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1.
Exp Appl Acarol ; 92(3): 463-477, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38361037

RESUMO

Ticks are hematophagous arthropods and, during feeding, may transmit pathogens to vertebrate hosts, including humans. This study aimed to investigate the presence of Rickettsia spp. in ticks collected between 2010 and 2013 from free-ranging capybaras (Hydrochoerus hydrochaeris) and opossums (Didelphis albiventris) that inhabit Sabiá Park in Uberlândia, Brazil. Overall, 1,860 ticks were collected: 1,272 (68.4%) from capybaras (487 of the species Amblyomma sculptum, 475 adults and 12 nymphs; 778 Amblyomma dubitatum, 727 adults and 51 nymphs; and seven larva clusters of the genus Amblyomma); and 588 (31.6%) from opossums (21 A. sculptum, one adult and 20 nymphs; 79 A. dubitatum, all nymphs; 15 Ixodes loricatus, 12 adults and three nymphs; 457 Amblyomma sp. larva clusters; 15 Ixodes sp. larva clusters; and one Argasidae larva cluster). Out of 201 DNA samples tested for the presence of Rickettsia spp. DNA using polymerase chain reaction (PCR) 12 showed amplification of a gtlA gene segment that was specific to Rickettsia bellii, a bacterium non-pathogenic to humans. As there has been a report showing serological evidence of infections caused by Rickettsia species of the spotted fever group (SFG) in capybaras and opossums in the park, including Rickettsia rickettsii, the etiological agent of Brazilian spotted fever, and considering the presence of A. sculptum ticks, which are aggressive to humans, as well as these vertebrate hosts, which are amplifiers of R. rickettsii, it is important to monitor the presence of SFG rickettsiae in the Sabiá Park, which is visited daily by thousands of people.


Assuntos
Didelphis , Ixodidae , Larva , Ninfa , Rickettsia , Animais , Brasil , Rickettsia/isolamento & purificação , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Ninfa/fisiologia , Larva/microbiologia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Ixodidae/microbiologia , Ixodidae/crescimento & desenvolvimento , Ixodidae/fisiologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Infestações por Carrapato/epidemiologia , Feminino , Parques Recreativos , Amblyomma/microbiologia , Amblyomma/crescimento & desenvolvimento , Masculino , Roedores/parasitologia , Gambás/parasitologia
2.
Am J Trop Med Hyg ; 110(1): 36-39, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37956445

RESUMO

Chagas disease (CD) is a parasitic infection caused by the parasite Trypanosoma cruzi. Reports of CD cases associated with oral transmission have increased, particularly in Colombia, Brazil, and Venezuela. In this investigation, parasitological, serological, and molecular tests were conducted on samples obtained from humans, mammal reservoirs, and hosts involved in the assessment of a suspected oral transmission outbreak in Cubara, Boyaca, Colombia. Seropositivity was observed in 60% (3 of 5) of index patients and 6.4% (5 of 78) of close contacts. Trypanosoma cruzi DNA was detected by quantitative polymerase chain reaction in 100% of index cases, 6.4% (5 of 78) of close contacts, 60% (6 of 10) of canines, and 100% (5 of 5) of opossums. In all index cases, the TcI lineage was identified, along with two cases of mixed infection (TcI/TcII-TcVI). Hemoculture revealed a flagellate presence in 80% of opossums, whereas all triatomine bugs tested negative. Our findings suggest a potential oral transmission route through contamination with opossum secretions.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Animais , Cães , Colômbia/epidemiologia , Trypanosoma cruzi/genética , Surtos de Doenças , Gambás/parasitologia , Mamíferos , Genótipo , Reservatórios de Doenças/parasitologia
3.
J Wildl Dis ; 59(4): 673-683, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37846907

RESUMO

Chagas disease, a significant public health concern in the Americas, is caused by a protozoan parasite, Trypanosoma cruzi. The life cycle of T. cruzi involves kissing bugs (Triatoma spp.) functioning as vectors and mammalian species serving as hosts. Raccoons (Procyon lotor) and opossums (Didelphis virginiana) have been identified as important reservoir species in the life cycle of T. cruzi, but prevalence in both species in the southeastern US is currently understudied. We quantified T. cruzi prevalence in these two key reservoir species across our study area in South Carolina, US, and identified factors that may influence parasite detection. We collected whole blood from 183 raccoons and 126 opossums and used PCR to detect the presence of T. cruzi. We then used generalized linear models with parasite detection status as a binary response variable and predictor variables of land cover, distance to water, sex, season, and species. Our analysis indicated that raccoons experienced significantly higher parasite detection rates than Virginia opossums, with T. cruzi prevalence found to be 26.5% (95% confidence interval [CI], 20.0-33.8) in raccoons and 10.5% (95% CI, 5.51-17.5) in opossums. Overall, our results concur with previous studies, in that T. cruzi is established in reservoir host populations in natural areas of the southeastern US.


Assuntos
Doença de Chagas , Didelphis , Triatoma , Trypanosoma cruzi , Animais , Didelphis/parasitologia , Guaxinins/parasitologia , South Carolina/epidemiologia , Virginia , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Gambás/parasitologia
4.
J Helminthol ; 97: e58, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37476963

RESUMO

Marmosa constantiae is a species of marsupial restricted to the central portion of South America. In Brazil, it occurs in the northwestern region including five states of the Amazon, Cerrado, and Pantanal biomes. However, there is no study of the helminth fauna or helminth community structure for this marsupial. The aims of this study were to describe the species composition and to analyse the structure of the helminthic community of M. constantiae in an area of the Amazon Arc in Sinop, north of the state of Mato Grosso, Brazil. Parasites were searched in 53 specimens of this marsupial, among which 44 were infected with at least one helminth species. Parasitic helminths were counted and identified. Nine species were collected: seven nematodes, one cestode, and one acanthocephalan. The most abundant species were Gracilioxyuris agilisis, Travassostrongylus scheibelorum, Pterygodermatites sinopiensis, and Subulura eliseae. These species were the only dominant ones in the component community. No significant differences were observed in the abundance and prevalence of helminths between male and female hosts. Host body size significantly influenced helminth abundance in males. The pattern of community structure considering the infracommunities in this locality indicated more species replacement than species loss along the environmental gradient. This is the first study to report the helminth fauna and the helminth community structure of M. constantiae.


Assuntos
Helmintíase Animal , Helmintos , Marsupiais , Feminino , Masculino , Camundongos , Animais , Brasil/epidemiologia , Helmintíase Animal/epidemiologia , Helmintíase Animal/parasitologia , Gambás/parasitologia
5.
PLoS Negl Trop Dis ; 16(12): e0010974, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36534706

RESUMO

BACKGROUND: Trypanosoma cruzi, a parasitic protozoan, is endemic to the Americas and the causative agent of Chagas disease in humans. In South America, opossums facilitate transmission via infected anal gland secretions in addition to transmission via triatomine vectors. In North America, the Virginia opossum is a reservoir host for the parasite with transmission routes that are not clearly defined. The unique biology of this marsupial provides the opportunity to investigate vertical transmission in this wildlife species in situ. Our objectives were to investigate alternative routes of transmission that may facilitate spillover into other species and to determine if vertical transmission was evident. METHODOLOGY/PRINCIPAL FINDINGS: Virginia opossums were sampled at 10 trapping locations over a 10-month period in a 5-county region of north central Florida. Peripheral blood, fecal swabs, and anal gland secretions were collected from each adult individual, and peripheral blood was collected from joey opossums. Total DNA was extracted from each collected sample type, and T. cruzi infected individuals and the infecting Discrete Typing Unit (DTU) were identified using real time PCR methods. Adult Virginia opossums (n = 112) were infected with T. cruzi (51.8%, 95% CI [42.6-60.8%]) throughout the sampled period and at each location. T. cruzi DNA was found in each of the three biological sample types. Vertical transmission of T. cruzi was inferred in one litter of mother-dependent (n = 20, 5.0%, 95% CI [0.9-23.6%]) joey opossums where 2 joeys from this same litter were rtPCR positive for T. cruzi. CONCLUSIONS/SIGNIFICANCE: We inferred vertical transmission from mother to neonate which may serve to amplify the prevalence of T. cruzi in adult Virginia opossums. T. cruzi DNA was detected in the anal gland secretions of Virginia opossums. Infected anal gland secretions suggest a possible environmental route of transmission for T. cruzi via the deposition of contaminated feces and spraint at wildlife latrines. Only DTU1 was identified in the sampled population which is consistent with human autochthonous cases in the United States.


Assuntos
Doença de Chagas , Didelphis , Parasitos , Trypanosoma cruzi , Animais , Humanos , Trypanosoma cruzi/genética , Virginia , Reservatórios de Doenças , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Doença de Chagas/parasitologia , Animais Selvagens/parasitologia , Gambás/parasitologia
6.
J Parasitol ; 107(3): 388-403, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33971012

RESUMO

Two new species of Viannaia from the intestine of the North American opossums, Didelphis virginiana (Virginia opossum), and Philander opossum (gray four-eyed opossum), are described based on morphological and molecular data, through an integrative taxonomic approach. Maximum likelihood and Bayesian inference analyses for each dataset and the concatenated dataset were performed using a mitochondrial cytochrome c oxidase subunit 1 (COI) gene, and the nuclear ribosomal internal transcribed spacer region (ITS1-5.8S-ITS2). The phylogenetic analyses revealed 2 new species that occur in Mexico, one from the western state of Colima and another from the southern state of Chiapas. Our phylogenetic trees for both molecular markers and concatenated datasets yielded similar topologies with high bootstrap values and posterior probabilities. Viannaia is recovered as a monophyletic group, but the family Viannaiidae appears as non-monophyletic, due to the position of Travassostrongylus scheibelorum, similar to previous studies. Finally, the morphology of Viannaia and Hoineffia is discussed.


Assuntos
Gambás/parasitologia , Trichostrongyloidea/classificação , Tricostrongiloidíase/veterinária , Animais , Teorema de Bayes , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , DNA Intergênico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Genes Mitocondriais , Intestinos/parasitologia , Funções Verossimilhança , Masculino , México/epidemiologia , Filogenia , RNA Ribossômico 5,8S/genética , Alinhamento de Sequência , Trichostrongyloidea/anatomia & histologia , Trichostrongyloidea/genética , Trichostrongyloidea/ultraestrutura , Tricostrongiloidíase/epidemiologia , Tricostrongiloidíase/parasitologia
7.
J Med Entomol ; 58(4): 1717-1724, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-33822972

RESUMO

The genus SerratacarusGoff and Whitaker 1984, currently includes only two species, Serratacarus dietzi Goff and Whitaker, 1994 and Serratacarus lasiurus Goff and Whitaker, 1994, which were recorded on cricetid rodents from natural reserve areas of Brazil. Here, we provide a review of the morphological characters for both species and synonymize of the species Trombewingia brasiliensisGoff and Gettinger, 1991 with S. lasiurus. Additionally, we provide new locality records for both species and the first record for S. dietzi on southeastern four-eyed opossum, Philander frenatus Olfers, 1818 (Didelphimorphia, Didelphidae).


Assuntos
Trombiculidae/classificação , Animais , Brasil , Interações Hospedeiro-Parasita , Gambás/parasitologia , Trombiculidae/anatomia & histologia
8.
J Parasitol ; 106(5): 616-622, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33009554

RESUMO

The prevalence and diversity of parasitic nematodes in wildlife have been well studied for certain species, yet for others considerable gaps in knowledge exist. The parasitic nematode Dracunculus insignis infects North American wildlife, and past research on this species has led to an increased understanding of the potential host diversity and transmission of the closely related human Guinea worm, Dracunculus medinensis (which is currently the focus of a global eradication program). Many definitive hosts have been documented for D. insignis; however, the life cycle has been studied only in laboratories, and only a single phylogenetic study has been conducted on D. insignis (from Canada). The goals of the present study were to investigate the prevalence of infections with Dracunculus species among wildlife at a single site (Di-Lane plantation) in the southeastern United States, evaluate the genetic diversity of parasites at this site, and investigate potential paratenic hosts that may be involved in transmission. Over 3 yr, we sampled 228 meso-mammals, reporting an overall prevalence of infection with Dracunculus insignis of 20% (46/228). Amphibians and fish were sampled in the same geographic area as infected meso-mammals. Dracunculus insignis third-stage larvae were recovered from 2 different species of amphibians, but all fish sampled were negative. Phylogenetic analysis of the partial cytochrome c oxidase I (COI) gene showed very little diversity of Dracunculus at Di-Lane; however, we did recover a single nematode from a Virginia opossum (Didelphis virginiana) that falls outside of the D. insignis clade, more closely aligns with Dracunculus lutrae, and may represent an undescribed species. This work documents the occurrence of D. insignis in frogs, a potential transmission pathway for D. insignis at a single geographic site in nature. When applied to the global Guinea Worm Eradication Program, and Chad, Africa, in particular, this work increases our knowledge of the potential role of aquatic animals in the transmission of Dracunculus species and informs on potential intervention strategies that may be applied to the eradication of Guinea worm in Africa.


Assuntos
Animais Selvagens/parasitologia , Dracunculíase/veterinária , Dracunculus/classificação , Mamíferos/parasitologia , Anfíbios/parasitologia , Animais , Tatus/parasitologia , Chade , Coiotes/parasitologia , Dracunculíase/epidemiologia , Dracunculíase/prevenção & controle , Dracunculíase/transmissão , Dracunculus/genética , Dracunculus/crescimento & desenvolvimento , Dracunculus/isolamento & purificação , Feminino , Peixes/parasitologia , Variação Genética , Georgia/epidemiologia , Estágios do Ciclo de Vida , Masculino , Gambás/parasitologia , Filogenia , Lagoas , Prevalência , Guaxinins/parasitologia
9.
Acta Trop ; 207: 105513, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32371220

RESUMO

Worldwide, Bartonella species are known to infect a wide range of mammalian and arthropod hosts, including humans. The current study aimed to investigate the prevalence of Bartonella spp. in synanthropic mammals captured in peri-urban areas from Central-Western and Southern Brazil and their ectoparasites. For this aim, 160 mammals belonging to four species, and 218 associated arthropods were sampled. DNA was extracted and subjected to different Bartonella screening assays. Additionally, blood samples from 48 small rodents were submitted to liquid BAPGM culture followed by qPCR assay and solid culture. Two out of 55 Rattus captured in Santa Catarina state were PCR-positive for Bartonella when targeting the nuoG, 16S, and ITS loci. Sequences showed high homology with Bartonella coopersplainsensis. Conversely, all 48 small rodents, 14 capybaras and 43 opossum DNA samples from animals trapped in Mato Grosso do Sul were Bartonella negative in the HRM real time PCR assays targeting the ITS locus and gltA gene. Additionally, all mammal-associated ectoparasites showed negativity results based on HRM real time PCR assays. The present study showed, for the first time, the occurrence of B. coopersplainsensis in Brazil, shedding some light on the distribution of rats-related Bartonella in South America. In addition, the majority of rodents and marsupials were negative for Bartonella spp. Since B. coopersplainsensis reservoirs - Rattus spp. - are widely dispersed around the globe, their zoonotic potential should be further investigated.


Assuntos
Bartonella/isolamento & purificação , Mamíferos/microbiologia , Ftirápteros/microbiologia , Carrapatos/microbiologia , Animais , Bartonella/genética , DNA Bacteriano/análise , Humanos , Mamíferos/parasitologia , Marsupiais/microbiologia , Gambás/microbiologia , Gambás/parasitologia , Ratos , Roedores/microbiologia , Roedores/parasitologia
10.
Am J Trop Med Hyg ; 103(1): 428-436, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32458775

RESUMO

Trypanosoma cruzi is the etiological agent of Chagas disease that infects more than seven million people in Latin America. The parasite is transmitted by triatomine insects, of which some species are often associated with palms. The establishment of oil palm plantations (Elaeis guineensis) in the Orinoco region (Colombia) has been rapidly growing, possibly constituting a new environment for the establishment and increase in triatomine populations. In this study, the potential of Rhodnius prolixus to colonize E. guineensis plantations and maintain T. cruzi transmission was assessed. Fieldwork was conducted in two areas located in the department of Casanare for sampling E. guineensis and Attalea butyracea palms, sampling for triatomines to determine their abundance and prevalence of T. cruzi infection. To assess T. cruzi transmission potential in the area, sylvatic and domestic mammals were sampled. Results showed that palm infestation with triatomines was higher in A. butyracea than in E. guineensis palms and T. cruzi infection in triatomines varied between habitats for one study area, but was constant in the other site. Trypanosoma cruzi-infected mammals in the E. guineensis plantations were mainly generalist rodents, suggesting that these mammals could have an important role in T. cruzi transmission in plantations. In conclusion, E. guineensis plantations in the Orinoco region are suitable habitats for R. prolixus and T. cruzi transmission.


Assuntos
Arecaceae , Doença de Chagas/veterinária , Insetos Vetores/parasitologia , Rhodnius/parasitologia , Animais , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Doença de Chagas/transmissão , Quirópteros/parasitologia , Colômbia/epidemiologia , Cães/parasitologia , Florestas , Gambás/parasitologia , Óleo de Palmeira , Roedores/parasitologia , Sus scrofa/parasitologia , Trypanosoma cruzi
11.
Parasitol Res ; 119(2): 675-682, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31901995

RESUMO

Sarcocystis neurona is the main agent associated with equine protozoal myeloencephalitis (EPM). Apart from horses, S. neurona has been occasionally described causing neurologic disease in several other terrestrial animals as well as mortality in marine mammals. Herein, we describe the clinical, pathological, and molecular findings of a fatal case of S. neurona-associated meningoencephalitis in a domestic cat. The causing agent was analyzed by multilocus genotyping, confirming the presence of S. neurona DNA in the tissue samples of the affected animal. Significant molecular differences were found in relation to S. neurona isolates detected in other regions of the Americas. In addition, the parasite was identical to Sarcocystis sp. identified in opossum sporocysts in Brazil at molecular level, which suggests that transmission of. S. neurona in Brazil might involve variants of the parasite different from those found elsewhere in the Americas. Studies including more samples of S. neurona would be required to test this hypothesis, as well as to assess the impact of this diversity.


Assuntos
Doenças do Gato/parasitologia , Infecções Protozoárias do Sistema Nervoso Central/veterinária , Encefalomielite/parasitologia , Meningoencefalite/parasitologia , Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Animais , Brasil , Gatos , DNA de Protozoário/genética , Doenças dos Cavalos/parasitologia , Cavalos , Gambás/parasitologia , Sarcocystis/genética
12.
Parasitol Res ; 119(1): 97-104, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31735993

RESUMO

Blastocystis spp. are common intestinal parasites found worldwide in humans and a wide range of animals. They exhibit extensive genetic diversity; currently, 17 subtypes (STs) and some groups called non-mammalian and avian STs (NMASTs) have been proposed. In addition, a large variety of animals have been reported as hosts of the parasite, and new hosts and STs are still being described. In this study, Blastocystis infection of wild animals in two sylvatic areas of Mexico was surveyed. Of one hundred twenty-four fecal samples, six were positive for Blastocystis: specifically, one sample from an opossum, one sample from a bat, and four samples from different species of rodents. ST4, ST17, and nucleotide sequences similar to Blastocystis lapemi were identified based on SSU rDNA sequences. To our knowledge, this is the first report to investigate species poorly or not previously evaluated for Blastocystis infection. Mammals having different niches and geographical distribution were infected with similar genetic type of Blastocystis, so that we suggest that local water or food sources could play an important role in Blastocystis transmission and ST maintenance in wild animals. Additionally, there are STs with scarce genetic variation, suggesting that they could be highly adapted to their hosts. These data contribute to our understanding of the host range and genetic diversity of Blastocystis.


Assuntos
Infecções por Blastocystis/veterinária , Blastocystis/classificação , Blastocystis/genética , Especificidade de Hospedeiro/fisiologia , Animais , Blastocystis/isolamento & purificação , Quirópteros/parasitologia , DNA de Protozoário/genética , DNA Ribossômico/genética , Fezes/parasitologia , Variação Genética , Genótipo , Humanos , México , Tipagem Molecular , Gambás/parasitologia , Roedores/parasitologia
13.
J Parasitol ; 105(4): 624-629, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31418650

RESUMO

Studies on helminth communities associated with didelphids are scarce; the majority of works have focused at taxonomic level. To increase the ecological knowledge of these host-parasite associations, during March (dry season) of 3 consecutive years (2013-2015) a total of 49 adults of the gray four-eyed opossum (Philander opossum) was collected in the Neotropical portion of Mexico (Agua Fría, Chiapas State) and examined for helminths. The main objectives of this study were to describe the infra- and component communities of helminths associated with P. opossum and to compare the helminth fauna of the Mexican population of this host species with those studied in French Guiana and in other Mexican terrestrial didelphids. The helminthological record of this host consisted of 12 species: 7 taxa of Nematoda, 3 of Trematoda, 1 Cestoda, and 1 Acanthocephala. Eight of the 12 taxa have been previously recorded in Didelphidae and 4 represent accidental infections ( Glossocercus sp., Stomylotrema vicarium, Spirura mexicana and Acanthocephala gen. sp.). Diet of hosts is the main structuring factor of the communities (92% of the helminth species were recruited through ingestion). Forty-eight hosts were parasitized by at least 1 helminth species; Rhopalias coronatus was the most prevalent and abundant species in the hosts sampled. No significant differences were found in global prevalence among the helminth species present in all samplings, considering host sex and year. The dominance exerted by R. coronatus led to low values of evenness and diversity at both community levels. No significant differences were observed in composition of helminth species among the 3 sampling years regarding sex. The results of our study showed changes in helminth abundance at infracommunity level; during the first sampling these changes are explained by species with direct life cycle ( Viannaia sp. and Cruzia tentaculata), whereas in last 2 surveys the explanation can be attributed to species with heteroxenous life cycles (particularly R. coronatus, Duboisiella proloba, and Turgida turgida). Thirty-three percent of the helminth species recorded in P. opossum in Agua Fría is shared with the other 2 terrestrial species of didelphids sampled in different sites of Mexico: Didelphis marsupialis and Didelphis virginiana. In contrast, samples from French Guiana and Agua Fría, differ in terms of helminth fauna, confirming that the helminth communities of opossum species inhabiting the same locality show higher levels of taxonomic similarity than communities of conspecific marsupials allopatrically distributed.


Assuntos
Helmintíase Animal/parasitologia , Helmintos/classificação , Gambás/parasitologia , Animais , Feminino , Helmintíase Animal/epidemiologia , Masculino , México/epidemiologia
14.
Parasite ; 26: 50, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31432779

RESUMO

Tlacuatzoxyuris simpsoni n. gen. n. sp. is described from the cecum of the gray opossum, Tlacuatzin canescens, a species endemic to the deciduous dry forest of Mexico. The digestive tracts of four specimens were examined for parasites; three of these were archived in the American Museum of Natural History and one was a live capture. Relative to the other four monotypic genera of pinworms known to infect opossums, the new genus is diagnosed on the basis of a round cephalic plate with a semicircular stoma surrounded by a rim. In addition, males feature a prominent cephalic vesicle not fully developed in females, accounting for sexual dimorphism. The new species includes small worms that feature a conspicuous, not reticulated cephalic vesicle and semicircular stoma and lateral alae with two crests. In addition, the postcloacal cuticle of males features a small area with ornamentation between cloaca and submedial papillae. Finally, both spicule and gubernaculum are relatively short. Although the eggs of Tlacuatzoxyuris n. gen. are unknown, the conspicuous differences in traits used in the diagnosis of genera prompted us to propose a new genus for the new species. This is the first species of Oxyuridae reported in mouse opossums outside South America, and the fifth species of the family occurring in didelphimorph marsupials. This is an example of the usefulness of documenting the diversity of parasites associated with this unique clade of mammals through the examination of preserved tissues.


Assuntos
Enterobíase/veterinária , Enterobius/classificação , Enterobius/isolamento & purificação , Gambás/parasitologia , Animais , Ceco/parasitologia , Enterobius/anatomia & histologia , Feminino , Masculino
15.
Parasit Vectors ; 12(1): 308, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221188

RESUMO

BACKGROUND: The heterogeneity of Trypanosoma cruzi infection rates among triatomines insects and animal reservoirs has been studied in independent studies, but little information has been systematised to allow pooled and comparative estimates. Unravelling the main patterns of this heterogeneity could contribute to a further understanding of T. cruzi transmission in Colombia. METHODS: A systematic search was conducted in PubMed, Medline, LILACS, Embase, Web of Knowledge, Google Scholar and secondary sources with no filters of language or time and until April 2018. Based on selection criteria, all relevant studies reporting T. cruzi infection rates in reservoirs or triatomines were chosen. For pooled analyses, a random effects model for binomial distribution was used. Heterogeneity among studies is reported as I2. Subgroup analyses included: taxonomic classification, ecotope and diagnostic methods. Publication bias and sensitivity analyses were performed. RESULTS: Overall, 39 studies reporting infection rates in Colombia were found (22 for potential reservoirs and 28 for triatomine insects) for a total sample of 22,838 potential animals and 11,307 triatomines evaluated for T. cruzi infection. We have found evidence of 38/71 different animal species as potential T. cruzi reservoirs and 14/18 species as triatomine vectors for T. cruzi. Among animals, the species with the highest pooled prevalence were opossum (Didelphis marsupialis) with 48.0% (95% CI: 26-71%; I2 = 88%, τ2 = 0.07, P < 0.01) and domestic dog (Canis lupus familiaris) with 22.0% (95% CI: 4-48%; I2 = 96%, τ2 = 0.01, P < 0.01). Among triatomines, the highest prevalence was found for Triatoma maculata in the peridomestic ecotope (68.0%, 95% CI: 62-74%; I2 = 0%, τ2 = 0, P < 0.0001), followed by Rhodnius prolixus (62.0%, 95% CI: 38-84%; I2 = 95%, τ2 = 0.05, P < 0.01) and Rhodnius pallescens (54.0%, 95% CI: 37-71%; I2 = 86%, τ2 = 0.035, P < 0.01) in the sylvatic ecotope. CONCLUSIONS: To our knowledge, this is the first systematic and quantitative analyses of triatomine insects and potential animal reservoirs for T. cruzi infection in Colombia. The results highlight a marked heterogeneity between species and provide initial estimates of infection rates heterogeneity.


Assuntos
Doença de Chagas/veterinária , Reservatórios de Doenças/veterinária , Insetos Vetores/parasitologia , Triatoma/parasitologia , Animais , Animais Domésticos/parasitologia , Distribuição Binomial , Doença de Chagas/epidemiologia , Doença de Chagas/transmissão , Colômbia/epidemiologia , Reservatórios de Doenças/parasitologia , Cães/parasitologia , Genótipo , Gambás/parasitologia , Prevalência , Rhodnius/parasitologia , Trypanosoma cruzi
16.
J Parasitol ; 105(2): 371-378, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31033388

RESUMO

Sarcocystis neurona is a ubiquitous parasite in the eastern United States, which is the principal causative agent in the neurologic disorder equine protozoal myeloencephalitis (EPM). While much is known about this protozoa's life cycle in its natural host, the opossum (Didelphis virginiana), little is known of how it acts in the aberrant equine host, which displays a high incidence of exposure with a relatively low rate of morbidity. For this study, we employed the popular interferon gamma knockout mouse model to determine the potential for recrudescence of S. neurona infection after treatment with the anticoccidial drug diclazuril. Mice were infected with S. neurona merozoites, and 7-days post-infection (DPI) they were treated with diclazuril for 30 or 60 days or not treated at all. All infected non-treated mice developed neurologic signs consistent with S. neurona infection within 30 DPI. All diclazuril-treated infected mice remained clinically normal while on treatment but developed neurologic signs within 60 days of treatment cessation. Histological examination of cerebella from all infected mice demonstrated characteristic lesions of S. neurona infection, regardless of treatment status. Cerebellar samples collected from infected treated mice, displaying neurologic signs, produced viable S. neurona in culture. However, cerebellar samples collected from infected and neurologically normal mice at the end of a 30-day treatment period did not produce viable S. neurona in culture. Analysis of the humoral immune response in infected mice showed that during treatment IgM antibody production decreased, suggesting the organism was sequestered from immune surveillance. The cessation of treatment and subsequent development of neurologic disease resulted in increased IgM antibody production, suggesting recognition by the immune system at that time. Based on the study results the authors propose that diclazuril was able to inhibit the replication and migration of S. neurona but not fully eliminate the parasite, suggesting recrudescence of infection after treatment is possible.


Assuntos
Coccidiostáticos/uso terapêutico , Encefalomielite/parasitologia , Nitrilas/uso terapêutico , Sarcocystis/patogenicidade , Sarcocistose/parasitologia , Triazinas/uso terapêutico , Animais , Encéfalo/parasitologia , Cerebelo/parasitologia , Cerebelo/patologia , Chlorocebus aethiops , Coccidiostáticos/farmacologia , Encefalomielite/tratamento farmacológico , Ensaio de Imunoadsorção Enzimática , Fezes/parasitologia , Feminino , Imunoglobulinas/sangue , Imuno-Histoquímica , Interferon gama/genética , Masculino , Camundongos , Camundongos Knockout , Nitrilas/farmacologia , Gambás/parasitologia , Recidiva , Sarcocystis/efeitos dos fármacos , Sarcocistose/tratamento farmacológico , Triazinas/farmacologia , Células Vero
17.
Exp Parasitol ; 197: 68-75, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30439347

RESUMO

BACKGROUND: In recent decades some outbreaks of food-borne acute Chagas disease (ACD) in humans were identified by clinical and epidemiological characterization after association through the ingestion of açaí pulp probably contaminated with Trypanosoma cruzi. Whereas Belém and Abaetetuba stood out as important risk regions for disease transmission, the importance of Rhodnius pictipes, and Philander opossum for the biological cycle of T. cruzi, and data from agribusiness market of açaí, to study T. cruzi from vector and reservoir of the Brazilian Amazon region is critical for this context. Thus, the purpose of this study was to verify the infective capacity and the virulence of T. cruzi in açaí pulp from vector and reservoir at Pará State experimentally. METHODS: 105T. cruzi I in in natura açaí pulp from Belém at Pará State, at room temperature, after forced sieving, by intraperitoneal, gavage or oral route of inoculation in B6.129S7Rag1-/-tmMom/J Unib allowed food-borne ACD analysis using common light microscopy. PRINCIPAL FINDINGS: T. cruzi in in natura açaí pulp from R. pictipes (Val-De-Cans Forest, Belém, and Ajuaí River, Abaetetuba, Pará), and P. opossum (Combu Island, Belém, Pará) caused ACD and death between 17 and 52 days after experimental infections in murine immunodeficient hosts. CONCLUSIONS: T. cruzi from different sources and locations at Pará State in in natura açaí pulp retained its infective capacity and virulence, and can cause new outbreaks of ACD by oral transmission. Additionally, quality basic education will facilitate efficient hygiene practices throughout the açaí productive chain can eradicate food-borne ACD in the coming decades.


Assuntos
Doença de Chagas/transmissão , Euterpe/parasitologia , Parasitologia de Alimentos , Doenças Transmitidas por Alimentos/parasitologia , Trypanosoma cruzi/patogenicidade , Doença Aguda , Animais , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Reservatórios de Doenças/parasitologia , Vetores de Doenças , Feminino , Doenças Transmitidas por Alimentos/epidemiologia , Insetos Vetores/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos , Gambás/parasitologia , Parasitemia/epidemiologia , Parasitemia/mortalidade , Rhodnius/parasitologia , Virulência
18.
Parasit Vectors ; 11(1): 502, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30189896

RESUMO

Trypanosoma cruzi (Kinetoplastea: Trypanosomatidae) infects all tissues of its hosts, which along with humans, include hundreds of mammalian species in the Americas. The epidemiology of T. cruzi has been changing in that currently the majority of the cases and/or outbreaks of Chagas disease occur by the ingestion of comestibles contaminated by T. cruzi metacyclic forms. These cases/outbreaks occur in distinct regional scenarios, mainly in the Amazon biome and are related to the local interaction mode of humans with their surroundings, as well as with the overall local ecological peculiarities. As trypanosomiasis caused by T. cruzi is primarily a zoonosis, understanding the variables that influences its transmission in the wild as well as the role played by the extant fauna in the maintenance of the parasite, is critical in establishing control measures. Here, we present the results of our studies of T. cruzi infection of free ranging wild mammalian fauna in the five biomes of Brazil, a country of continental dimensions. From 1992 up to 2017, we examined a total of 6587 free-ranging non-volant wild mammal specimens. Our studies found that 17% of mammals were seropositive and 8% of all animals displayed positive hemocultures indicative of high parasitemia and, consequently, of infectivity potential. We observed that opossums, mainly Philander spp. and Didelphis spp., the coati Nasua nasua, the capuchin monkey Sapajus libidinosus and the golden lion tamarin Leontopithecus rosalia, were mammal taxa that demonstrated higher rates of positive hemocultures. Additionally, Didelphis spp. demonstrated to be a competent bioaccumulator of TcI diversity. Chiroptera were distinguished for hosting the greatest diversity of species and genotypes of Trypanosoma spp. Additionally the observation of the higher host range of some Trypanosoma spp., shows the need to reassess the ecology of representatives of the taxon. Altogether, our results showed that each locality, may display distinct enzootiological and epidemiological scenarios that must be taken into account when it comes to establishing control and/or clarification campaigns of the local population.


Assuntos
Animais Selvagens/parasitologia , Doença de Chagas/veterinária , Reservatórios de Doenças/parasitologia , Parasitemia/veterinária , Trypanosoma cruzi/isolamento & purificação , Tripanossomíase/veterinária , Animais , Animais Selvagens/imunologia , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Doença de Chagas/transmissão , Quirópteros/imunologia , Quirópteros/parasitologia , Ecossistema , Humanos , Mamíferos/imunologia , Mamíferos/parasitologia , Gambás/imunologia , Gambás/parasitologia , Parasitemia/epidemiologia , Parasitemia/imunologia , Trypanosoma cruzi/imunologia , Trypanosoma cruzi/fisiologia , Tripanossomíase/epidemiologia , Tripanossomíase/parasitologia , Tripanossomíase/transmissão
19.
Med Vet Entomol ; 32(4): 462-472, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30027674

RESUMO

The flea genus Neotyphloceras Rothschild (Siphonaptera: Ctenophthalmidae) includes five species and two subspecies distributed from Venezuela to southern Chile and Argentina. Only Neotyphloceras crassispina hemisus Jordan has been registered in Bolivia. The present study examines species of Neotyphloceras collected in Bolivian localities in the Departments of La Paz, Cochabamba and Tarija, and describes the morphology of the modified abdominal segments in males and females of Neotyphloceras rosenbergi Rothschild on the basis of type material and specimens collected from Tarija. A new species, Neotyphloceras boliviensis n. sp., is described and new host associations are reported for N. rosenbergi, Neotyphloceras crassispina crassispina and N. crassispina hemisus. Neotyphloceras c. crassispina and N. rosenbergi are reported for the first time in Bolivia. The distribution of N. rosenbergi is extended 1600 km to the south. Given the potential medical and veterinary significance of fleas as disease vectors, and considering that in the Departments of La Paz and Tarija several human cases of plague have been reported, and species of flea have been identified as main vectors of these diseases, the new records of fleas in Bolivia reported herein may be useful for epidemiological studies on flea-borne diseases.


Assuntos
Infestações por Pulgas/veterinária , Gambás/parasitologia , Ratos/parasitologia , Doenças dos Roedores/parasitologia , Sigmodontinae/parasitologia , Sifonápteros/classificação , Animais , Bolívia/epidemiologia , Feminino , Infestações por Pulgas/epidemiologia , Infestações por Pulgas/parasitologia , Masculino , Doenças dos Roedores/epidemiologia , Sifonápteros/anatomia & histologia
20.
Exp Parasitol ; 188: 42-49, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29522766

RESUMO

In a previous study in Brazil, six isolates of Sarcocystis spp. recovered from budgerigars fed sporocysts excreted by opossums of the genus Didelphis were characterized by means of sequencing fragments of gene coding cytochrome B (CYTB), internal transcribed spacer 1 (ITS1), and surface antigen genes (SAG2, SAG3 and SAG4). The isolates shared identical ITS1 and CYTB sequences, but differed at SAG2, SAG3 and SAG4: three allele variants of SAG2, 3 allele variants of SAG3 and 2 allele variants of SAG4 were encountered in three multilocus genotypes (MLGs) (MLG1, MLG2, and MLG3). At ITS1 and CYTB, all the isolates from budgerigars were identical to the Sarcocystis falcatula-like isolate 59-2016-RS-BR that was detected in a barefaced ibis (Phimosus infuscatus) causing necrotizing meningoencephalitis in Brazil. At ITS1 locus, all the above isolates were clearly distinct from Sarcocystis neurona, Sarcocystis falcatula, Sarcocystis lindsayi, and Sarcocystis speeri, the four known species of Sarcocystis that use opossums of the genus Didelphis as definitive hosts. Here, we replicated the experiment above to identify additional MLGs or other species of Sarcocystis. Fifteen budgerigars were experimentally infected with sporocysts of Sarcocystis spp. from 12 opossums of the genus Didelphis. All the birds died 9-19 days after infection and tissue samples containing merozoites and schizonts of Sarcocystis spp. were recovered. Fractions of sequences coding for 18S ribosomal RNA gene (18S), CYTB, ITS1, SAG2, SAG3 and SAG4 were PCR amplified and sequenced from the infected lungs. In addition, fractions of 18S, SAG2, SAG3 and SAG4 were sequenced from the isolate 59-2016-RS-BR and fractions of 18S were sequenced from the six isolates from budgerigars described above. From the results, all the isolates shared identical 18S, ITS1 and CYTB sequences. Among the 15 new isolates from budgerigars, three allele variants of SAG2, 3 allele variants of SAG3 and 2 allele variants of SAG4 were encountered in five MLGs, of which four were novel (MLG1, MLG4, MLG5, MLG6 and MLG7). Isolate 59-2016-RS-BR was assigned to an eighth MLG (MLG8). Molecular data pointed that Sarcocystis assigned to MLGs 1 to 8 are variants of the same species, but the SAG-based trees of the isolates conflicted, which supports genetic admixture among them. The sarcocystinae studied have high diversity of SAG alleles per locus and the correlation of such an abundant variety of SAG alleles to host specificity and pathogenicity needs to be assessed. Remains to be elucidated if the parasites studied here and S. falcatula are variants of the same species that have diverged to the point of possessing differences at ITS1 level, but that are still capable of exchanging genes.


Assuntos
Alelos , Antígenos de Protozoários/genética , Doenças das Aves/parasitologia , Gambás/parasitologia , Sarcocystis/genética , Sarcocistose/veterinária , Animais , Antígenos de Superfície/genética , Evolução Biológica , Aves , Encéfalo/parasitologia , Brasil , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Variação Genética/genética , Pulmão/parasitologia , Melopsittacus , Meningoencefalite/parasitologia , Meningoencefalite/veterinária , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase/veterinária , Guaxinins/parasitologia , Sarcocystis/classificação , Sarcocystis/imunologia , Sarcocystis/isolamento & purificação , Sarcocistose/parasitologia , Análise de Sequência de DNA/veterinária
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