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Anaplasmataceae bacteria are emerging infectious agents transmitted by ticks. The aim of this study was to identify the molecular diversity of this bacterial family in ticks and hosts, both domestic and wild, as well as blood meal sources of free-living ticks in northeastern Paraguay. The bacteria were identified using PCR-HRM, a method optimized for this purpose, while the identification of ticks and their blood meal was performed using conventional PCR. All amplified products were subsequently sequenced. The bacteria detected in the blood hosts included Ehrlichia canis, Anaplasma platys, and Anaplasma phagocytophilum, Candidatus Anaplasma boleense, and Wolbachia spp., which had not been previously reported in the country. Free-living and parasitic ticks on dogs (Canis lupus familiaris) and wild armadillos (Dasypus novemcinctus) were collected and identified as Rhipicephalus sanguineus and Amblyomma spp. The species E. canis, A. platys, A. phagocytophilum, and Ca. A. boleense were detected in domestic dog ticks, and E. canis and A. platys were found for the first time in armadillos and free-living ticks. Blood feeding sources detected in free-living ticks were rodents, humans, armadillos and dogs. Results show a high diversity of tick-borne pathogens circulating among domestic and wild animals in the northeastern region of Paraguay.

ABSTRACT: This study detected Anaplasma marginale in calvesusing blood smears and nested PCR (nPCR) and to compare the results with the clinical signs presented by calves on a dairy farm in the municipality of Castanhal, located northeast of the state Pará (1°07’19.1”S and 47°53’53.0”W), eastern Amazon. To this end, 192 blood samples were collected from 24 animals at 1-20, 21-41 and 42-60 days of age. Blood smears and nPCR with primers for the msp5 gene were performed. The prevalence of A. marginale was 61.5% (118/192) for the blood smear technique and nPCR (msp5). The manifestation of clinical signs of anaplasmosis also increased significantly over the course of the study (P < 0.0001), being lower in animals aged 1-20 days, but increasing among those aged 21-41 and 42-60 days. These signs were characterized by apathy, fever, weight loss, diarrhea, dehydration, and hypochromic mucous membranes. Regarding the evaluation of the diagnostic techniques, no significant difference was observed in the detection of A. marginale between the blood smear and nPCR (P = 0.995), but the agent’s rickets increased on Day 47 (P < 0.01) in both tests, thereby demonstrating a near-linear pattern of increase in rickets over the 60 days, with a consequent decrease in globular volume. This shows that of the 24 animals studied, 21 were infected at some point during the study period. Additionally, there was no significant difference between blood smears and nPCR, probably due to medium and high parasitemia, which were directly related to the clinical signs and decrease in globular volume.

Abstract The present study aimed for the molecular detection of Rickettsia spp. in ticks collected from military training areas in southeastern Brazil. Previously, a total of 9,374 free-living ticks in 66 military instruction areas of five Military Organizations (MOs) were collected. From these, a sample of 1,885 ticks was used for molecular analysis..DNA extraction was performed using the “HotSHOT” technique, and PCR was performed using the Rickettsia spp. gltA, 17kDa and ompA genes. It was found that 11 samples produced DNA sequences of sizes compatible with the Rickettsia spp. gltA and 17kDa gene and two of these, also for ompA, with a prevalence of 0.58% (11/1885). Analyses of amplified fragments of gltA identified the samples as Rickettsia bellii in seven nymphs of Amblyomma dubitatum and one nymph of Amblyomma sculptum, and identified samples as Rickettsia sp. in two nymphs of A. dubitatum and one of A. sculptum. This finding warns the possibility of the risk of exposure of military personnel to ticks infected with Rickettsia spp. during training.

Abstract 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.

The present study aimed to use polymerase chain reaction (PCR) to detect species of the order Piroplasmida, such as Anaplasma spp., Borrelia spp., and Ehrlichia spp., circulating in the blood of Didelphis aurita in a peridomiciliary environment. Blood samples collected from big-eared opossum (Didelphis aurita) were screened for hemoparasites using PCR. The extracted DNA was tested for tick-borne hemoparasites. We were unable to detect hemoparasites, such as Ehrlichia spp., Babesia spp., Anaplasma spp., and Borrelia spp. Theileria DNA was detected in only one sample screened using PCR for an approximately 650-base pair fragment of the 18S rRNA gene. Sequencing and BLAST analysis of a subset of the PCR amplicons revealed 97% (535/553 bp) identity with Theileria bicornis. The detection of Theileria sp. in D. aurita challenges us to pursue more in-depth studies of marsupial piroplasmosids and to evaluate the morphological aspects of the findings and their possible involvement in zoonoses.

Abstract Background Currently, various zoonotic diseases are classified as emerging or reemerging. Because equids have a direct relationship with various vectors, they are possibly more frequently exposed to zoonotic agents than are humans. The undeniable importance of diseases such as human granulocytic anaplasmosis, spotted fever, and leishmaniasis for both public and animal health, as well as the possibility of equids acting as sources, reservoirs, or even sentinels for these pathogens, justifies the detection of their frequency and factors associated with infection in equids from northeastern Brazil. Methods Blood samples were collected from 569 equids (528 horses, 33 donkeys, and 8 mules), 516 from a rural area and 53 from an urban area. Pathogen detection was carried out as follows: Borrelia spp. and Rickettsia spp., serological analysis; Leishmania spp., serological analysis and polymerase chain reaction (PCR); Anaplasma phagocytophilum, PCR. Determination of associated factors was carried out through generalized linear models. Results The frequencies of positivity for the pathogens observed in equids were as follows: Borrelia spp., 13.9% (79/569); Leishmania spp., 3.5% (20/569); Rickettsia spp. 33.4% (190/569). Regarding factors associated with infection, male sex was associated with protection against Borrelia spp.; donkeys and mules were associated with protection against Rickettsia spp., while a younger age was a risk factor. The infection of A. phagocytophilum was not detected in the sampled population. Co-infection was detected in 5.1% (29/569) of the animals. Conclusions Most of the studied pathogenic agents are present in the prospected area, indicating a possible risk for both human and animal health. This demonstrates that equids can be considered important sentinels in the assessment of pathogens with zoonotic potential in the region.

Abstract Tick-borne pathogens belong to one of the two main groups of occupational biohazards, and occupational exposure to such agents puts soldiers at risk of zoonotic infections, such as those caused by rickettsiae. There are few studies on acarological fauna and occupational risk in military areas in Brazil. Thus, the present study aimed to analyze the diversity of ticks present in the military training areas of municipalities in the Southeast Region of Brazil. The ticks were collected from the selected areas using the dragging and flagging techniques as well as by visual detection on the operators’ clothing, and environmental information was also recorded. A total of ten species were collected from the 66 surveyed areas, belonging to five genera and nine species: Amblyomma sculptum, Amblyomma dubitatum, Amblyomma brasiliense, Amblyomma longirostre, Amblyomma aureolatum, Dermacentor nitens, Rhipicephalus spp., Ixodes spp. and Haemaphysalis spp. The frequent presence of tick species in military training areas along with traces and sightings of wild animals, most commonly capybaras (Hydrochoerus hydrochaeris), in most of the studied areas, indicates high levels of exposure of the military to tick vectors of spotted fever group rickettsiae and the possible occurrence of infections among the troops.

Neste estudo avaliou-se a presença de espécies de carrapatos e a detecção de agentes patogênicos a eles associados. Os carrapatos de vida livre coletados em fragmentos florestais da área rural do Município de Divino, Minas Gerais, Brasil. Os carrapatos coletados foram divididos em dois grupos, aqueles que foram coletados na área da margem do fragmento (Borda) e os coletados no interior da floresta (Mata). Em todos os fragmentos, os carrapatos foram coletados de acordo com a técnica de arraste aéreo ou no chão e com o uso de perneiras e de flanela. Tanto, as larvas, quanto as ninfas e os adultos foram morfologicamente identificados usando chaves taxonômicas específicas. No caso das larvas, estas foram identificadas até o nível de gênero. Foi realizada extração de DNA dos carrapatos e o DNA extraído foi testado para a presença de Rickettsia spp., Borrelia spp., Ehrlichia spp., Anaplasma spp., Babesia spp., e Theileria spp. por meio de uma estratégia de reação em cadeia da polimerase convencional. No total, 1.122 carrapatos em fase de vida livre (750 larvas, 367 ninfas e 5 adultos) e 18 clusters de larvas foram usados no estudo. As principais espécies identificadas na população de carrapatos coletada foram: Amblyomma sculptum, Amblyomma auricularium, Amblyomma aureolatum e Amblyomma pseudoconcolor e larvas de Amblyomma spp. e Dermacentor spp. Como resultado da detecção de patógenos não foi possível achar DNA de nenhum dos agentes analisados, assim todas as amostras de DNA dos carrapatos testados foram negativas tanto para Rickettsia spp. quanto para Borrelia spp., Ehrlichia spp., Anaplasma spp., Babesia spp. e Theileria spp.

Avian borreliosis is a tick-borne acute septicemic disease that affects a variety of avian species and is caused by the bacterium Borrelia anserina. The present study aimed to establish the infection dynamics of B. anserina in experimentally infected Gallus gallus to determine its impact on the health and weight gain of the animals. Forty G. gallus were divided into four groups. Group 1 (G1) included 10 animals inoculated intramuscularly (IM) with 250?L of blood serum containing 3.7x106 spirochetes per milliliter. Group 2 (G2) included 10 animals inoculated IM with 250?L of saline 0.9%. Group 3 (G3) included 10 animals infested with four Argas miniatus nymphs (3rd instar) infected with B. anserina strain PL. Group 4 (G4) included 10 animals infested with four A. miniatus nymphs (3rd instar) free of infection by B. anserina. The number of spirochetes in the blood was directly proportional to the appearance of clinical signs and symptoms. This is the first study showing the experimental clinical evolution of the B. anserina PL strain in G. gallus. Additionally, the first assessments of spirochetaemia are presented, based on the direct count of bacteria in the serum by a Neubauer chamber, during the infection.

Abstract This study aimed to verify the presence of IgG antibodies against Borrelia burgdorferi sensu lato (s.l) in domestic dogs in western Cuba. Serum samples were analyzed by indirect enzyme-linked immunosorbent assay (ELISA), using crude antigens of a B. burgdorferi strain of North American origin. To verify the presence of Borrelia spp., deoxyribonucleic acid (DNA) extracted from individual blood samples was analyzed by nested-PCR, with markers targeted for amplification of portions of the flagellin B gene (flaB) present in Borrelia spirochetes. Ticks were also collected through inspection of the animals. Sera from 93 of 176 (52.84%) dogs were reactive to the indirect ELISA. Geographic prevalence varied from 54.35% (25/46) in Boyeros, 44.44% (20/45) in Cotorro, 66.67% (22/33) in Habana del Este, and 50% (26/52) in San José de las Lajas. There was no statistical difference between these tested variables. No blood samples analyzed were positive for the Borrelia flaB gene.

Abstract Spotted fever group rickettsioses are emerging diseases. In some of these diseases, domestic dogs act as sentinels. Canine serological studies have demonstrated that rickettsial dispersion is concentrated in rural areas, seroprevalence being higher where human rickettsioses are endemic. In Rio de Janeiro, the Atlantic forest vegetation has been devastated by urbanization. In this context, we aimed to detect Rickettsia spp. in urban areas of the West Zone of Rio de Janeiro. Sera from 130 dogs were tested by Indirect Immunofluorescence Assay, and ticks collected from these dogs were tested by polymerase chain reaction. We found the rate of serological reactions against R. rickettsii and R. parkeri in our study area to exceed those of rural and non-endemic areas, highlighting the importance of dogs as urban sentinels. The possibility of contact with opossums and capybaras increased the chances of exposure to Rickettsia spp., reinforcing the hypothetical link between the landscape and the rickettsial wild cycle. Rhipicephalus sanguineus sensu lato was the tick most frequently observed. PCR-positive samples showed similarity with R. rickettsii and R. felis, an emerging pathogen rarely reported from ticks. We observed that rickettsiae circulate in urban places and ticks from indoor environments, which may be involved in bacterial epidemiology.

Abstract The present study aimed to characterize the importance of the Anaplasma marginale, Babesia bovis and Babesia bigemina in the genesis of cattle tick fever (CTF) among dairy calves in the northwest of Minas Gerais, Brazil. Blood samples from 300 calves were collected, followed by DNA extraction and nested PCR using oligonucleotide primers to amplify fragments of the semi-nested for the msp5 gene (A. marginale), sbp-4 (B. bovis) and rap-1a (B. bigemina) Among the examined calves, the prevalence of A. marginale was 55.6% (n=167/300), B. bovis was 4.0% (n=12/300) and B. bigemina was 15.3% (n=46/300), by PCR techniques. Parasitic forms of A. marginale and B. bigemina were found in 36,3% and 2,6% of the blood smears while B. bovis was not detected. There was a statistical difference between the positivity of infected animals in the age groups 1 (10-70 days) and (>70-300 days) for A. marginale and B. bigemina. A total of 15 calves with the classic symptoms of disease were examined, and the samples obtained were confirmed as a simple infection by A. marginale through semi-nested PCR. These results confirm bovine anaplasmosis as the primary cause of CTF among the calves of dairy cattle within the studied area.

Abstract Rickettsia rickettsii is the causative agent of Brazilian spotted fever (BSF), for which humans and dogs are both susceptible. Dogs are sentinels in serological surveys, however, canine disease is rarely reported. Therefore, we aimed to evaluate natural infection by spotted fever group (SFG) Rickettsia spp. in dogs and ticks collected from domiciles close to forest fragments, featuring domestic–wildlife interface areas. Samples from 115 dogs and 135 ixodids were assessed by polymerase chain reactions (PCR) targeting the gltA gene for Rickettsia spp. and the ompA gene for the SFG rickettsial species. One dog (0.87%; 1/115) was positive for R. rickettsii. This dog presented nonspecific laboratory and clinical abnormalities (thrombocytopenia, hyperproteinemia, lymph node enlargement, emaciation, anorexia, and lethargy). Rickettsia parkeri was identified in 2.96% (4/135) of the ticks (Amblyomma sculptum, A. aureolatum, and Rhipicephalus sanguineus). This study confirmed the presence of SFG bacteria in non-endemic and preserved locations, where domestic and wild populations interact. We reinforce the fact that the dog is susceptible to natural R. rickettsii infection. Although this is a rare finding, preventive measures should be taken against BSF in the studied areas. Finally, R. parkeri infection is possibly being demonstrated in A. sculptum for the first time.

The objective of this study was to evaluate the biological parameters of Rhipicephalus microplus engorged females exposed to the arthropod growth regulator fluazuron. A commercial formulation based on fluazuron (Acatak®, Novartis) was administered topically to stabled cattle artificially infested with R. microplus larvae. The infestations occurred on four alternate days (days -21, -17, -13 and -6) taking as day 0 (zero) the day of treatment with a single dose of fluazuron for the treated group. Fifteen engorged females from each group were collected from the floor of the stalls at the end of the engorgement period (21 days) on pre-established days: before (day 0) and after treatment (days 4, 8 and 15), respectively. After cleaning and preparation of the engorged females in the laboratory, the following biological parameters were analyzed: weight of the engorged female, weight of the female after laying (spent female), laying period, weight of the posture, egg production index, reproductive efficiency index, hatching percentage, and nutritional index. The average weight of engorged females showed a significant reduction on all days after treatment in the exposed group. Aside from the weight after laying, all other biological parameters showed a significant reduction on the eighth post-treatment day due to exposure to fluazuron. Knowledge of the effects of an active principle on biological parameters in a population of ticks is essential for appropriate implementation of integrated management practices for parasite control.

The aim of this study was to determine the frequency of ticks positive for genus Rickettsia bacteria among ticks collected from domestic dogs in the Department of Piura, Peru, using polymerase chain reaction (PCR) analysis. Ticks were collected from dogs in urban areas of the metropolitan region of Piura, Peru. Only three species of ticks were identified; 977 Rhipicephalus sanguineus (180 nymphs, 417 females, and 380 males), Six Amblyomma triste females, and one Amblyomma tigrinum male. After classifying the specimens morphologically by stage, species, and sex, their total DNA was tested by PCR using primers that amplify fragments of the gltA, ompA, ompB, and htrA genes. The resulting positive sample was sequenced, compared to the GenBank database, and analyzed phylogenetically. The Rickettsia spp. infection rate in the tick pools was 0.2% (1/484); the positive specimen was an R. sanguineus tick. GenBank analysis of the positive sequence revealed 100% identify with Rickettsia felis; however, no products of the htrA, ompA and ompB genes were amplified from this sample. To the best of our knowledge, this is the first report of R. felis in R. sanguineus in Peru.

Abstract The study aimed to identify species of ticks present in the environment and among captive animals, in Mangaratiba, Rio de Janeiro, Brazil. Ticks were isolated from captive animals by manual examination and free-living ticks in the environment were captured using the flannel drag technique. A total of 91 ticks were obtained (51 adults, 25 nymphs and 15 larvae). The specimens were identified morphologically as Amblyomma sp., Amblyomma dubitatum, Amblyomma ovale and Amblyomma sculptum , and were distributed among five species of native mammals and an exotic bird. This study also reports the first case of infestation of the Australian emu (Dromaius novaehollandiae) by A. sculptum.

Abstract INTRODUCTION: Dogs play an epidemiological role in several vector-borne diseases that affect human and animal health worldwide. We aimed to identify rickettsial circulation among dogs with canine visceral leishmaniasis (CVL) from a region endemic for both diseases. METHODS: CVL-seropositive dogs were screened for spotted fever group rickettsiae using an indirect immunofluorescence assay. RESULTS: Among the CVL-positive dogs, anti-Rickettsia rickettsii antibodies were identified in one asymptomatic and one oligosymptomatic dog. CONCLUSIONS: This study shows low circulation of antibodies to R. rickettsii in CVL-seropositive dogs. It is recommended that surveillance studies in dogs should continue in order to monitor this scenario.

Os carrapatos (Acari: Ixodidae) são de importância médica e veterinária relevantes em todo o mundo por causa da variedade de agentes patogênicos que podem transmitir. No presente trabalho, foi realizada uma pesquisa para identificar Babesia spp. e Ehrlichia spp. em carrapatos coletados de cães de Cuba. Foram coletados 431 carrapatos de 378 cães, tendo sido identificados como pertencentes às espécies de Ripicephalus sanguineus sensu lato (s. 1). O DNA genômico foi extraído com protocolo usando fenol/clorofórmio. Os carrapatos foram organizados em “pools” e o DNA extraído foi testado pela reação em cadeia da polimerase (nPCR) para amplificar 398 pares de bases (pb) do DNA ribossômico 16S (rDNA) de Ehrlichia canis e PCR para amplificar aproximadamente 560 pb do DNA ribossômico 18S (rDNA). Dos 49 pools testados, 8,16% (n = 4/49) foram positivos para o E. canis por nPCR visando o gene do 16S rDNA e apenas um pool (n = 1/49; 2,04%) foi positivo para o gene 18S rDNA para Babesia canis. As quatro sequências obtidas para o fragmento de 16S rDNA foram idênticas entre si e resultaram em 100% de identidade com E. canis de diferentes países. A sequência obtida do gene do 18S rDNA para Babesia spp. apresentou semelhança de 100% com Babesia canis vogeli quando comparada às sequências depositadas no Genbank. Esta foi a primeira detecção molecular desses agentes no carrapato R. sanguineus s. l. em Cuba.

Toxoplasmose é um sério problema de saúde pública em todo o mundo, uma vez que pode causar morbimortalidade pré-natal e neonatal em seres humanos. Embora os cães não sejam hospedeiros definitivos de T. gondii, eles possuem um papel importante na disseminação mecânica dos oocistos. Este trabalho teve como objetivo realizar uma investigação soroepidemiológica de anticorpos anti-T. gondii em cães domésticos de sete municípios do estado do Rio de Janeiro, Brasil. A partir de banco de soros caninos procedentes de diferentes municípios do estado do Rio de Janeiro, realizou-se um estudo epidemiológico analítico transversal para avaliação do perfil de anticorpos da classe IgG antiT. gondii em cães. Os municípios estudados foram Cachoeiras de Macacu, Guapimirim, Itaboraí, Magé, Resende, Seropédica e Silva Jardim. A detecção de anticorpos da classe IgG anti-T. gondii, foi realizada utilizando-se do ensaio de imunoadsorção enzimático (ELISA) indireto e as análises estatísticas usadas foram os testes de Qui-quadrado e a razão de prevalência. Das 651 amostras testadas, 300 foram reativas para T. gondii, representando uma frequência relativa de 46,08% de cães sororreativos. Concluiu-se que cães são bons sentinelas para avaliações de risco para ocorrência de T. gondii, enfatizando-se aqueles procedentes de áreas rurais e que não houve diferença na ocorrência de cães sororreativos frente a diferentes municípios do estado do Rio de Janeiro.

Os cães domésticos podem ser infectados por diferentes agentes zoonóticos, assumindo uma importância epidemiológica na distribuição espacial destes agentes. O objetivo do presente trabalho foi detectar a frequência de anticorpos contra Toxoplasma gondii e B. burgdorferi lato sensu em cães domiciliados no município de Castanhal, estado do Pará, Brasil. Foram estudados 186 cães (machos= 88, fêmeas= 98) de diferentes faixas etárias (0 a 6 meses, >6 meses a 2 anos, > 2 anos). As coletas das amostras foram realizadas por conveniência em 148 animais domiciliados em bairros localizados na zona urbana e 38 cães residentes na zona rural. Anticorpos contra T. gondii e B. burgdorferi lato sensu foram detectados em 59,7% e 80,1% dos animais examinados, respectivamente. Anticorpos contra os dois agentes foram detectados em 48,4% (90/186) dos cães. Conclui-se que os cães domésticos domiciliados em áreas urbana e rural do município de Castanhal, estado do Pará, são expostos à infecção por T. gondii e B. burgodoferi lato sensu, sendo os animais com faixa etária superior a dois anos os mais frequentemente infectados.

O objetivo do presente estudo foi determinar a frequência de carrapatos coletados de caninos domésticos positivos para bactérias do gênero Rickettsia por meio da Reação em cadeia da polimerase (PCR) no Departamento de Piura, Peru. Desta forma, carrapatos foram coletados de caninos de zonas urbanas da região Metropolitana de Piura, Peru. Apenas três espécies de carrapatos foram identificadas, sendo 977 R. sanguineus (180 ninfas, 417 fêmeas e 380 machos), 6 fêmeas da espécie Amblyomma triste e um macho Amblyomma tigrinum. Após classificados morfologicamente por estádio, espécie e sexo, o DNA total dos espécimes foi testado pela PCR utilizando iniciadores que amplificam fragmentos dos genes gltA, ompA, ompB e htrA. A amostra positiva foi sequenciada, comparada com o banco de dados depositados no GenBank e analisada filogeneticamente. Verificou-se, mediante PCR, uma taxa de infecção de 0,2% (1/484) “pools” de carrapatos positivos para Rickettsia spp. O espécime positivo foi um carrapato Rhipicephalus sanguineus. A análise no GenBank da sequência positiva apresentou uma similaridade de 100% com a espécie R. felis. Essa amostra não amplificou produtos para os genes htrA, ompA e ompB. Este é o primeiro relato de R. felis em R. sanguineus no Peru.

The aim of this study was to investigate the presence of anti-Rickettsia spp. antibodies, the tick fauna, and the ticks that are carriers of rickettsiae of the spotted fever group (SFG). About 68 (24%) of the 283 serum samples tested by indirect immunofluorescence (IFA) reacted against the R. rickettsii crude antigen. The titers varied between 1:64 and 1:512. At the time of collection, 189 (64.5%) of the 293 dogs included in this study, were infested with ticks. Ticks classified as Rhipicephalus sanguineus and Amblyomma sculptum were identified. None of the ticks examined for SFG rickettsiae using polymerase chain reaction (PCR) were positive. The presence of the anti-R. rickettsii antibodies detected by IFA, albeit at low titers, suggests the circulation of SFG rickettsiae, which requires permanent surveillance because there are records on human fatalities related to spotted fever and to avoid any future threats to the students moving extensively in the areas near of the Rural Federal University of Rio de Janeiro.

The objective of this study was to assess the occurrence of antibodies against Anaplasma marginale, Babesia bovis and Babesia bigemina in beef cattle of the northern and central-western regions of Brazil. A total of 1703 blood samples were collected from cattle from 100 farms distributed among 37 municipalities in the states of Mato Grosso, Pará and Tocantins. The search for antibodies was conducted using an indirect enzyme-linked immunosorbent assay (ELISA), and antibodies were observed for B. bovis, B. bigemina and A. marginale in cattle from Mato Grosso, Tocantins and Pará at rates of 99%, 90% and 41%; 99%, 70% and 52%; and 97%, 97% and 75%, respectively. The results show that the analyzed regions exhibit enzootic stability for infection with B. bovis and B. bigemina, whereas the same result was not observed with A. marginale.

ABSTRACT. Cordeiro M.D., Raia V.A., Valim J.R.A., Castro G.N.S., Souza C.E. & Fonseca A.H. [Frequency of antibodies class IgG anti-Rickettsia rickettsii in horses of Universidade Federal Rural do Rio de Janeiro, Seropédica campus.] Frequência de anticorpos da classe IgG anti-Rickettsia rickettsii em equinos na Universidade Federal Rural do Rio de Janeiro, Campus Seropédica. Revista Brasileira de Medicina Veterinária, 37(1):78-82, 2015. Departamento de Epidemiologia e Saúde Pública, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Campus Seropédica, BR 465, Km7, Seropédica, RJ 23890-000, Brasil. E-mail: adivaldo@ufrrj.br The aim of this study was to verify, through the indirect immunofluorescence assay (IFA), the frequency of anti-Rickettsia rickettsii antibodies in horses at Universidade Federal Rural do Rio de Janeiro (UFRRJ) Seropédica campus, state of Rio de Janeiro. We analyzed serum samples from 42 horses from Department of Breeding Equine of UFRRJ. All samples were tested using fixed slides with antigens for R. rickettsii, Rickettsia rhipicephali and Rickettsia parkeri. We observed an overall prevalence of Rickettsia spp. 83.33% (35/42). For the agent R. rickettsii revealed a prevalence of 66.67% (28/42), still being categorized in titers of 1:64 (19/28) and 1:128 (9/28). Nine of the 28 positives horses for R. rickettsii (21.43%) were no reactive to other agents, with titers 1:64 (8/9) and 1:128 (1/9). The only tick species found parasitizing horses on the campus of UFRRJ during the collection period were Amblyomma cajennense and Dermacentor nitens. The UFRRJ presents an environment that provides a ideal epidemiological niche for the permanence of Rickettsia bacteria. The high prevalence found in this study indicates that attention to epidemiological agent of Brazilian Spotted Fever in the study area is of utmost importance. The aim of this study was to verify, through the indirect immunofluorescence assay (IFA), the frequency of anti-R. rickettsii antibodies in horses at Universidade Federal Rural do Rio de Janeiro (UFRRJ) Seropédica campus, state of Rio de Janeiro. We analyzed serum samples from 42 horses Department Breeding Equine of UFRRJ. All samples were tested using fixed slides with antigens for R. rickettsii, Rickettsia rhipicephali and Rickettsia parkeri. We observed an overall prevalence of Rickettsia spp. 83.33% (35/42). For the agent R. rickettsii revealed a prevalence of 66.67% (28/42), still being categorized in titers of 1:64 (19/28) and 1:128 (9/28). Nine of the 28 positives horses for R. rickettsii (21.43%) were no reactive to other agents, with titers 1:64 (8/9) and 1:128 (1/9). The only tick species found parasitizing horses on the campus of UFRRJ during the collection period were Amblyomma cajennense and Dermacentor nitens. The UFRRJ presents an environment that provides an ideal epidemiological niche for the circulation of rickettsia bacteria. The high prevalence found in this study indicates a probable circulation of Rickettsia spp., having thus risk for human infection in the study area

Among the major diseases that affect cattle and water buffaloes, the tick-borne diseases are detaches. Bovine babesiosis caused by Babesia bigemina and Babesia bovis, and anaplasmosis, caused by Anaplasma marginale rickettsia, are of great economic importance to cattle diseases. The aim of this study was to compare the serologic occurrence for the agents of tick fever in cattle and water buffaloes in the middle region southeast of the state of Pará, northern Brazil. Blood samples were collected from 679 beef cattle (Nelore) and 430 water buffaloes (Mediterranean and Murrah) in eight cities of middle region southeast of Pará, Brazil. The research of antibodies IgG against A. marginale, B. bigemina and B. bovis was performed through of the indirect enzyme-linked immunosorbent assay (iELISA). Cattle compared to buffaloes showed higher occurrence of antibodies against B. bovis (97,34% and 33.95%), B. bigemina (97,34% and 27.21%) and A. marginale (74,52% and 47.90%), respectively. The probability of cattle are serologically positive to A. marginale, B. bovis and B. bigemina was 1,5 (74,52/47,90%), 3,58 (97,34/27,21%) and 2,87 (97,34/33,95%) times higher than that buffaloes, respectively. These results suggest that buffaloes may be more resistant to vectors being subjected to a lower rate of infection than cattle.

ABSTRACT. Cunha N.C., Lemos E.R.S., Rozental T., Teixeira R.C., Cordeiro M.D., Lisbôa R.S., Favacho A.R., Barreira J.D., Rezende J. & Fonseca A.H. Rickettsiae of the Spotted Fever group in dogs, horses and ticks: an epidemiological study in an endemic region of the State of Rio de Janeiro, Brazil. [Rickettsias do grupo da febre maculosa em cães, equinos e carrapatos: um estudo epidemiológico em região endêmica do estado do Rio de Janeiro, Brasil.] Revista Brasileira de Medicina Veterinária, 36(3):294-300, 2014. Departamento de Epidemiologia e Saúde Pública, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, BR 465, Km 7, Seropédica, RJ 23890-000, Brasil. E-mail: adivaldo@ufrrj.br Spotted fever is a disease of which Rickettsia rickettsii is the most pathogenic agent. Its transmission is by tick bites and the infected ticks can act as vectors, reservoirs or amplifiers. The purpose of this paper is to assess the potential of dogs and horses as sentinels for brazilian spotted fever (BSF) emergence and become acquainted with the tick species in a municipal region of Resende, Rio de Janeiro State, Brazil, where five BSF cases in man were registered. Dog and horse blood samples were collected from rural and periurban properties to assess IgG anti-Rickettsia rickettsii, using the indirect immunofluorescence assay (IFA). First, an analysis was conducted to detect association between IFA results and answers obtained from a questionnaire. Afterwards, a multivariate investigation was undertaken that presented significant statistical differences. Ticks were collected directly from dogs and horses for taxonomic identification. Out of the 107 canine serum samples, 30 (28.0%) were reactive, with titers varying from 1:64 to 1:4096, and 77 (72.0%) were not reactive. Of 96 animals in the serum analysis of horses, 9 (9.4%) were reactive, all with titers of 1:64, and 87 (90.6%) were non-reactive. The tick species collected from dogs were Rhipicephalus sanguineus, Amblyomma sculptum, Amblyomma aureolatum, Amblyomma ovale, Rhipicephalus microplus and nymphs of Amblyomma sp., R. sanguineus and R. microplus. Adult ticks gathered from horses were A. cajennense, R. microplus and Dermacentor nitens, in addition to nymphs of Amblyomma sp., R. microplus and D. nitens. The results suggest that: (i) the habit of dogs entering forests and living in rural environments positively influenced the presence of anti-rickettsiae of the spotted fever group serum antibodies, (ii) horses were not good sentinels for this study area and (iii) R. sanguineus as well as A. cajennense ticks were the most prevalent ixodidae fauna of the region.

O protozoário, Theileria equi é um dos principais agentes transmitidos por carrapatos aos equídeos, causando sérios entraves à equideocultura no Brasil. Sua epidemiologia no país ainda apresenta lacunas. Assim, este estudo objetivou realizar o diagnóstico sorológico e avaliar os fatores de risco em equinos de uso militar situados no município de Resende, Rio de Janeiro. Amostras de 174 equinos foram testadas através do ensaio de adsorção imunoenzimática indireta (iELISA) utilizando antígeno parcialmente purificado de T. equi. A variável dependente (sororeatividade) foi testada, através de análise bivariada, quanto à associação às variáveis independentes (gênero, idade, definição racial, grupo de manejo, tempo de criação na Academia Militar das Agulhas Negras (AMAN), sistema de criação, origem do equino, presença e grau de infestação por carrapatos). As variáveis com associação na análise bivariada (p≤0,25) foram incluídas no modelo de regressão logística. Verificou-se que a soroprevalência para T. equi foi de 74,14%. A análise multivariada demonstrou que o tempo de criação na AMAN superior à 15 anos está associado à soropositividade para T. equi (OR: 5,70; IC: 1,23 - 22,1). Pode-se inferir que a área é endêmica, com alta prevalência de portadores assintomáticos, e em estabilidade enzoótica. Isto evoca cuidados e medidas preventivas na introdução de equinos no rebanho.

Abstract This study aimed to perform a morphological, molecular and phylogenetic characterization of Borrelia theileri obtained from infected Rhipicephalus microplus in Brazil. Fifty engorged R. microplus females from cattle in the municipality of Seropédica, Rio de Janeiro, were analyzed for spirochetes by hemolymph smear. Macerated eggs and positive ticks, as well as blood from the bovine infested by these ticks, were analyzed the glpQ, flaB and hpt genes by PCR. The PCR products were purified and sequenced for analysis and construction of a phylogenetic tree. Only 2% (1/50) of the ticks generated a positive result by both smear and PCR. The spiral forms (n = 50) had (media ± SD) a mean length of 19.17 ± 4.12 µm, diameter of 0.2935 ± 0.0469 and number of turns 8.44 ± 2.59. Sequence alignments of the three evaluated genes exhibited 98% similarity to B. theileri isolates, occurring in a clade highly related to B. theileri strain KAT. Egg maceration samples were positive for the three evaluated genes, whereas bovine blood was negative by PCR. This is the most detailed characterization of B. theileri in the Americas to-date, presenting morphological, molecular and phylogenetic data, including the transovarial transmission of the spirochete in the host tick.

Abstract This study evaluated the influence of the initial weight, feeding period and temperature on weight gain and biological parameters of the non-parasitic phase of partially engorged Rhipicephalus sanguineus females that were artificially fed using plastic tips as feeding devices. The device did not alter the oviposition of the females or any other parameters evaluated. Furthermore, it was observed that the temperature of the feeding the group did not affect the weight gain and biology of ticks. This device has great potential for the development of studies on bioagent transmission because it provides higher intake of blood by ixodid ticks.

Abstract The aim of this study is to detect the presence of tick-borne agents of genera Rickettsia, Borrelia, Babesia, Ehrlichia and Anaplasma in ticks collected from native wild birds in the state of Rio de Janeiro. Birds were captured and observed carefully to find the ectoparasites. DNA detection of hemoparasites was performed by means of the polymerase chain reaction (PCR). The sequences obtained were analyzed and their homologies were compared to the available isolates in the GenBank platform database. A total of 33 birds were captured from 20 different species, of which 14 were parasitized by Amblyomma longirostre (n = 22). There was absence of DNA from agents of the genera Babesia, Anaplasma and Ehrlichia in the evaluated samples. The phylogenetic analysis indicated that one sample had 100% identity with Rickettsia bellii (KJ534309), the other two samples showed 100% identity with Rickettsia sp. Aranha strain and strain AL (EU274654 and AY360216). The positive sample for R. bellii was also demonstrated to be positive for Borrelia sp., which presented a similarity of 91% with Borrelia turcica (KF422815). This is the first description of Borrelia sp. in ticks of the genus Amblyomma in South America.