oliveira SV, Santos FCP, Angerami RN, Moraes-Filho J, de Souza JC, Labruna MB. Rickettsia sp. Strain Atlantic Rainforest Infection in a Patient from a Spotted Fever-Endemic Area in Southern Brazil. Am J Trop Med Hyg 2016; 95:551-3. [PMID: 27325804 DOI: 10.4269/ajtmh.16-0192] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 05/17/2016] [Indexed: 11/07/2022] Open
Abstract
Santa Catarina State in southern Brazil is the state with the second highest number of laboratory-confirmed cases of spotted fever illness in Brazil. However, all these cases were confirmed solely by serological analysis (seroconversion to spotted fever group rickettsiae), which has not allowed identification of the rickettsial agent. Here, a clinical case of spotted fever illness from Santa Catarina is shown by seroconversion and molecular analysis to be caused by Rickettsia sp. strain Atlantic rainforest. This is the third confirmed clinical case due to this emerging rickettsial agent in Brazil. Like the previous two cases, the patient presented an inoculation eschar at the tick bite site. Our molecular diagnosis was performed on DNA extracted from the crust removed from the eschar. These results are supported by previous epidemiological studies in Santa Catarina, which showed that nearly 10% of the most common human-biting ticks were infected by Rickettsia sp. strain Atlantic rainforest.
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Affiliation(s)
- Felipe S Krawczak
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil
| | - Sebastián Muñoz-Leal
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil
| | | | - Stefan V Oliveira
- Secretaria de Vigilância em Saúde, Ministério da Saúde, Brasília, Distrito Federal, Brazil
| | | | - Rodrigo N Angerami
- Hospital das Clínicas, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Jonas Moraes-Filho
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil
| | - Julio C de Souza
- Fundação Universidade Regional de Blumenau, Blumenau, Santa Catarina, Brazil
| | - Marcelo B Labruna
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil.
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Coelho MG, Ramos VDN, Limongi JE, de Lemos ERS, Guterres A, da Costa Neto SF, Rozental T, Bonvicino CR, D'Andrea PS, Moraes-Filho J, Labruna MB, Szabó MPJ. Serologic evidence of the exposure of small mammals to spotted-fever Rickettsia and Rickettsia bellii in Minas Gerais, Brazil. J Infect Dev Ctries 2016; 10:275-82. [PMID: 27031460 DOI: 10.3855/jidc.7084] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 10/02/2015] [Accepted: 10/02/2015] [Indexed: 10/31/2022] Open
Abstract
INTRODUCTION Sources of pathogenic Rickettsia in wildlife are largely unknown in Brazil. In this work, potential tick vectors and seroreactivity of small mammals against four spotted-fever group Rickettsia (R. rickettsii, R. parkeri, R. amblyommii and R. rhipicephali) and Rickettsia bellii from peri-urban areas of Uberlândia, a major town in Brazil, are described for the first time. METHODOLOGY Small mammals were captured and blood samples collected. Ticks were collected from the surface of the host and the environment and posteriorly identified. Reactivity of small mammal sera to Rickettsia was tested by indirect immunofluorescence assay (IFA) using crude antigens from five Brazilian Rickettsia isolates. RESULTS Information was obtained from 416 small mammals (48 Marsupialia and 368 Rodentia). Forty-eight animals were parasitized and two tick species, Ixodes loricatus and Amblyomma dubitatum, were found on several host species, with a few tick-host relationships described for the first time. From the 416 tested sera, 70 reacted to at least one Rickettsia antigen (prevalence of 16.8%) and from these, 19 (27.1%) reacted to two or more antigens. Seroprevalence was higher for marsupials (39.6%) than for rodents (13.8%). Marsupial and Rhipidomys spp. sera reacted mainly (highest seroprevalence and titers) to R. bellii, and that of Necromys lasiurus mainly to R. rickettsii. CONCLUSIONS Although the serologic assays poorly discriminate between closely related spotted-fever group Rickettsia, the observed small mammal seroreactivity suggests the circulation of Rickettsia in the peri-urban area of Uberlândia, albeit at low levels.
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Krawczak FS, Agostinho WC, Polo G, Moraes-Filho J, Labruna MB. Comparative evaluation of Amblyomma ovale ticks infected and noninfected by Rickettsia sp. strain Atlantic rainforest, the agent of an emerging rickettsiosis in Brazil. Ticks Tick Borne Dis 2016; 7:502-7. [PMID: 26895674 DOI: 10.1016/j.ttbdis.2016.02.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 01/29/2016] [Accepted: 02/04/2016] [Indexed: 10/22/2022]
Abstract
In 2010, a novel spotted fever group rickettsiosis was reported in the Atlantic rainforest coast of Brazil. The etiological agent was identified as Rickettsia sp. strain Atlantic rainforest, and the tick Amblyomma ovale was incriminated as the presumed vector. The present study evaluated under laboratory conditions four colonies of A. ovale: two started from engorged females that were naturally infected by Rickettsia sp. strain Atlantic rainforest (designated as infected groups); the two others started from noninfected females (designated as control groups). All colonies were reared in parallel from F0 engorged female to F2 unfed nymphs. Tick-naïve vesper mice (Calomys callosus) or domestic rabbits were used for feeding of each tick stage. Rickettsia sp. strain Atlantic rainforest was preserved by transstadial maintenance and transovarial transmission in A. ovale ticks for at least 2 generations (from F0 females to F2 nymphs), because nearly 100% of the tested larvae, nymphs, and adults from the infected groups were shown by PCR to contain rickettsial DNA. All vesper mice and rabbits infested by larvae and nymphs, and 50% of the rabbits infested by adults from the infected groups seroconverted, indicating that these tick stages were vector competent for Rickettsia sp. strain Atlantic rainforest. Expressive differences in mortality rates and reproductive performance were observed between engorged females from the infected and control groups, as indicated by 75.0% and 97.1% oviposition success, respectively, and significantly lower egg mass weight, conversion efficiency index, and percentage of egg hatching for the infected groups. Our results indicate that A. ovale can act as a natural reservoir for Rickettsia sp. strain Atlantic rainforest. However, due to deleterious effect caused by this rickettsial agent on engorged females, amplifier vertebrate hosts might be necessary for persistent perpetuation of Rickettsia sp. strain Atlantic rainforest in A. ovale under natural conditions.
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Affiliation(s)
- Felipe S Krawczak
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, , Av. Prof. Orlando Marques de Paiva, 87 Cidade Universitária, CEP: 05508-270 São Paulo, SP, Brazil
| | - Washington C Agostinho
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, , Av. Prof. Orlando Marques de Paiva, 87 Cidade Universitária, CEP: 05508-270 São Paulo, SP, Brazil
| | - Gina Polo
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, , Av. Prof. Orlando Marques de Paiva, 87 Cidade Universitária, CEP: 05508-270 São Paulo, SP, Brazil
| | - Jonas Moraes-Filho
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, , Av. Prof. Orlando Marques de Paiva, 87 Cidade Universitária, CEP: 05508-270 São Paulo, SP, Brazil; Universidade de Santo Amaro, R. Prof. Enéas de Siqueira Neto, 340, CEP: 04829-300 São Paulo, SP, Brazil
| | - Marcelo B Labruna
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, , Av. Prof. Orlando Marques de Paiva, 87 Cidade Universitária, CEP: 05508-270 São Paulo, SP, Brazil.
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Moraes-Filho J, Krawczak FS, Costa FB, Soares JF, Labruna MB. Comparative Evaluation of the Vector Competence of Four South American Populations of the Rhipicephalus sanguineus Group for the Bacterium Ehrlichia canis, the Agent of Canine Monocytic Ehrlichiosis. PLoS One 2015; 10:e0139386. [PMID: 26414283 PMCID: PMC4587558 DOI: 10.1371/journal.pone.0139386] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 09/11/2015] [Indexed: 11/25/2022] Open
Abstract
This study compared the vector competence of four populations of Rhipicephalus sanguineus group ticks for the bacterium Ehrlichia canis, the agent of canine monocytic ehrlichiosis (CME). Ticks (larvae and nymphs) from the four populations—one from São Paulo state, southeastern Brazil (BSP), one from Rio Grande do Sul state, southern Brazil (BRS), one from Argentina (ARG), and one from Uruguay (URU)–were exposed to E. canis infection by feeding on dogs that were experimentally infected with E. canis. Engorged ticks (larvae and nymphs) were allowed to molt to nymphs and adults, respectively, which were tested by molecular analysis (E. canis-specific PCR assay) and used to infest naïve dogs. Through infestation of adult ticks on naïve dogs, after nymphal acquisition feeding on E. canis-infected dogs, only the BSP population was shown to be competent vectors of E. canis, i.e., only the dogs infested with BSP adult ticks developed clinical illness, seroconverted to E. canis, and yielded E. canis DNA by PCR. This result, demonstrated by two independent replications, is congruent with epidemiological data, since BSP ticks were derived from São Paulo state, Brazil, where CME is highly endemic. On the other hand, BRS, ARG, and URU ticks were derived from a geographical region (South America southern cone) where CME has never been properly documented. Molecular analysis of unfed adults at 30 days post molting support these transmission results, since none of the BRS, ARG, and URU ticks were PCR positive, whereas 1% of the BSP nymphs and 31.8% of the BSP adults contained E. canis DNA. We conclude that the absence or scarcity of cases of CME due to E. canis in the South America southern cone is a result of vector incompetence of the R. sanguineus group ticks that prevail on dogs in this part of South America.
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Affiliation(s)
- Jonas Moraes-Filho
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Felipe S. Krawczak
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
| | - Francisco B. Costa
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
| | | | - Marcelo B. Labruna
- Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP, Brazil
- * E-mail:
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Oliveira RSD, Cunha RC, Moraes-Filho J, Gonçales RA, Lara APDSSD, Avila LFDCD, Labruna MB, Leite FPL. Recombinant gp19 as a potential antigen for detecting anti-Ehrlichia canis antibodies in dog sera. Rev Bras Parasitol Vet 2015; 24:290-7. [PMID: 26291145 DOI: 10.1590/s1984-29612015055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The canine monocytic ehrlichiosis, caused by Ehrlichia canis, is endemic in several regions of Brazil. Some serological diagnostic techniques using immunodominant proteins of E. canis as antigens are available, but their specificities and sensitivities are questionable. Based on this, the objective of this study was to test the antigenic potential of the recombinant gp19 protein (rGP19) for subsequent use in diagnostic tests. The rGP19 expressed in the Escherichia coli strain BL21 (DE3) C41 was recognized in the sera from experimentally infected dogs using ELISA and Western blotting. Thus, it was possible to obtain a promising antigen with the ability to differentiate between E. canis-positive and -negative animals, even 1 week after infection.
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Affiliation(s)
| | | | - Jonas Moraes-Filho
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, BR
| | - Relber Aguiar Gonçales
- Pós-graduação em Biologia Celular e Molecular, Universidade de São Paulo, São Paulo, SP, BR
| | | | | | - Marcelo Bahia Labruna
- Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, BR
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Bonoldi VLN, Marangoni RG, Gauditano G, Moraes-Filho J, Labruna MB, Yoshinari NH. First report of mild Brazilian spotted fever associated to arthritis. Rev Bras Reumatol 2014; 54:237-240. [PMID: 25054603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 02/18/2013] [Indexed: 06/03/2023] Open
Abstract
We describe the first Brazilian case of mild Rickettsiosis, complicated by knee monoarthritis, in young adult bitten by a tick on his left leg in Camburi zone, located in São Sebastião municipality, southern coastal region of the State of São Paulo, in the Atlantic rainforest region, Brazil. The patient developed inoculation eschar at the tick bite site associated with enlarged lymph nodes in the left groin, fever, polyarthralgia, headache and macular rash. Twenty days after tick bite episode, he displayed monoarthritis in his right knee. The diagnosis of mild Rickettsiosis was established by sequential immunological analysis in serum and synovial fluid, using the indirect immunofluorescence (IF) assay for antibodies reactive with Rickettsia parkeri and Rickettsia rickettsii. The mild Rickettsiosis is an emerging zoonosis, that must be investigated by physicians, including rheumatologists, in patients that present macular rash, fever and eventually arthritis, after visiting the southern coastal Atlantic rainforest region in Brazil.
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Affiliation(s)
| | | | - Giancarla Gauditano
- Departamento de Reumatologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Jonas Moraes-Filho
- Faculdade de Medicina Veterinária, Universidade de São Paulo, São Paulo, SP, Brasil
| | | | - Natalino Hajime Yoshinari
- Departamento de Reumatologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil
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29
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Krawczak FS, Nieri-Bastos FA, Nunes FP, Soares JF, Moraes-Filho J, Labruna MB. Rickettsial infection in Amblyomma cajennense ticks and capybaras (Hydrochoerus hydrochaeris) in a Brazilian spotted fever-endemic area. Parasit Vectors 2014; 7:7. [PMID: 24387674 PMCID: PMC3892071 DOI: 10.1186/1756-3305-7-7] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 01/01/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Brazilian spotted fever (BSF), caused by the bacterium Rickettsia rickettsii, is the deadliest spotted fever of the world. In most of the BSF-endemic areas, capybaras (Hydrochoerus hydrochaeris) are the principal host for the tick Amblyomma cajennense, which is the main vector of BSF. METHODS In 2012, a BSF case was confirmed in a child that was bitten by ticks in a residential park area inhabited by A. cajennense-infested capybaras in Itú municipality, southeastern Brazil. Host questing A. cajennense adult ticks were collected in the residential park and brought alive to the laboratory, where they were macerated and intraperitoneally inoculated into guinea pigs. A tick-inoculated guinea pig that presented high fever was euthanized and its internal organs were macerated and inoculated into additional guinea pigs (guinea pig passage). Tissue samples from guinea pig passages were also used to inoculate Vero cells through the shell vial technique. Infected cells were used for molecular characterization of the rickettsial isolate through PCR and DNA sequencing of fragments of three rickettsial genes (gltA, ompA, and ompB). Blood serum samples were collected from 172 capybaras that inhabited the residential park. Sera were tested through the immunofluorescence assay using R. rickettsii antigen. RESULTS A tick-inoculated guinea pig presented high fever accompanied by scrotal reactions (edema and marked redness). These signs were reproduced by consecutive guinea pig passages. Rickettsia was successfully isolated in Vero cells that were inoculated with brain homogenate derived from a 3rd passage-febrile guinea pig. Molecular characterization of this rickettsial isolate (designated as strain ITU) yielded DNA sequences that were all 100% identical to corresponding sequences of R. rickettsii in Genbank. A total of 83 (48.3%) out of 172 capybaras were seroreactive to R. rickettsii, with endpoint titers ranging from 64 to 8192. CONCLUSIONS A viable isolate of R. rickettsii was obtained from the tick A. cajennense, comprising the first viable R. rickettsi isolate from this tick species during the last 60 years. Nearly half of the capybara population of the residential park was seroreactive to R. rickettsii, corroborating the findings that the local A. cajennense population was infected by R. rickettsii.
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Affiliation(s)
- Felipe S Krawczak
- Department of Preventive Veterinary medicine and animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP 05508-270, Brazil
| | - Fernanda A Nieri-Bastos
- Department of Preventive Veterinary medicine and animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP 05508-270, Brazil
| | - Fernanda P Nunes
- Veterinary and Technical Responsible by the Association Fazenda Vila Real de Itu - Rodovia Marechal Rondon Km 113.5, Itu, SP 13312-901, Brazil
| | - João F Soares
- Department of Preventive Veterinary medicine and animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP 05508-270, Brazil
| | - Jonas Moraes-Filho
- Department of Preventive Veterinary medicine and animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP 05508-270, Brazil
| | - Marcelo B Labruna
- Department of Preventive Veterinary medicine and animal Health, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, SP 05508-270, Brazil
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Medeiros A, Moura A, Souza A, Bellato V, Sartor A, Vieira-Neto A, Moraes-Filho J, Labruna M. Antibodies against rickettsiae from spotted fever groups in horses from two mesoregions in the state of Santa Catarina, Brazil. ARQ BRAS MED VET ZOO 2013. [DOI: 10.1590/s0102-09352013000600019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Bacteria of the Rickettsia genus are agents of Brazilian Spotted Fever (BSF), a zoonotic disease which is difficult to diagnose, evolves quickly and can result in death. Antibodies against Rickettsia spp. in horses were studied, by means of Indirect Immunofluorescence Assay (IFAT ≥64), in 150 blood samples taken from animals in two Santa Catarina mesoregions (Planalto Serrano and Vale do Itajaí). The overall occurrence of Rickettsia spp. antibodies in horses was 18.66%, with cross-reactivity occurring in all positive samples for at least two of the species tested. Separately, according to the species, 25 (16.66%) samples were positive for R. rickettsii, 15 (10%) for R. parkeri, 22 (14.66%) for R. amblyommii, 23 (15.33%) for R. rhipicephali, 16 (10.66%) for R. bellii and 19 (12.66%) for R. felis. Only two animals resulted in a conclusive serodiagnosis, one for R. bellii and the other for R. rickettsii, at maximum dilutions of 1:4096 and 1:512, respectively. The occurrence of antibodies against Rickettsia spp. in horses from two mesoregions in the state of Santa Catarina indicates the movement of BSF agents in these sentinel animals and confirms the importance of studying spotted fever in the state of Santa Catarina.
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Affiliation(s)
| | - A.B. Moura
- Universidade do Estado de Santa Catarina
| | - A.P. Souza
- Universidade do Estado de Santa Catarina
| | - V. Bellato
- Universidade do Estado de Santa Catarina
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Santos LGFD, Melo ALT, Moraes-Filho J, Witter R, Labruna MB, Aguiar DMD. Molecular detection of Ehrlichia canisin dogs from the Pantanal of Mato Grosso State, Brazil. Rev Bras Parasitol Vet 2013; 22:114-8. [DOI: 10.1590/s1984-29612013005000013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 12/01/2012] [Indexed: 11/22/2022]
Abstract
The present study evaluated the presence of EhrlichiaDNA in the blood samples of 320 dogs from the urban and rural areas of the municipality of Poconé, Pantanal region, Mato Grosso state, by Polymerase Chain Reaction (PCR), targeting the ehrlichial dsbgene. Risk factors for infection in dogs were also evaluated. Forty-eight (15%, 95% CI: 11.4-19.5%) dogs were positive: 25 (15.6%, 95% CI: 10.4-22.2%) from the urban area and 23 (14.4%, 95% CI: 9.3-20.8%) from the rural area (P > 0.05). Partial DNA sequence obtained from PCR products of 18 samples from the urban area and 16 samples from the rural area were 100% identical to E. canis from Brazil and the USA. This study reports the first E. canis molecular detection in dogs from the northern Pantanal region.
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Affiliation(s)
| | - Andréia Lima Tomé Melo
- Universidade Federal de Mato Grosso – UFMT, Brasil; Universidade Federal de Mato Grosso – UFMT, Brasil
| | | | - Rute Witter
- Universidade Federal de Mato Grosso – UFMT, Brasil
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Pacheco RC, Arzua M, Nieri-Bastos FA, Moraes-Filho J, Marcili A, Richtzenhain LJ, Barros-Battesti DM, Labruna MB. Rickettsial infection in ticks (Acari: Ixodidae) collected on birds in southern Brazil. J Med Entomol 2012; 49:710-716. [PMID: 22679880 DOI: 10.1603/me11217] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The aim of the study was to evaluate rickettsial infection in ticks from wild birds of the Semidecidual and Atlantic Rainforest remnants of three municipalities of the State of Paraná, southern Brazil. Overall, 53 larvae and nymphs collected from birds were checked for the presence of Rickettsia DNA by molecular tests. Five tick species were tested: Amblyomma aureolatum (Pallas), Amblyomma calcaratum Neumann, Amblyomma longirostre (Koch), Amblyomma ovale Koch, and Amblyomma parkeri Fonseca and Aragão. A. longirostre ticks were infected with the spotted fever group agents Rickettsia amblyommii strain AL (32.3% infection rate) and Rickettsia parkeri strain NOD (5.9% infection rate). A new rickettsial genotype was detected in the tick A. parkeri (50% infection rate), which had never been reported to be infected by rickettsiae. Through phylogenetic analysis, this new genotype, here designated as strain ApPR, grouped in a cluster composed by different strains of Rickettsia africae, Rickettsia sibirica, and R. parkeri. We consider strain ApPR to be a new genotype of R. parkeri. This study reports for the first time rickettsial infection in ticks from birds in southern Brazil. The role of migrating birds in the dispersal of these rickettsial strains should be considered in ecological studies of spotted fever group agents in Brazil.
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Affiliation(s)
- Richard C Pacheco
- Faculty of Agronomy and Veterinary Medicine, Federal University of Mato Grosso, Cuiabá, MT, Brazil.
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Melo ALT, Martins TF, Horta MC, Moraes-Filho J, Pacheco RC, Labruna MB, Aguiar DM. Seroprevalence and risk factors to Ehrlichia spp. and Rickettsia spp. in dogs from the Pantanal Region of Mato Grosso State, Brazil. Ticks Tick Borne Dis 2011; 2:213-8. [PMID: 22108015 DOI: 10.1016/j.ttbdis.2011.09.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 07/27/2011] [Accepted: 09/08/2011] [Indexed: 11/18/2022]
Abstract
Sera of 320 dogs from urban and rural areas of a Pantanal region of Brazil were evaluated for rickettsial (Rickettsia rickettsii, R. parkeri, R. amblyommii, R. rhipicephali, R. felis, and R. bellii) and ehrlichial (Ehrlichia canis) infection by the immunofluorescence assay (IFA). Risk factors for ehrlichiosis or rickettsiosis were also evaluated. Positive reaction against Ehrlichia spp. was detected in 227 (70.9%) dogs, 119 (74.3%) from an urban area and 108 (67.5%) from rural areas (P>0.05). For Rickettsia spp., 152 (47.5%) dogs were positive, 31 (19.3%) from urban and 121 (75.6%) from rural areas (P<0.05). Highest anti-Rickettsia spp. endpoint titers were observed for R. amblyommii, suggesting homologous reactions to this agent or a very closely related organism. While most of the urban dogs were found parasitized by the tick Rhipicephalus sanguineus, infestations on rural dogs were predominated by Amblyomma cajenennse. Rickettsial infection was significantly higher (P<0.05) in rural dogs, in dogs with hunting practice, or in A. cajennense-infested dogs.
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Affiliation(s)
- Andréia L T Melo
- Faculdade de Agronomia, Medicina Veterinária e Zootecnia da Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil
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Batista FG, Silva DMD, Green KT, Tezza LBDL, Vasconcelos SPD, Carvalho SGSD, Silveira I, Moraes-Filho J, Labruna MB, Fortes FS, Molento MB. Serological survey of Rickettsia sp. in horses and dogs in a non-endemic area in Brazil. ACTA ACUST UNITED AC 2011; 19:205-9. [PMID: 21184695 DOI: 10.1590/s1984-29612010000400003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Accepted: 09/23/2010] [Indexed: 11/22/2022]
Abstract
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 animals. All farmers completed a questionnaire about their knowledge of BSF and animal health management. Serum samples were analyzed by indirect immunofluorescent-antibody assay (IFA) using R. rickettsii and R. parkeri as antigens. Ticks were analyzed by PCR for Rickettsia sp., and all of them were PCR-negative. Six horses (8.45%) and 4 dogs (20%) were identified as seropositive. Farmers were not aware of the correlation between the presence of ticks and risk of BSF. Although a non-endemic area, Almirante Tamandaré is a vulnerable environment for BSF and effective tick control measures are required.
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Affiliation(s)
- Fernanda Gonçalves Batista
- Laboratory of Parasitic Diseases, Federal University of Paraná, Rua dos Funcionários 1540, Curitiba-PR, Brazil
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Fortes FS, Silveira I, Moraes-Filho J, Leite RV, Bonacim JE, Biondo AW, Labruna MB, Molento MB. Seroprevalence of Rickettsia bellii and Rickettsia felis in dogs, São José dos Pinhais, State of Paraná, Brazil. ACTA ACUST UNITED AC 2011; 19:222-7. [PMID: 21184698 DOI: 10.1590/s1984-29612010000400006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Accepted: 11/05/2010] [Indexed: 11/22/2022]
Abstract
Brazilian spotted fever (BSF) is a vector-borne zoonosis caused by Rickettsia rickettsii bacteria. Dogs can be host sentinels for this bacterium. The aim of the study was to determine the presence of antibodies against Rickettsia spp. in dogs from the city of São José dos Pinhais, State of Paraná, Southern Brazil, where a human case of BSF was first reported in the state. Between February 2006 and July 2007, serum samples from 364 dogs were collected and tested at 1:64 dilutions by indirect immunofluorescence assay (IFA) against R. rickettsii and R. parkeri. All sera that reacted at least to one of Rickettsia species were tested against the six main Rickettsia species identified in Brazil: R. rickettsii, R. parkeri, R. bellii, R. rhipicephali, R. amblyommii and R. felis. Sixteen samples (4.4%) reacted to at least one Rickettsia species. Among positive animals, two dogs (15.5%) showed suggestive titers for R. bellii exposure. One sample had a homologous reaction to R. felis, a confirmed human pathogen. Although Rickettsia spp. circulation in dogs in the area studied may be considered at low prevalence, suggesting low risk of human infection, the present data demonstrate for the first time the exposure of dogs to R. bellii and R. felis in Southern Brazil.
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Affiliation(s)
- Fernanda Silva Fortes
- Laboratório de Doenças Parasitárias, Departamento de Medicina Veterinária, Faculdade de Medicina Veterinária, Universidade Federal do Paraná, Rua dos Funcionários 1540, Curitiba-PR, Brazil
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Pacheco RC, Moraes-Filho J, Guedes E, Silveira I, Richtzenhain LJ, Leite RC, Labruna MB. Rickettsial infections of dogs, horses and ticks in Juiz de Fora, southeastern Brazil, and isolation of Rickettsia rickettsii from Rhipicephalus sanguineus ticks. Med Vet Entomol 2011; 25:148-155. [PMID: 20950356 DOI: 10.1111/j.1365-2915.2010.00915.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
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. rickettsii were successfully established in Vero cell culture from two Rh. sanguineus ticks. An indirect immunofluorescence assay (IFA) using R. rickettsii antigens detected blood serological reaction to R. rickettsii in 67.9% (53/78) of dogs and 41.0% (16/39) of horses living in the study area. Larval offspring from two Rh. sanguineus engorged females, naturally infected by R. rickettsii, were reared to adult stage in the laboratory. All active stages (larvae, nymphs, adults) remained 100% infected by R. rickettsii, which was efficiently transmitted to naïve rabbits. Overall, the results of the present study indicate a potential risk for transmission of R. rickettsii to humans by Rh. sanguineus, an occurrence yet to be documented in Brazil.
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Affiliation(s)
- R C Pacheco
- Department of Basic Sciences and Animal Production, Faculty of Veterinary Medicine, Federal University of Mato Grosso, Cuiabá, MT, Brazil
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Labruna MB, Ogrzewalska M, Soares JF, Martins TF, Soares HS, Moraes-Filho J, Nieri-Bastos FA, Almeida AP, Pinter A. Experimental infection of Amblyomma aureolatum ticks with Rickettsia rickettsii. Emerg Infect Dis 2011; 17:829-34. [PMID: 21529391 PMCID: PMC3321777 DOI: 10.3201/eid1705.101524] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
We experimentally infected Amblyomma aureolatum ticks with the bacterium Rickettsia rickettsii, the etiologic agent of Rocky Mountain spotted fever (RMSF). These ticks are a vector for RMSF in Brazil. R. rickettsii was efficiently conserved by both transstadial maintenance and vertical (transovarial) transmission to 100% of the ticks through 4 laboratory generations. However, lower reproductive performance and survival of infected females was attributed to R. rickettsii infection. Therefore, because of the high susceptibility of A. aureolatum ticks to R. rickettsii infection, the deleterious effect that the bacterium causes in these ticks may contribute to the low infection rates (<1%) usually reported among field populations of A. aureolatum ticks in RMSF-endemic areas of Brazil. Because the number of infected ticks would gradually decrease after each generation, it seems unlikely that A. aureolatum ticks could sustain R. rickettsii infection over multiple successive generations solely by vertical transmission.
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Affiliation(s)
- Marcelo B Labruna
- Faculty of Veterinary Medicine, University of São Paulo, São Paulo, Brazil.
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Freitas MCDDO, Grycajuk M, Molento MB, Bonacin J, Labruna MB, Pacheco RDC, Moraes-Filho J, Deconto I, Biondo AW. Brazilian spotted fever in cart horses in a non-endemic area in Southern Brazil. ACTA ACUST UNITED AC 2011; 19:130-1. [PMID: 20624353 DOI: 10.4322/rbpv.01902012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2010] [Accepted: 02/09/2010] [Indexed: 11/23/2022]
Abstract
Brazilian Spotted Fever (BSF) is an often fatal zoonosis caused by the obligate intracellular bacterium Rickettsia rickettsii. The disease is generally transmitted to humans by Amblyomma spp. ticks. Serological evidence of past infection by R. rickettsii has been reported in horses, but the pathogenicity of R. rickettsii in horses remains unknown. Cart horses are still widely used in urban and urban fringe areas in Brazil, and these animals may constitute suitable sentinels for BSF human in these areas, for example, in Sao Jose dos Pinhais, where the first BSF human case in the state of Parana was diagnosed. Serum samples were randomly obtained from 75 cart horses between April 2005 and June 2006 and were tested by means of the indirect immunofluorescence assay (IFA) for antibodies against rickettsia of the spotted fever group. A total of 9.33% of the animals were considered positive, with titers ranging from 64 to 1,024. These results indicate the presence of the agent in such areas, although at low rates.
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Affiliation(s)
- Marta Cristina Diniz de Oliveira Freitas
- Laboratório de Doenças Parasitárias, Departamento de Medicina Veterinária, Setor de Ciências Agrárias, Faculdade de Medicina Veterinária e Zootecnia, Universidade Federal do Paraná - UFPR, Rua dos Funcionários, 1540, Curitiba - PR, Brazil.
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Bermúdez CSE, Zaldívar AY, Spolidorio MG, Moraes-Filho J, Miranda RJ, Caballero CM, Mendoza Y, Labruna MB. Rickettsial infection in domestic mammals and their ectoparasites in El Valle de Antón, Coclé, Panamá. Vet Parasitol 2011; 177:134-8. [DOI: 10.1016/j.vetpar.2010.11.020] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 11/08/2010] [Accepted: 11/10/2010] [Indexed: 10/18/2022]
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Moraes-Filho J, Marcili A, Nieri-Bastos FA, Richtzenhain LJ, Labruna MB. Genetic analysis of ticks belonging to the Rhipicephalus sanguineus group in Latin America. Acta Trop 2011; 117:51-5. [PMID: 20858451 DOI: 10.1016/j.actatropica.2010.09.006] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Revised: 09/10/2010] [Accepted: 09/14/2010] [Indexed: 10/19/2022]
Abstract
Phylogenetic analyses based on mitochondrial 16S rDNA sequences were generated from Rhipicephalus sanguineus group specimens collected in 29 localities among 9 Latin-American countries, plus ticks collected in South Africa, Spain, and Italy. Sequences from Latin America generated six different haplotypes (A, B, C, D, E, and F). Phylogenetic analyses generated trees that segregated our tick sequences into two distinct clades: one is represented by haplotypes A-C, and South African R. sanguineus and Rhipicephalus turanicus ticks; the second clade is represented by haplotypes D-F, and European R. sanguineus and R. turanicus ticks. When haplotypes A-F are plotted in the Latin America map according to their geographical coordinates, it is clearly seen that haplotypes D-F are restricted to the southern portion of this continent, whereas haplotypes A-C are distributed in areas between northern Mexico and Brazil (except for the extreme south of this last country, where haplotype E was present). Hence, our phylogenetic analyses separated New World specimens of R. sanguineus into two distinct clades, one represented by tropical and subtropical populations (haplotypes A-C), here designated as the 'tropical' species. On the other hand, haplotypes D-F are here designated as the 'temperate' species because of their distribution in the southern portion of South America. Until recently, it was assumed that the R. sanguineus group was represented by a single species in the New World, namely R. sanguineus. While the present results coupled with recent studies support the presence of at least two species under the taxon R. sanguineus in the New World, they also show that even in the Old World, the taxon R. sanguineus might be represented by more than one species, since our phylogenetic analysis segregated European and South African R. sanguineus ticks into two distinct clades. The same can be applied for Spanish and South African R. turanicus.
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Spolidorio MG, Labruna MB, Machado RZ, Moraes-Filho J, Zago AM, Donatele DM, Pinheiro SR, Silveira I, Caliari KM, Yoshinari NH. Survey for tick-borne zoonoses in the state of Espirito Santo, southeastern Brazil. Am J Trop Med Hyg 2010; 83:201-6. [PMID: 20595502 DOI: 10.4269/ajtmh.2010.09-0595] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Blood samples collected from 201 humans, 92 dogs, and 27 horses in the state of Espirito Santo, Brazil, were tested by polymerase chain reaction, indirect immunofluorescence assays, and indirect enzyme-linked immunosorbent assay for tick-borne diseases (rickettsiosis, ehrlichiosis, anaplasmosis, borreliosis, babesiosis). Our results indicated that the surveyed counties are endemic for spotted fever group rickettsiosis because sera from 70 (34.8%) humans, 7 (7.6%) dogs, and 7 (25.9%) horses were reactive to at least one of the six Rickettsia species tested. Although there was evidence of ehrlichiosis (Ehrlichia canis) and babesiosis (Babesia canis vogeli, Theileria equi) in domestic animals, no human was positive for babesiosis and only four individuals were serologically positive for E. canis. Borrelia burgdorferi-serologic reactive sera were rare among humans and horses, but encompassed 51% of the canine samples, suggesting that dogs and their ticks can be part of the epidemiological cycle of the causative agent of the Brazilian zoonosis, named Baggio-Yoshinari Syndrome.
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Affiliation(s)
- Mariana G Spolidorio
- Laboratório de Investigação Médica 17 (LIM17), Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil.
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Silva M, Ribeiro R, Costa J, Moraes-Filho J, Pacheco R, Labruna M. Prevalência de anticorpos anti-Rickettsia spp. em cães da cidade de Belo Horizonte, MG. ARQ BRAS MED VET ZOO 2010. [DOI: 10.1590/s0102-09352010000400036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Freitas MCDDO, Grycajuk M, Molento MB, Bonacin J, Labruna MB, Pacheco RDC, Moraes-Filho J, Deconto I, Biondo AW. Brazilian spotted fever in cart horses in a non-endemic area in Southern Brazil. Rev Bras Parasitol Vet (Online) 2010. [DOI: 10.1590/s1984-29612010000200013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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Horta MC, Sabatini GS, Moraes-Filho J, Ogrzewalska M, Canal RB, Pacheco RC, Martins TF, Matushima ER, Labruna MB. Experimental infection of the opossum Didelphis aurita by Rickettsia felis, Rickettsia bellii, and Rickettsia parkeri and evaluation of the transmission of the infection to ticks Amblyomma cajennense and Amblyomma dubitatum. Vector Borne Zoonotic Dis 2010; 10:959-67. [PMID: 20455783 DOI: 10.1089/vbz.2009.0149] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This work evaluated the infection of opossums (Didelphis aurita) by Rickettsia felis, Rickettsia bellii, and Rickettsia parkeri and their role as amplifier hosts for horizontal transmission to Amblyomma cajennense and/or Amblyomma dubitatum ticks. Infection in D. aurita was induced by intraperitoneal inoculation with R. felis (n = 4 opossums), R. bellii (n = 4), and R. parkeri (n = 2). Another group of six opossums were inoculated intraperitoneally with Leibovitz-15 sterile culture medium, representing the uninfected groups (n = 2 opossums simultaneously to each infected group). Opossum blood samples collected during the study were used for DNA extraction, followed by real-time polymerase chain reaction targeting the rickettsial gene gltA, hematology, and detection of Rickettsia spp.-reactive antibodies by indirect immunofluorescence assay. Opossums were infested with uninfected A. cajennense and/or A. dubitatum for 30 days postinoculation (DPI). Flat ticks molted from ticks fed on opossums were allowed to feed on uninfected rabbits, which were tested for seroconversion by immunofluorescence assay. Samples of flat ticks were also tested by real-time polymerase chain reaction. Inoculated opossums showed no clinical abnormalities. Antibodies to Rickettsia spp. were first detected at the second to fourth DPI, with detectable titers until the 150th DPI. Rickettsemia was detected only in one opossum inoculated with R. parkeri, at the eighth DPI. Only one A. cajennense tick (2.0%) previously fed on a R. parkeri-inoculated opossum became infected. None of the rabbits infested with opossum-derived ticks seroconverted. The study demonstrated that R. felis, R. bellii, and R. parkeri were capable to produce antibody response in opossums, however, with undetectable rickettsemia for R. felis and R. bellii, and very low rickettsemia for R. parkeri. Further studies must be done with different strains of these rickettsiae, most importantly the strains that have never gone through in vitro passages.
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Affiliation(s)
- Maurício C Horta
- Colegiado de Medicina Veterinária, Campus de Ciências Agrárias, Universidade Federal do Vale do São Francisco, Petrolina, Brasil.
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Conti-Díaz IA, Moraes-Filho J, Pacheco RC, Labruna MB. Serological evidence of Rickettsia parkeri as the etiological agent of rickettsiosis in Uruguay. Rev Inst Med Trop Sao Paulo 2009; 51:337-9. [DOI: 10.1590/s0036-46652009000600005] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Accepted: 10/27/2009] [Indexed: 11/21/2022] Open
Abstract
We report three new rickettsiosis human cases in Uruguay. The three clinical cases presented clinical manifestations similar to previous reported cases of Rickettsia parkeri in the United States; that is mild fever (< 40 ºC), malaise, headache, rash, inoculation eschar at the tick bite site, regional lymphadenopathy, and no lethality. Serological antibody-absorption tests with purified antigens of R. parkeri and Rickettsia rickettsii, associated with immunofluorescence assay indicated that the patients in two cases were infected by R. parkeri. Epidemiological and clinical evidences, coupled with our serological analysis, suggest that R. parkeri is the etiological agent of human cases of spotted fever in Uruguay, a disease that has been recognized in that country as cutaneous-ganglionar rickettsiosis.
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Abstract
Clinical illness caused by Rickettsia rickettsii in dogs has been reported solely in the United States. We report 2 natural clinical cases of Rocky Mountain spotted fever in dogs in Brazil. Each case was confirmed by seroconversion and molecular analysis and resolved after doxycycline therapy.
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Affiliation(s)
- Marcelo B Labruna
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, University of São Paulo, São Paulo, Brazil.
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Pacheco RC, Horta MC, Pinter A, Moraes-Filho J, Martins TF, Nardi MS, Souza SSALD, Souza CED, Szabó MPJ, Richtzenhain LJ, Labruna MB. Pesquisa de Rickettsia spp em carrapatos Amblyomma cajennense e Amblyomma dubitatum no Estado de São Paulo. Rev Soc Bras Med Trop 2009; 42:351-3. [DOI: 10.1590/s0037-86822009000300023] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Accepted: 04/29/2009] [Indexed: 11/21/2022] Open
Abstract
Foi pesquisada a presença de riquétsias em 3.545 carrapatos Amblyomma cajennense e 2.666 Amblyomma dubitatum. Através do teste de hemolinfa, reação em cadeia pela polimerase e isolamento de rickettsia em cultivo celular, todos os Amblyomma cajennense foram negativos, sendo que 634 (23,8%) Amblyomma dubitatum mostraram-se infectados com Rickettsia bellii.
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Moraes-Filho J, Horta MC, Pacheco RDC, Maeda MM, Galano A, Oliveira MLD, Yai LEO, Labruna MB. Pesquisa de anticorpos anti-Rickettsia rickettsii em eqüinos do Centro de Controle de Zoonoses do município de São Paulo (CCZ/SP). Braz J Vet Res Anim Sci 2009. [DOI: 10.11606/issn.1678-4456.bjvras.2009.26753] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A Febre Maculosa Brasileira (FMB) é uma zoonose transmitida por pelo menos duas espécies de carrapatos: Amblyomma cajennense e Amblyomma aureolatum. Os eqüinos assumem um importante papel de sentinela da FMB em áreas onde o carrapato vetor é o A. cajennense, por ser considerado hospedeiro primário dessa espécie de carrapato. O A. aureolatum, cujos hospedeiros primários são aves, alguns roedores silvestres e canídeos, é incriminado como vetor da doença na região da Grande São Paulo. Este trabalho objetivou pesquisar a presença de anticorpos contra Rickettsia rickettsii, agente da FMB, em eqüinos encaminhados ao Centro de Controle de Zoonoses do município de São Paulo (CCZ/SP) no período de 2003 a 2005. Após coleta de sangue, o soro obtido pela centrifugação foi submetido à reação de imunofluorescência indireta (RIFI) e os animais foram considerados positivos quando as amostras de soro apresentaram títulos >; 64. Durante os três anos, foram testados 363 amostras pela RIFI, sendo que 64 se mostraram reagentes: 6 (2003), 16 (2004) e 42 (2005). Os títulos finais variaram de 64 a 1.024. Os resultados obtidos demonstram uma baixa porcentagem de animais reagentes (17,6%) quando comparados com dados de literatura de áreas endêmicas para FMB onde o vetor é o A. cajennense, sugerindo não ser essa espécie responsável pela transmissão da doença na área de estudo
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Horta MC, Moraes-Filho J, Casagrande RA, Saito TB, Rosa SC, Ogrzewalska M, Matushima ER, Labruna MB. Experimental infection of opossums Didelphis aurita by Rickettsia rickettsii and evaluation of the transmission of the infection to ticks Amblyomma cajennense. Vector Borne Zoonotic Dis 2008; 9:109-18. [PMID: 18945194 DOI: 10.1089/vbz.2008.0114] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The present study evaluated the infection of opossums (Didelphis aurita) by Rickettsia rickettsii and their role as amplifier hosts for horizontal transmission of R. rickettsii to Amblyomma cajennense ticks. Three groups of opossums were evaluated: on day 0, group 1 (G1) was inoculated intraperitoneally with R. rickettsii; group 2 (G2) was infested by R. rickettsii-infected ticks; and group 3 (G3) was the uninfected control group. Opossum rectal temperature was measured daily. Blood samples were collected every 2 to 4 days during 30 days, and used to (1) inoculate guinea pigs intraperitoneally; (2) extract DNA followed by real-time polymerase chain reaction (PCR) targeting the rickettsial gene gltA; (3) study hematology; (4) detect R. rickettsii-reactive antibodies by indirect immunofluorescence assay (IFA). Blood was also collected every 10 days from days 30 to 180, to be tested by serology. Opossums were infested by uninfected A. cajennense larvae and nymphs from days 3 to 15. Engorged ticks were collected and allowed to molt in an incubator. Thereafter, the subsequent flat ticks were allowed to feed on uninfected rabbits, which were tested for seroconversion by IFA. Samples of flat ticks were also tested by real-time PCR. All G1 and G2 opossums became infected by R. rickettsii, as demonstrated by realtime PCR or/and guinea pig inoculation, but they showed no clinical abnormality. Rickettsemia was first detected at days 2 to 8, lasting intermittently till days 1 to 30. Approximately 18% and 5% of the flat ticks previously fed on G1 and G2 opossums, respectively, became infected by R. rickettsii, but only the rabbits infested with G1-derived ticks seroconverted. The study demonstrated that R. rickettsii was capable of infecting opossums without causing illness and developing rickettsemia capable of causing infection in guinea pigs and ticks, although the infection rate in ticks was low.
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Affiliation(s)
- Maurício C Horta
- Departamento de Medicina Veterinária Preventiva e Saúde Animal, Universidade de São Paulo, São Paulo, Brasil.
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