Diversity of rickettsiae in ticks (Acari: Ixodidae) collected from wild vertebrates in part of the Amazon, Cerrado, and Pantanal biomes in Brazil.

Ticks parasitizing 102 wild animals in the states of Mato Grosso and Goiás, Brazil were collected between 2015 and 2018. A total of 2338 ticks (865 males, 541 females, 823 nymphs, and 109 larvae) belonging to four genera (Amblyomma, Dermacentor, Haemaphysalis, and Rhipicephalus) and at least 21 species were identified. DNA extraction and a molecular survey for rickettsial agents were performed on 650 ticks. The results revealed parasitism by the following species: Rickettsia amblyommatis in Amblyomma cajennense s.s., A. cajennense s.l., Amblyomma coelebs, Amblyomma humerale, Amblyomma longirostre, Amblyomma nodosum, Amblyomma scalpturatum, Amblyomma sculptum, and Amblyomma romitii; Rickettsia parkeri in Amblyomma nodosum, Amblyomma ovale, Amblyomma scalpturatum, and Amblyomma triste; Rickettsia rhipicephali in Haemaphysalis juxtakochi; Rickettsia sp. in A. cajennense s.s., A. nodosum, and A. sculptum, and lastly, 'Candidatus Rickettsia andeanae' in Amblyomma parvum and Rhipicephalus microplus. This study expands the body of knowledge about tick parasitism among wild animals, including new data concerning tick-host associations, and provides information about the epidemiology of tick-borne pathogens in the Center-West region of Brazil.

Serological Evidence Supporting the Occurrence of Ehrlichia chaffeensis or a Closely Related Species in Brazilian Dogs.

Ehrlichia chaffeensis is a tick-borne bacterium that causes human monocytotropic ehrlichiosis, an emerging life-threatening disease in humans transmitted by Amblyomma americanum. Although most studies have reported bacterial isolations and clinical cases in the United States, their occurrence is not restricted to North America. Some studies in the Southern Cone of South America have molecularly detected a close phylogenetic relative of E. chaffeensis in ticks and wild mammals. Even so, many gaps must be filled to confirm the presence of this agent in the region. To add new data on this issue, we report the first detection of specific anti-E. chaffeensis antibodies in dogs collected from all regions of Brazil. By means of IFA and ELISA with crude and specific antigens of E. chaffeensis, sera from 1134 dogs were analyzed. Serological analyses using ELISA showed nine (0.7%) seropositive dogs, with seven of them exhibiting IFA titers ranging from 160 to 5120. All regions of Brazil had at least one seropositive dog. Our results support the evidence for the occurrence of E. chaffeensis in South America. As dogs have a close relationship with humans, they can be used as an environmental sentinel for these infections because they can act as a bridge to human parasitism or infection with ehrlichial agents.

Pleural effusion-related Nocardia otitidiscaviarum, Anaplasma platys and Ehrlichia canis coinfection in a dog.

The coinfections by some microorganisms have been related to severe diseases in humans and animals, where immunosuppressive agents favor opportunistic behavior of other pathogens. A 4-month-old, female mixed-breed dog with a two-week history of inappetence, prostration, emaciation, and respiratory distress was admitted at a veterinary hospital in Brazil. Tachycardia, pale mucous membranes, severe respiratory distress, and a large number of ticks (Rhipicephalus sanguineus s.l.) in different body regions were observed at clinical examination. Hematological examination of dog showed leukocytosis, neutrophilia, mild anemia, and thrombocytopenia, whereas unremarkable values in biochemical tests. Thoracic radiography revealed a pleural effusion image. Blood and the pleural fluid (purulent aspect) samples were subjected to qPCR (16S rRNA and dsb genes) and sequencing, which identified Ehrlichia canis and Anaplasma platys coinfection. An aggregate of coccoid-to-branching or long filamentous microorganisms, surrounded by pyogranulomatous inflammatory reaction was seen at the cytology of the pleural fluid. Bacteriological culture of pleural effusion showed colonies compatible with the genus Nocardia, which revealed gram-positive filamentous organisms with a tendency of fragmentation and were identified as Nocardia otitidiscaviarum in mass spectrometry (MALDI-TOF MS). Therapy of N. otitidiscaviarum isolate using levofloxacin (supported by a previous in vitro susceptibility testing) and doxycycline for E. canis and A. platys resulted in complete resolution of the clinical picture. Here, we report for the first time a triple coinfection by Nocardia otitidiscaviarum, A. platys, and E. canis in a dog with pleural effusion, where debilitating or immunosuppressive conditions induced by A. platys and E. canis coinfection probably contributed to the opportunistic behavior of N. otitidiscaviarum.

Costa Rican Genotype of Ehrlichia canis: A Current Concern.

Canine monocytic ehrlichiosis (CME) is endemic to Brazil, and studies have verified that dogs have been exposed to different genotypes of Ehrlichia canis. This genetic divergence can influence the clinical response of the animals. We aimed to describe clinical and hematological changes in 125 dogs that reacted to BrTRP36, USTRP36, and CRTRP36 genotypes through enzyme immunoassays and to highlight the current concern regarding infection by the Costa Rican genotype. The results showed that 52.0% reacted to the Brazilian genotype, 22.4% reacted to the Costa Rican genotype, and 16.0% reacted to the American genotype, and some co-reactions were observed. Dogs reactive to BrTRP36 were 1.24% more likely to present with medullary regeneration in cases of anemia and 3% less likely to manifest hyperproteinemia, while dogs reactive to CRTRP36 were 0.7% less likely to present with medullary regeneration. Febrile illness and neurological alterations were also statistically associated, with an 85.7% and 231.2% increased likelihood, respectively, to occur in dogs that reacted to USTRP36. The dogs with the American genotype developed clinical manifestations related to systemic inflammation, while those with the Brazilian genotype of E. canis were more dispersed in the region studied, showing greater adaptation to the hosts. We highlight the significant serocurrence of the Costa Rican genotype, which has already been described to have zoonotic potential and which showed less adaptation.

Molecular detection and genetic characterization of Ehrlichia canis and Ehrlichia sp. in neotropical primates from Brazil.

The Anaplasmataceae family includes obligate, arthropod-transmitted intracellular bacteria that can be zoonotic and potentially fatal. Studies focusing on the interaction between neotropical primates and the agents of this family are scarce. The present study aimed to identify agents of the Anaplasmataceae family in the whole blood of free-living and captive neotropical primates in the State of Mato Grosso, Central-West Brazil. Thirty-eight samples of six nonhuman primate (NHP) species were collected in seven municipalities and analysed through polymerase chain reaction (PCR), nucleotide sequencing, and phylogenetic analysis of the dsb, groEL, 16S rRNA, and gltA genes. DNA fragments similar to those of Ehrlichia canis were detected in Sapajus apella and Ehrlichia chaffeensis from Mico melanurus. The sequences generated in this study and homologous sequences retrieved from GenBank® were used for phylogenetic analyses to characterize the Ehrlichial agents detected in NHPs. The agents were then grouped into clades corresponding to different isolates from the NHP species. In addition, an Anaplasma sp. closely related to Anaplasma marginale was identified in two S. apella individuals. These findings shed light on the susceptibility of neotropical NHPs to Anaplasmataceae agents. These bacteria are known to be transmitted by ticks, which can also serve as possible sources of infection for other animals, including humans.

Toxoplasma gondii exposure in felines: an alarming factor to public health from mineiros, Goiás / Exposição ao toxoplasma gondii em felinos: um fator alarmante para a saúde pública de Mineiros, Goiás / Exposición a toxoplasma gondii en felinos: un factor alarmante para la salud pública de Mineiros, Goiás

Toxoplasmosis is a cosmopolitan disease caused by Toxoplasma gondii, an obligate protozoan that affects endothermic animals, including man. Being a zoonosis that can cause abortions, fetal malformations and blindness. Cats are the definitive hosts, acting as a source of dissemination. In order to collect epidemiological data on the distribution of T. gondii in Mineiros, Goiás, samples of domestic cats were analyzed to verify the circulation of the protozoan and reinforce preventive measures. Ninety-four samples of domestic cats, regardless of gender, age and breed, were randomly processed in the neighborhoods of Mineiros, Goiás. They were submitted to the indirect fluorescent antibody test for antibodies against T. gondii, using tachyzoites as antigens and anti-cat IgG conjugate (1:16 were positive). Of the 94 samples analyzed, 35 (37.2%) were reagents, of which four had a titration of 1:16, ten of 1:32, eleven of 1:64, eight of 1:128 and two of 1:256. All cats were semi-domiciled, but lifestyle and diet were not assessed. T. gondii infection is rarely symptomatic and the severity depends on the pathophysiological state. Brazil has high prevalence rates and requires effective care in the management of cats. In Mineiros, 29 reports of infected pregnant women were identified. Although infection in humans occurs primarily through consumption of undercooked meat, ingestion of oocysts in feces of cats is a possibility. Therefore, state public health institutions and veterinarians should promote health education, highlighting food hygiene. Since, when symptomatic, the disease presents severe clinical conditions and, in some cases, irreversible.

A toxoplasmose é uma doença cosmopolita causada pelo Toxoplasma gondii, um protozoário obrigatório que afeta animais endotérmicos, incluindo o homem. Sendo uma zoonose que pode causar abortos, malformações fetais e cegueira. Os gatos são os hospedeiros definitivos, atuando como fonte de disseminação. Para coletar dados epidemiológicos sobre a distribuição do T. gondii em Mineiros, Goiás, amostras de gatos domésticos foram analisadas para verificar a circulação do protozoário e reforçar as medidas preventivas. Noventa e quatro amostras de gatos domésticos, independente de sexo, idade e raça, foram processadas aleatoriamente nos bairros de Mineiros, Goiás. Foram submetidos ao teste de anticorpo fluorescente indireto para pesquisa de anticorpos contra T. gondii, utilizando como antígenos taquizoítos e conjugado anti-cat IgG (1:16 foram positivos). Das 94 amostras analisadas, 35 (37,2%) eram reagentes, das quais quatro tiveram titulação de 1:16, dez de 1:32, onze de 1:64, oito de 1:128 e duas de 1:256. Todos os gatos eram semi-domiciliados, mas o estilo de vida e a dieta não foram avaliados. A infecção por T. gondii raramente é sintomática e a gravidade depende do estado fisiopatológico. O Brasil possui altas taxas de prevalência e requer cuidados efetivos no manejo dos gatos. Em Mineiros, foram identificadas 29 notificações de gestantes infectadas. Embora a infecção em humanos ocorra principalmente pelo consumo de carne mal cozida, a ingestão de oocistos nas fezes de gatos é uma possibilidade. Portanto, as instituições estaduais de saúde pública e os médicos veterinários devem promover a educação em saúde, destacando a higiene alimentar. Já que, quando sintomática, a doença apresenta quadros clínicos graves e, em alguns casos, irreversíveis.

La toxoplasmosis es una enfermedad cosmopolita causada por Toxoplasma gondii, un protozoario obligado que afecta a animales endotérmicos, incluido el hombre. Ser una zoonosis que puede provocar abortos, malformaciones fetales y ceguera. Los gatos son los huéspedes definitivos, actuando como fuente de diseminación. Con el fin de recolectar datos epidemiológicos sobre la distribución de T. gondii en Mineiros, Goiás, se analizaron muestras de gatos domésticos para verificar la circulación del protozoario y reforzar las medidas preventivas. Noventa y cuatro muestras de gatos domésticos, independientemente de género, edad y raza, fueron procesadas al azar en los barrios de Mineiros, Goiás. Se sometieron a la prueba de anticuerpos fluorescentes indirectos contra T. gondii, utilizando como antígenos taquizoítos e IgG anti-cat conjugada (1:16 fueron positivos). De las 94 muestras analizadas, 35 (37,2%) fueron reactivos, de los cuales cuatro tuvieron una titulación de 1:16, diez de 1:32, once de 1:64, ocho de 1:128 y dos de 1:256. Todos los gatos tenían domicilio parcial, pero no se evaluó el estilo de vida ni la dieta. La infección por T. gondii rara vez es sintomática y la gravedad depende del estado fisiopatológico. Brasil tiene altas tasas de prevalencia y requiere una atención eficaz en el manejo de los gatos. En Mineiros se identificaron 29 casos de mujeres embarazadas infectadas. Aunque la infección en los seres humanos se produce principalmente a través del consumo de carne poco cocida, la ingestión de ovoquistes en las heces de los gatos es una posibilidad. Por lo tanto, las instituciones estatales de salud pública y los veterinarios deben promover la educación sanitaria, destacando la higiene alimentaria. Dado que, cuando sintomática, la enfermedad presenta cuadros clínicos severos y, en algunos casos, irreversibles.

Epidemiological aspects of the occurrence of anti-Sarcocystis spp. andanti-Toxoplasma gondii antibodies in dogs in the Northern region of Brazil / Aspectos epidemiológicos da ocorrência de anticorpos anti-Sarcocystisspp. e anti-Toxoplasma gondii em cães da região norte do Brasil

We conducted aseroepidemiological study on the occurrence of anti-Sarcocystisspp. and anti-Toxoplasma gondii antibodies in dogs from family farming properties in the municipality of Ji-Paraná, Rondônia.Blood samples were collected from apparently healthy dogs between September 2012 and November 2013. In total, 181 blood serum samples were analyzed using an indirect immunofluorescence assay, among which 57 (31.49%) and 20 (11.04%) were positive for anti-T. gondii and anti-Sarcocystis spp., respectively. Statistical analyses showed that the type of food fed to the dogs was associated with the occurrence of anti-Sarcocystisspp. antibodies. In contrast, age and access to bovine carcasses were the risk factors for anti-T. gondii.The high occurrence of seropositive dogs for Sarcocystis spp. and T. gondii evidences the wide distribution of these agents in the studied area, possibly due to human and animal exposure to these protozoan species. In addition, anti-T. gondii antibodies were directly proportional to dog age. The increase in the number of positive animals with age was statistically significant. Furthermore, high antibody titers (up to 800) against Sarcocystis spp. in dogs suggest the possibility of recent exposure, in addition to environmental contamination by oocysts/sporocysts eliminated by the feces of these animals.

Conduzimos um estudo soroepidemiológico sobre a ocorrência de anticorpos anti- Sarcocystis spp. e anti-Toxoplasma gondiiem cães de propriedades de agricultura familiar no município de Ji-Paraná, Rondônia. Amostras de sangue foram coletadas de cães aparentemente saudáveis, entre setembro de 2012 e novembro de 2013. Ao todo, foram analisados 181 soros sanguíneos por meio do ensaio de imunofluorescência indireta, sendo positivas 57 (31,49%) e 20 (11,04%) amostras para anticorpos anti-T. gondii e anti-Sarcocystis spp., respectivamente. As análises estatísticas demonstraram que o tipo de alimentação fornecida aos cães esteve associado à ocorrência de anticorpos anti-Sarcocystis spp. Em contraste a idade e o acesso à carcaça bovina foram fatores de risco para a presença de anticorpos anti-T. gondii. A alta ocorrência de cães soropositivos para Sarcocystis spp. e T. gondii evidencia a ampla distribuição desses agentes na área estudada, possivelmente devido à exposição humana e animal a essas espécies de protozoários. Além disso, o resultado dos anticorpos anti-T. gondii relacionados a idade do cão mostraram diferença estatística, com aumento significativo no número de animais positivos com a idade. Além disso, altos títulos de anticorpos (até 800) contra Sarcocystis spp. em cães sugerem a possibilidade de exposição recente, além da contaminação ambiental por oocistos/esporocistos eliminados pelas fezes desses animais.

Novel Ehrlichia canis genogroup in dogs with canine ehrlichiosis in Cuba.

BACKGROUND: Canine monocytic ehrlichiosis (CME) is caused by the tick-borne pathogen Ehrlichia canis, an obligate intracellular Gram-negative bacterium of the family Anaplasmataceae with tropism for canine monocytes and macrophages. The trp36 gene, which encodes for the major immunoreactive protein TRP36 in E. canis, has been successfully used to characterize the genetic diversity of this pathogen in different regions of the world. Based on trp36 sequence analysis, four E. canis genogroups, United States (US), Taiwan (TWN), Brazil (BR) and Costa Rica (CR), have been identified. The aim of this study was to characterize the genetic diversity of E. canis in Cuba based on the trp36 gene. METHODS: Whole blood samples (n = 8) were collected from dogs found to be infested with the tick vector Rhipicephalus sanguineus sensu lato (s.l.) and/or presenting clinical signs and symptoms of CME. Total DNA was extracted from the blood samples and trp36 fragments were amplified by PCR. Nucleotide and protein sequences were compared using alignments and phylogenetic analysis. RESULTS: Four of the trp36 sequences obtained (n = 8) fall within the phylogenetic cluster grouping the US genogroup E. canis strains. The other E. canis trp36 sequences formed a separate and well-supported clade (94% bootstrap value) that is phylogenetically distant from the other major groups and thus represents a new genogroup, herein designated as the 'Cuba (CUB) genogroup'. Notably, dogs infected with the CUB genogroup presented frequent hemorrhagic lesions. CONCLUSIONS: The results of this study suggest that genetic diversification of E. canis in Cuba is associated with the emergence of E. canis strains with increased virulence.

Canine gastrointestinal pythiosis: a case report in Brazilian Pantanal from a diagnostic approach / Pitiose gastrointestinal canina: relato de caso no Pantanal brasileiro a partir de uma abordagem diagnóstica

Pythiosis is caused by an aquatic fungus-like organism (Pythium insidiosum). It is considered an important public health issue as it can affect both animals and humans. This paper reports a case of gastrointestinal pythiosis in a dog. The patient was hospitalized for four days, during which the animal received supportive and symptomatic treatment. But the applied treatment was unsuccessful and the dog's clinical condition worsened, culminating in death. Complementary imaging tests such as radiography and ultrasonography, as well as hematological tests, were performed during the hospitalization period. The definitive diagnosis was reached in the postmortem as macroscopic and microscopic characteristics suggested the presence of intestinal granuloma and accentuated multifocal suppurative necrotic enteritis. Additionally, the histological evaluation revealed morphological structures compatible with P. insidiosum. Also, the results of nested PCR performed showed partial amplification (105 bp) of the ITS1 region of the ribosomal gene of P. insidiosum.(AU)

A pitiose é causada por um organismo aquático semelhante a um fungo (Pythium insidiosum) e considerada um importante problema de saúde pública, pois pode afetar animais e humanos. Este artigo relata um caso de pitiose gastrointestinal em um cão. O paciente ficou internado por quatro dias, período em que o animal recebeu tratamento de suporte e sintomático. No entanto, o tratamento aplicado não teve sucesso e o quadro clínico do cão piorou, culminando com a morte. Exames de imagem complementares, como radiografia e ultrassonografia, bem como exames hematológicos, foram realizados durante o período de internação. O diagnóstico definitivo foi feito na autópsia, pois as características macroscópicas e microscópicas sugeriam a presença de granuloma intestinal e acentuada enterite necrótica multifocal supurativa. Além disso, a avaliação histológica revelou estruturas morfológicas compatíveis com P. insidiosum. Além disso, a nested PCR foi realizada e mostrou amplificação parcial (105 pb) da região ITS1 do gene ribossomal de P. insidiosum.(AU)

First report on the isolation and genotyping of Toxoplasma gondii strains from free-range chickens in the state of Mato Grosso, Midwestern Brazil.

In the present study, 51 strains of Toxoplasma gondii (T. gondii) were isolated from free-range chickens in the state of Mato Grosso, Midwestern Brazil, upon conducting bioassays in mice, and genotyped them using PCR-restriction fragment length polymorphism (PCR-RFLP) and 11 markers, including SAG1, SAG2 (5'3'SAG2 and alt. SAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico, and CS3. Fifty isolates were completely genotyped revealing 17 genotypes of T. gondii as follows: 12 matched using ToxoDB PCR-RFLP with the previously reported genotypes, including #6 type BrI (n = 4), #8 type BrIII (n = 7), #11 type BrII (n = 3), #14 (n = 1), #19 (n = 1), #41 (n = 1), #99 (n = 1), #109 (n = 4), #116 (n = 1), #140 (n = 2), #166 (n = 9), #190 (n = 1); and five genotypes have not been described before [#313 (n = 6), #314 (n = 1), #315 (n = 1), #316 (n = 1), #317 (n = 1)]. Moreover, mixed infections were identified in five isolates (TgCkBrMT8, TgCkBrMT9, TgCkBrMT33, TgCkBrMT38, and TgCkBrMT41). Additionally, genotype #190 was reported for the first time in chickens from Brazil. Our results corroborate with previous studies on T. gondii isolates identified in chickens from Brazil, thereby confirming their diversity, a typicality, and possibility of co-infection due to different T. gondii strains present in the country.

Concentrations of tissue inhibitor of matrix metalloproteinase-1 and hyaluronic acid in canine amniotic membranes cryopreserved for different time points and its effects in dogs with complicated corneal ulcers.

OBJECTIVES: To determine the concentrations of total protein (TP), tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and hyaluronic acid (HA) in amniotic membranes (AMs) harvested from placentas of bitches of different ages and cryopreserved for different time points. The outcomes of complicated corneal defects of dogs repaired with AMs stored for the same time points were also evaluated. PROCEDURES: Ten cryopreserved canine AMs were stored for short term (2-50 days), middle term (92-210 days), or long term (256-357 days). TP was quantified by Bradford's test, whereas TIMP-1 and HA were quantified by ELISA. Twenty-one dogs that had an AM transplantation to restore deep or perforating corneal wounds were selected. RESULTS: TIMP-1 levels were lower in AMs cryopreserved for middle term (p = .02) and long term (p = .0009), when compared to AMs stored for short term. TP (p = .39) and HA (p = .18) concentrations in AMs did not differ among the storage time. TIMP-1 concentration in AMs correlated with storage time (R = -.65, p < .0001), while TP (R = -.33, p = .07) and HA concentrations did not (R = -.15, p = .41). The age of donors did not correlate with the components evaluated in the AMs. Corneal defects repaired with AMs stored for short term healed sooner than the ones repaired with AMs stored for middle (p < .01) and long term (p = .02). Additionally, TIMP-1 levels in AMs correlated negatively with the epithelization time (R = -.62, p = .002). Graft opacity was severe in 55% of cases. However, the HA levels in AMs correlated negatively with the opacification score (R = -.47, p = .03). Vision was observed in more patients who presented deep ulcers and descemetoceles, than in the ones with perforations (p = .004). CONCLUSIONS: TIMP-1 concentration in canine AMs significantly decreased over a year storage time, while TP and HA concentrations did not change during the same period. The age of donors did not correlate with the components evaluated in the AMs. Complicated corneal defects repaired with AMs cryopreserved for short term healed sooner and tended to be less opaque; however, satisfactory to optimal outcomes were achieved even in the eyes repaired with AMs stored for up to a year.

Ocorrência de Babesia sp, Ehrlichia canis e Hepatozoon canis em cães domiciliados, em dois municípios do estado do Espírito Santo - Brasil / Occurrence of Babesia sp, Ehrlichia canis and Hepatozoon canis in domiciled dogs in two municipalities of the state of Espírito Santo - Brazil / Ocurrencia de Babesia sp, Ehrlichia canis y Hepatozoon canis em perros domiciliados em dos municipios del estado de Espírito Santo - Brasil

As doenças transmitidas por carrapatos são afecções de grande importância na clínica médica de pequenos animais, devido à alta casuística e ampla distribuição vetorial no território brasileiro. Os principais agentes responsáveis pelas infecções em cães são Babesia sp., Ehrlichia canis e Hepatozoon canis. Os animais infectados são assintomáticos ou apresentam sinais clínicos inespecíficos, sendo necessário a utilização de testes diagnósticos para definição do agente etiológico, e diagnóstico seguro. O objetivo do presente estudo foi determinar a ocorrência desses micro-organismos em cães naturalmente infectados, domiciliados nos municípios de Vila Velha e Anchieta, Espírito Santo, utilizando diferentes testes de detecção: Reação em cadeia polimerase (PCR), sorologia para detecção de anticorpos anti Ehrlichia canis e pesquisa de hematozoários em esfregaço sanguíneo. Foram analisadas 65 amostras de sangue obtidas por venopunção de veia cefálica de cães. No teste de PCR, 4,62% dos animais foram positivos para Babesia vogeli e 1,54% para Ehrlichia canis sendo os resultados para Hepatozoon canis negativos. No teste sorológico para E. canis 90,77% dos animais foram positivos para a presença de anticorpos, e na pesquisa em lâminas de esfregaço sanguíneo 3,02% apresentavam outros hemoparasitas. Os resultados indicam a dispersão desses hemoparasitas na população canina da região de estudo, entretanto com baixa ocorrência. O teste de PCR demonstrou-se como o mais sensível no qual Babesia vogeli foi o agente mais observado.(AU)

Tick-borne diseases are diseases of great importance in the medical practice of small animals, due to the high casuistry and wide vectorial distribution in the Brazilian territory. The main agents responsible for infections in dogs are Babesia sp., Ehrlichia canis and Hepatozoon canis. Infected animals are asymptomatic or present nonspecific clinical signs, requiring the use of diagnostic tests to define the etiologic agent, and safe diagnosis. The objective of the present study was to determine the occurrence of these microorganisms in naturally infected dogs domiciled in the municipalities of Vila Velha and Anchieta, Espírito Santo, using different detection tests: polymerase chain reaction (PCR), serology to detect antibodies against Ehrlichia canis and research of hematozoa in blood smears. Sixty-five blood samples obtained by venipuncture of the cephalic vein of dogs were analyzed. In the PCR test, 4.62% of the animals were positive for Babesia vogeli and 1.54% for Ehrlichia canis, and the results for Hepatozoon canis were negative. In the serological test for E. canis, 90.77% of the animals were positive for the presence of antibodies, and in the research in blood smear slides, 3.02% presented other hemoparasites. The results indicate the dispersion of these hemoparasites in the canine population of the study region, however with low occurrence. The PCR test proved to be the most sensitive, in which Babesia vogeli was the most observed agent.(AU)

Las enfermedades transmitidas por garrapatas son enfermedades de gran importancia en la práctica médica de los pequeños animales, debido a la alta casuística y amplia distribución vectorial en el territorio brasileño. Los principales agentes responsables de las infecciones en los perros son Babesia sp., Ehrlichia canis y Hepatozoon canis. Los animales infectados son asintomáticos o presentan signos clínicos inespecíficos, siendo necesario el uso de pruebas diagnósticas para la definición del agente etiológico, y el diagnóstico seguro. El objetivo del presente estudio fue determinar la ocurrencia de estos microorganismos en perros infectados naturalmente, domiciliados en los municipios de Vila Velha y Anchieta, Espírito Santo, utilizando diferentes pruebas de detección: reacción en cadena de la polimerasa (PCR), serología para detectar anticuerpos anti Ehrlichia canis e investigación de hematozoos en frotis de sangre. Se analizaron sesenta y cinco muestras de sangre obtenidas por venopunción de la vena cefálica de los perros. En la prueba PCR, el 4,62% de los animales fueron positivos para Babesia vogeli y el 1,54% para Ehrlichia canis, y los resultados para Hepatozoon canis fueron negativos. En la prueba serológica para E. canis, el 90,77% de los animales fueron positivos a la presencia de anticuerpos, y en la investigación en láminas de frotis de sangre el 3,02% presentaron otros hemoparásitos. Los resultados indican la dispersión de estos hemoparásitos en la población canina de la región de estudio, aunque con una baja presencia. La prueba PCR resultó ser la más sensible, en la que Babesia vogeli fue el agente más observado.(AU)

Seroprevalence and hematological abnormalities associated with Ehrlichia canis in dogs referred to a veterinary teaching hospital in central-western Brazil / Soroprevalência e alterações hematológicas associadas com Ehrlichia canis em cães encaminhados a um hospital veterinário-escola no centro-oeste do Brasil

Ticks are significant parasites of dogs in the tropics, where tick-borne pathogens are highly prevalent, especially in areas where tick control measures are frequently neglected. This study investigated the seroprevalence and hematological abnormalities associated with Ehrlichia canis in dogs referred to a veterinary teaching hospital in Central-western Brazil. Out of 264 dogs tested for anti-Ehrlichia canis antibodies by an indirect immunofluorescence assay (IFA), 59.1% (156/264) were positive. Seropositivity was significantly associated to anemia and thrombocytopenia, alone or in combination, and to leukopenia. Conversely, there were no differences in terms of seroprevalence according to sex, breed and age. This study demonstrated that dogs referred to a veterinary teaching hospital in Central-western Brazil are highly exposed to E. canis and that seropositive dogs are more likely to present hematological abnormalities, particularly anemia, thrombocytopenia and leukopenia. To our knowledge, this is the first study on detection of anti-E. canis antibodies by means of IFA among dogs in the state of Goiás. These findings highlighted the need for increasing awareness among dog owners regarding tick control measures in Central-western Brazil, ultimately to reduce the risk of exposure to E. canis and other tick-borne pathogens.

Carrapatos são importantes parasitos de cães nos trópicos, onde patógenos transmitidos por carrapatos são altamente prevalentes, especialmente em áreas onde as medidas de controle de carrapatos são frequentemente negligenciadas. O estudo investigou a soroprevalência e as anormalidades hematológicas associadas à Ehrlichia canis em cães encaminhados para um hospital veterinário-escola no Centro-oeste do Brasil. Dos 264 cães testados para anticorpos anti-Ehrlichia canis por meio da reação de imunofluorescência indireta (RIFI), 59.1% (156/264) foram positivos. A soropositividade foi associada significativamente à anemia e trombocitopenia, isoladamente ou em combinação, e à leucopenia. Por outro lado, não houve diferenças quanto à soroprevalência segundo sexo, raça e idade. Este estudo demonstrou que cães encaminhados a um hospital veterinário-escola na região Centro-oeste do Brasil são altamente expostos à E. canis, e que cães soropositivos têm maior probabilidade de apresentar alterações hematológicas, principalmente anemia, trombocitopenia e leucopenia. Para o nosso conhecimento, este é o primeiro estudo sobre a detecção de anticorpos anti-E. canis por meio da RIFI em cães do estado de Goiás. Essas descobertas destacam a necessidade de aumentar a conscientização entre os proprietários de cães em relação às medidas de controle do carrapato no Centro-oeste do Brasil, em última análise, para reduzir o risco de exposição ao E. canis e outros patógenos transmitidos por carrapatos.

Exposure of Domestic Cats to Distinct Ehrlichia canis TRP Genotypes.

Cats naturally exposed to Ehrlichia canis have been described in different regions of the world, but little is known about the genotypes associated with infection in these animals. To detect E. canis-specific antibodies and investigate the E. canis TRP genotypes in cats, serum samples from 76 domestic cats reactive to crude E. canis antigens by the indirect fluorescence antibody test (IFAT) were analyzed by ELISA, using E. canis-specific peptides (i.e., TRP19 and TRP36 /BR/US/CR). Of these, 25 (32.9%) cats reacted to at least one TRP peptide, confirming their specific exposure to E. canis. Eighteen (23.7%) cats reacted to TRP19, 15 (19.8%) to BRTRP36, and 11 (14.5%) to USTRP36, but none of them reacted to CRTRP36. Eight (10.5%) cats reacted to TRP19 but not to any TRP36 genotype, demonstrating the possible existence of a new E. canis genotype infecting felines. Nevertheless, this study provides the first report of anti-E. canis-specific antibodies in domestic cats.

Seroprevalence and risk factors of Toxoplasma gondii in cattle from Unai, Minas Gerais state, Brazil.

Toxoplasma gondii is a widespread protozoan parasite that causes infections in animals and humans. The presence of tissue cysts in cattle musculature evidences their epidemiological significance in transmission to humans. The present study aimed to evaluate the seroprevalence of and risk factors of T. gondii seropositivity in beef cattle in the municipality of Unaí, Minas Gerais state, Brazil. Bovine blood samples (n = 612) were collected from 31 herds. Risk factors associated with the animal-level and herd-level seroprevalence were analysed using a questionnaire that investigates the epidemiological aspects of toxoplasmosis. A search for anti-T. gondii antibodies was performed by means of an indirect fluorescent antibody test (IFAT). Analysis of 612 samples showed 369 animals positive for anti-T. gondii antibodies (IFAT ≥64), with a seroprevalence of 60.29% (95% confidence interval (CI): 56.35-64.10). The herd-level seroprevalence was 96.77% (95% CI: 79.00-99.58). Applying a multivariate logistic regression analysis, a test of the association between seroprevalence of T. gondii infection and the potential predictors showed that cats (domestic or wild) with access to the drinking water of cattle were a significant (P = 0.001) predictor. The seroprevalence of T. gondii in cattle destined for human consumption is widely distributed throughout the entire study area. Thus, integrated control measures and strategies are suggested to prevent T. gondii infection in cattle.

High prevalence of anti-Toxoplasma gondii antibodies in beef cattle in Midwestern Brazil.

The present study aimed to determine the seroprevalence of anti-Toxoplasma gondii antibodies using an indirect immunofluorescence assay (IFA-IgG) in 3,814 cows aged ≥ 24 months belonging to 353 beef farms in the Mato Grosso state. Additionally, we aimed to identify the possible risk factors associated with seropositivity in Mato Grosso, which encompasses three biomes (Amazon, Cerrado, and Pantanal) of Brazil. Analysis of 3,814 samples observed that 1,307 animals were positive for anti-T. gondii antibodies (IFA-IgG ≥ 64), with an animal-level seroprevalence of 34.27%. Herd-level seroprevalence was 92.07%. In the animal-level model, cows raised in the Amazon and Pantanal biomes and breed studies on European and Zebu or hybrid were found to be at risk for T. gondii seropositivity. Prevalence of anti-T. gondii antibodies in cows destined for human consumption was found to be widely distributed throughout the entire study area. Further studies are required to assess the impact of beef in the possible transmission of toxoplasmosis to humans residing in the region and establish additional control measures for this protozoan mainly on beef herds raised in the Amazon and Pantanal biomes, where the highest values of seroprevalence were observed.

Serological evidence of Ehrlichia minasensis infection in Brazilian dogs.

Ehrlichia spp. are important tick-borne pathogens of animals in Brazil, and Ehrlichia canis is the most prevalent species infecting dogs. Moreover, Ehrlichia minasensis has also recently been identified as a novel ehrlichial agent that infects cattle in Brazil. The objective of this study was to determine whether dogs could be infected by E. minasensis. To investigate this possibility, sera (n = 429) collected from dogs in the Pantanal region were retrospectively analyzed for the presence of antibodies against E. canis and E. minasensis. Canine sera were screened by two isolates of E. canis in indirect immunofluorescence assay (IFA) and the majority (n = 298; 69.4%) had antibodies with endpoint titers ranging from 80 to 327,680. In order to further confirm E. canis-specific antibodies, IFA positive sera were analyzed by ELISA using E. canis-specific peptides (i.e. TRP19 and TRP36 US/BR/CR), which detected E. canis antibodies in 80.2% (239/298) of the dog sera. Fifty-nine (13.7%) samples had detectable antibodies to E. canis by IFA but were negative by E. canis peptide ELISA. These sera were then tested by E. minasensis IFA (Cuiaba strain) as antigen and 67.8% (40/59) were positive (titers ranging from 80 to 20,480). Eleven sera had antibody titers against E. minasensis at least two-fold higher than observed for E. canis and suggests that these dogs were previously infected with E. minasensis. The results of the present study suggest that multiple ehrlichial agents infect dogs in Brazil, which highlights the need to consider different Ehrlichia spp. in Brazilian dogs, particularly in areas where dogs are frequently exposed to multiple tick species. This investigation is the first to provide serologic evidence of E. minasensis infection in dogs from Brazil.

Risk factor analysis associated with Neospora caninum in dairy cattle in Western Brazilian Amazon.

Neospora caninum is considered to be one of the main causes of abortion among cattle. The present survey was conducted in the municipality of Rolim de Moura, Rondônia State, Brazil. A questionnaire that investigates the epidemiological aspects of neosporosis was used in the analysis of risk factors associated with the animal-level and herd-level prevalence in dairy cattle. A total of 416 bovine blood samples were collected from 30 farms, and N. caninum antibody levels were measured by Indirect Fluorescent Antibody Test (IFAT). Analysis of dairy cattle serum samples revealed the presence of anti-N. caninum antibodies to be 47.36% (n = 197). Risk factors associated with N. caninum infection were the management system and access locations of dogs. The results of the present survey indicated that infection of dairy cattle with N. caninum is widespread in the studied region of Western Amazon, which has implications for prevention and control of neosporosis in this region. Therefore, integrated control strategies and measures are recommended to prevent and control N. caninum infection in dairy cattle. In addition, direct contact between dairy cattle, dogs and wild animals, which can influence the epidemiology of neosporosis, should be investigated further.

Detection of Ehrlichia sp. in Amblyomma sculptum parasitizing horses from Brazilian Pantanal wetland.

Bacteria of the genus Ehrlichia are transmitted by ticks and also are an important cause of infection in wild and domestic mammals. Infection with Ehrlichia spp. has been reported in horses, especially in the USA, Nicaragua and Brazil. In this study, we report the parasitism by Amblyomma sculptum, Rhipicephalus microplus and Dermacentor nitens ticks in horses from a ranch located in south Pantanal wetland. Molecular and serological analyzes to determine infection by Ehrlichia spp. in horses and their respective ticks were carried out. A total of 12 horses were submitted to blood collection to investigate antibodies by indirect immunofluorescence assay (IFA) using Ehrlichia canis crude antigens and to be tested by polymerase chain reaction (PCR) in order to amplify fragments of the 16S rRNA, dsb, groEL and sodB gene of Ehrlichia spp. A total of 164 tick specimens were removed from horses, stored in isopropanol and later identified as D. nitens, A. sculptum and R. microplus. DNA from ticks were extracted and subjected to the same PCR assays to detect Ehrlichia spp. Anti-Ehrlichia spp. antibodies were detected in five/12 (41.7 %) horses by IFA, with antibody titers ranging from 40 to 160. All horse DNA samples were negative for the 16S rRNA, dsb, groEL and sodB of Ehrlichia spp. One A. sculptum female was positive to all target genes of Ehrlichia. This tick was parasitizing an Ehrlichia-seropositive horse with antibody titer of 80. Nucleotide sequences of 16S rRNA, dsb, groEL and sodB genes showed close relationship with different strains of Ehrlichia detected in wild mammals, Amblyomma ticks and horses from Brazil and Argentina. Detection of anti-Ehrlichia sp. antibodies suggests that horses have been exposed to an ehrlichial agent in the Pantanal. Future studies on Ehrlichia infection should be carried out to better elucidate and to bring new information about equine ehrlichiosis, since these animals are important hosts of ticks in the Brazilian Pantanal wetlands.

Seroprevalence of Toxoplasma gondii and Neospora caninum in sheep intended for human consumption in the Rondônia state, Western Brazilian Amazon.

The aim of this study was to carry out a seroepidemiological study of anti-T. gondii and anti-N. caninum antibodies in serum samples from sheep intended for human consumption in the Rondônia state, in the Western Brazilian Amazon, and identify possible risk factors associated with seropositivity. The analysis of the 616 sheep serum samples revealed animal-level seroprevalence of T. gondii in the order of 52.4 % and of N. caninum of 60.6 %. Prevalence of co-infections was 33.4 %. The herd-level seroprevalence was 100 % for both the parasites. Applying of multivariate logistic regression analysis, test of the association between seroprevalence of T. gondii infection and the potential predictors showed that feed, fetal malformation, abortion, neurological problems (lambs), presence of rodents were the significant (P < 0.05) predictors. The variables presence of rodents, cats, wild animals and main activity showed statistical association (P < 0.05) with the seroprevalence of N. caninum. Due to the high prevalence of T. gondii and N. caninum found in this study, the absence of specific slaughterhouses for sheep and raw or undercooked sheep meat for human consumption we concluded that sheep can represent an important source of infection for humans.