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1.
Parasitol Res ; 122(10): 2367-2377, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37587388

RESUMO

Human contact with wild animals in synanthropic habits is often mediated by arthropod vectors such as ticks. This is an important method of spreading infectious agents that pose a risk to human health. Thus, this study aimed to molecularly detect Ehrlichia spp., Anaplasma spp., Borrelia spp., and protozoa of the order Piroplasmida in ticks collected from coatis of Iguaçu National Park (PNI), Paraná, Brazil. This study involved 553 ticks DNA, including Amblyomma spp. larvae, Haemaphysalis juxtakochi nymphs, Amblyomma brasiliense, Amblyomma coelebs, and adults of Amblyomma ovale. The DNA extracted from each sample was subjected to polymerase chain reaction (PCR) targeting the genes 23S rRNA for the Anaplasmataceae family, 16S rRNA for Anaplasma spp., dsb for Ehrlichia spp., flaB, 16S rRNA, hpt, and glpQ for Borrelia spp., and 18S rRNA for Piroplasmid protozoans. DNA from Anaplasma sp. was detected in ticks of the species A. coelebs (4/553); Borrelia sp. DNA was detected in A. coelebs (3/553), A. ovale (1/553), and Amblyomma larvae (1/553); and Theileria sp. was detected in A. coelebs (2/553). All tested samples were negative for Ehrlichia spp. Our study constitutes the newest report in South America of these microorganisms, which remain poorly studied.


Assuntos
Borrelia , Procyonidae , Carrapatos , Adulto , Animais , Humanos , RNA Ribossômico 16S/genética , Brasil , Parques Recreativos , Ecossistema , Florestas , Amblyomma , Anaplasma/genética , Borrelia/genética , Ehrlichia/genética , Larva
2.
Trop Anim Health Prod ; 55(3): 214, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37209270

RESUMO

The present study aimed to describe the occurrence of Borrelia spp. in cattle in the states of Minas Gerais and Pará in southeastern and northern Brazil, respectively. Bovine whole blood samples were examined by blood smear and polymerase chain reaction (PCR) to detect the flagellin B (flaB) gene of Borrelia spp. Frequencies of positive animals for Borrelia spp. were 1.52% (2/132) in the municipality of Unaí, Minas Gerais, and 14.2% (2/7) in the municipality of Marabá, Pará. Subsequent genetic sequencing confirmed that the detected spirochetes close to the species B. theileri. In both locations, the animals positive for B. theileri were also highly infested by Rhipicephalus microplus ticks. Despite the low frequency of Borrelia spp., the occurrence of this spirochete indicates that further studies are needed to determine the consequences in cattle herds.


Assuntos
Borrelia , Rhipicephalus , Bovinos , Animais , Brasil/epidemiologia , Borrelia/genética , Reação em Cadeia da Polimerase/veterinária
3.
Ticks Tick Borne Dis ; 13(6): 102037, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36270115

RESUMO

This study evaluates the presence of bacterial and protozoan agents in ticks and fleas found on wild animals in the state of Rio de Janeiro, Brazil. These ectoparasites were collected on mammal species Hydrochoerus hydrochaeris, Tapirus terrestris, Dicotyles tajacu, Didelphis aurita, Cuniculus paca, Cerdocyon thous, and Coendou prehensilis, and on the terrestrial bird Dromaius novaehollandiae. Ticks and fleas were identified morphologically using specific taxonomic keys. A total of 396 ticks and 54 fleas were tested via polymerase chain reaction (PCR) for the presence of Rickettsia spp., Borrelia spp., microorganisms of the order Piroplasmida and Anaplasmataceae family. This total is distributed among nine tick species of the genus Amblyomma and one flea species. Rickettsia bellii was detected in Amblyomma dubitatum and Amblyomma pacae; Rickettsia sp. strain AL was found in Amblyomma longirostre; Rickettsia parkeri strain Atlantic rainforest was found in Amblyomma ovale; and "Candidatus Rickettsia senegalensis" and Rickettsia felis were detected in Ctenocephalides felis felis. Wolbachia sp. was detected in C. f. felis, and Borrelia sp. was detected in Amblyomma calcaratum (here named Borrelia sp. strain Acalc110). All tested samples were negative for Ehrlichia spp. and microorganisms of the Piroplasmida order. This study detected a new bacterial strain, Borrelia sp. strain Acalc 110 (which is genetically close to B. miyamotoi and B. venezuelensis) and the Rickettsia sp. strain 19P, which is 100% similar to "Ca. R. senegalensis", a bacterium recently discovered and now being reported for the first time in Brazil.

4.
Parasit Vectors ; 15(1): 295, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999566

RESUMO

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.


Assuntos
Doenças do Cão , Ehrlichiose , Animais , Cuba , Doenças do Cão/microbiologia , Cães , Ehrlichia , Ehrlichia canis/genética , Ehrlichiose/microbiologia , Ehrlichiose/veterinária , Genótipo , Filogenia
5.
Vet Parasitol Reg Stud Reports ; 30: 100706, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35431064

RESUMO

Dogs are important in the epidemiology of tick-borne diseases, playing a significant role mainly in endemic areas of rickettsiosis and borreliosis, and serving as sentinels in epidemiological surveys. We analyzed the distribution of Rickettsia and Borrelia spp. in dogs and their ticks in the municipalities of Guaxupé, Minas Gerais, and Tapiratiba, São Paulo, Brazil, two areas non-endemic for Baggio-Yoshinari Syndrome (BYS) and rickettsiosis. Serum from 242 dogs of different ages (>12 months) and breeds were tested by the Indirect Immunofluorescence Assay (IFA) using specific antigens for Rickettsia rickettsii, Rickettsia parkeri, Rickettsia amblyommatis, Rickettsia rhipicephali, and Rickettsia bellii, and by an indirect Enzyme Linked Immunosorbent Assay (ELISA) for the detection of homologous IgG antibodies against Borrelia burgdorferi American strain G39/40. Ticks were collected from the animals and subjected to PCR and nested PCR for detection of Rickettsia spp. (synthase citrate gene) and Borrelia spp. (flagellin gene). Serological data showed that 7.85% (19/242) of the analyzed dogs were seropositive for at least one of the five Rickettsia antigens tested; one (0.41%) was considered seropositive for R. parkeri (1:64) and one (0.41%) for R. rickettsii (1:256). Nine (3.72%) were considered seropositive for R. bellii and one (0.41%) for R. amblyommatis; a seroprevalence of 13.64% (33/242) for IgG class immunoreactive antibodies against B. burgdorferi was observed. A total of 148 ticks were collected from the dogs; among these 3.40% were identified as larvae of the genus Rhipicephalus and 0.70% of the genus Amblyomma; 89.8% were identified as Rhipicephalus sanguineus, 4.70% Amblyomma sculptum and 1.40% Amblyomma ovale; all negative for PCR of Rickettsia spp. and nested PCR for Borrelia spp.. The serological findings of this study suggest the circulation of Rickettsiae associated with the spotted fever group and vector ticks, just like Borrelia spp. in a non-endemic Brazilian area, drawing attention to the possibility of a zoonotic cycle in the region.


Assuntos
Borrelia , Doenças do Cão , Rhipicephalus sanguineus , Infecções por Rickettsia , Rickettsia , Amblyomma , Animais , Brasil/epidemiologia , Doenças do Cão/microbiologia , Cães , Imunoglobulina G , Rickettsia/genética , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/microbiologia , Infecções por Rickettsia/veterinária , Estudos Soroepidemiológicos
6.
Parasit Vectors ; 14(1): 275, 2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34022939

RESUMO

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.


Assuntos
Equidae/parasitologia , Leishmaniose/veterinária , Doença de Lyme/veterinária , Infecções por Rickettsia/veterinária , Zoonoses/epidemiologia , Zoonoses/parasitologia , Anaplasma/isolamento & purificação , Anaplasma/patogenicidade , Anaplasmose/epidemiologia , Animais , Borrelia/isolamento & purificação , Borrelia/patogenicidade , Brasil/epidemiologia , Feminino , Leishmania/isolamento & purificação , Leishmania/patogenicidade , Leishmaniose/epidemiologia , Doença de Lyme/epidemiologia , Masculino , Rickettsia/isolamento & purificação , Rickettsia/patogenicidade , Infecções por Rickettsia/epidemiologia
7.
Vet Parasitol Reg Stud Reports ; 16: 100268, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31027602

RESUMO

This study aims to evaluate the infection's clinical parameters and genetic diversity of msp1α of the AmRio1 strain in acute and chronic infections in cattle and ticks. A calf experimentally infected with the A. marginale AmRio1 strain was monitored during acute infection, and the presence of the msp1α gene was verified in the semi-nested polymerase chain reaction (PCR) during the acute and persistent phases of infection. From day seven after inoculation of the pathogen, the calf showed an increase in body temperature, decrease in hematocrit and increase in the percentage of cells infected by the agent, as well as clinical signs. Blood samples from the experimentally infected calf were positive during the acute infection and the persistent PCR infection for the msp1α gene. During the acute phase, infestation with Rhipicephalus microplus was performed. To evaluate the chronic phase, a blood sample was collected at 90 days post-infection. There was no variation of the MSP1a protein in this study. The AmRio1 strain was pathogenic as it caused severe changes in the clinical parameters of the monitored cattle. The positivity of this strain in organs and saliva of the analyzed ticks indicates a probable biological transmission.


Assuntos
Anaplasma marginale/genética , Anaplasmose/microbiologia , Vetores Aracnídeos/microbiologia , Proteínas da Membrana Bacteriana Externa/genética , Doenças dos Bovinos/microbiologia , Rhipicephalus/microbiologia , Sequência de Aminoácidos , Anaplasma marginale/classificação , Anaplasmose/transmissão , Animais , Proteínas da Membrana Bacteriana Externa/química , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/transmissão , Reação em Cadeia da Polimerase , Saliva/microbiologia
8.
Parasitol Res ; 117(10): 3109-3118, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30033488

RESUMO

Equine piroplasmosis is a disease of Equidae, including horses, donkeys, mules, and zebras, caused by either Theileria equi or Babesia caballi. This disease represents a serious problem for the horse industry and its control is critical for the international trade of horses. The objective of the present study was to detect B. caballi and T. equi infections in horses reared in western Cuba. Blood samples from 100 horses were tested for the presence of piroplasms by using Giemsa-stained blood smears and nested PCR (nPCR) assays targeting merozoite antigen genes of B. caballi (bc48) and T. equi (ema-1). All animals were inspected for the detection of tick infestation and tick specimens were collected for species identification. Erythrocyte inclusions were observed in 13 (13%) of the analyzed samples. nPCR analysis showed that 25 (25%) samples were positive for B. caballi, 73 (73%) for T. equi, and 20 (20%) showed dual infections. Only one tick species was found infesting horses, Dermacentor nitens. In addition, three nearly full-length sequences of T. equi 18S rRNA gene were obtained and subjected to phylogenetic analyses. This study reports a high prevalence of T. equi and B. caballi single and coinfections in horses in western Cuba. Molecular analysis of the 18S rRNA gene of T. equi suggested that different genotypes of this hemoparasite circulate in Cuba. To the best of our knowledge, this is the first report describing the molecular detection of B. caballi and T. equi in horses in Cuba.


Assuntos
Babesia/genética , Babesiose/epidemiologia , Doenças dos Cavalos/parasitologia , Cavalos/parasitologia , Theileria/genética , Theileriose/epidemiologia , Infestações por Carrapato/veterinária , Animais , Babesia/isolamento & purificação , Bovinos , Coinfecção , Cuba/epidemiologia , Equidae/parasitologia , Feminino , Masculino , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Theileria/isolamento & purificação , Carrapatos/parasitologia
9.
Trop Anim Health Prod ; 50(4): 831-836, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29388162

RESUMO

Borrelia burgdorferi sensu stricto is the main etiological agent of Lyme disease (LD) in the USA. In Brazil, it is believed that a similar spirochete is the causal agent of the Baggio-Yoshinari syndrome (BYS), a zoonosis also transmitted by ticks, whose clinical manifestations are similar to those of LD. Despite the epidemiological importance, there are no studies reporting the presence and the prevalence of B. burgdorferi among horses in Mato Grosso State. The aim of this study was to detect and measure the frequency of IgG antibodies anti-B. burgdorferi American strain G39/40 in horses in the municipality of Sinop, MT-Brazil, using the indirect enzyme-linked immunosorbent assay (ELISA) for serological diagnosis. Blood samples from 367 horses were collected in 81 farms. An epidemiological questionnaire was applied during the visits to obtain information related to the animals and the farms. From the 367 horses, 214 were positive for B. burgdorferi sensu stricto according to the results of the ELISA test, representing an apparent prevalence of 54.04% [CI = 0.4548051-0.6237234]. Concomitantly, 89 blood samples were taken for molecular analysis by nested polymerase chain reaction (PCR). According to the PCR test results, none of the samples were reactive, although 53 of these samples were reactive according to ELISA. Seventy five farms (92.59%) had at least one reactive horse for B. burgdorferi. Our results support the hypothesis of the presence of anti-Borrelia spp. antibodies in horses in Mato Grosso, reaching a high animal prevalence. Besides that, leisure/sport purposes proved to be a risk factor, with an odds ratio of 3.16. These findings clearly indicate the need of borreliosis control in Sinop and make a significant contribution to the knowledge of the disease in Mato Grosso.


Assuntos
Infecções por Borrelia/veterinária , Borrelia burgdorferi/isolamento & purificação , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/microbiologia , Animais , Infecções por Borrelia/epidemiologia , Brasil/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Cavalos , Humanos , Doença de Lyme , Reação em Cadeia da Polimerase , Prevalência , Zoonoses
10.
Ticks Tick Borne Dis ; 9(1): 93-96, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29102467

RESUMO

This study aimed to evaluate, by means of artificial feeding, the interaction between a pathogenic rickettsia and the hard tick R. microplus. We used partially engorged females fed on calves free of Rickettsia spp. Group 1 (G1), containing 20 ticks, was fed bovine blood only. Group 2 (G2), containing 20 ticks, was fed blood containing uninfected VERO cells, and group 3 (G3), containing 40 ticks, was fed blood containing VERO cells infected with Rickettsia parkeri. Biological parameters of the non-parasitic phase and a possible bacterial transmission to the tick eggs and to guinea pigs were evaluated. At the end of oviposition, all G3 females were PCR-positive for genes specific for the genus Rickettsia. Although no guinea pigs were infected, the experimental infection of R. microplus by R. parkeri caused a deleterious effect on the oviposition and provided the first report of transovarian transmission of rickettsia in this tick.


Assuntos
Oviposição , Rhipicephalus/microbiologia , Rhipicephalus/fisiologia , Rickettsia/fisiologia , Animais , Chlorocebus aethiops , Feminino , Cobaias , Reação em Cadeia da Polimerase , Rickettsia/genética , Infecções por Rickettsia/transmissão , Células Vero/microbiologia
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