RESUMO
The genus Bartonella comprises emerging bacteria that affect humans and other mammals worldwide. Felids represent an important reservoir for several Bartonella species. Domestic cats are the main reservoir of Bartonella henselae, the agent of cat scratch disease (CSD). It can be transmitted directly by scratches and bites from infected cats and via cat fleas. This study aims to investigate the circulation of Bartonella spp. in free-ranging Neotropical wild felids from Southern Brazil using serological and molecular methods. In this study, 53 live-trapped free-ranging wild felids were sampled, 39 Leopardus geoffroyi and 14 Leopardus wiedii, from five municipalities in the Rio Grande, do Sul state, southern Brazil. All captured animals were clinically healthy. Two blood samples of L. geoffroyi were positive, by PCR, for the presence of B. henselae DNA. Conversely, none of L. wiedii blood samples were positive when tested using PCR. Indirect immunofluorescence assay (IFA) showed that 28% of serum samples of wild felids were reactive (seropositive) for B. henselae by immunofluorescence, with titers ranging from 64 to 256. The results presented here provide the first evidence of a Bartonella-enzootic cycle involving L. geoffroyi and L. wiedii, which may account for the spillover of the emerging zoonotic pathogen B. henselae for the indigenous fauna in Southern Brazil.
Assuntos
Bartonella henselae/isolamento & purificação , Doença da Arranhadura de Gato/veterinária , Felidae/microbiologia , Animais , Animais Selvagens , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/genética , Bartonella/classificação , Bartonella/genética , Bartonella/imunologia , Bartonella/isolamento & purificação , Bartonella henselae/classificação , Bartonella henselae/genética , Bartonella henselae/imunologia , Brasil , Doença da Arranhadura de Gato/microbiologia , DNA Bacteriano/genética , Pradaria , Nucleotidiltransferases/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , FilogeniaRESUMO
Chigger mites are ectoparasites of terrestrial tetrapods and can cause dermatitis in the host, known as trombiculiasis. In Brazil, there are 73 species of chiggers; however, cats never have recorded as a host in this country. Here, we report the first record of chiggers parasitizing a domestic cat in Brazil; and a new locality for Eutrombicula tinami (Oudemans 1910) in the Rio Grande do Sul state, Brazil.
Assuntos
Doenças do Gato/parasitologia , Dermatite/veterinária , Larva/classificação , Trombiculíase/veterinária , Trombiculidae/classificação , Animais , Brasil , Gatos , Infestações por Ácaros/veterinária , Trombiculidae/genéticaRESUMO
Bats and dogs are the main reservoirs of rabies virus (RABV) in Latin America and are responsible for the maintenance of different cycles of infection. In the two neighbour and most southern Brazilian states of Rio Grande do Sul (RS) and Santa Catarina (SC), rabies in dogs has been successfully controlled for more than 30 years. However, rabies associated to the rural cycle remains endemic, with a significant, though oscillating-annual incidence of rabies in cattle. Despite the plethora of studies on genetic analyses of Brazilian RABV, isolates from southern Brazil have only scarcely been investigated. This work was performed to identify the genetic lineages of RABVs circulating in states of RS and SC. Fifty-nine RABV cattle isolates from RS and SC were selected and submitted to reverse transcription/polymerase chain reaction (RT-PCR) followed by sequencing of the nucleoprotein gene. In RS, the circulation of two sublineages (1A and 1B) of RABV was detected, both with characteristics of lineages usually detected in vampire bats (Desmodus rotundus). In SC, only one sublineage of RABV (1B) was detected. Nevertheless, the findings reported here are expected to contribute to the understanding of the biology of the virus in the region and its interactions with the natural host D. rotundus.
Assuntos
Filogenia , RNA Viral/isolamento & purificação , Vírus da Raiva/isolamento & purificação , Raiva/virologia , Animais , Brasil , Bovinos , Quirópteros/virologia , Cães , RNA Viral/genética , Raiva/diagnóstico , Raiva/epidemiologia , Vírus da Raiva/patogenicidadeRESUMO
Fleas are insects with a worldwide distribution that have been implicated in the transmission of several pathogens. The present study aimed to investigate the presence of Rickettsia spp. (Rickettsiales: Rickettsiaceae) and Bartonella spp. (Rhizobiales: Bartonellaceae) in fleas from free-ranging crab-eating foxes Cerdocyon thous (Linnaeus, 1766) (Carnivora: Canidae) from Rio Grande do Sul, southern Brazil. Fleas were collected manually from animals and used for the molecular detection of Rickettsia spp. and Bartonella spp. Twenty-nine C. thous were sampled in six municipalities. Four foxes were parasitized by 10 fleas, all of which were identified as Ctenocephalides felis (Bouché, 1935) (Siphonaptera: Pulicidae). DNA from Rickettsia felis Bouyer et al., 2001 and Rickettsia asembonensis Maina et al., 2016 were found in three and eight fleas, respectively. In four fleas, DNA of Bartonella sp. was identified. Phylogenetic analysis grouped Bartonella sp. together with other genotypes previously reported in C. felis worldwide. The scenario described in the present study highlights a Neotropical canid parasitized by the invasive cosmopolitan cat flea, which in turn, is carrying potentially invasive vector-borne microorganisms. These findings suggest that C. felis is adapted to wild hosts in wilderness areas in southern Brazil, hypothetically exposing the Neotropical fauna to unknown ecological and health disturbances.
Assuntos
Bartonella/isolamento & purificação , Canidae/parasitologia , Ctenocephalides/microbiologia , Infestações por Pulgas/veterinária , Rickettsia/isolamento & purificação , Animais , Brasil/epidemiologia , Infestações por Pulgas/epidemiologia , Infestações por Pulgas/parasitologia , Insetos Vetores/microbiologia , PrevalênciaRESUMO
Spotted fever (SF) is a tick-borne disease associated with Rickettsia spp.. In the Pampa biome, Southern Brazil, cases of SF seem to be strongly linked with the practice of hunting wild animals. An investigation of rickettsiae in tick species found on wild animals could provide more information regarding the rickettsiosis enzootic cycle. The aim of this study is to describe the results of a molecular survey of Rickettsia spp. in the Neotropical deer tick, Haemaphysalis juxtakochi Cooley, 1946 (Acari: Ixodidae), from the Brazilian Pampa. Ticks were obtained from 14 road-killed gray brocket deer, Mazama gouazoubira (Artiodactyla: Cervidae), found in nine different municipalities of Rio Grande do Sul state, Southern Brazil. Ticks were processed individually to obtain genomic DNA, and then Rickettsia spp. was investigated using a set of PCR reactions that amplified the rickettsial fragments of the gltA, ompA, and htrA genes. Of the 24 tick samples tested, DNA of Rickettsia parkeri sensu stricto (s.s.) was found in 11 H. juxtakochi specimens collected in two different areas of the Brazilian Pampa. This is the first report of R. parkeri s.s. (the main agent associated with SF in the Uruguayan, Argentinian, and Brazilian Pampa) in H. juxtakochi ticks. These findings indicate that R. parkeri s.s. may be much more common and widely distributed in the Pampa biome than previously assumed. Moreover, H. juxtakochi ticks and gray brocket deer could participate in the potential spillover of R. parkeri s.s. from endemic to non-endemic areas in the South American Pampa.
Assuntos
Cervos/parasitologia , Ixodes/microbiologia , Rickettsia/isolamento & purificação , Animais , Animais Selvagens/parasitologia , Brasil/epidemiologia , Reservatórios de Doenças/microbiologia , Ixodes/genética , Reação em Cadeia da Polimerase , Rickettsia/classificação , Rickettsia/genética , Rickettsia/fisiologia , Inquéritos e QuestionáriosRESUMO
Sporothrix brasiliensis has emerged as an important cause of sporotrichosis, particularly associated with feline and zoonotic cases. Owing to the paucity of data on antifungal activity against this species, the present study aimed to evaluate the in vitro susceptibility of clinical isolates of S. brasiliensis in the mycelial and yeast phases to itraconazole (ITZ), terbinafine (TRB), and amphotericin B (AMB). Thirty-five isolates from an outbreak of feline sporotrichosis in Southern Brazil were used. All of them were assessed in the yeast and filamentous phases using the broth microdilution technique in accordance with the respective reference protocols M27-A3 and M38-A2 of the Clinical and Laboratory Standards Institute (CLSI). In our study, TRB was the most active antifungal against both the filamentous and yeast phases, showing GM of the MIC of 0.343 µg/ml and 0.127 µg/ml, respectively. In the yeast phase, the GM of the MIC for TRB was significantly lower than that for both ITZ (P = .009) and AMB (P < .001). However, in the filamentous phase, the GM of the MIC for TRB was significantly lower than that of AMB (P < .001), but not different from that of ITZ (P = .091). AMB was the antifungal with the highest GM of the MIC for both phases (1.486 µg/ml for the filamentous phase and 0.660 µg/ml for the yeast). Our results may contribute to a better understanding of antifungal susceptibility profiles of clinical isolates of S. brasiliensis in the mycelial and yeast phases in further studies.
Assuntos
Antifúngicos/farmacologia , Doenças do Gato/microbiologia , Sporothrix/efeitos dos fármacos , Esporotricose/veterinária , Anfotericina B/farmacologia , Animais , Brasil , Gatos , Itraconazol/farmacologia , Estágios do Ciclo de Vida/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Micélio/efeitos dos fármacos , Naftalenos/farmacologia , Esporotricose/microbiologia , TerbinafinaRESUMO
Paracoccidioidomycosis (PCM) is a systemic mycosis that occurs in several Latin American countries, especially in Brazil. It is caused by the thermo-dimorphic fungus Paracoccidioides spp. Serological studies to detect animal infection represent an excellent strategy for data on the agent's ecology. Although the state of Rio Grande do Sul (RS) is an endemic area for PCM in humans, there is scarce information available on the ecology of the agent in the region. This study aimed to investigate the infection by Paracoccidioides lutzii in animals living in RS, Brazil. A total of 85 wild mammals, 200 horses and 196 domestic dogs, previously tested for infection by P. brasiliensis, were included in this study. Serum samples from the animals were tested by ELISA to detect anti- P. lutzii antibodies. From the 481 animals tested, 105 (21.8%) were seropositive for IgG anti-P. lutzii. Of these, 54 were also positive for P. brasiliensis. A total of 11 horses (10.5%), 30 dogs (28.8%) and 10 wild mammals (9.5%) were positive only for P. lutzii (n=51). The detection of anti-P. lutzii antibodies in animals of RS suggests that the fungus can be found in southern Brazil, despite being described mainly in the midwest and southeast of the country.
Assuntos
Mamíferos/microbiologia , Paracoccidioides/isolamento & purificação , Paracoccidioidomicose/veterinária , Animais , Anticorpos Antifúngicos/sangue , Antígenos de Fungos/imunologia , Brasil/epidemiologia , Cães/microbiologia , Ensaio de Imunoadsorção Enzimática , Cavalos/microbiologia , Humanos , Paracoccidioidomicose/epidemiologiaRESUMO
The natural areas of the Coastal Plain of Rio Grande do Sul (CPRS) have suffered fragmentation due to anthropic action. The faunal surveys offer a low-cost method to quickly evaluate environmental alterations, and Syrphidae flies are often used as models in this kind of study. We aimed to ascertain the diversity of Syrphidae in the South region of Brazil by estimating its species' richness, and to use this data to identify new areas for conservation. In this survey Malaise traps were installed for 8 days in the CPRS, which was divided into five regions. Each region was subdivided into seven collecting areas and each of those areas received four traps, totaling 140 traps. A total of 456 Syrphidae individuals from 18 genera and 49 species were collected. In Region 1, there were nine exclusive species; in Region 2, there were three; in Region 3, there were 13, ten of which came from Estação Ecológica do Taim (ESEC Taim). In the Individual-based rarefaction analysis, Region 1 possessed the largest number of expected species out of the regions in the CPRS; we found 97% of these species. This insect collection effort, as one of the first in the CPRS, has broadened the known geographic distributions of 11 species of Syrphidae, and also indicated areas to be conserved. Additionally, it gave support for expanding ESEC Taim and creating new areas of conservation in Region 1, in Arroio Pelotas and Arroio Corrientes.
Assuntos
Biodiversidade , Dípteros , Animais , BrasilRESUMO
Cattle are the main hosts of Rhipicephalus microplus; however, this ixodid can also parasitize other animal species. We collected a specimen of R. microplus larvae from one bat Molossus rufus (Mammalia, Chiroptera) from the Cachoeirinha municipality (29° 56' 52'' S and 51° 5' 43'' W), Rio Grande do Sul, Brazil. The specimen was taxonomically identified using identification keys (Vargas 2006). This study reports the first occurrence of this species parasitizing insectivorous bats in Brazil.
Assuntos
Quirópteros , Rhipicephalus , Bovinos , Animais , Larva , BrasilRESUMO
In 2020, adult hard ticks (males and females) were collected from great horned owls [Bubo virginianus (Gmelin, 1788)] in the coastal region in southern Brazil. The engorged females were allowed to oviposit in the laboratory and hatched larvae could be obtained. Analyses of the external morphology of the adult ticks revealed that they represent a new species, which was named Amblyomma monteiroae n. sp. Partial sequences of the mitochondrial 16S rRNA gene and the nuclear second internal transcribed spacer (ITS2) were generated from a male and a female. Their 16S rRNA haplotypes were identical to each other and closest (96% identity) to corresponding sequences of Amblyomma parvitarsum Neumann, 1901, and 90% identical to Amblyomma neumanni Ribaga, 1902. Their ITS2 haplotypes were 95.8 to 96.0 identical to the single ITS-2 partial sequence of A. parvitarsum available in GenBank. In the phylogenetic trees inferred by both 16S rRNA and ITS2 partial sequences, A. monteiroae n. sp. formed a clade with A. parvitarsum, with A. neumanni branching sister to this clade. Amblyomma monteiroae n. sp. is genetically and morphologically related to A. parvitarsum. Both tick species are unique in combining the following morphological characters: scutum extensively ornate; eyes rounded and bulging; coxa I with two moderate pointed spurs, the external longer than the internal; a single triangular short spur on coxae II-III; presence of two spines on the tibia of legs II-IV; hypostomal dentition 3/3, trochanters without spurs. However, the males of the two species can be separated by specific features in palps and festoons, whereas the females differ in specific features of the coxal spurs. The larva of A. monteiroae n. sp. can be morphologically distinguished from A. parvitarsum only by morphometry, with the former species being slightly smaller. Currently, A. monteiroae n. sp. is restricted to southern Brazil, and the only known host is B. virginianus (Strigiformes: Strigidae). The present study increases the Amblyomma Brazilian fauna to 34 species.
Assuntos
Ixodidae , Parasitos , Estrigiformes , Masculino , Feminino , Animais , Amblyomma/genética , Estrigiformes/genética , Parasitos/genética , Brasil , RNA Ribossômico 16S/genética , Filogenia , Ninfa , LarvaRESUMO
The cattle tick, Rhipicephalus microplus, causes severe economic losses to beef and dairy production in several countries. The control of the cattle tick is based mostly on chemical acaricides. Currently, there are reports of tick populations resistant to all six classes of acaricides available on the market. The aim of this work was to evaluate two protocols for the control of the cattle tick, R. microplus, under field conditions. For that, an acaricide rotational-based approach and selective (partial)-based protocols were tested against a multi-resistant tick strain. Eighteen Brangus cattle were divided into three experimental groups: Group 1, a rotational-based approach aiming at six treatments per year (spring-spring period) using four different classes of acaricide (IPV6 protocol); Group 2, a selective (partial) and rotational-based protocol, in which only half of the animals with the highest tick counts were treated (IPV7S protocol); and Group 3 (non-treated). The protocols were able to maintain low tick infestation during the 57 weeks of study. The two experimental groups showed lower tick counts than the non-treated group, but not between them. Weekly efficacy of the experimental protocols reached 95% in Group 1 and 88% in Group 2. Herein, we proposed two protocols of cattle tick control (IPV6 and IPV7S) for use in multi-resistant tick populations in Southern Brazil.
Assuntos
Acaricidas , Doenças dos Bovinos , Rhipicephalus , Infestações por Carrapato , Acaricidas/farmacologia , Animais , Brasil , Bovinos , Doenças dos Bovinos/prevenção & controle , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/veterináriaRESUMO
Faxinalipterus minimus was originally described as a purported pterosaur from the Late Triassic (early Norian) Caturrita Formation of southern Brazil. Its holotype comprises fragmentary postcranial elements, whereas a partial maxilla was referred to the species. The assignment of Faxinalipterus minimus to Pterosauria has been questioned by some studies, but the specimen has never been accessed in detail after its original description. Here we provide a reassessment of Faxinalipterus minimus after additional mechanical preparation of the holotype. Our interpretations on the identity of several bones differ from those of the original description, and we found no support favoring pterosaur affinities for the taxon. The maxilla previously referred to Faxinalipterus minimus is disassociated from this taxon and referred to a new putative pterosauromorph described here from a partial skull and fragmentary postcranial elements. Maehary bonapartei gen. et sp. nov. comes from the same fossiliferous site that yielded Faxinalipterus minimus, but the lack of overlapping bones hampers comparisons between the two taxa. Our phylogenetic analysis places Faxinalipterus minimus within Lagerpetidae and Maehary bonapartei gen. et sp. nov. as the earliest-diverging member of Pterosauromorpha. Furthermore, the peculiar morphology of the new taxon reveals a new dental morphotype for archosaurs, characterized by conical, unserrated crowns, with a pair of apicobasally oriented grooves. These two enigmatic archosaurs expand our knowledge on the Caturrita Formation fauna and reinforce the importance of its beds on the understanding of Late Triassic ecosystems.
Assuntos
Dinossauros , Fósseis , Animais , Filogenia , Dinossauros/anatomia & histologia , Brasil , Ecossistema , Crânio/anatomia & histologiaRESUMO
Background: Population-based data on epidemiology of Inflammatory Bowel Diseases (IBD) in Brazil are scarce. This study aims to define temporal trends of incidence and prevalence rates of Crohn's disease (CD) and ulcerative colitis (UC) in Brazil. Methods: All IBD patients from the public healthcare national system were included from January 2012 to December 2020. Average Annual Percent Change (AAPC) and 95% confidence intervals (CI) were calculated using log-linear regression for incidence and binomial regression for prevalence. Moran's I autocorrelation index was used to analyse clustering of cities by level of prevalence. Findings: A total of 212,026 IBD patients were included. Incidence of IBD rose from 9.4 in 2012 to 9.6 per 100,000 in 2020 (AAPC=0.8%; 95% CI -0.37, 1.99); for UC, incidence increased from 5.7 to 6.9 per 100,000 (AAPC=3.0%; 95% CI 1.51, 4.58) and for CD incidence decreased from 3.7 to 2.7 per 100,000 (AAPC=-3.2%; 95% CI -4.45, -2.02). Prevalence of IBD increased from 30.0 in 2012 to 100.1 per 100,000 in 2020 (AAPC=14.8%; CI 14.78-14.95); for UC, from 15.7 to 56.5 per 100,000 (AAPC=16.0%; CI 15.94, 16.17); for CD from 12.6 to 33.7 per 100,000 (AAPC=12.1% CI 11.95, 12.02). A south-north gradient was observed in 2020 prevalence rates of IBD [I=0.40 (p<0.0001)], CD [I=0.22 (p<0.0001)] and UC [I=0.42 (p<0.0001)]. Interpretation: Incidence of CD is decreasing whereas of UC is increasing, leading to stabilization in the incidence of IBD from 2012 to 2020 in Brazil. Prevalence of IBD has been climbing with 0.1% of Brazilians living with IBD in 2020. Funding: None.
Assuntos
Rickettsia , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/microbiologia , Animais , Brasil/epidemiologia , História do Século XXI , Humanos , Vigilância da População , Rickettsia/classificação , Rickettsia/genética , Rickettsia/isolamento & purificação , Rickettsiose do Grupo da Febre Maculosa/história , Rickettsiose do Grupo da Febre Maculosa/transmissão , Carrapatos/microbiologiaRESUMO
Amitraz is one of the most used acaricides for the control of ticks of domestic animals, however, extensive use of this active ingredient has favored the development of resistant populations of Rhipicephalus microplus worldwide. The possible mechanisms of metabolic and/or target-site alterations mechanisms of amitraz resistance were investigated in a Brazilian field population of R. microplus (São Gabriel strain). Bioassays with the synergists piperonylbutoxide, triphenylphosphate and diethyl-maleate were used to evaluate the metabolic mechanisms involved. Target-site insensitivity was investigated by amplification and sequencing of a fragment of the octopamine/tyramine (OCT/TYR) receptor gene. Piperonylbutoxide synergism (synergism ratio = 2.8) indicated the participation of the P450 pathway in the detoxification of amitraz. Previously reported single nucleotide polymorphisms that confer amino acid changes in the OCT/TYR receptor, threonine to proline (T8P) and leucine to serine (L22S), were found in the amitraz-resistant strain but not in the susceptible reference strain. The results suggest that amitraz resistance in the studied strain is multi-factorial and may result from cytochrome P450 detoxification and mutations in octopamine receptors.
Assuntos
Acaricidas/farmacologia , Resistência a Medicamentos , Rhipicephalus/efeitos dos fármacos , Toluidinas/farmacologia , Animais , Brasil , FemininoRESUMO
The study of vectors and vector-borne diseases associated with ectoparasites from free-living Neotropical small wild felids is scarce, and the few existing studies on this theme focused on the genus Panthera, Paleartic species or in captive animals. For this reason, the aim of this study was to identify the diversity of ectoparasites and potentially associated Rickettsia and Bartonella species in free-ranging neotropical wild cats collected in the State of Rio Grande do Sul, southern Brazil. A total of 82 ticks, 10 fleas and 22 mites were collected from 18 Geoffroy's cats (Leopardus geoffroyi), 11 margays (Leopardus wiedii), two southern tiger cats (Leopardus guttulus), two jaguarundis (Herpailurus yagouaroundi), three ocelots (Leopardus pardalis) and two pumas (Puma concolor). We identified four tick species: Rhipicephalus microplus and three species from genus Amblyomma, the most frequent being Amblyomma aureolatum; three flea species corresponding to Ctenocephalides felis, Xenopsylla cheopis, and Pulex irritans; and one mite of genus Eutrombicula. In ectoparasites we found DNA of Rickettsia parkeri and Rickettsia asembonensis in ticks and DNA of Bartonella clarridgeiae, Bartonella sp. and R. asembonensis in fleas. Our results highlight the evidences of vectors and vector-borne agents in wild animals, and their potential wide distribution in the Pampa biome and the southernmost portion of the Atlantic Rainforest in Brazil.
Assuntos
Felidae , Ácaros/fisiologia , Sifonápteros/fisiologia , Carrapatos/fisiologia , Doenças Transmitidas por Vetores/veterinária , Animais , Brasil/epidemiologia , Prevalência , Doenças Transmitidas por Vetores/epidemiologia , Doenças Transmitidas por Vetores/microbiologia , Doenças Transmitidas por Vetores/parasitologiaRESUMO
In this work we performed a field study in a spotted fever-endemic area of the Pampa biome in Rio Grande do Sul, the southernmost state of Brazil (Rosário do Sul municipality), with the aim to evaluate the serological status of dogs for spotted fever group (SFG) rickettsiae, to attempt the isolation rickettsiae from A. tigrinum ticks, and to further perform a multi-genic molecular characterization of the rickettsial isolate. For this purpose, we collected blood serum samples and ticks from 18 rural dogs during 2016-2017. By immunofluorescence assay, all 18 dogs (100%) reacted serologically to SFG rickettsiae, with highest endpoint titers to R. parkeri, suggesting that at least part of these dogs have been infected by R. parkeri. Among 23 ticks collected from the dogs (13 A. tigrinum and 10 Rhipicephalus sanguineus sensu stricto), 46% (6/13) A. tigrinum contained DNA of R. parkeri, which was successfully isolated in Vero cell culture from one of these ticks. Partial sequences of five genes (gltA, ompA, virB4, dnaA, dnaK) and 3 intergenic spacers (mppA-purC, rrl-rrf-ITS, rpmE-tRNAfMet) were generated from this rickettsial isolate, and were all 100% identical to corresponding sequences of R. parkeri s.s. We provide the first report of a viable isolate of R. parkeri from A. tigrinum, confirming that this isolate belongs to the strain R. parkeri s.s., as it has already been demonstrated for other two tick species of the Amblyomma maculatum species complex (A. maculatum and Amblyomma triste).
Assuntos
Doenças do Cão/epidemiologia , Infecções por Rickettsia/veterinária , Rickettsia/isolamento & purificação , Animais , Brasil/epidemiologia , Doenças do Cão/microbiologia , Cães , Ecossistema , Feminino , Rickettsia/genética , Rickettsia/fisiologia , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/microbiologia , Estudos SoroepidemiológicosRESUMO
Leptospirosis is a disease of worldwide distribution that affects man and several animal species. Domestic and wild animals can behave as reservoirs of the agent. The aim of this study was to evaluate the frequency of anti-Leptospira spp. antibodies in dogs and wild small mammals from rural properties and conservation units of three municipalities of Rio Grande do Sul State, Brazil. Sera were collected from 192 domestic dogs and 132 small mammals, namely rodents of the Cricetidae and Caviidae families and marsupials of the Didelphidae family. The study used Microscopic Agglutination Test (MAT) against 23 serovars of Leptospira spp. Overall, 9.90% (19/192) dogs, and 1.51% (2/132) small mammals were seropositive. Leptospira interrogans serovar Australis was the most frequent serovar in dogs and antibodies against L. interrogans serovar Pomona were detected in a dog and a small mammal belonging to the same municipality. We conclude that in the regions studied the frequency of seropositivity in dogs is low, and leptospires do not seem to be circulating in small mammals, yet, further research is necessary to assess the real role that these animals may have for leptospirosis in the studied areas. This is the first serological survey in small mammals, including wild rodents, in the area that encompasses conservation units of great importance to Rio Grande do Sul state.
RESUMO
Phlebotomine sand flies are hematophagous insect vectors of the protozoan parasites of the genus Leishmania Ross, 1903 (Kinetoplastida: Trypanosomatida) that infect mammals, including humans, causing leishmaniasis. In Porto Alegre, Brazil, three autochthonous cases of human visceral leishmaniasis were reported in 2016 through 2017. We analyzed for the presence of Leishmania DNA in sand flies collected at the neighborhood of Agronomia, Porto Alegre, Brazil. Phlebotomine sand flies were collected at three sites from October 2014 to September 2015. Female sand flies were pooled in numbers from 1 to 20 depending upon species, locality, and date; all were screened for Leishmania infection by the amplification of the ITS1 region. In total 518 phlebotomine sand flies were collected: Psathyromyia lanei (Barretto and Coutinho, 1941) (Diptera: Psychodidae) (30.5%), Brumptomyia sp. (França and Parrrot, 1921) (Diptera: Psychodidae) (25.7%), Migonemyia migonei (Franca, 1920) (Diptera: Psychodidae) (21.4%), Pintomyia fischeri (Pinto, 1926) (Diptera: Psychodidae) (21.4%), and Nyssomyia neivai (Pinto, 1926) (Diptera: Psychodidae) (1.0%). Most sand flies were collected during the hot and rainy season from October 2014 to April 2015. Of the 113 pools analyzed, five pools of Pi. fischeri were PCR-positive with the amplicons possessing sequences similar (>95%) to that of Leishmania infantum Nicolle, 1908 (Kinetoplastida: Trypanosomatida). These results represent the first molecular detection of Le. infantum in Pi. fischeri. It is possible that Pi. fischeri is involved in the transmission cycle of Le. infantum in the studied area; however, further studies are needed to establish the true role of Pi. fischeri in the visceral leismaniasis cycle.
Assuntos
Distribuição Animal , Leishmania infantum/isolamento & purificação , Psychodidae/parasitologia , Animais , Brasil , Feminino , Leishmaniose Visceral/transmissão , Masculino , Estações do AnoRESUMO
Anthropogenic contamination of beaches in the south of Brazil was assessed by detection of Escherichia coli, human mastadenovirus species C (HAdV-C) and F (HAdV-F) and hepatitis E virus (HEV). Sampling was carried out in October (2016), and in January, April and July (2017). Water, sediment, sea surface microlayer (SML), bivalves, and air sentinel samples were evaluated. Quantitative microbiological risk assessment (QMRA) was used to estimate the probability of swimmer infection. HAdV-C was present in 26% of the samples, for both qPCR and viral isolation. The highest rates of detection in genomic copies (GC) were in water (2.42E+10 GC/L), SML (2.08E+10 GC/L), sediment (3.82E+08 GC/g) and bivalves (3.91E+07 GC/g). QMRA estimated daily and annual risks with a maximum value (9.99E-01) in almost all of the samples. Viable HAdV-C was often detected in the SML, pointing that this is a source of infection for people bathing in these waters.