Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 89
Filtrar
1.
Ticks Tick Borne Dis ; 15(3): 102331, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461653

RESUMO

In this study, we report soft ticks from bat-inhabiting caves in different areas of Brazil. From 2010 to 2019, we collected 807 tick specimens from nine caves located in four Brazilian states among two biomes. Ticks were morphologically identified as Antricola guglielmonei (282 specimens), Ornithodoros cavernicolous (260 specimens), and Ornithodoros fonsecai (265 specimens). Whereas A. guglielmonei was collected on bat guano in hot caves, O. cavernicolous and O. fonsecai were collected in cracks and crevices on the walls of cold caves, sometimes in the same chamber. Morphological identifications were corroborated by molecular and phylogenetic analyses inferred from tick mitochondrial 16S rRNA gene partial sequences. The sequences of A. guglielmonei, O. cavernicolous and O. fonsecai collected in this study clustered with conspecific GenBank sequences from different localities of Brazil. Remarkably, a clade containing 12 sequences of O. fonsecai was clearly bifurcated, denoting a degree of genetic divergence (up to 5 %) of specimens from Cerrado/Atlantic Forest biomes with the specimens from the Caatinga biome. To further evaluate this divergence, we performed morphometric analysis of the larval stage of different O. fonsencai populations by principal component analysis, which indicated that the larvae from Caatinga populations were generally smaller than the larvae from other biomes. Some of the present A. guglielmonei specimens were collected from the type locality of Antricola inexpectata. Comparisons of these specimens with the type specimens of A. inexpectata and A. guglielmonei indicated that they could not be separated by their external morphology. Hence, we are relegating A. inexpectata to a synonym of A. guglielmonei. This proposal is corroborated by our phylogenetic analysis.


Assuntos
Ácaros e Carrapatos , Argasidae , Quirópteros , Ornithodoros , Animais , Argasidae/genética , Brasil , RNA Ribossômico 16S/genética , Ácaros e Carrapatos/genética , Filogenia , Larva/genética
2.
Exp Appl Acarol ; 92(2): 241-252, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38321309

RESUMO

Tick-borne relapsing fever spirochetes of genus Borrelia thrive in enzootic cycles involving Ornithodoros spp. (Argasidae) mainly, and rodents. The isolation of these spirochetes usually involves a murine model in which ticks are fed and the spirochetes detected in blood several days later. Such an experiment also demonstrates that a given species of tick is competent in the transmission of the bacteria. Here, soft ticks Ornithodoros octodontus were collected in Northern Chile with the objective to experimentally determine its capacity to transmit a Borrelia sp. detected in a previous study. Two Guinea pigs (Cavia porcellus) were used to feed nymphs and adults of O. octodontus and the spirochetes in blood were inspected by dark-field microscopy and nested PCR. Although spirochetes were not seen in blood, DNA was detected in only one animal 11 days after the ticks were fed. Genetic sequences of Borrelia flaB, clpX, pepX, recG, rplB, and uvrA genes retrieved from DNA extraction of positive blood were employed to construct two phylogenetic analyses. On the one hand, the flaB tree showed the Borrelia sp. transmitted by O. octodontus clustering with Borrelia sp. Alcohuaz, which was previously detected in that same tick species. On the other hand, concatenated clpX-pepX-recG-rplB-uvrA demonstrated that the characterized spirochete branches together with "Candidatus Borrelia caatinga", a recently discovered species from Brazil. Based on the genetic profile presented in this study, the name "Candidatus Borrelia octodonta" is proposed for the species transmitted by O. octodontus. The fact that spirochetes were not observed in blood of guinea pigs, may reflect the occurrence of low spirochetemia, which could be explained because the susceptibility of infection varies depending on the rodent species that is used in experimental models. Although the vertebrate reservoir of "Ca. Borrelia octodonta" is still unknown, Octodon degus, a rodent species that is commonly parasitized by O. octodontus, should be a future target to elucidate this issue.


Assuntos
Argasidae , Borrelia , Besouros , Ornithodoros , Febre Recorrente , Doenças dos Roedores , Animais , Cobaias , Camundongos , Ornithodoros/genética , Febre Recorrente/veterinária , Febre Recorrente/epidemiologia , Febre Recorrente/microbiologia , Chile , Filogenia , Roedores , DNA
3.
Ticks Tick Borne Dis ; 15(2): 102294, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38086247

RESUMO

This work aimed to report ticks infesting the wildlife among 15 municipalities of the state of Espírito Santo between 2016 and 2021, within the Atlantic Forest biome of southeastern Brazil. A total of 576 tick specimens (187 males, 56 females, 149 nymphs, and 184 larvae) was collected from 41 species of wild vertebrates (two reptiles, nine mammals, and 30 birds). Ticks were identified by morphological or molecular methods into 18 species, being 12, four, one and one of the genera Amblyomma, Ixodes, Rhipicephalus and Ornithodoros, respectively. Amblyomma rotundatum was the only species collected from reptiles. Ticks collected from mammals were identified as Amblyomma brasiliense, Amblyomma calcaratum, Amblyomma dubitatum, Amblyomma longirostre, Amblyomma nodosum, Amblyomma pacae, Amblyomma sculptum, Amblyomma varium and Rhipicephalus microplus. Amblyomma sculptum was the species found on the widest variety of hosts, collected from four mammal orders and five bird orders. Passeriformes birds were infested by Amblyomma fuscum, A. longirostre (also found on non- passerine birds), A. nodosum, Amblyomma parkeri, Amblyomma romarioi, A. varium and Ixodes loricatus. An adult female of Ixodes rio was collected from a Piciformes bird. Seabirds of the order Procellariiformes were infested by Ixodes percavatus sensu lato and Ixodes uriae. The argasid Ornithodoros capensis was collected from an offshore metallic platform that was used by Suliformes seabirds. Rickettsial agents of the spotted fever group, Rickettsia amblyommatis and Rickettsia sp. strain Pampulha, were detected in the ticks A. longirostre [from the Paraguayan hairy dwarf porcupine (Coendou spinosus)] and A. dubitatum [from the capybara (Hydrochoerus hydrochaeris)], respectively. The following nine tick species are reported for the first time in Espírito Santo state: A. calcaratum, A. fuscum, A. pacae, A. parkeri, A. romarioi, I. loricatus, I. rio, I. uriae, and O. capensis. Although it is also the first report of I. uriae in Brazil, we do not consider it established in the country. Multiple new tick-host associations are reported in the present study.


Assuntos
Ixodes , Ixodidae , Ornithodoros , Rhipicephalus , Infecções por Rickettsia , Rickettsia , Doenças dos Roedores , Infestações por Carrapato , Masculino , Animais , Feminino , Animais Selvagens , Brasil/epidemiologia , Ixodidae/microbiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Infecções por Rickettsia/microbiologia , Mamíferos , Amblyomma , Roedores
4.
Ticks Tick Borne Dis ; 15(2): 102303, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38113807

RESUMO

Ticks are obligate hematophagous parasites that can transmit to vertebrate hosts several pathogens, including viruses, bacteria, protozoa and helminths. Among these agents, some Borrelia species some Borrelia species cause disease in humans and other vertebrate hosts; therefore, they have medical and veterinary health importance. To gather additional information on Borrelia species in Brazil, the current study aimed to detect the presence of these species in Ornithodoros cavernicolous ticks collected in September 2019 from cement pipes that are used by bats as shelter in a farm located in the midwestern region of Brazil. DNA samples obtained from 18 specimens of O. cavernicolous were subjected of two polymerase chain reactions, targeting a segment of the Borrelia fla B gene. Of the samples tested, only one (6 %, 1/18) showed amplification. The nucleotide sequence of the amplified DNA showed more than 97 % (293/300) identity with a sequence of a Borrelia sp. detected in blood collected from a bat from Macaregua Cave, Colombia, and more than 97 % (292/300) detected in lungs from vampire bats from northeastern Brazil. The deduced amino acid sequences were identical to each other. Phylogenetic analysis indicated that these sequences formed a group of Borrelia species (putatively associated with bats) that is closely related to sequences of Borrelia species of the Lyme borreliosis group. Further investigations should be carried out in order to determine whether the sequence of the Borrelia sp. we found belongs to a new taxon. It will also be of great importance to determine which vertebrate hosts, besides bats, O. cavernicolous ticks can parasitize in order to investigate whether the Borrelia sp. we found may be transmitted and cause disease to the other vertebrate hosts.


Assuntos
Ácaros e Carrapatos , Argasidae , Borrelia , Quirópteros , Ornithodoros , Humanos , Animais , Ornithodoros/microbiologia , Argasidae/genética , Borrelia/genética , Ácaros e Carrapatos/genética , Brasil/epidemiologia , Quirópteros/parasitologia , Filogenia , DNA
5.
Rev Bras Parasitol Vet ; 33(1): e014523, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126574

RESUMO

A male of Pteronura brasiliensis (Carnivora: Mustelidae) was found dead on the banks of the Rio Negro, in the Pantanal wetlands of Mato Grosso do Sul state, Aquidauana municipality. Two ticks found attached to its skin were morphologically identified as a second-instar nymph of Ornithodoros rostratus (Argasidae) and a male of Amblyomma sculptum (Ixodidae). In order to complement the morphological identification, these tick specimens were subjected to DNA extraction, and tested using PCR assays to confirm the molecular identity the specimens. Also, the tick DNA samples were tested and were negative in the PCR assays for all the pathogens tested. We also examined 30 batches, consisting of 174 individuals of O. rostratus deposited in the Acari Collection of the Butantan Institute, and we found material from four Brazilian states, including one batch containing 2 males and 2 females from Aquidauana, of Mato Grosso do Sul state, collected from the soil. This was therefore the first record of O. rostratus parasitizing P. brasiliensis and the first locality record (Aquidauana). Likewise, A. sculptum is commonly found in the Pantanal and is reported here for the second time parasitizing the giant otter, which is a host little studied regarding the ectoparasites.


Assuntos
Ixodidae , Ornithodoros , Lontras , Humanos , Feminino , Animais , Masculino , Amblyomma , Brasil , DNA
6.
Exp Appl Acarol ; 91(1): 99-110, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37584844

RESUMO

Soft ticks from the Ornithodoros genus are vectors of relapsing fever (RF) spirochetes around the world. In Mexico, they were originally described in the 19th century. However, few recent surveillance studies have been conducted in Mexico, and regions where RF spirochetes circulate remain vague. Here, the presence of soft ticks in populated areas was assessed in two sites from the Mexican states of Aguascalientes and Zacatecas. Argasidae ticks were collected, identified by morphology and mitochondrial 16S rDNA gene sequencing, and tested for RF borreliae. The specimens in both sites were identified as Ornithodoros turicata but no RF spirochetes were detected. These findings emphasize the need to update the distribution of these ticks in multiple regions of Mexico and to determine the circulation of RF borreliosis in humans and domestic animals.


Assuntos
Argasidae , Borrelia , Ornithodoros , Febre Recorrente , Humanos , Animais , Febre Recorrente/epidemiologia , Borrelia/genética , Animais Domésticos
7.
Parasitol Res ; 122(10): 2335-2352, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37597061

RESUMO

Bats harbor diverse groups of ectoparasites, such as insects and mites like ticks (Ixodida). Some species of ticks with records for bats and humans have already been reported with the occurrence of pathogens. This research article aims to document new geographical and host records of ticks infesting bats in Rio de Janeiro state, Southeastern Brazil, and provides a list of tick species associated with bats in Brazil. We counted 12 argasid ticks and five ixodid ticks associated with six individuals of bats. Larvae of Amblyomma sp., Ixodes sp., Ornithodoros sp., and Ornithodoros hasei and one nymph of Amblyomma sculptum parasitizing Artibeus obscurus, Phyllostomus hastatus, Micronycteris sp., Molossus fluminensis, and Carollia perspicillata in different localities of Rio de Janeiro state were studied. We carried out a systematic review with the descriptors: tick bat Brazil. We considered data from 42 articles in the systematic review. We compiled eleven records of Ixodidae, and 160 records of Argasidae. Ornithodoros cavernicolous were the most recorded tick species. Overall, we registered 171 tick-bat or roost-bat associations with 85 records of these infesting bats. The review also shows the occurrence of tick species associated with bats, and we present new records on ticks parasitizing bats in Brazil.


Assuntos
Argasidae , Quirópteros , Ixodidae , Ornithodoros , Humanos , Animais , Brasil/epidemiologia , Amblyomma
8.
J Med Entomol ; 60(5): 968-977, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37455018

RESUMO

Soft ticks (Argasidae) of the Pavlovskyella Pospelova-Shtrom subgenus are important vectors of relapsing fever spirochetes, which are agents of disease globally. South American representatives of the Pavlovskyella subgenus include 3 species: Ornithodoros (Pavlovskyella) brasiliensis Aragão, Ornithodoros (Pavlovskyella) furcosus Neumann, and Ornithodoros (Pavlovskyella) rostratus Aragão. Here, we describe a fourth species based on morphological and mitogenomic evidence of ticks collected in burrows of unknown hosts in central Chile. The larva of the new species separates from other South American soft ticks by the following combination of characters: 13 pairs of dorsolateral setae, dorsal plate hexagonal, hypostome blunt with denticles from apex almost to the base. Adults of this new species lack cheeks, possess a dorsoventral groove, and have humps, similar to O. (P.) brasiliensis; however, they lack bulging structures on the flanks of idiosoma. Moreover, females and males differ from O. (P.) rostratus by having 3 humps instead of spurs in tarsi I and from O. (P.) furcosus because of their smaller size and thinner anterior lip of the genital aperture in females. The phylogenetic analysis performed with mitogenomes of the Argasidae family depicts the new Pavlovskyella species from Chile in a monophyletic clade with other South American species in the subgenus, confirming a regional group.


Assuntos
Ácaros e Carrapatos , Argasidae , Ornithodoros , Feminino , Masculino , Animais , Argasidae/genética , Chile , Filogenia , Ornithodoros/genética
9.
Vet Res Commun ; 47(4): 2339-2350, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37422609

RESUMO

Bats represent the second order of mammals with the highest number of species worldwide with over 1,616 species, and almost 10% of them are recorded in Mexico. These mammals have a great diversity of ectoparasites, in particular soft ticks of the genus Ornithodoros. Desmodus rotundus is one of the bat species that has scarcely been studied in terms of tick species richness in Mexico, with three tick species reported in five of the 32 Mexican states. For this reason, the aim of the present work was to identify ticks associated with D. rotundus from Central Mexico. Fieldwork was undertaken in the municipality El Marqués, Ejido Atongo A, Querétaro, Mexico. Bats were captured using mist nets and were visually inspected for tick presence. The ectoparasites were identified morphologically and molecularly with the use of mitochondrial markers 16SrDNA and cytochrome oxidase subunit I (COI). A total of 30 D. rotundus (1 female, 29 males) were captured, from which 20 larvae identified as Ornithodoros yumatensis were recovered. Molecular analysis confirmed the presence of this species with identity values of 99-100% with sequences of this species from the southwestern US, and the Yucatán Peninsula, Mexico. This is the first report of ticks associated with bats for the state of Querétaro, providing the first sequences of the COI gene from Mexican populations of O. yumatensis and shows an increase in the distribution of this soft tick across Central Mexico.


Assuntos
Quirópteros , Ornithodoros , Masculino , Animais , Feminino , Ornithodoros/genética , México , Quirópteros/genética , Código de Barras de DNA Taxonômico/veterinária , Larva , Filogenia
10.
Parasitol Res ; 122(5): 1213-1219, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36897382

RESUMO

The in vitro feeding of ticks facilitates the conduction of studies involving the intrinsic vector-pathogen relationship, susceptibility tests, and resistance to acaricides, in addition to mimicking the use of experimental hosts. The objective of this study was to establish an in vitro feeding system using silicone membranes to supply various diets to the species Ornithodoros rostratus. Each experimental group included 130 first-instar O. rostratus nymphs. The groups were divided according to the diet provided: citrated rabbit blood, citrated bovine blood, bovine blood with antibiotics, and defibrinated bovine blood. The control group was fed directly on rabbits. Ticks were weighed before and after the feeding and monitored individually according to their biological parameters. The results of the experiment demonstrated that the proposed system was efficient in terms of fixation stimulus and satisfactory in terms of tick engorgement, which would allow the maintenance of O. rostratus colonies by using artificial feeding through silicone membranes. All diets provided were efficient for the maintenance of colonies, but the ticks that received citrated rabbit blood displayed similar biological parameters to those observed under in vivo feeding conditions.


Assuntos
Acaricidas , Ornithodoros , Animais , Bovinos , Coelhos , Silicones , Ninfa , Citratos , Ácido Cítrico , Apoio Nutricional , Comportamento Alimentar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA