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1.
Parasitol Res ; 120(2): 383-394, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33447885

RESUMO

Ticks are considered the second most important vectors of pathogens worldwide, after mosquitoes. This study provides a systematic review of vector-host relationships between ticks and mammals (domestic and wild) and consolidates information from studies conducted in Colombia between 1911 and 2020. Using the PRISMA method, 71 scientific articles containing records for 51 tick species (Argasidae and Ixodidae) associated with mammals are reported. The existing information on tick-mammal associations in Colombia is scarce, fragmented, or very old. Moreover, 213 specimens were assessed based on morphological and molecular analyses, which allowed confirming eight tick species associated with mammals: Amblyomma calcaratum, Amblyomma dissimile, Amblyomma mixtum, Amblyomma nodosum, Amblyomma ovale, Amblyomma varium, Ixodes luciae, and Ixodes tropicalis. Several tick species are molecularly confirmed for Colombia and nine new relationships between ticks and mammals are reported. This research compiles and confirms important records of tick-mammal associations in Colombia.


Assuntos
Vetores Artrópodes/fisiologia , Mamíferos/parasitologia , Infestações por Carrapato/veterinária , Carrapatos/fisiologia , Animais , Argasidae/classificação , Argasidae/genética , Argasidae/fisiologia , Vetores Artrópodes/classificação , Vetores Artrópodes/genética , Colômbia , Interações Hospedeiro-Parasita , Ixodidae/classificação , Ixodidae/genética , Ixodidae/fisiologia , Infestações por Carrapato/parasitologia , Carrapatos/classificação , Carrapatos/genética
2.
Parasitol Res ; 120(3): 963-970, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33501587

RESUMO

Capillariidae is a group of nematode parasites of vertebrates with a complex taxonomy. The structure of the eggshell, which was indicated as the most important characteristic for identification of genus or species through eggs, is very diverse among genera. The visualization and characterization of eggshell by light microscopy (LM) are a challenging task since different planes of the egg surface are needed. Nevertheless, categories of eggshell ornamentation were proposed by LM: smooth, punctuated, reticulated type I, and reticulated type II. The present study aimed to characterize the eggshell structure of Capillariidae species, parasites of mammals and avians, deposited in a helminthological collection using scanning electron microscopy (SEM). Institutional Biological Collections are taxonomic repositories of specimens described and strictly identified at the species level by systematics specialists. SEM eggshell images were obtained from 12 species belonging to 5 genera (Aonchotheca, Baruscapillaria, Capillaria, Echinocoleus, Eucoleus) and compared to their respective LM images. Eggshell patterns observed using SEM were associated categories of eggshell ornamentation previously proposed by LM images. The SEM data indicate that eggshell categories are not in agreement with capillariid genera or sites of infection. However, the study provides previously unknown SEM eggshell information from curated species, which contributes with a specific and supplementary taxonomic feature at the species level of Capillariidae.


Assuntos
Nematoides/ultraestrutura , Infecções por Nematoides/veterinária , Óvulo/ultraestrutura , Animais , Aves/parasitologia , Mamíferos/parasitologia , Microscopia Eletrônica de Varredura , Nematoides/classificação , Infecções por Nematoides/parasitologia , Especificidade da Espécie
3.
Appl Environ Microbiol ; 87(7)2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33514519

RESUMO

The composition of tick microbiomes varies both within and among tick species. Whether this variation is intrinsic (related to tick characteristics) or extrinsic (related to vertebrate host and habitat) is poorly understood but important, as microbiota can influence the reproductive success and vector competence of ticks. We aimed to uncover what intrinsic and extrinsic factors best explain the microbial composition and taxon richness of 11 species of neotropical ticks collected from eight species of small mammals in 18 forest fragments across central Panama. Microbial richness varied among tick species, life stages, and collection sites but was not related to host blood source. Microbiome composition was best explained by tick life stage, with bacterial assemblages of larvae being a subset of those of nymphs. Collection site explained most of the bacterial taxa with differential abundance across intrinsic and extrinsic factors. Francisella and Rickettsia were highly prevalent, but their proportional abundance differed greatly among tick species, and we found both positive and negative cooccurrence between members of these two genera. Other tick endosymbionts (e.g., Coxiella and Rickettsiella) were associated with specific tick species. In addition, we detected Anaplasma and Bartonella in several tick species. Our results indicate that the microbial composition and richness of neotropical ticks are principally related to intrinsic factors (tick species and life stage) and collection site. Taken together, our analysis informs how tick microbiomes are structured and can help anchor our understanding of tick microbiomes from tropical environments more broadly.IMPORTANCE Blood-feeding arthropod microbiomes often play important roles in disease transmission, yet the factors that structure tick microbial communities in the Neotropics are unknown. Utilizing ticks collected from live animals in neotropical forest fragments, this study teases apart the contributions of intrinsic and extrinsic tick-associated factors on tick microbial composition as well as which specific microbes contribute to differences across tick species, tick life stages, the mammals they fed on, and the locations from where they were sampled. Furthermore, this study provides revelations of how notable tick-associated bacterial genera are interacting with other tick-associated microbes as well as the forest animals they encounter.


Assuntos
Bactérias/isolamento & purificação , Microbiota , Carrapatos/microbiologia , Animais , Florestas , Larva/crescimento & desenvolvimento , Larva/microbiologia , Mamíferos/parasitologia , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Panamá , Carrapatos/crescimento & desenvolvimento
4.
Nat Commun ; 11(1): 6411, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33339816

RESUMO

Over 250 million people suffer from schistosomiasis, a tropical disease caused by parasitic flatworms known as schistosomes. Humans become infected by free-swimming, water-borne larvae, which penetrate the skin. The earliest intra-mammalian stage, called the schistosomulum, undergoes a series of developmental transitions. These changes are critical for the parasite to adapt to its new environment as it navigates through host tissues to reach its niche, where it will grow to reproductive maturity. Unravelling the mechanisms that drive intra-mammalian development requires knowledge of the spatial organisation and transcriptional dynamics of different cell types that comprise the schistomulum body. To fill these important knowledge gaps, we perform single-cell RNA sequencing on two-day old schistosomula of Schistosoma mansoni. We identify likely gene expression profiles for muscle, nervous system, tegument, oesophageal gland, parenchymal/primordial gut cells, and stem cells. In addition, we validate cell markers for all these clusters by in situ hybridisation in schistosomula and adult parasites. Taken together, this study provides a comprehensive cell-type atlas for the early intra-mammalian stage of this devastating metazoan parasite.


Assuntos
Mamíferos/parasitologia , Parasitos/citologia , Parasitos/crescimento & desenvolvimento , Schistosoma mansoni/citologia , Schistosoma mansoni/crescimento & desenvolvimento , Análise de Célula Única , Animais , Esôfago/metabolismo , Éxons/genética , Regulação da Expressão Gênica , Humanos , Células Musculares/metabolismo , Sistema Nervoso/citologia , Neurônios/citologia , Parasitos/genética , Schistosoma mansoni/genética , Células-Tronco/citologia , Células-Tronco/metabolismo , Transcrição Genética
5.
Nature ; 584(7821): 398-402, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32759999

RESUMO

Land use change-for example, the conversion of natural habitats to agricultural or urban ecosystems-is widely recognized to influence the risk and emergence of zoonotic disease in humans1,2. However, whether such changes in risk are underpinned by predictable ecological changes remains unclear. It has been suggested that habitat disturbance might cause predictable changes in the local diversity and taxonomic composition of potential reservoir hosts, owing to systematic, trait-mediated differences in species resilience to human pressures3,4. Here we analyse 6,801 ecological assemblages and 376 host species worldwide, controlling for research effort, and show that land use has global and systematic effects on local zoonotic host communities. Known wildlife hosts of human-shared pathogens and parasites overall comprise a greater proportion of local species richness (18-72% higher) and total abundance (21-144% higher) in sites under substantial human use (secondary, agricultural and urban ecosystems) compared with nearby undisturbed habitats. The magnitude of this effect varies taxonomically and is strongest for rodent, bat and passerine bird zoonotic host species, which may be one factor that underpins the global importance of these taxa as zoonotic reservoirs. We further show that mammal species that harbour more pathogens overall (either human-shared or non-human-shared) are more likely to occur in human-managed ecosystems, suggesting that these trends may be mediated by ecological or life-history traits that influence both host status and tolerance to human disturbance5,6. Our results suggest that global changes in the mode and the intensity of land use are creating expanding hazardous interfaces between people, livestock and wildlife reservoirs of zoonotic disease.


Assuntos
Biodiversidade , Especificidade de Hospedeiro , Zoonoses/microbiologia , Zoonoses/parasitologia , Zoonoses/virologia , Animais , Aves/microbiologia , Aves/parasitologia , Aves/virologia , Humanos , Mamíferos/microbiologia , Mamíferos/parasitologia , Mamíferos/virologia , Especificidade da Espécie , Zoonoses/transmissão
6.
Trends Parasitol ; 36(8): 668-676, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32540194

RESUMO

Understanding the origin of sex differences in lifespan and aging patterns remains a salient challenge in both biogerontology and evolutionary biology. Different factors have been studied but the potential influence of pathogens has never been investigated. Sex differences, especially in hormones and resource allocation, generate a differential response to pathogens and thereby shape sex differences in lifespan or aging. We provide an integrative framework linking host pathogenic environment with both sex-specific selections on immune performance and mortality trajectories. We propose future directions to fill existing knowledge gaps about mechanisms that link sex differences, not only to exposition and sensitivity to pathogens, but also to mortality patterns, whilst emphasizing the urgent need to consider the role of sex in medicine.


Assuntos
Envelhecimento/fisiologia , Interações Hospedeiro-Parasita/fisiologia , Mamíferos/parasitologia , Doenças Parasitárias/epidemiologia , Envelhecimento/imunologia , Animais , Evolução Biológica , Interações Hospedeiro-Parasita/imunologia , Humanos , Longevidade , Mamíferos/imunologia , Doenças Parasitárias/parasitologia , Fatores Sexuais
7.
Parasitol Res ; 119(8): 2679-2686, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32588173

RESUMO

Rodents and other micromammals constitute important reservoirs of infectious diseases; their role in the life cycle of apicomplexan parasites such as Toxoplasma gondii, Neospora caninum, and Sarcocystis spp. still needs clarification. In the present study, we analyzed by PCR and Sanger sequencing methods the presence of specific parasite DNA within brain and heart tissues of 313 individuals of five synanthropic small mammal species (Apodemus sylvaticus, Mus spretus, M. musculus, Rattus rattus, and Crocidura russula) collected in Barcelona metropolitan area (NE Spain). In addition, PCR-RFLP and microsatellites were also used as tools for genotypic characterization of T. gondii and N. caninum, respectively. Specific DNA of T. gondii, N. caninum, and Sarcocystis spp. was detected in 0.3% (n = 1), 1.3% (n = 4), and 3.8% (n = 12) of the animals, respectively. No mixed infections were observed. Crocidura russula stood out as the main host for Sarcocystis spp. Toxoplasma gondii-specific DNA detected in a house rat was genetically characterized by PCR-RFLP, presenting type II and III alleles (SAG1 [II], SAG3 [II], GRA6 [II], c22-8 [III], Apico [III]). Also, unsuccessful DNA sequencing and microsatellite typing were attempted in N. caninum-positive samples, which suggested a lack of PCR specificity and open avenues to speculate the host competence of rodents for N. caninum. Likewise, Sarcocystis spp. identity was studied by alignment and phylogenetic analyses of cox1 and 28S rRNA sequences from the 14 positive samples. It resulted in at least three unknown organisms closely similar (95.7-100% cox1-sequence homology) to Sarcocystis pantherophisi from the Eastern rat snake (Pantherophis alleghaniensis) (KU891603), suggesting together with 28S rRNA sequences analyses, three Sarcocystis sp. with a life cycle conformed by rodents as intermediate host (IH) and snakes as definitive hosts (DH) infecting the periurban micromammals surveyed. Prevalence figures found in this first survey carried out in Spain agree with other international studies focused on periurban areas. Further surveys should be conducted in farms and their surroundings in order to unravel the role of wild micromammals in the epidemiology of such protozoan parasites affecting our livestock, and therefore human population.


Assuntos
Coccidiose/veterinária , Mamíferos/parasitologia , Infecções Protozoárias em Animais/parasitologia , Sarcocystidae/genética , Animais , Coccidiose/epidemiologia , Coccidiose/parasitologia , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Genótipo , Mamíferos/classificação , Encistamento de Parasitas , Filogenia , Infecções Protozoárias em Animais/epidemiologia , Sarcocystidae/classificação , Sarcocystidae/isolamento & purificação , Espanha/epidemiologia
8.
Proc Biol Sci ; 287(1927): 20200397, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32396800

RESUMO

Rates of urbanization are increasing globally, with consequences for the dynamics of parasites and their wildlife hosts. A small subset of mammal species have the dietary and behavioural flexibility to survive in urban settings. The changes that characterize urban ecology-including landscape transformation, modified diets and shifts in community composition-can either increase or decrease susceptibility and exposure to parasites. We used a meta-analytic approach to systematically assess differences in endoparasitism between mammals in urban and non-urban habitats. Parasite prevalence estimates in matched urban and non-urban mammal populations from 33 species were compiled from 46 published studies, and an overall effect of urban habitation on parasitism was derived after controlling for study and parasite genus. Parasite life cycle type and host order were investigated as moderators of the effect sizes. We found that parasites with complex life cycles were less prevalent in urban carnivore and primate populations than in non-urban populations. However, we found no difference in urban and non-urban prevalence for parasites in rodent and marsupial hosts, or differences in prevalence for parasites with simple life cycles in any host taxa. Our findings therefore suggest the disruption of some parasite transmission cycles in the urban ecological community.


Assuntos
Ecossistema , Mamíferos/parasitologia , Animais , Interações Hospedeiro-Parasita , Parasitos
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.
Parasitol Res ; 119(7): 2093-2104, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32462294

RESUMO

We studied patterns of ectoparasite species turnover and pairwise ectoparasite-host interactions across space and time in fleas and mites harboured by small mammals using a novel metric, zeta diversity (similarity between multiple communities). We asked whether the zeta diversity of parasites and their interactions with hosts follow a similar spatial or temporal trend. We found substantial differences in some (zeta decline and retention rate) but not in other (zeta decay) spatial patterns of zeta diversity between species and interactions, whereas the differences between the patterns of the temporal species versus interaction zeta diversity occurred to a much lesser extent. In particular, the parametric form of zeta decline suggested that the distribution of ectoparasite species across localities is driven mainly by niche-based processes, whereas the spatial distribution of flea-host and mite-host interactions is predominantly stochastic. We also found much stronger variation in the number of shared species and interactions over space than over time. Parasite community composition, in terms of species, appeared to be much more temporally stable than that in terms of parasite-host interactions. The parametric form of temporal zeta decline indicated that both parasite communities and parasite-host networks are assembled over time via niche-based processes.


Assuntos
Infestações por Pulgas/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Mamíferos/parasitologia , Infestações por Ácaros/parasitologia , Distribuição Animal , Animais , Infestações por Pulgas/epidemiologia , Especificidade de Hospedeiro , Infestações por Ácaros/epidemiologia , Ácaros , Sifonápteros , Fatores de Tempo
11.
Exp Appl Acarol ; 81(1): 117-134, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32300917

RESUMO

The present work aimed to analyze the ectoparasite-host interaction network and possible differences of this interaction related to two seasonal periods and host sex. During November 2016 and July 2017, non-flying small mammals were captured in 17 forest fragments located in the southern portion of the Amazon biome. We captured 96 individuals belonging to 10 host species that were parasitized with a total of 3668 ectoparasites. Overall, we identified 24 ectoparasite taxa belonging to the mite and insect groups Ixodida (ticks), Mesostigmata, Sarcoptiformes, Trombidiformes (mites), Phthiraptera (lice), and Siphonaptera (fleas). The interaction network between all ectoparasites and hosts showed significant deviation from random, with moderately high specialization index (H2' = 0.80). There was seasonal difference in prevalence for Amblyomma cajennense (Fabricius) sensu stricto (s.s), Amblyomma coelebs Neumann and larvae of Amblyomma. This difference was also found in the mean intensity of infestation of Amblyomma larvae and the mite Tur aragaoi (Fonseca). Only mean intensity of infestation differed in relation to host sex for the species Marmosa constantiae Thomas. Our results demonstrate that specificity between ectoparasites and small mammals in this region is moderately high and that the pattern of aggregation of some ectoparasite taxa differed between two seasons, as well as between sexes in M. constantiae.


Assuntos
Ectoparasitoses/veterinária , Mamíferos/parasitologia , Ácaros , Ftirápteros , Sifonápteros , Animais , Brasil , Feminino , Masculino , Estações do Ano , Fatores Sexuais
12.
J Helminthol ; 94: e141, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32238198

RESUMO

Larval stages of pentastomids were collected from different organs of small mammals from the Peruvian Amazon. These parasitized mammals included: a western Amazonian oryzomys (Hylaeamys perenensis), an elegant oryzomys (Euryoryzomys nitidus), a lowland paca (Cuniculus paca), two kinkajous (Potos flavus), two silvery woolly monkeys (Lagothrix poeppigii) and a brown-mantled tamarin (Leontocebus fuscicollis). Pentastomids were found in the mesentery and parenchyma of the liver and lungs of these animals. All pentastomids were morphologically identified as nymphs of Porocephalus spp. Only the nymphs collected from select animals (the western Amazonian oryzomys, the elegant oryzomys and the brown-mantled tamarin) were analysed molecularly. Molecular analysis was performed amplifying the mitochondrial cytochrome c oxidase subunit I gene from select nymphs collected from the western Amazonian oryzomys, the elegant oryzomys and the brown-mantled tamarin. The nucleotide sequences exhibited 95.8-97.7% similarity between them. Also, these sequences showed an identity of 95.8-97.9% to Porocephalus crotali (GenBank accession numbers MG559647-MG559655). Molecular analysis indicated the presence of at least two Porocephalus species. These findings represent the first record of Porocephalus in these mammals, thus adding new intermediate hosts for this pentastomid genus. This work represents the first molecular data of Porocephalus in a Neotropical climate.


Assuntos
Mamíferos/parasitologia , Doenças Parasitárias em Animais/parasitologia , Pentastomídeos/anatomia & histologia , Vísceras/parasitologia , Animais , Feminino , Estágios do Ciclo de Vida , Fígado/parasitologia , Pulmão/parasitologia , Masculino , Ninfa/genética , Pentastomídeos/classificação , Peru , Clima Tropical
13.
Parasit Vectors ; 13(1): 79, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066493

RESUMO

BACKGROUND: Culicoides biting midges are potential vectors of different pathogens. However, especially for eastern Europe, there is a lack of knowledge on the host-feeding patterns of this vector group. Therefore, this study aimed to identify Culicoides spp. and their vertebrate hosts collected in a wetland ecosystem. METHODS: Culicoides spp. were collected weekly from May to August 2017, using Biogents traps with UV light at four sites in the Danube Delta Biosphere Reserve, Romania. Vectors and hosts were identified with a DNA barcoding approach. The mitochondrial cytochrome c oxidase subunit 1 was used to identify Culicoides spp., while vertebrate hosts were determined targeting cytochrome b or 16S rRNA gene fragments. A maximum likelihood phylogenetic tree was constructed to verify the biting midge identity against other conspecific Palaearctic Culicoides species. A set of unfed midges was used for morphological confirmation of species identification using slide-mounted wings. RESULTS: Barcoding allowed the species identification and detection of corresponding hosts for 1040 (82.3%) of the 1264 analysed specimens. Eight Culicoides spp. were identified with Culicoides griseidorsum, Culicoides puncticollis and Culicoides submaritimus as new species records for Romania. For 39 specimens no similar sequences were found in GenBank. This group of unknown Culicoides showed a divergence of 15.6-16.3% from the closest identified species and clustered in a monophyletic clade, i.e. a novel species or a species without reference sequences in molecular libraries. For all Culicoides spp., nine mammalian and 24 avian species were detected as hosts. With the exception of C. riethi (n = 12), at least one avian host was detected for all Culicoides spp., but this host group only dominated for Culicoides kibunensis and the unknown Culicoides sp.. The most common host group were mammals (n = 993, 87.6% of all identified blood sources) dominated by cattle (n = 817, 70.6%). CONCLUSIONS: Most Culicoides spp. showed a broad host-feeding pattern making them potential bridge vectors. At the same time, new records of biting midge species for Romania, as well as a potentially unknown Culicoides species, highlight the lack of knowledge regarding the biting midge species and their genetic diversity in eastern Europe.


Assuntos
Sangue , Ceratopogonidae/classificação , Ceratopogonidae/fisiologia , Especificidade de Hospedeiro , Filogenia , Animais , Código de Barras de DNA Taxonômico , Complexo IV da Cadeia de Transporte de Elétrons/genética , Comportamento Alimentar , Insetos Vetores/classificação , Mamíferos/parasitologia , RNA Ribossômico 16S/genética , Romênia , Áreas Alagadas
14.
Parasit Vectors ; 13(1): 74, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054541

RESUMO

BACKGROUND: The Dicrocoeliidae are digenetic trematodes mostly parasitic in the bile ducts and gall bladder of various avian and mammalian hosts. Until recently their systematics was based on morphological data only. Due to the high morphological uniformity across multiple dicrocoeliid taxa and insufficient knowledge of relative systematic value of traditionally used morphological characters, their taxonomy has always been unstable. Therefore, DNA sequence data provide a critical independent source of characters for phylogenetic inference and improvement of the system. METHODS: We examined the phylogenetic affinities of three avian dicrocoeliids representing the genera Brachylecithum, Brachydistomum and Lyperosomum, using partial sequences of the nuclear large ribosomal subunit (28S) RNA gene. We also sequenced the complete or nearly complete mitogenomes of these three isolates and conducted a comparative mitogenomic analysis with the previously available mitogenomes from three mammalian dicrocoeliids (from 2 different genera) and examined the phylogenetic position of the family Dicrocoeliidae within the order Plagiorchiida based on concatenated nucleotide sequences of all mitochondrial genes (except trnG and trnE). RESULTS: Combined nucleotide diversity, Kimura-2-parameter distance, non-synonymous/synonymous substitutions ratio and average sequence identity analyses consistently demonstrated that cox1, cytb, nad1 and two rRNAs were the most conserved and atp6, nad5, nad3 and nad2 were the most variable genes across dicrocoeliid mitogenomes. Phylogenetic analyses based on mtDNA sequences did not support the close relatedness of the Paragonimidae and Dicrocoeliidae and suggested non-monophyly of the Gorgoderoidea as currently recognized. CONCLUSIONS: Our results show that fast-evolving mitochondrial genes atp6, nad5 and nad3 would be better markers than slow-evolving genes cox1 and nad1 for species discrimination and population level studies in the Dicrocoeliidae. Furthermore, the Dicrocoeliidae being outside of the clade containing other xiphidiatan trematodes suggests a need for the re-evaluation of the taxonomic content of the Xiphidiata.


Assuntos
Aves/parasitologia , Dicrocoeliidae/classificação , Genoma Mitocondrial , Mamíferos/parasitologia , Filogenia , Animais , DNA Ribossômico/genética , Genes Mitocondriais , RNA Ribossômico 28S/genética , Análise de Sequência de DNA
15.
Sci Rep ; 10(1): 1853, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024939

RESUMO

Studies of host-parasite relationships largely benefit from adopting a multifactorial approach, including the complexity of multi-host systems and habitat features in their analyses. Some host species concentrate most infection and contribute disproportionately to parasite and vector population maintenance, and habitat feature variation creates important heterogeneity in host composition, influencing infection risk and the fate of disease dynamics. Here, we examine how the availability of specific groups of hosts and habitat features relate to vector abundance and infection risk in 18 vector populations along the Mediterranean-type ecosystem of South America, where the kissing bug Mepraia spinolai is the main wild vector of the parasite Trypanosoma cruzi, the etiological agent of Chagas disease. For each population, data on vectors, vertebrate host availability, vegetation, precipitation, and temperature were collected and analyzed. Vector abundance was positively related to temperature, total vegetation, and European rabbit availability. Infection risk was positively related to temperature, bromeliad cover, and reptile availability; and negatively to the total domestic mammal availability. The invasive rabbit is suggested as a key species involved in the vector population maintenance. Interestingly, lizard species -a group completely neglected as a potential reservoir-, temperature, and bromeliads were relevant factors accounting for infection risk variation across populations.


Assuntos
Doença de Chagas/etiologia , Doença de Chagas/parasitologia , Lagartos/parasitologia , Animais , Ecossistema , Interações Hospedeiro-Parasita/fisiologia , Insetos Vetores/parasitologia , Mamíferos/parasitologia , Coelhos , Risco , América do Sul , Temperatura , Triatominae/parasitologia , Trypanosoma cruzi/patogenicidade
16.
Syst Parasitol ; 97(1): 107-118, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31912418

RESUMO

Macropsylla Rothschild, 1905 is an endemic Australian flea genus represented by two species: M. hercules Rothschild, 1905 and M. novaehollandiae Hastriter, 2002. However, their identification is challenging. To address this difficulty, an extensive differential diagnosis for the two species is provided along with a key to distinguish Macropsylla from other Australian flea genera. The first record of M. hercules from the domestic cat (Felis catus (L.)) is also presented. The taxonomy, distribution, host relationships, evolution, and ecology of the Macropsylla species are discussed, along with the conservation biology of the threatened New Holland flea M. novaehollandiae.


Assuntos
Aves/parasitologia , Mamíferos/parasitologia , Sifonápteros/classificação , Sifonápteros/fisiologia , Animais , Austrália , Conservação dos Recursos Naturais , Especificidade de Hospedeiro , Filogenia , Especificidade da Espécie
17.
Trends Parasitol ; 36(1): 64-79, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31843535

RESUMO

Grazing mammals, ungulates, pose two evolutionary puzzles as helminth hosts. First, why do some helminths infect intermediate hosts prior to infecting ungulates, given that grazers could directly consume propagules on vegetation? Second, ungulates are large and long-lived, so why are they occasionally intermediate instead of definitive hosts, as in taeniid cestodes? We comprehensively surveyed helminth life cycles and transmission involving ungulates. We identified six transmission routes and found that ungulate helminth parasitism has evolved some 25 times. Direct egg transmission to ungulates is rare, and we suggest this is due to a transmission barrier caused by ungulate faecal avoidance. Our survey confirmed that ungulates are almost always definitive hosts, and we discuss the exceptional cases when they are not.


Assuntos
Evolução Biológica , Helmintíase Animal/parasitologia , Helmintíase Animal/transmissão , Helmintos/fisiologia , Estágios do Ciclo de Vida/fisiologia , Animais , Herbivoria , Mamíferos/parasitologia
18.
J Parasitol ; 106(6): 843-853, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33429437

RESUMO

Leech-derived invertebrate DNA (iDNA) has been successfully leveraged to conduct surveys of vertebrate host biodiversity across the Indo Pacific. However, this technique has been limited methodologically, typically only targeting mammalian 16S rDNA, or both 16S and vertebrate 12S rDNA for leech host determination. To improve the taxonomic richness of vertebrate host species in iDNA surveys, we re-analyze datasets from Bangladesh, Cambodia, China, and Madagascar through metabarcoding via next generation sequencing (NGS) of 12S, 16S (2 types, one designed to target mammals and the other, residual eDNA), nicotinamide adenine dinucleotide hydride dehydrogenase 2 (ND2), and cytochrome c oxidase subunit 1 (COI). With our 5 primer sets, we identify 41 unique vertebrate hosts to the species level, among 1,200 leeches analyzed, along with an additional 13 taxa to the family rank. Within our 41 taxa, we note that adding ND2 and COI loci increased species richness detection by 25%. NGS has emerged as more efficient than Sanger sequencing for large scale metabarcoding applications and, with the decline in cost of NGS, our pooled sample multilocus protocol is an attractive option for iDNA biodiversity surveys.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Sanguessugas/classificação , Tipagem de Sequências Multilocus/métodos , Vertebrados/classificação , Vertebrados/parasitologia , Anfíbios/sangue , Anfíbios/classificação , Anfíbios/genética , Anfíbios/parasitologia , Animais , Bangladesh , Biodiversidade , Aves/sangue , Aves/classificação , Aves/genética , Aves/parasitologia , Camboja , China , DNA/sangue , Sanguessugas/genética , Madagáscar , Mamíferos/sangue , Mamíferos/classificação , Mamíferos/genética , Mamíferos/parasitologia , Vertebrados/sangue , Vertebrados/genética
19.
Parasit Vectors ; 12(1): 567, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783770

RESUMO

BACKGROUND: A question of epidemiological relevance in Chagas disease studies is to understand Trypanosoma cruzi transmission cycles and trace the origins of (re)emerging cases in areas under vector or disease surveillance. Conventional parasitological methods lack sensitivity whereas molecular approaches can fill in this gap, provided that an adequate sample can be collected and processed and a nucleic acid amplification method can be developed and standardized. We developed a duplex qPCR assay for accurate detection and quantification of T. cruzi satellite DNA (satDNA) sequence in samples from domestic and sylvatic mammalian reservoirs. The method incorporates amplification of the gene encoding for the interphotoreceptor retinoid-binding protein (IRBP), highly conserved among mammalian species, as endogenous internal amplification control (eIAC), allowing distinction of false negative PCR findings due to inadequate sample conditions, DNA degradation and/or PCR interfering substances. RESULTS: The novel TaqMan probe and corresponding primers employed in this study improved the analytical sensitivity of the assay to 0.01 par.eq/ml, greater than that attained by previous assays for Tc I and Tc IV strains. The assay was tested in 152 specimens, 35 from 15 different wild reservoir species and 117 from 7 domestic reservoir species, captured in endemic regions of Argentina, Colombia and Mexico and thus potentially infected with different parasite discrete typing units. The eIACs amplified in all samples from domestic reservoirs from Argentina and Mexico, such as Canis familiaris, Felis catus, Sus scrofa, Ovis aries, Equus caballus, Bos taurus and Capra hircus with quantification cycles (Cq's) between 23 and 25. Additionally, the eIACs amplified from samples obtained from wild mammals, such as small rodents Akodon toba, Galea leucoblephara, Rattus rattus, the opossums Didelphis virginiana, D. marsupialis and Marmosa murina, the bats Tadarida brasiliensis, Promops nasutus and Desmodus rotundus, as well as in Conepatus chinga, Lagostomus maximus, Leopardus geoffroyi, Lepus europaeus, Mazama gouazoubira and Lycalopex gymnocercus, rendering Cq's between 24 and 33. CONCLUSIONS: This duplex qPCR assay provides an accurate laboratory tool for screening and quantification of T. cruzi infection in a vast repertoire of domestic and wild mammalian reservoir species, contributing to improve molecular epidemiology studies of T. cruzi transmission cycles.


Assuntos
Doença de Chagas/veterinária , Reservatórios de Doenças/parasitologia , Mamíferos/parasitologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , Doença de Chagas/diagnóstico , Primers do DNA/genética , Sondas de DNA/genética , DNA de Protozoário/isolamento & purificação , DNA Satélite/isolamento & purificação , Proteínas do Olho/genética , Proteínas de Ligação ao Retinol/genética , Sensibilidade e Especificidade , Trypanosoma cruzi
20.
BMC Genomics ; 20(1): 729, 2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31606027

RESUMO

BACKGROUND: The tropical liver fluke, Fasciola gigantica causes fasciolosis, an important disease of humans and livestock. We characterized dynamic transcriptional changes associated with the development of the parasite in its two hosts, the snail intermediate host and the mammalian definitive host. RESULTS: Differential gene transcription analysis revealed 7445 unigenes transcribed by all F. gigantica lifecycle stages, while the majority (n = 50,977) exhibited stage-specific expression. Miracidia that hatch from eggs are highly transcriptionally active, expressing a myriad of genes involved in pheromone activity and metallopeptidase activity, consistent with snail host finding and invasion. Clonal expansion of rediae within the snail correlates with increased expression of genes associated with transcription, translation and repair. All intra-snail stages (miracidia, rediae and cercariae) require abundant cathepsin L peptidases for migration and feeding and, as indicated by their annotation, express genes putatively involved in the manipulation of snail innate immune responses. Cercariae emerge from the snail, settle on vegetation and become encysted metacercariae that are infectious to mammals; these remain metabolically active, transcribing genes involved in regulation of metabolism, synthesis of nucleotides, pH and endopeptidase activity to assure their longevity and survival on pasture. Dramatic growth and development following infection of the mammalian host are associated with high gene transcription of cell motility pathways, and transport and catabolism pathways. The intra-mammalian stages temporally regulate key families of genes including the cathepsin L and B proteases and their trans-activating peptidases, the legumains, during intense feeding and migration through the intestine, liver and bile ducts. While 70% of the F. gigantica transcripts share homology with genes expressed by the temperate liver fluke Fasciola hepatica, gene expression profiles of the most abundantly expressed transcripts within the comparable lifecycle stages implies significant species-specific gene regulation. CONCLUSIONS: Transcriptional profiling of the F. gigantica lifecycle identified key metabolic, growth and developmental processes the parasite undergoes as it encounters vastly different environments within two very different hosts. Comparative analysis with F. hepatica provides insight into the similarities and differences of these parasites that diverged > 20 million years ago, crucial for the future development of novel control strategies against both species.


Assuntos
Fasciola/crescimento & desenvolvimento , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Mamíferos/parasitologia , Caramujos/parasitologia , Animais , Evolução Molecular , Fasciola/genética , Regulação da Expressão Gênica , Especificidade de Hospedeiro , Humanos , Estágios do Ciclo de Vida , Família Multigênica , Proteínas de Protozoários/genética
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