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Rickettsial infection in capybaras (Hydrochoerus hydrochaeris) from S?o Paulo, Brazil: serological evidence for infection by Rickettsia bellii and Rickettsia parkeri
Pacheco,Richard C; Horta,Mauricio C; Moraes-Filho,Jonas; Ataliba,Alexandre C; Pinter,Adriano; Labruna,Marcelo B;
Biomédica , 2007,
Abstract: introduction. in brazil, capybaras (hydrochoerus hydrochaeris) are important hosts for amblyomma ticks, which in turn can transmit rickettsiae to humans and animals. therefore, capybaras are potential sentinels for rickettsial infection. objective. the present study evaluated rickettsial infection in capybaras in different areas of the state of s?o paulo, where rickettsiosis has never been reported. materials and methods. blood sera from 73 capybaras from six localities in s?o paulo were tested by indirect immunofluorescence assay using rickettsia rickettsii, rickettsia parkeri, and rickettsia bellii antigens. capybara spleens were tested by pcr, targeting a fragment of the rickettsial glta gene. ticks were collected from each capybara sample and taxonomically identified to species. results. a total of 94 positively reacting capybara samples, 19 (26.0%), 25 (34.2%), and 50 (68.5%) capybara sera reacted to r. rickettsii, r. parkeri, and r. bellii, respectively. twenty-five capybara sera showed titers to r. bellii at least four-fold higher than to any of the other two antigens. these sera were considered homologous to r. bellii. using the same criteria, 3 capybara sera were considered homologous to r. parkeri. no sera were be considered homologous to r. rickettsii. no rickettsial dna was detected in capybara spleen samples. ticks collected on capybaras were amblyomma dubitatum and amblyomma cajennense. conclusions. the first evidence is reported of r. bellii natural infection in vertebrate hosts, and the first evidence of r. parkeri infection in capybaras. while r. parkeri is known to infect and cause disease in humans, no similar evidence for human infection has been indicated by r. bellii.
Anti-Rickettsia spp. antibodies in free-ranging and captive capybaras from southern Brazil
Fortes, Fernanda S.;Santos, Leonilda C.;Cubas, Zalmir S.;Barros-Filho, Ivan R.;Biondo, Alexander W.;Silveira, Iara;Labruna, Marcelo B.;Molento, Marcelo B.;
Pesquisa Veterinária Brasileira , 2011, DOI: 10.1590/S0100-736X2011001100013
Abstract: capybaras (hydrochaeris hydrochaeris) are among the main hosts of amblyomma spp. ticks, which is able to transmit rickettsia species to human beings and animals. since they are often infested with potential vector ticks, capybaras may be used as sentinels for rickettsiosis, such as the brazilian spotted fever. the aim of the present study was to determine the prevalence of antibodies against rickettsia spp. using the indirect immunofluorescence assay (ifa) in 21 free-ranging and 10 captive animals from the zoological park of the 'bela vista biological sanctuary' (bvbs), itaipu binational, foz do igua?u, southern brazil. antigens of six rickettsial species already identified in brazil (rickettsia rickettsii, r. parkeri, r. bellii, r. rhipicephali, r. amblyommii and r. felis) were used for ifa. ticks from each capybara were collected for posterior taxonomic identification. a total of 19 (61.3%) samples reacted to at least one of tested species. seropositivity was found in 14 (45.2%), 12 (38.7%), 5 (16.1%), 4 (12.9%), 3 (9.7%) and 3 (9.7%) animals for r. rickettsii, r. bellii, r. parkeri, r. amblyommii, r. felis and r. rhipicephali, respectively. two captive capybaras presented suggestive titers of r. rickettsii infection and one sample showed homologous reaction to r. parkeri. only one free-ranging capybara presented evidence r. bellii infection. ticks collected on capybaras were identified as amblyomma dubitatum e amblyomma sp. results evidenced the rickettsial circulation in the area, suggesting a potential role of capybaras on bacterial life cycle.
Surveillance of Rickettsia sp. infection in capybaras (Hydrochoerus hydrochaeris) a potential model of epidemiological alert in endemic areas Vigilancia de la infección por Rickettsia sp. en capibaras (Hydrochoerus hydrochaeris) un modelo potencial de alerta epidemiológica en zonas endémicas  [cached]
Jorge Miranda,Verónica Contreras,Yesica Negrete,Marcelo B. Labruna
Biomédica , 2011,
Abstract: Introduction. Capybaras (Hydrochoerus hydrochaeris) are considered amplifying hosts of Rickettsia sp. These rodents are usually parasitized by the tick vector, Amblyomma cajennense, the main vector of rickettsioses in humans and animals in South America. Capybaras can be used as sentinels in detection of circulation of rickettsiae. Objective. Antibodies to rickettsiae of spotted fever group were detected in capybaras in a rural area of Cordoba Province, northern Colombia. Materials and methods. Sera were analyzed from 36 capybaras in a rural area of Monteria (village of San Jeronimo) in Córdoba. For the detection of IgG antibodies, indirect immunofluorescence was performed. The antigens were derived from R. rickettsia strain Taia u isolated in Brazil. Capybara sera were diluted 1:64 for IFA analysis. Ticks were collected from each capybara (also known as chigüiro) and identified to species. Results. The seroprevalence of spotted fever group Rickettsia was 22% (8 capybaras). Four sera had a titer of 1:64, 3 had a titer of 1:128 and one serum had a titer of 1:512. All ticks removed from the capybaras (n=933) were taxonomically identified as Amblyomma cajennense. Conclusion. Colombia has areas endemic for rickettsioses, as indicated by confirmed annual outbreaks. The current study reports the first evidence of natural rickettsial infection of the spotted fever group in capybaras from Colombia. The findings suggest that capybaras can be used as sentinels for the circulation of rickettsiae and can identify endemic areas for the transmission of rickettsial diseases. Introducción. Los capibaras o chigüiros (Hydrochoerus hydrochaeris) son huéspedes amplificadores de Rickettsia sp. Usualmente se encuentran parasitados por la garrapata Amblyomma cajennense, principal vector de rickettsiosis en Suramérica. Los capibaras pueden ser usados como potenciales centinelas de la circulación de rickettsias. Objetivo. Detectar anticuerpos contra Rickettsia sp. del grupo de las fiebres manchadas en capibaras de una zona rural del municipio de Montería, departamento de Córdoba. Material y métodos. Se analizaron 36 sueros de capibaras de una zona rural de Montería (vereda San Jerónimo) en Córdoba. Para la detección de anticuerpos IgG se practicó inmunofluorescencia indirecta, que utilizó antígenos de la cepa Taia u de Rickettsia rickettsii de Brasil. Los sueros de los capibaras fueron diluidos 1:64. Se capturaron las garrapatas que se encontraban parasitando los capibaras y se clasificaron hasta su especie. Resultados. La seroprevalencia contra Rickettsia sp. del grupo de la fi
Vigilancia de la infección por Rickettsia sp. en capibaras (Hydrochoerus hydrochaeris) un modelo potencial de alerta epidemiológica en zonas endémicas
Miranda,Jorge; Contreras,Verónica; Negrete,Yésica; Labruna,Marcelo B; Máttar,Salim;
Biomédica , 2011,
Abstract: introduction. capybaras (hydrochoerus hydrochaeris) are considered amplifying hosts of rickettsia sp. these rodents are usually parasitized by the tick vector, amblyomma cajennense, the main vector of rickettsioses in humans and animals in south america. capybaras can be used as sentinels in detection of circulation of rickettsiae. objective. antibodies to rickettsiae of spotted fever group were detected in capybaras in a rural area of cordoba province, northern colombia. materials and methods. sera were analyzed from 36 capybaras in a rural area of monteria (village of san jeronimo) in córdoba. for the detection of igg antibodies, indirect immunofluorescence was performed. the antigens were derived from r. rickettsia strain taia?u isolated in brazil. capybara sera were diluted 1:64 for ifa analysis. ticks were collected from each capybara (also known as chigüiro) and identified to species. results. the seroprevalence of spotted fever group rickettsia was 22% (8 capybaras). four sera had a titer of 1:64, 3 had a titer of 1:128 and one serum had a titer of 1:512. all ticks removed from the capybaras (n=933) were taxonomically identified as amblyomma cajennense. conclusion. colombia has areas endemic for rickettsioses, as indicated by confirmed annual outbreaks. the current study reports the first evidence of natural rickettsial infection of the spotted fever group in capybaras from colombia. the findings suggest that capybaras can be used as sentinels for the circulation of rickettsiae and can identify endemic areas for the transmission of rickettsial diseases.
Seroprevalence of Rickettsia bellii and Rickettsia felis in dogs, S?o José dos Pinhais, State of Paraná, Brazil
Fortes, Fernanda Silva;Silveira, Iara;Moraes-Filho, Jonas;Leite, Ronaldo Viana;Bonacim, José Edivaldo;Biondo, Alexander Welker;Labruna, Marcelo Bahia;Molento, Marcelo Beltr?o;
Revista Brasileira de Parasitologia Veterinária , 2010, DOI: 10.1590/S1984-29612010000400006
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 s?o 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.
Serological evidence of Rickettsia parkeri as the etiological agent of rickettsiosis in Uruguay
Conti-Díaz, Ismael A.;Moraes-Filho, Jonas;Pacheco, Richard C.;Labruna, Marcelo B.;
Revista do Instituto de Medicina Tropical de S?o Paulo , 2009, DOI: 10.1590/S0036-46652009000600005
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.
Intestinal helminths of capybaras, Hydrochoerus hydrochaeris, from Venezuela
Salas, Viviana;Herrera, Emilio A;
Memórias do Instituto Oswaldo Cruz , 2004, DOI: 10.1590/S0074-02762004000600004
Abstract: quantitative parameters of intestinal helminth species and their potential relations to host characteristics in a population of capybaras (hydrochoerus hydrochaeris) from venezuela are reported for the first time. the intestines of 40 capybaras were collected during the 1992-annual harvest at hato el cedral. six helminth species were found: 2 cestodes (monoecocestus macrobursatum, m. hagmanni), 2 nematodes (viannella hydrochoeri, protozoophaga obesa), and 2 trematodes (hippocrepis hippocrepis, taxorchis schistocotyle). this is the first report for m. macrobursatum in venezuela. helminth abundance did not differ between sexes or age classes. although patterns of distribution for all helminth species were overdispersed, the high prevalence found for all species (over 70%) and the high abundance observed for nematodes made it difficult to assess the effect that these helminths may produce on capybaras. nevertheless, the negative associations found between the body condition of capybaras and helminth intensity for m. macrobursatum and v. hydrochoeri, might be pointing out potential host population regulatory role for these parasites which require further research.
Rickettsia infection in five areas of the state of S?o Paulo, Brazil
Horta, Maurício C;Labruna, Marcelo B;Pinter, Adriano;Linardi, Pedro M;Schumaker, Teresinha T S;
Memórias do Instituto Oswaldo Cruz , 2007, DOI: 10.1590/S0074-02762007000700003
Abstract: this study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of s?o paulo. eight flea species (adoratopsylla antiquorum antiquorum, ctenocephalides felis felis, polygenis atopus, polygenis rimatus, polygenis roberti roberti, polygenis tripus, rhopalopsyllus lugubris, and rhopalopsyllus lutzi lutzi), and five tick species (amblyomma aureolatum, amblyomma cajennense, amblyomma dubitatum, ixodes loricatus, and rhipicephalus sanguineus) were collected from dogs, cats, and opossums. rickettsia felis was the only rickettsia found infecting fleas, whereas rickettsia bellii was the only agent infecting ticks, but no animal or human blood was shown to contain rickettsial dna. testing animal and human sera by indirect immunofluorescence assay against four rickettsia antigens (r. rickettsii, r. parkeri, r. felis, and r. bellii), some opossum, dog, horse, and human sera reacted to r. rickettsii with titers at least four-fold higher than to the other three rickettsial antigens. these sera were considered to have a predominant antibody response to r. rickettsii. using the same criteria, opossum, dog, and horse sera showed predominant antibody response to r. parkeri or a very closely related genotype. our serological results suggest that both r. rickettsii and r. parkeri infected animals and/or humans in the studied areas.
Effect of ascorbic acid on food preference and consumption in captive capybaras (Hydrochoerus hydrochaeris)
Alvarez, Martín Roberto;Kravetz, Fernando Osvaldo;
Brazilian Archives of Biology and Technology , 2009, DOI: 10.1590/S1516-89132009000300011
Abstract: the aim of this work was to study the short and long term influences of ascorbic acid on hydrochoerus hydrochaeris, if supplemented in their food. no differences regarding food intake were observed in the absence of vitamin c. on a daily basis, animals accustomed to food containing ascorbic acid prefered to continue eating the same food. food preference in capybaras did not seem to depend on ascorbic acid availability; however, when accustomed to vitamin c, capybaras might recognize and select ascorbic acid in subsequent food. mechanisms allowing capybaras to "evaluate" the nutritional quality of their food are discussed, as well as the adaptive value of this behavior in free ranging populations.
Study of colpo-cytological at the capybaras (Hydrochoerus hydrochaeris) Caracteriza o da colpocitologia em capivaras ("Hydrochoerus hydrochaeris")
Larissa Pires Barbosa,Marcos Vinícius Rodrigues,Mariana Machado Neves,Danielle Barbosa Morais
Revista Brasileira de Saúde e Produ??o Animal , 2007,
Abstract: Capybara (Hydrochoerus hydrochaeris) is one of the species which has interested farmers due to its performance potential, as a result of the quality of its skin and meat. Based on commercial interests, many studies have been done to understand the reproductive physiology and to answer questions that could help to improve the productive status of these animals. This study was performed to describe the cell types from the vaginal epithelium of capybaras and to compare the efficiency of three dyes on cell staining. The experiment was carried out at Centro de Biodiversidade of USIPA, in Ipatinga/MG. Cells were obtained by the swab technique from five adult animals and stained with Giemsa, Methylene Blue and Shorr. Samples were collected every three and five days, during 30 days. Four types of cells were observed, parabasal cells, intermediate cells and superficial cells (with or without nucleus), besides bacteria and leukocytes. The three dyes were able to stain efficiently on colpocitology, however, Giemsa and Metileno Blue were more practical than Shorr. Colpocytology was shown to be an applicable procedure for this animal species. A capivara (Hydrochoerus hydrochaeris) é uma das espécies que tem despertado o interesse de produtores rurais pelo potencial zootécnico, advindo da qualidade do seu couro e da sua carne. Com base no interesse comercial, muitas pesquisas têm sido desenvolvidas para se entender a fisiologia reprodutiva e responder quest es que possam ajudar no aumento da produ o desses animais em cativeiro. Este estudo foi conduzido com o objetivo de descrever as células do epitélio vaginal de capivaras e comparar a eficiência de três corantes na colora o das mesmas. O experimento foi realizado no Centro de Biodiversidade da USIPA em Ipatinga / MG. As células foram obtidas pela técnica de swab vaginal de cinco fêmeas adultas cativas e coradas com: Giemsa, Azul de Metileno e Shorr. Foram realizadas coletas com intervalos de 3 e 5 dias, durante um período de 30 dias. Foram encontrados quatro tipos celulares, as células parabasais, células intermediárias e células superficiais (nucleadas e anucleadas), além de células bacterianas e leucócitos. Os três corantes agiram de forma eficiente nas células da colpocitologia, contudo os corantes Giemsa e Azul de Metileno apresentaram maior praticidade, em rela o ao corante Shorr. A colpocitologia mostrou-se uma técnica aplicável nessa espécie.
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