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1.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde, LIS-bvsms | ID: lis-LISBR1.1-46893

RESUMO

A Oncocercose é uma doença parasitária crônica decorrente da infecção produzida pelo nematódeo Onchocerca volvulus, que se localiza no tecido subcutâneo das pessoas atingidas. A causa principal é a picada do inseto conhecido como borrachudo ou pium infectado com larvas do parasita.


Assuntos
Oncocercose , Doenças Parasitárias , Parasitos , Insetos Vetores , Simuliidae
2.
Mem Inst Oswaldo Cruz ; 114: e190184, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576903

RESUMO

American visceral leishmaniasis (AVL) has two main scenarios of transmission as follows: scattered cases in rural areas and urban outbreaks. Urban AVL is in active dispersion from the northeastern border of Argentina-Paraguay-Brazil to the South. The presence of Lutzomyia longipalpis was initially reported in urban environments in the northwestern border of the country. The presence of Lu. longipalpis, environmental variables associated with its distribution, and its genetic diversity were assessed in Salvador Mazza, Argentina, on the border with Bolivia. The genetic analysis showed high haplotype diversity, low nucleotide diversity, and low nucleotide polymorphism index. We discuss the hypothesis of an expanding urban population with introgressive hybridisation of older haplogroups found in their path in natural forest or rural environments, acquiring a new adaptability to urban environments, and the possibility of changes in vector capacity.


Assuntos
Distribuição Animal , Variação Genética/genética , Insetos Vetores/genética , Psychodidae/genética , Animais , Argentina , Bolívia , Brasil , DNA Mitocondrial/genética , Genes de Insetos/genética , Haplótipos , Insetos Vetores/classificação , Leishmaniose Cutânea/transmissão , Masculino , Filogeografia , Psychodidae/classificação
3.
Rev Inst Med Trop Sao Paulo ; 61: e47, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31531625

RESUMO

Triatomines are vectors of Trypanosoma cruzi , the etiological agent of Chagas disease, which affects between 6 and 12 million people in Latin America, with an incidence rate of 12 thousand cases per year. In the Ceara State, the predominance of the caatinga biome, coupled with a large rural area with precarious human habitations, provides several s shelters for these insects. In this study, we determined the spatiotemporal distribution of triatomine dispersion rates in the Cariri region, Southern Ceara and ascertained the possible association between these rates with socioeconomic and environmental factors. Dispersion rates (number of positive localities/number of searched localities × 100) were analyzed regarding 13 municipalities from the Ceara State, from 2009 to 2013. Socioeconomic and environmental variables collected from national research institutes were associated with the dispersion rates and their local empirical Bayesian estimates. All the municipalities recorded dispersion rates over 10% in all years, and 11 municipalities had average rates over 40% for the period of study. Significant differences were observed among the municipality means. The highest rates were observed in Antonina do Norte and Potengi. According to the correlation analysis, the proportion between the occupied population and the total population showed a significant negative correlation, as well as the percentage of the population who lives under adequate sanitary conditions. Both, the percentage of revenues from external sources and the percentage of urban households in reforested blocks had a significant positive correlation. Our results show that socioeconomic and environmental variables can be factors that contribute to both, the maintenance and the reduction of the elevated dispersion rates observed in the study area. Similar researches that encompass more municipalities from that region may reinforce Chagas disease surveillance and control in the Northeast of Brazil.


Assuntos
Habitação , Insetos Vetores/classificação , Triatominae/classificação , Animais , Teorema de Bayes , Brasil , Doença de Chagas/transmissão , Meio Ambiente , Humanos , Densidade Demográfica , Dinâmica Populacional , Fatores Socioeconômicos
4.
Braz J Med Biol Res ; 52(9): e8224, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482975

RESUMO

Leishmaniasis is a neglected disease that affects a large part of the world population. Knowing the sand fly fauna of a region is of fundamental importance for guiding health surveillance actions related to the prevention and control of leishmaniasis. A total of 86 specimens of sand flies (60 females and 26 males) were collected. Using the classification proposed by Galati (2003), the following species were identified: Lutzomyia longipalpis (Lutz & Neiva, 1912), Migonemyia migonei (França, 1920), Evandromyia cortelezzi (Brethes, 1923), Ev. sallesi (Galvão & Coutinho, 1939), Nyssomyia whitmani (Atunes & Coutinho, 1939), Psathyromyia lutziana (Costa Lima, 1932), Ev. lenti (Mangabeira, 1938), Brumptomyia sp. (França and Parrot, 1921), and Pressatia sp. (Mangabeira, 1942). Using PCR with internal transcribed spacer target to identify infected sand flies, five Lu. longipalpis females were infected with Leishmania spp. Despite the small number of specimens collected, considerable species diversity was found in the study area.


Assuntos
Insetos Vetores/classificação , Insetos Vetores/parasitologia , Leishmania/isolamento & purificação , Psychodidae/classificação , Psychodidae/parasitologia , Animais , Brasil , DNA Espaçador Ribossômico/genética , Feminino , Leishmania/genética , Leishmaniose/transmissão , Masculino , Reação em Cadeia da Polimerase , RNA de Protozoário/genética
6.
Mem Inst Oswaldo Cruz ; 114: e190034, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31433005

RESUMO

Six Phlebotominae sand fly species are incriminated as biological vectors of human pathogens in Panama, but molecular corroboration is still needed. We aim at confirming the identity of Phlebotominae species documented as anthropophilic in Panama. Adult sandflies were collected from August 2010 to February 2012 in Central Panama using CDC light traps. Species confirmation was accomplished through molecular barcodes and allied sequences from GenBank. A total of 53,366 sand fly specimens representing 18 species were collected. Five species were validated molecularly as single phylogenetic clusters, but Psychodopygus thula depicted two genetically divergent lineages, which may be indicative of cryptic speciation.


Assuntos
Biodiversidade , Insetos Vetores/genética , Psychodidae/genética , Animais , Insetos Vetores/classificação , Leishmaniose Cutânea/transmissão , Panamá , Filogenia , Psychodidae/classificação
7.
Arch Virol ; 164(11): 2799-2804, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31440810

RESUMO

Thrips palmi transmits the tospoviruses watermelon bud necrosis (WBNV) and groundnut bud necrosis virus (GBNV) in persistent propagative way. Little is known about the T. palmi-WBNV and -GBNV relationship. In this study, we report the effects of WBNV and GBNV infection on the life history traits of T. palmi. Both WBNV and GBNV had some negative effects on the adult life span, fecundity and survival of T. palmi as compared to non-exposed T. palmi. Tospovirus exposure favoured a female-biased ratio in the experimental population.


Assuntos
Insetos Vetores/virologia , Doenças das Plantas/virologia , Tisanópteros/virologia , Tospovirus/crescimento & desenvolvimento , Animais , Feminino , Masculino , Plantas/virologia , Tospovirus/genética
8.
Mem Inst Oswaldo Cruz ; 114: e190170, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31365633

RESUMO

BACKGROUND: The state of Rondônia (RO) is a hot spot for human cases of cutaneous leishmaniasis. Many sandfly species in RO are putative vectors of leishmaniasis. OBJECTIVES: This study examines the diversity patterns and the presence of Leishmania DNA and blood meal sources of sandflies in RO. METHODS: A sandfly survey was performed between 2016 and 2018 in 10 municipalities categorised into three different environment types: (i) Conservation Unit (CUN) - comprised of preserved ombrophilous forests; (ii) Forest Edge (FE) - small forest fragments; and (iii) Peridomicile (PE) - areas around dwellings. FINDINGS: A total of 73 species were identified from 9,535 sandflies. The most abundant species were Psychodopygus davisi (1,741 individuals), Nyssomyia antunesi (1,397), Trichophoromyia auraensis (1,295) and Trichophoromyia ubiquitalis (1,043). Diversity was the highest in CUN, followed by the FE and PE environments. One pool of Ps. davisi tested positive for Leishmania braziliensis, reinforcing the possibility that Ps. davisi acts as a vector. The cytochrome b (cytb) sequences were used to identify three blood meal sources: Bos taurus, Homo sapiens and Tamandua tetradactyla. MAIN CONCLUSIONS: Our results demonstrated that sandflies can switch between blood meal sources in differing environments. This study enhances the knowledge of the vector life cycle in RO and provides information relevant to leishmaniasis surveillance.


Assuntos
Reservatórios de Doenças/parasitologia , Insetos Vetores/fisiologia , Leishmaniose Cutânea/transmissão , Psychodidae/parasitologia , Animais , Animais Domésticos/parasitologia , Brasil/epidemiologia , Feminino , Florestas , Humanos , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/veterinária , Masculino , Densidade Demográfica , População Urbana
9.
Rev Inst Med Trop Sao Paulo ; 61: e38, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31411268

RESUMO

The triatomine insect Panstrongylus megistus , one of the most important Chagas disease vectors in Brazil, presents salivary molecules pharmacologically active to counteract homeostatic responses from the host, including inhibitors of the human complement system, a major effector of immune responses. The aim of the present study was to investigate the effect of P. megistus salivary gland extract (SGE) on the complement system from different host species and characterize the inhibitory effect of SGE and intestinal contents on human complement. Glands and midguts from fourth instar nymphs were used. Hemolytic assays were performed with sheep erythrocytes as complement activators by using human, rats and chickens sera in the presence or absence of SGE. An ELISA assay was carried out detect deposition of the C3b component on IgG- or agarose-sensitized microplates, in the presence or absence of SGE or midgut contents. P. megistus SGE was able to significantly inhibit the complement of the three studied species (human, rat and chiken). Both, SGE and midgut contents inhibited C3b deposition in either the classical or the alternative pathways. As conclusions, SGE and midgut from P. megistus possess anti-complement activity. The inhibitors are effective against different host species and act on the initial steps of the complement system cascade. These inhibitors may have a role in blood feeding and Trypanosoma cruzi transmission by the vector.


Assuntos
Proteínas do Sistema Complemento/efeitos dos fármacos , Sistema Digestório/química , Insetos Vetores , Panstrongylus , Glândulas Salivares/química , Animais , Doença de Chagas/transmissão , Galinhas , Humanos , Ratos , Ovinos
10.
Plant Dis ; 103(9): 2184-2190, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31287372

RESUMO

Little cherry disease (LCD) threatens the long-term economic sustainability of the Pacific Northwest sweet cherry (Prunus avium) industry. Results from a series of partial budget analyses indicate that additional investments in monitoring, testing, spraying to control for insect vectors, and removing infected trees are lower than the reduced profit losses compared with the do-nothing scenario. Also, management can prevent or lessen the negative impacts of higher little cherry virus (Velarivirus little cherry virus 1, Ampelovirus little cherry virus 2) spread rates. Our findings illustrate the importance of prevention, correct identification, and controlling for insect vectors in preventing the dissemination of LCD, for which the only known treatment is tree removal.


Assuntos
Agricultura , Closteroviridae , Doenças das Plantas , Prunus avium , Agricultura/métodos , Animais , Closteroviridae/fisiologia , Frutas , Controle de Insetos , Insetos Vetores/fisiologia , Doenças das Plantas/prevenção & controle , Prunus avium/virologia , Washington
11.
Rev Soc Bras Med Trop ; 52: e20190063, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31271624

RESUMO

INTRODUCTION: The present study reports the presence of triatomines in natural, peridomestic, and intradomicile environments in Itacoatiara municipality, state of Amazonas, a non-endemic region for Chagas disease. METHODS: Active search was performed inside tree trunks, and palm trees, residences, and peridomiciles localized near the forest area. RESULTS: Twenty adults and ten triatomines nymphs were collected, fifteen of which were from natural forests, thirteen from intradomiciles, and two from peridomicile areas. CONCLUSIONS: The new records of adults and nymphs of triatomines in the intra- and peridomiciles suggest the adoption of prophylactic measures for vector surveillance in the study area.


Assuntos
Insetos Vetores/parasitologia , Triatominae/parasitologia , Distribuição Animal , Animais , Brasil , Doença de Chagas/transmissão , Feminino , Florestas , Habitação , Insetos Vetores/classificação , Densidade Demográfica , Triatominae/classificação , Trypanosoma cruzi/isolamento & purificação
12.
Rev Soc Bras Med Trop ; 52: e20190061, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31340365

RESUMO

INTRODUCTION: The ecoepidemiological situation in the State of Rio Grande do Norte, Brazil is characterized by frequent invasion and colonization of domiciliary units (DUs) by several triatomine species, with high rates of natural infection by Trypanosoma cruzi. METHODS: We evaluated the possibility of vector transmission of T. cruzi based on records of the occurrence of domiciled triatomines collected by the Secretariat of State for Public Health from 2005 to 2015. During this period, 67.7% (113/167) of municipalities conducted at least one active search and 110 recorded the presence of insects in DUs. These activities were more frequent in municipalities considered to have a high and medium-level risk of T. cruzi transmission. RESULTS: Of 51,569 captured triatomines, the most common species were Triatoma brasiliensis (47.2%) and T. pseudomaculata (40.2%). Colonies of T. brasiliensis, T. pseudomaculata, T. petrocchiae, Panstrongylus lutzi, and Rhodnius nasutus were also recorded in the intradomicile and peridomicile. Natural infection by trypanosomatids was detected in 1,153 specimens; the highest rate was found in R. nasutus (3.5%), followed by T. brasiliensis (2.5%) and T. pseudomaculata (2.4%). There have been high levels of colonization over the years; however, not all infested DUs have been sprayed. CONCLUSIONS: This is the first report of intradomicile and peridomicile colonization by P. lutzi. These results demonstrate the risk of new cases of infection by T. cruzi and reinforce the need for continuous entomological surveillance in the State of Rio Grande do Norte.


Assuntos
Doença de Chagas/transmissão , Insetos Vetores/parasitologia , Triatominae/parasitologia , Trypanosoma cruzi/isolamento & purificação , Animais , Brasil , Doença de Chagas/prevenção & controle , Entomologia , Insetos Vetores/classificação , Análise Espacial , Triatominae/classificação
13.
Parasite ; 26: 38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31259684

RESUMO

An inventory of Phlebotomine sandflies was carried out in the Ankarana tsingy located in far northern Madagascar. A total of 723 sandflies were used for morphological, morphometric, and molecular studies (sequencing of partial cytochrome B (mtDNA) and partial 28S (rDNA)). Nine species were identified: Phlebotomus fertei, Sergentomyia anka, Se. sclerosiphon, Se. goodmani, two species of the genus Grassomyia, as well as three new species described herein: Se. volfi n. sp., Se. kaltenbachi n. sp., and Se. ozbeli n. sp. The recognition of these new species is strongly supported by molecular analyses. The first two of the new species could not be classified into any existing subgenus, therefore we proposed two new subgenera (Ranavalonomyia subg. nov., and Riouxomyia subg. nov.), with combinations as: Sergentomyia (Ranavalonomyia) volfi and Sergentomyia (Riouxomyia) kaltenbachi. Our study reveals important molecular variability in Se. anka, with the recognition of a population whose taxonomic status remains below that of species. Our research confirms the need to further study the specific diversity of Malagasy sandflies, which until the start of this millennium remained mostly unknown.


Assuntos
Phlebotomus/classificação , Filogenia , Animais , Citocromos b/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Feminino , Variação Genética , Insetos Vetores/classificação , Madagáscar , Masculino , Especificidade da Espécie
14.
Virology ; 533: 137-144, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31247402

RESUMO

Angiotensin-converting enzyme (ACE) plays diverse roles in the animal kingdom. However, whether ACE plays an immune function against viral infection in vector insects is unclear. In this study, an ACE gene (LsACE) from the small brown planthopper was found to respond to Rice stripe virus (RSV) infection. The enzymatic activities of LsACE were characterized at different pH and temperature. Twenty planthopper proteins were found to interact with LsACE. RSV infection significantly upregulated LsACE expression in the testicle and fat body. When the expression of LsACE in viruliferous planthoppers was inhibited, the RNA level of the RSV SP gene was upregulated 2-fold in planthoppers, and all RSV genes showed higher RNA levels in the rice plants consumed by these planthoppers, leading to a higher viral infection rate and disease rating index. These results indicate that LsACE plays a role in the immune response against RSV transmission by planthoppers.


Assuntos
Hemípteros/imunologia , Hemípteros/virologia , Proteínas de Insetos/imunologia , Insetos Vetores/imunologia , Insetos Vetores/virologia , Peptidil Dipeptidase A/imunologia , Tenuivirus/fisiologia , Sequência de Aminoácidos , Animais , Hemípteros/genética , Hemípteros/fisiologia , Proteínas de Insetos/genética , Insetos Vetores/genética , Insetos Vetores/fisiologia , Oryza/virologia , Peptidil Dipeptidase A/genética , Filogenia , Doenças das Plantas/virologia , Tenuivirus/classificação , Tenuivirus/genética , Tenuivirus/isolamento & purificação
15.
BMC Infect Dis ; 19(1): 493, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164093

RESUMO

BACKGROUND: Dengue is becoming a major public health concern in Guangdong (GD) Province of China. The problem was highlighted in 2014 by an unprecedented explosive outbreak, where the number of cases was larger than the total cases in previous 30 years. The present study aimed to clarify the spatial and temporal patterns of this dengue outbreak. METHODS: Based on the district/county-level epidemiological, demographic and geographic data, we first used Moran's I statistics and Spatial scan method to uncover spatial autocorrelation and clustering of dengue incidence, and then estimated the spatial distributions of mosquito ovitrap index (MOI) by using inverse distance weighting. We finally employed a multivariate time series model to quantitatively decompose dengue cases into endemic, autoregressive and spatiotemporal components. RESULTS: The results indicated that dengue incidence was highly spatial-autocorrelated with the inclination of clustering and nonuniformity. About 12 dengue clusters were discovered around Guangzhou and Foshan with significant differences by district/county, where the most likely cluster with the largest relative risk located in central Guangzhou in October. Three significant high-MOI areas were observed around Shaoguan, Qingyuan, Shanwei and Guangzhou. It was further found the districts in Guagnzhou and Foshan were prone to local autoregressive transmission, and most region in southern and central GD exhibited higher endemic components. Moreover, nearly all of districts/counties (especially the urban area) have cases that were infected in adjacent regions. CONCLUSIONS: The study can help to clarify the heterogeneity and the associations of dengue transmission in space and time, and thus provide useful information for public health authorities to plan dengue control strategies.


Assuntos
Dengue/epidemiologia , Surtos de Doenças , Animais , China/epidemiologia , Análise por Conglomerados , Culicidae/virologia , Dengue/transmissão , Humanos , Incidência , Insetos Vetores/virologia , Estudos Retrospectivos , Análise Espacial , Análise Espaço-Temporal
16.
Environ Monit Assess ; 191(Suppl 2): 331, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31254126

RESUMO

Visceral leishmaniasis is a public health problem in Brazil. This disease is endemic in most of Bahia state, with increasing reports of cases in new areas. Ecological niche models (ENM) can be used as a tool for predicting potential distribution for disease, vectors, and to identify risk factors associated with their distribution. In this study, ecological niche models (ENMs) were developed for visceral leishmaniasis (VL) cases and 12 sand fly species captured in Bahia state. Sand fly data was collected monthly by CDC light traps from July 2009 to December 2012. MODIS satellite imagery was used to calculate NDVI, NDMI, and NDWI vegetation indices, MODIS day and night land surface temperature (LST), enhanced vegetation index (EVI), and 19 Bioclim variables were used to develop the ENM using the maximum entropy approach (Maxent). Mean diurnal range was the variable that most contributed to all the models for sand flies, followed by precipitation in wettest month. For Lutzomyia longipalpis (L. longipalpis), annual precipitation, precipitation in wettest quarter, precipitation in wettest month, and NDVI were the most contributing variables. For the VL model, the variables that contributed most were precipitation in wettest month, annual precipitation, LST day, and temperature seasonality. L. longipalpis was the species with the widest potential distribution in the state. The identification of risk areas and factors associated with this distribution is fundamental to prioritize resource allocation and to improve the efficacy of the state's program for surveillance and control of VL.


Assuntos
Ecossistema , Insetos Vetores/fisiologia , Leishmaniose Visceral/transmissão , Psychodidae/fisiologia , Animais , Brasil/epidemiologia , Monitoramento Ambiental/estatística & dados numéricos , Geografia Médica , Insetos Vetores/classificação , Leishmaniose Visceral/epidemiologia , Psychodidae/classificação , Chuva , Temperatura Ambiente
17.
Onderstepoort J Vet Res ; 86(1): e1-e6, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31170783

RESUMO

African animal trypanosomosis (AAT) is caused by several species of the genus Trypanosoma, a parasitic protozoan infecting domestic and wild animals. One of the major effects of infection with pathogenic trypanosome is anaemia. Currently, the control policies for tsetse and trypanosomosis are less effective in South Africa. The only response was to block treat all infected herds and change the dip chemical to one which controls tsetse flies during severe outbreaks. This policy proved to be less effective as demonstrated by the current high level of trypanosome infections in cattle. Our objective was to study the impacts of AAT (nagana) on animal productivity by monitoring the health of cattle herds kept in tsetse and trypanosomosis endemic areas before and after an intervention that reduces the incidence of the disease. The study was conducted on a farm in northern KwaZulu-Natal which kept a commercial cattle herd. There was no history of any cattle treatment for trypanosome. All cattle were generally in poor health condition at the start of the study though the herd received regular anthelminthic treatment. A treatment strategy using two drugs, homidium bromide (ethidium) and homidium chloride (novidium), was implemented. Cattle were monitored regularly for 13 months for herd trypanosomosis prevalence (HP), herd average packed cell volume (H-PCV) and the percentage of the herd that was anaemic (HA). A total of six odour-baited H-traps were deployed where cattle grazed from January 2006 to August 2007 to monitor the tsetse population. Glossina brevipalpis Newstead and Glossina austeni Newstead were collected continuously for the entire study period. High trypanosomes HP (44%), low average H-PCV (29.5) and HA (24%) were rerecorded in the baseline survey. All cattle in the herd received their first treatment with ethidium bromide. Regular monthly sampling of cattle for the next 142 days showed a decline in HP of 2.2% - 2.8%. However, an HP of 20% was recorded by day 220 and the herd received the second treatment using novidium chloride. The HP dropped to 0.0% and HA to 0.0% by day 116 after the second treatment. The cow group was treated again by day 160 when the HP and HA were 27.3% and 11%, respectively. The same strategy was applied to the other two groups of weaners and the calves at the time when their HP reached 20%. Ethidium and novidium treatment protected cattle, that were under continuous tsetse and trypanosomosis challenge, for up to 6 months. Two to three treatments per year may be sufficient for extended protection. However, this strategy would need to be included into an integrated pest management approach combining vector control for it to be sustainable.


Assuntos
Criação de Animais Domésticos , Anti-Helmínticos/uso terapêutico , Doenças dos Bovinos/tratamento farmacológico , Controle de Insetos , Tripanossomíase Africana/veterinária , Animais , Anti-Helmínticos/administração & dosagem , Bovinos , Doenças dos Bovinos/epidemiologia , Esquema de Medicação/veterinária , Fazendas , Insetos Vetores , África do Sul/epidemiologia , Resultado do Tratamento , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Bovina/tratamento farmacológico , Moscas Tsé-Tsé
18.
An Acad Bras Cienc ; 91 Suppl 3: e20190122, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31166476

RESUMO

Insects are the most diverse group of animals. They can be infected by an extraordinary diversity of viruses. Among them, arthropod-borne viruses (arboviruses) can be transmitted to humans. High-throughput sequencing of small RNAs from insects provides insight into their virome, which may help understand the dynamics of vector borne infectious diseases. Furthermore, investigating the mechanisms that restrict viral infections in insects points to genetic innovations that may inspire novel antiviral strategies.


Assuntos
Biodiversidade , Genoma Viral/genética , Insetos Vetores/virologia , Vírus dos Insetos/classificação , Vírus de RNA/classificação , Animais , Insetos Vetores/classificação , Vírus dos Insetos/genética , Vírus de RNA/genética
19.
Rev Soc Bras Med Trop ; 52: e20180464, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31188913

RESUMO

INTRODUCTION: Nyssomyia intermedia is an important vector of American cutaneous leishmaniasis. METHODS: Sand flies were captured in a Shannon trap and after landing on human collectors and retrieved monthly. Nocturnal activity was estimated using a log-linear model. RESULTS: Peak sand fly collection in the Shannon trap occurred in summer and winter, and peak fly collection on humans occurred in spring and summer. CONCLUSIONS: Ny. intermedia was captured in both the hottest and coldest months, indicating its adaptability to different seasons and the possibility of disease transmission at any time of the year in Campus Fiocruz Mata Atlântica, Brazil.


Assuntos
Ciclos de Atividade/fisiologia , Insetos Vetores/fisiologia , Leishmaniose Cutânea/transmissão , Psychodidae/fisiologia , Animais , Brasil , Florestas , Psychodidae/classificação , Estações do Ano
20.
Parasit Vectors ; 12(1): 291, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182163

RESUMO

BACKGROUND: Chagas disease remains a major public health risk in Bolivia, particularly among rural indigenous communities. Here we studied the cultural perception of the triatomine vectors and Chagas disease among selected rural and urban ethnic groups from different socio-economic and geographical milieus. We focused on the indigenous communities in the Bolivian Chaco where the disease is hyperendemic. METHODS: A cross-sectional study using field observations and structured interviews was carried out among 480 informants in five different regions of Bolivia. Additional semi-structured interviews were conducted. Statistical analyses were performed to determine the correlation of socio-economic variables and indigenous Chagas disease knowledge systems. A total of 170 domestic Triatoma infestans vectors were collected and infection with Trypanosoma cruzi was analyzed by real-time PCR. RESULTS: Triatomine bugs were associated with Chagas disease in 70.2% (n = 480) of the responses (48.0% Ayoreo, 87.5% Chiquitano, 83.9% Guaraní, 72.2% Quechua, 46.1% La Paz citizens and 67.7% Santa Cruz citizens). Generally, indigenous informants have been educated on the association between triatomine bugs and Chagas disease by institutional anti-Chagas disease campaigns. While communities were largely aware of the vectors as a principal mode of disease transmission, rather unexpectedly, health campaigns had little influence on their prevention practices, apparently due to cultural constraints. Overall, 71.9% of the collected domestic vectors in the Chaco region were infected with T. cruzi, matching the high infection rates in the indigenous communities. CONCLUSIONS: Among the Guaraní, Ayoreo and Quechua communities, the groups living in traditional houses have not integrated the scientific knowledge about Chagas disease transmission into their daily hygiene and continue to cohabit with T. infestans vectors hyperinfected with T. cruzi. An effective translation of Western disease concepts into traditional preventive measures is missing because asymptomatic infections are not generally perceived as threat by the communities. New participatory approaches involving existing ethnomedical knowledge systems could be a successful strategy in the control of T. cruzi infection.


Assuntos
Doença de Chagas/epidemiologia , Cultura , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Grupos Populacionais , Triatoma/parasitologia , Adulto , Animais , Bolívia/epidemiologia , Doença de Chagas/prevenção & controle , Estudos Transversais , Feminino , Geografia , Humanos , Insetos Vetores/parasitologia , Masculino , População Rural , Fatores Socioeconômicos , Inquéritos e Questionários , Trypanosoma cruzi , População Urbana
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