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1.
PLoS One ; 17(2): e0263929, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35167622

RESUMO

BACKGROUND: Despite twelve rounds of school-based preventive chemotherapy for schistosomiasis in endemic areas of Tanzania such as Mtama district, Lindi: the burden of Schistosoma haematobium infection has remained highly conceivable due to re-infections. The factors associated with continuity of S.haematobium transmission in Mtama district, Lindi have not been fully established. This study investigated the burden and factors contributing to the ongoing transmission of S.haematobium infection in the endemic district of Mtama, Lindi. METHODS: A quantitative cross-sectional survey was carried out among 649 school-age children in the Mtama district to determine the burden and factors associated with continuity of S.haematobium infection transmission. A single urine specimen was obtained from each pupil and tested for macro- and microhaematuria, presence of S.haematobium ova, as well intensity of infection; this was complemented with a survey of Bulinus spp snail intermediate hosts and their infectivity. A structured questionnaire was employed to gather information on individual and environmental risk factors for S.haematobium transmission. Summary statistics were computed for individual variables; while a univariate and multivariate logistic regression analysis was performed to assess the association between risk factors with S.haematobium infection. RESULTS: Prevalence of S.haematobium infection by macro- and microhaematuria was 13.1% and 46.2% respectively. The prevalence of S.haematobium ova was 52.7%; intensity of infection was light in 53.1%, and heavy in 46.9%. Snail intermediate hosts were Bulinus globosus and B.nasutus, whose infectivity was 2.2% and 1.3%, respectively. Among the assessed risk factors, long residency (10-13 years) in the area was a significant risk factor for the continuity of S.haematobium transmission (AOR: 21.79, 95% CI: 1.37-346.4). CONCLUSIONS: The observed 52.7% prevalence of S.haematobium infection represents unacceptably high prevalence after 12 rounds of preventive chemotherapy. Therefore, an urgent need for the implementation of integrated multiple control interventions in the Mtama district; is considered to be imperative.


Assuntos
Schistosoma haematobium/isolamento & purificação , Esquistossomose Urinária/epidemiologia , Esquistossomose Urinária/transmissão , Caramujos/classificação , Adolescente , Animais , Criança , Estudos Transversais , Vetores de Doenças/classificação , Doenças Endêmicas , Feminino , Humanos , Modelos Logísticos , Masculino , Prevalência , Fatores de Risco , Esquistossomose Urinária/urina , Serviços de Saúde Escolar , Instituições Acadêmicas , Caramujos/parasitologia , Tanzânia/epidemiologia
2.
Nucleic Acids Res ; 50(D1): D898-D911, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34718728

RESUMO

The Eukaryotic Pathogen, Vector and Host Informatics Resource (VEuPathDB, https://veupathdb.org) represents the 2019 merger of VectorBase with the EuPathDB projects. As a Bioinformatics Resource Center funded by the National Institutes of Health, with additional support from the Welllcome Trust, VEuPathDB supports >500 organisms comprising invertebrate vectors, eukaryotic pathogens (protists and fungi) and relevant free-living or non-pathogenic species or hosts. Designed to empower researchers with access to Omics data and bioinformatic analyses, VEuPathDB projects integrate >1700 pre-analysed datasets (and associated metadata) with advanced search capabilities, visualizations, and analysis tools in a graphic interface. Diverse data types are analysed with standardized workflows including an in-house OrthoMCL algorithm for predicting orthology. Comparisons are easily made across datasets, data types and organisms in this unique data mining platform. A new site-wide search facilitates access for both experienced and novice users. Upgraded infrastructure and workflows support numerous updates to the web interface, tools, searches and strategies, and Galaxy workspace where users can privately analyse their own data. Forthcoming upgrades include cloud-ready application architecture, expanded support for the Galaxy workspace, tools for interrogating host-pathogen interactions, and improved interactions with affiliated databases (ClinEpiDB, MicrobiomeDB) and other scientific resources, and increased interoperability with the Bacterial & Viral BRC.


Assuntos
Bases de Dados Factuais , Vetores de Doenças/classificação , Interações Hospedeiro-Patógeno/genética , Fenótipo , Interface Usuário-Computador , Animais , Apicomplexa/classificação , Apicomplexa/genética , Apicomplexa/patogenicidade , Bactérias/classificação , Bactérias/genética , Bactérias/patogenicidade , Doenças Transmissíveis/microbiologia , Doenças Transmissíveis/parasitologia , Doenças Transmissíveis/patologia , Doenças Transmissíveis/transmissão , Biologia Computacional/métodos , Mineração de Dados/métodos , Diplomonadida/classificação , Diplomonadida/genética , Diplomonadida/patogenicidade , Fungos/classificação , Fungos/genética , Fungos/patogenicidade , Humanos , Insetos/classificação , Insetos/genética , Insetos/patogenicidade , Internet , Nematoides/classificação , Nematoides/genética , Nematoides/patogenicidade , Filogenia , Virulência , Fluxo de Trabalho
3.
Nucleic Acids Res ; 50(D1): D943-D949, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34634795

RESUMO

Emerging infectious diseases significantly threaten global public health and socioeconomic security. The majority of emerging infectious disease outbreaks are caused by zoonotic/vector-borne viruses. Bats and rodents are the two most important reservoir hosts of many zoonotic viruses that can cross species barriers to infect humans, whereas mosquitos and ticks are well-established major vectors of many arboviral diseases. Moreover, some emerging zoonotic diseases require a vector to spread or are intrinsically vector-borne and zoonotically transmitted. In this study, we present a newly upgraded database of zoonotic and vector-borne viruses designated ZOVER (http://www.mgc.ac.cn/ZOVER). It incorporates two previously released databases, DBatVir and DRodVir, for bat- and rodent-associated viruses, respectively, and further collects up-to-date knowledge on mosquito- and tick-associated viruses to establish a comprehensive online resource for zoonotic and vector-borne viruses. Additionally, it integrates a set of online visualization tools for convenient comparative analyses to facilitate the discovery of potential patterns of virome diversity and ecological characteristics between/within different viral hosts/vectors. The ZOVER database will be a valuable resource for virologists, zoologists and epidemiologists to better understand the diversity and dynamics of zoonotic and vector-borne viruses and conduct effective surveillance to monitor potential interspecies spillover for efficient prevention and control of future emerging zoonotic diseases.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Bases de Dados Factuais , Software , Viroses/epidemiologia , Vírus/patogenicidade , Zoonoses/epidemiologia , Animais , Quirópteros/virologia , Doenças Transmissíveis Emergentes/transmissão , Doenças Transmissíveis Emergentes/virologia , Culicidae/virologia , Conjuntos de Dados como Assunto , Vetores de Doenças/classificação , Monitoramento Epidemiológico , Interações Hospedeiro-Patógeno , Humanos , Internet , Anotação de Sequência Molecular , Roedores/virologia , Carrapatos/virologia , Viroses/transmissão , Viroses/virologia , Vírus/classificação , Vírus/genética , Zoonoses/transmissão , Zoonoses/virologia
4.
PLoS Negl Trop Dis ; 15(9): e0009725, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34516582

RESUMO

Freshwater snails of the genera Biomphalaria, Bulinus, and Oncomelania are intermediate hosts of schistosomes that cause human schistosomiasis, one of the most significant infectious neglected diseases in the world. Identification of freshwater snails is usually based on morphology and potentially DNA-based methods, but these have many drawbacks that hamper their use. MALDI-TOF MS has revolutionised clinical microbiology and has emerged in the medical entomology field. This study aims to evaluate MALDI-TOF MS profiling for the identification of both frozen and ethanol-stored snail species using protein extracts from different body parts. A total of 530 field specimens belonging to nine species (Biomphalaria pfeifferi, Bulinus forskalii, Bulinus senegalensis, Bulinus truncatus, Bulinus globosus, Bellamya unicolor, Cleopatra bulimoides, Lymnaea natalensis, Melanoides tuberculata) and 89 laboratory-reared specimens, including three species (Bi. pfeifferi, Bu. forskalii, Bu. truncatus) were used for this study. For frozen snails, the feet of 127 field and 74 laboratory-reared specimens were used to validate the optimised MALDI-TOF MS protocol. The spectral analysis yielded intra-species reproducibility and inter-species specificity which resulted in the correct identification of all the specimens in blind queries, with log-score values greater than 1.7. In a second step, we demonstrated that MALDI-TOF MS could also be used to identify ethanol-stored snails using proteins extracted from the foot using a specific database including a large number of ethanol preserved specimens. This study shows for the first time that MALDI-TOF MS is a reliable tool for the rapid identification of frozen and ethanol-stored freshwater snails without any malacological expertise.


Assuntos
Esquistossomose/transmissão , Caramujos/classificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Vetores de Doenças/classificação , Água Doce/parasitologia , Senegal , Caramujos/química
5.
Acta Trop ; 220: 105950, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33979639

RESUMO

The occurrence of triatomine species, their bloodmeal sources and the discrete typing units (DTUs) of Trypanosoma cruzi isolated from them were determined in different municipalities of the state of Rio Grande do Norte, Brazil. Triatomine captures were carried out in the rural areas of 23 municipalities. The genotyping of T. cruzi isolates was performed using the mitochondrial cytochrome c oxidase subunit 2 (coii) gene, the D7 region of the 24Sα rDNA, and the spliced leader intergenic region (SL-IR). Five triatomine species were captured, and the most frequent was Triatoma brasiliensis (84.3%; 916/1086), which was found in 16 of the 23 municipalities surveyed, and infested all types of environment investigated. The TcI DTU was found in all mesoregions surveyed in 51.5% (17/33) of the culture-positive samples. In contrast, TcII (9.1%; 3/33) was detected in the Central mesoregion, while TcIII (27.3%; 9/33) was found in all mesoregions. The geographic distribution and spatial overlap of different DTUs was inferred using the superposition of the radius of occurrence of isolates and using ecological niche distribution modelling. Triatoma brasiliensis was found infected in all mesoregions and with all three T. cruzi DTUs, including mixed infections. With regard to bloodmeal sources, the DNA of rodents was found in triatomines infected with either TcI or TcIII, while that of domestic animals and humans was associated with both single and mixed infections. Our findings demonstrate that different DTUs of T. cruzi are widely dispersed among triatomines in our study area. The association of T. brasiliensis with several different mammalian hosts, as well as overlapping areas with different DTUs, suggests that this triatomine species may have an important role as a vector in both anthropic and sylvatic environments.


Assuntos
Triatoma/classificação , Trypanosoma cruzi/classificação , Animais , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/transmissão , DNA Intergênico , Vetores de Doenças/classificação , Secas , Genótipo , Humanos , Triatoma/genética , Triatoma/fisiologia , Trypanosoma cruzi/genética , Trypanosoma cruzi/fisiologia
6.
Crit Rev Microbiol ; 47(3): 307-322, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33570448

RESUMO

The ongoing COVID-19 pandemic has made us wonder what led to its occurrence and what can be done to avoid such events in the future. As we document, one changing circumstance that is resulting in the emergence and changing the expression of viral diseases in both plants and animals is climate change. Of note, the rapidly changing environment and weather conditions such as excessive flooding, droughts, and forest fires have raised concerns about the global ecosystem's security, sustainability, and balance. In this review, we discuss the main consequences of climate change and link these to how they impact the appearance of new viral pathogens, how they may facilitate transmission between usual and novel hosts, and how they may also affect the host's ability to manage the infection. We emphasize how changes in temperature and humidity and other events associated with climate change influence the reservoirs of viral infections, their transmission by insects and other intermediates, their survival outside the host as well the success of infection in plants and animals. We conclude that climate change has mainly detrimental consequences for the emergence, transmission, and outcome of viral infections and plead the case for halting and hopefully reversing this dangerous event.


Assuntos
COVID-19/transmissão , Mudança Climática , Doenças Transmissíveis Emergentes/transmissão , Doenças das Plantas/virologia , Viroses/transmissão , Animais , Organismos Aquáticos/virologia , COVID-19/complicações , COVID-19/etiologia , COVID-19/imunologia , Quirópteros/virologia , Doenças Transmissíveis Emergentes/complicações , Doenças Transmissíveis Emergentes/etiologia , Doenças Transmissíveis Emergentes/imunologia , Produtos Agrícolas/virologia , Reservatórios de Doenças/virologia , Vetores de Doenças/classificação , Abastecimento de Alimentos , Humanos , Umidade , Doenças das Plantas/imunologia , Doenças dos Primatas/transmissão , Doenças dos Primatas/virologia , Primatas , Chuva , Estações do Ano , Temperatura , Viroses/complicações , Viroses/etiologia , Viroses/imunologia
7.
PLoS Biol ; 19(1): e3001066, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33507921

RESUMO

Lyme disease is common in the northeastern United States, but rare in the southeast, even though the tick vector is found in both regions. Infection prevalence of Lyme spirochetes in host-seeking ticks, an important component to the risk of Lyme disease, is also high in the northeast and northern midwest, but declines sharply in the south. As ticks must acquire Lyme spirochetes from infected vertebrate hosts, the role of wildlife species composition on Lyme disease risk has been a topic of lively academic discussion. We compared tick-vertebrate host interactions using standardized sampling methods among 8 sites scattered throughout the eastern US. Geographical trends in diversity of tick hosts are gradual and do not match the sharp decline in prevalence at southern sites, but tick-host associations show a clear shift from mammals in the north to reptiles in the south. Tick infection prevalence declines north to south largely because of high tick infestation of efficient spirochete reservoir hosts (rodents and shrews) in the north but not in the south. Minimal infestation of small mammals in the south results from strong selective attachment to lizards such as skinks (which are inefficient reservoirs for Lyme spirochetes) in the southern states. Selective host choice, along with latitudinal differences in tick host-seeking behavior and variations in tick densities, explains the geographic pattern of Lyme disease in the eastern US.


Assuntos
Vetores de Doenças , Comportamento de Busca por Hospedeiro/fisiologia , Doença de Lyme/epidemiologia , Animais , Animais Selvagens , Borrelia burgdorferi/fisiologia , Clima , Reservatórios de Doenças/microbiologia , Reservatórios de Doenças/estatística & dados numéricos , Vetores de Doenças/classificação , Geografia , Especificidade de Hospedeiro/fisiologia , Humanos , Lagartos/microbiologia , Doença de Lyme/transmissão , Camundongos , Densidade Demográfica , Prevalência , Ratos , Sciuridae/microbiologia , Musaranhos/microbiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/microbiologia , Infestações por Carrapato/transmissão , Carrapatos/microbiologia , Estados Unidos/epidemiologia
8.
J Med Entomol ; 58(2): 830-836, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33047129

RESUMO

Visceral leishmaniasis is spreading in Brazil where the main vector of its agent, Leishmania infantum Nicolle, 1908, is the Lutzomyia longipalpis (Lutz & Neiva, 1912) species complex (Diptera: Psychodidae: Phlebotominae), on which many of the activities of the visceral leishmaniasis surveillance program are based. However, there are areas where canine, and/or human cases have been occurring without the presence of this species complex as in the western part of the Greater São Paulo Metropolitan region, where Embu das Artes municipality is situated. In this area, Pintomyia fischeri (Pinto, 1926) has been implicated as potential vector of Le. infantum but so far its natural infection with this parasite has not yet been ascertained. Therefore, the present study sought to investigate the natural infection in sand flies of a CVL focus in Embu das Artes. The sand fly collections were undertaken with Shannon and CDC traps, monthly, between 1800 and 2100 hours from November 2018 to October 2019, inclusive. A total of 951 sand flies (457 males and 494 females), belonging to 10 species, were captured. Pintomyia fischeri was the predominant species (89.5%); of which 426 females were dissected and one of them (0.23%) was found to be harboring flagellates in its midgut. A sample of these flagellates was isolated in culture and characterized by a 234 base pair fragment of Leishmania heat-shock protein 70 gene (hsp70) and restriction fragment length polymorphism with Hae III restriction enzyme as Le. infantum. This finding reinforces previous evidence of Pi. fischeri as a vector of Le. infantum in foci of visceral leishmaniasis and highlights the importance of vector surveillance in areas where this species occurs.


Assuntos
Leishmania infantum/isolamento & purificação , Leishmaniose Visceral , Psychodidae/parasitologia , Animais , Brasil/epidemiologia , Vetores de Doenças/classificação , Doenças do Cão/prevenção & controle , Doenças do Cão/transmissão , Cães , Monitoramento Epidemiológico , Genes de Protozoários , Proteínas de Choque Térmico HSP72/genética , Humanos , Insetos Vetores/classificação , Insetos Vetores/parasitologia , Leishmania infantum/genética , Leishmaniose Visceral/prevenção & controle , Leishmaniose Visceral/transmissão , Psychodidae/classificação , Doenças Transmitidas por Vetores/prevenção & controle , Doenças Transmitidas por Vetores/transmissão , Doenças Transmitidas por Vetores/veterinária , Zoonoses/prevenção & controle , Zoonoses/transmissão
9.
Infect Genet Evol ; 87: 104670, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33301987

RESUMO

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causing agent of Coronavirus Disease-2019 (COVID-19), is likely to be originated from bat and transmitted through intermediate hosts. However, the immediate source species of SARS-CoV-2 have not yet been confirmed. Here, we used diversity analysis of the angiotensin I converting enzyme 2 (ACE2) that serves as cellular receptor for SARS-CoV-2 and transmembrane protease serine 2 (TMPRSS2), which has been proved to be utilized by SARS-CoV-2 for spike protein priming. We also simulated the structure of receptor-binding domain of SARS-CoV-2 spike protein (SARS-CoV-2S RBD) with the ACE2s to investigate their binding affinity to determine the potential intermediate animal hosts that could spread the SARS-CoV-2 to humans in South Asia. We identified cow, buffalo, goat and sheep, which are predominant species in the household farming system in South Asia that can potentially be infected by SARS-CoV-2. All the bird species studied along with rat and mouse were considered less potential to interact with SARS-CoV-2. The interaction interfaces of SARS-CoV-2S RBD and ACE2 protein complex suggests pangolin as a potential intermediate host in SARS-CoV-2. Our results provide a valuable resource for the identification of potential hosts for SARS-CoV-2 in South Asia and henceforth reduce the opportunity for a future outbreak of COVID-19.


Assuntos
COVID-19/transmissão , Vetores de Doenças/classificação , Enzima de Conversão de Angiotensina 2/genética , Animais , Ásia/epidemiologia , COVID-19/epidemiologia , COVID-19/virologia , Humanos , Filogenia , SARS-CoV-2/isolamento & purificação , Serina Endopeptidases/genética , Especificidade da Espécie
10.
Epidemiol. serv. saúde ; 30(2): e2020154, 2021. graf
Artigo em Inglês, Português | LILACS | ID: biblio-1249796

RESUMO

Objetivo: Comparar o mapeamento oficial com um mapeamento probabilístico da infestação por Aedes spp. nos municípios do Rio Grande do Sul, Brasil. Métodos: Estudo ecológico com dados de amostras de criadouros em 2016-2017; obteve-se a classificação oficial em boletins epidemiológicos e estimou-se a probabilidade de infestação por município e semana, ajustando-se um modelo dinâmico de ocupação de sítios aos dados da vigilância epidemiológica municipal. Resultados: 187.245 amostras coletadas em 473 municípios originaram 10.648 detecções de Aedes aegypti e 8.414 de Aedes albopictus; o mapeamento oficial concorda com o probabilístico em municípios da região noroeste e oeste do RS; os mapeamentos discordam nas regiões leste, centro, nordeste e sul, revelando municípios oficialmente não infestados com alta probabilidade de infestação e notificação de arboviroses. Conclusão: A classificação oficial identificou infestação nos municípios infestados do noroeste e oeste, e não identificou infestação em municípios com possíveis falsos zeros e onde ela varia temporalmente.


Objetivo: Comparar el mapeo oficial con un mapeo probabilístico de infestación por Aedes spp. en los municipios de Rio Grande do Sul, Brasil. Métodos: Estudio ecológico analizando muestras colectadas en criaderos en 2016-2017; se obtuvo la clasificación oficial en boletines epidemiológicos, y la probabilidad de infestación por municipio y semana ajustando un modelo dinámico de ocupación de sitios a los datos de la vigilancia epidemiológica municipal. Resultados: 187.245 muestras de 473 municipios generaron 10.648 detecciones de Aedes aegypti y 8.414 detecciones de Aedes albopictus. El mapeo oficial está de acuerdo con el probabilístico en municipios del noroeste y oeste de RS; los mapeos no concuerdan en el este, centro, nordeste y sur, revelando municipios oficialmente no infestados con alta probabilidad de infestación y notificación de arbovirus. Conclusión: Mientras la clasificación oficial identifica municipios del noroeste y oeste infestados críticamente, no identifica infestación en municipios con posiblemente falsos ceros y en donde la infestación varía temporalmente.


Objective: To compare official mapping with probabilistic mapping of infestation by Aedes spp. in the municipalities of Rio Grande do Sul state, Brazil. Methods: This was an ecological study using data from samples of mosquito breeding sites collected in 2016-2017; official classification was obtained from epidemiological reports, and infestation per municipality and week was estimated by fitting a dynamic site-occupancy model to data from municipal epidemiological surveillance. Results: 187,245 samples collected in 473 municipalities returned 10,648 detections of Aedes aegypti, and 8,414 detections of Aedes albopictus; official mapping agrees with probabilistic mapping in municipalities in the northwestern and western regions of the state. The mappings are not in agreement in the eastern, central, northeastern and southern regions, revealing municipalities officially not infested but with high probability of infestation and notification of arbovirus infection. Conclusion: While official classification identified critically infested municipalities in the state's northwestern and western regions, it did not identify infestation in municipalities with possible false zero errors and where infestation varies over time.


Assuntos
Humanos , Animais , Aedes/virologia , Vetores de Doenças/classificação , Monitoramento Epidemiológico , Infecções por Arbovirus/prevenção & controle , Brasil/epidemiologia , Probabilidade , Controle de Vetores de Doenças , Modelos Teóricos
11.
PLoS Negl Trop Dis ; 14(10): e0008849, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33108372

RESUMO

Matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry is an analytical method that detects macromolecules that can be used for proteomic fingerprinting and taxonomic identification in arthropods. The conventional MALDI approach uses fresh laboratory-reared arthropod specimens to build a reference mass spectra library with high-quality standards required to achieve reliable identification. However, this may not be possible to accomplish in some arthropod groups that are difficult to rear under laboratory conditions, or for which only alcohol preserved samples are available. Here, we generated MALDI mass spectra of highly abundant proteins from the legs of 18 Neotropical species of adult field-collected hard ticks, several of which had not been analyzed by mass spectrometry before. We then used their mass spectra as fingerprints to identify each tick species by applying machine learning and pattern recognition algorithms that combined unsupervised and supervised clustering approaches. Both Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) classification algorithms were able to identify spectra from different tick species, with LDA achieving the best performance when applied to field-collected specimens that did have an existing entry in a reference library of arthropod protein spectra. These findings contribute to the growing literature that ascertains mass spectrometry as a rapid and effective method to complement other well-established techniques for taxonomic identification of disease vectors, which is the first step to predict and manage arthropod-borne pathogens.


Assuntos
Ixodidae/química , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/metabolismo , Vetores de Doenças/classificação , Ixodidae/classificação , Ixodidae/metabolismo
12.
Parasit Vectors ; 13(1): 332, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32611375

RESUMO

BACKGROUND: Triatoma dimidiata (Reduviidae: Triatominae) is an important vector of Chagas disease in various countries in the Americas. Phylogenetic studies have defined three lineages in Mexico and part of Central America. While there is a marked genetic differentiation, methods for identifying them using morphometric analyses with landmarks have not yet been fully resolutive. Elliptical Fourier descriptors (EFDs), which mathematically describe the shape of any closed two-dimensional contours, could be a potentially useful alternative method. Our objective was to validate the use of EFDs for the identification of three lineages of this species complex. METHOD: A total of 84 dorsal view images of individuals of the three lineages were used. Body contours were described with EFDs using between 5 and 30 harmonics. The number of obtained coefficients was reduced by a principal components analysis and the first axis scores were used as shape variables. A linear discriminant function analysis and an ordination plot of the discriminant analysis were performed using the shape variables. A confusion matrix of the ordination plot of the discriminant analysis was obtained to estimate the classification errors, the first five PC scores were statistically compared, and a neural network were then performed using the shape variables. RESULTS: The first principal component explained 50% of the variability, regardless the number of harmonics used. The results of discriminant analysis get improved by increasing the number of harmonics and components considered. With 25 harmonics and 30 components, the identification of haplogroups was achieved with an overall efficiency greater than 97%. The ordering diagram showed the correct discrimination of haplogroups, with only one error of discrimination corroborated by the confusion matrix. When comparing the first five PC scores, significant differences were found among at least two haplogroups. The 30 multilayer perceptron neural networks were also efficient in identification, reaching 91% efficiency with the validation data. CONCLUSIONS: The use of EFD is a simple and useful method for the identification of the main lineages of Triatoma dimidiata, with high values of correct identification.


Assuntos
Classificação/métodos , Triatoma , Animais , Doença de Chagas/transmissão , Vetores de Doenças/classificação , Insetos Vetores/anatomia & histologia , Insetos Vetores/classificação , México , Triatoma/anatomia & histologia , Triatoma/classificação
13.
Parasit Vectors ; 13(1): 333, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32611432

RESUMO

BACKGROUND: Anopheles mosquitoes are the vectors of malaria, one of the most important infectious diseases in the tropics. More than 500 Anopheles species have been described worldwide, and more than 30 are considered a public health problem. In Honduras, information on the distribution of Anopheles spp. and its genetic diversity is scarce. This study aimed to describe the distribution and genetic diversity of Anopheles mosquitoes in Honduras. METHODS: Mosquitoes were captured in 8 locations in 5 malaria endemic departments during 2019. Two collection methods were used. Adult anophelines were captured outdoors using CDC light traps and by aspiration of mosquitoes at rest. Morphological identification was performed using taxonomic keys. Genetic analyses included the sequencing of a partial region of the cytochrome c oxidase 1 gene (cox1) and the ribosomal internal transcribed spacer 2 (ITS2). RESULTS: A total of 1320 anophelines were collected and identified through morphological keys. Seven Anopheles species were identified. Anopheles albimanus was the most widespread and abundant species (74.02%). To confirm the morphological identification of the specimens, 175 and 122 sequences were obtained for cox1 and ITS2, respectively. Both markers confirmed the morphological identification. cox1 showed a greater nucleotide diversity than ITS2 in all species. High genetic diversity was observed within the populations of An. albimanus while An. darlingi proved to be a highly homogeneous population. Phylogenetic analyses revealed clustering patterns in An. darlingi and An. neivai in relation to specimens from South America. New sequences for An. crucians, An. vestitipennis and An. neivai are reported in this study. CONCLUSIONS: Here we report the distribution and genetic diversity of Anopheles species in endemic areas of malaria transmission in Honduras. According to our results, both taxonomic and molecular approaches are useful tools in the identification of anopheline mosquitoes. However, both molecular markers differ in their ability to detect intraspecific genetic diversity. These results provide supporting data for a better understanding of the distribution of malaria vectors in Honduras.


Assuntos
Anopheles , Mosquitos Vetores , Animais , Anopheles/classificação , Anopheles/genética , Classificação/métodos , DNA Espaçador Ribossômico/genética , Vetores de Doenças/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes de Insetos , Marcadores Genéticos , Variação Genética , Honduras/epidemiologia , Malária/transmissão , Mosquitos Vetores/classificação , Mosquitos Vetores/genética , Filogenia
14.
PLoS One ; 15(5): e0232616, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32379806

RESUMO

Bemisia tabaci (sensu latu) is a group of >40 highly cryptic whitefly species that are of global agricultural importance, both as crop pests and plant-virus vectors. Two devastating cassava diseases in East and Central Africa are spread by abundant populations of one of these species termed Sub-Saharan Africa 1 (SSA1). There is a substantive risk that these whitefly-borne pandemics will continue to spread westwards and disrupt cassava production for millions of smallholder farmers in West Africa. We report here, therefore, the first comprehensive survey of cassava B. tabaci in eastern Nigeria, a West African region likely to be the first affected by the arrival of these whitefly-borne pandemics. We found one haplotype comprising 32 individuals with 100% identical mtCO1 sequence to the East African SSA1 populations (previously termed SSA1-SG1) and 19 mtCO1 haplotypes of Sub-Saharan Africa 3 (SSA3), the latter being the most prevalent and widely distributed B. tabaci species in eastern Nigeria. A more divergent SSA1 mtCO1 sequence (previously termed SSA1-SG5) was also identified in the region, as were mtCO1 sequences identifying the presence of the MED ASL B. tabaci species and Bemisia afer. Although B. tabaci SSA1 was found in eastern Nigeria, they were not present in the high abundances associated with the cassava mosaic (CMD) and cassava brown streak disease (CBSD) pandemics of East and Central Africa. Also, no severe CMD or any CBSD symptoms were found in the region.


Assuntos
Vetores de Doenças/classificação , Hemípteros/classificação , Doenças das Plantas , Animais , Haplótipos , Hemípteros/genética , Hemípteros/patogenicidade , Manihot/crescimento & desenvolvimento , Nigéria , Filogenia
15.
Vet Parasitol Reg Stud Reports ; 20: 100408, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32448524

RESUMO

The Lymnaeidae constitute a family of freshwater gastropod molluscs whose diversity and ecology have been infrequently studied throughout Colombia. Some lymnaeid species act as intermediate hosts of trematode parasites, which are of great importance in both the veterinary and medical fields. Among trematode parasites, Fasciola hepatica is best known for being an important parasite of sheep and cattle for decades and causes significant economic losses in these livestock species. The main objective of this work is to identify the various species of lymnaeids that occupy different geographical regions of Santander and its bordering departments within Colombia. This will expand the knowledge of lymnaeid diversity in Colombia and provide further insight into their role in the transmission of F. hepatica. A total of 118 georeferenced sites between 126 m.a.s.l. and 3870 m.a.s.l. were sampled in Santander, Boyacá, Norte de Santander and Cundinamarca, respectively. Lymnaeid snails were identified according to the morphology of their shells and by several characteristics of their reproductive systems. Species identification was confirmed using DNA barcoding. Four lymnaeid species are reported in the study area: the native Galba cousini and three exotic species, Pseudosuccinea columella, G. truncatula and G. schirazensis. The four species were examined for natural infection with F. hepatica. Infected variants of the main snail host, G. cousini, were found in the Onzaga, Encino and Vetas municipalities of Santander, as well as in the Belén municipality of Boyacá. A second species, G. truncatula was also found naturally infected in Mutiscua municipality of Norte de Santander. The two other species, P. columella and G. schirazensis were found free of infection.


Assuntos
Caramujos/classificação , Animais , Colômbia , Vetores de Doenças/classificação , Fasciola hepatica , Caramujos/anatomia & histologia , Caramujos/genética , Caramujos/parasitologia
16.
BMC Genomics ; 21(1): 170, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070289

RESUMO

BACKGROUND: To date, four thrips vectors have been reported to transmit five different tospoviruses in India. Their identification at an early stage is crucial in formulating appropriate pest management strategies. Since morphometric key-based thrips identification based on the adult stage is time-consuming, there is a need to develop diagnostic tools which are rapid, accurate, and independent of developmental stages. Here, we report a multiplex PCR assay to identify four major thrips vectors viz. Thrips palmi, T. tabaci, Scirtothrips dorsalis, and Frankliniella schultzei present in India. RESULTS: Cytochrome oxidase subunit III and internal transcribed spacer region 2 were utilized to design species-specific primers. Of 38 pairs of primers tested, primer pairs AG35F-AG36R, AG47F-AG48R, AG87F-AG88R, and AG79F-AG80R amplified 568 bp, 713 bp, 388 bp, and 200 bp products from the DNA templates of T. palmi, S. dorsalis, T. tabaci, and F. schultzei, respectively at same PCR conditions. The specificity of the primer pairs was validated with a large number of known specimens and no cross-reactivity was observed with other thrips species. The multiplex PCR assay with a cocktail of all the four primer pairs detected four thrips vectors efficiently and could discriminate all of them concurrently in a single reaction. CONCLUSION: The multiplex PCR reported in this study could identify the major thrips vectors reported in India. The assay will be useful in ascertaining distribution profile of major thrips vectors, disease epidemiology, screening large samples, and quarantine.


Assuntos
Vetores de Doenças/classificação , Reação em Cadeia da Polimerase Multiplex , Tisanópteros/classificação , Tisanópteros/genética , Tospovirus , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Índia , Reprodutibilidade dos Testes , Tisanópteros/virologia
17.
PLoS One ; 15(1): e0227678, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31940405

RESUMO

BACKGROUND: As globalization and climate change progress, the expansion and introduction of vector-borne diseases (VBD) from endemic regions to non-endemic regions is expected to occur. Mathematical and statistical models can be useful in predicting when and where these changes in distribution may happen. Our objective was to conduct a scoping review to identify and characterize predictive and importation models related to vector-borne diseases that exist in the global literature. METHODS: A literature search was conducted to identify publications published between 1999 and 2016 from five scientific databases using relevant keywords. All publications had to be in English or French, and include a predictive or importation model on VBDs, pathogens, reservoirs and/or vectors. Relevance screening and data characterization were performed by two reviewers using pretested forms. The data were analyzed using descriptive statistics. RESULTS: The search initially identified 19 710 unique articles, reports, and conference abstracts. This was reduced to 428 relevant documents after relevance screening and data charting. About half of the models used mathematical techniques, and the remainder were statistical. Most of the models were predictive (87%), rather than importation (5%). The most commonly investigated diseases were malaria and dengue fever. Around 12% of the publications did not report all the parameters used in their model. Only 29% of the models incorporated the impacts of climate change. CONCLUSIONS: A wide variety of mathematical and statistical models on vector-borne diseases exist. Researchers creating their own mathematical and/or statistical models may be able to use this scoping review to be informed about the diseases and/or regions, parameters, model types, and methodologies used in published models.


Assuntos
Vetores de Doenças/classificação , Previsões/métodos , Doenças Transmitidas por Vetores/classificação , Animais , Dengue/epidemiologia , Humanos , Insetos Vetores , Malária/epidemiologia , Modelos Estatísticos , Modelos Teóricos
18.
Acta Trop ; 201: 105220, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31618609

RESUMO

Mexico has great diversity of phlebotomine sand flies related to cases of leishmaniasis, yet few studies have dressed the molecular taxonomy of these sand fly species. The use of the cytochrome oxidase subunit 1 (COI) gene, as a DNA Barcode has facilitated the molecular identification of sand flies species worldwide. We use the DNA barcode as a useful tool for the identification of phlebotomine sand flies of the natural reserve Los Tuxtlas from Veracruz, México. A fragment of 536 bp of the COI gene was obtained from 36 individuals belonging to eight species of five genera (Dampfomyia, Lutzomyia, Psathyromyia, Psychodopygus and Brumptomyia) with coverage between 92-100%, and found similarities ranging from 93-98% with other New World phlebotomine sand flies. The NJ dendogram grouped sand flies into eight clusters according to identified species, supported by bootstrap of 97%-100%. In conclusion, all phlebotomine sand flies were correctly identified and agree with the morphological identification, also could separate genetics the isomorphic females of the genus Brumptomyia.


Assuntos
Código de Barras de DNA Taxonômico , Vetores de Doenças/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Leishmaniose/genética , Phlebotomus/classificação , Phlebotomus/genética , Animais , Brasil , Feminino , México
19.
Rev. cuba. med. trop ; 71(3): e386, sept.-dic. 2019. tab
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1093579

RESUMO

Introducción: A nivel mundial, Aedes aegypti es el culícido más importante en cuanto a la transmisión de arbovirus de impacto en salud pública. Objetivo: Profundizar en los conocimientos ecológicos de Ae. aegypti en República Dominicana, a través de los recipientes o contenedores que utiliza para desarrollar sus formas preimaginales. Métodos: El estudio se extendió desde octubre a diciembre de 2017. Se muestrearon aleatoriamente 100 viviendas, en las que se revisaron todos los recipientes con potencialidad para albergar larvas y/o pupas de mosquitos, dentro y fuera del domicilio. Se cuantificó el tipo y total de cada depósito positivo según su ubicación en cada vivienda, para calcular el porcentaje de representatividad, junto al Índice Pupal por Depósitos específicos (IPDe) para cada receptáculo con pupas. Resultados: Se detectó presencia de Ae. aegypti en el 41 por ciento de las casas visitadas. De los 419 recipientes analizados, 74 resultaron positivos a larvas y/o pupas (17,66 por ciento). Se clasificaron 28 tipos de depósitos atendiendo a su función y material. Cuantitativamente, los depósitos permanentes fueron los más representativos con un 54,05 por ciento. Las mayores capturas se realizaron en el peridomicilio. El tanque plástico fue el más relevante, pues aportó el 28,37 por ciento del total de depósitos positivos, así como un elevado IPDe. Conclusiones: Los resultados evidencian elevados niveles de infestación en los domicilios de Jarabacoa que deben ser controlados a fin de disminuir el riesgo en la transmisión de arbovirosis. El control de los recipientes artificiales, como los contenedores desechables, los neumáticos y sobre todo los tanques de agua, es la piedra angular de cualquier esfuerzo para prevenir estas enfermedades(AU)


Introduction: Aedes aegypti is the most important culicid worldwide in terms of transmission of arbovirus infections of a high impact on public health. Objective: Broaden ecological knowledge about Aedes aegypti in the Dominican Republic, particularly about the containers and other sites where immature development occurs. Methods: The study extended from October to December 2017. One hundred households were randomly surveyed, checking all the containers with a potential to host mosquito larvae and/or pupae both inside and outside the house. Quantification was made of the type and total of positive containers according to their location in each household, to estimate the percentage of representativeness and the pupal index per container identified (PICI) when pupae were found in them. Results: Aedes aegypti was found to be present in 41 percent of the houses visited. Of the 419 containers analyzed, 74 were positive for larvae and/or pupae (17.66 percent). Containers were classified into 28 types according to their function and material. Quantitatively, permanent containers were the best represented with 54.05 percent. The largest captures were made in the area around the house. Plastic water tanks were the most relevant, with 28.37 percent of the total positive containers and a high PICI. Conclusions: Results show high levels of infestation in Jarabacoa households. These should be controlled to reduce the risk of arbovirus infection transmission. Control of artificial breeding sites, such as disposable containers, tires and especially water tanks, is the cornerstone of any effort to prevent these diseases(AU)


Assuntos
Humanos , Masculino , Feminino , Ecossistema , Aedes/microbiologia , Vetores de Doenças/classificação , Larva/crescimento & desenvolvimento
20.
Viruses ; 11(11)2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31683823

RESUMO

We reviewed the literature on the role of temperature in transmission of zoonotic arboviruses. Vector competence is affected by both direct and indirect effects of temperature, and generally increases with increasing temperature, but results may vary by vector species, population, and viral strain. Temperature additionally has a significant influence on life history traits of vectors at both immature and adult life stages, and for important behaviors such as blood-feeding and mating. Similar to vector competence, temperature effects on life history traits can vary by species and population. Vector, host, and viral distributions are all affected by temperature, and are generally expected to change with increased temperatures predicted under climate change. Arboviruses are generally expected to shift poleward and to higher elevations under climate change, yet significant variability on fine geographic scales is likely. Temperature effects are generally unimodal, with increases in abundance up to an optimum, and then decreases at high temperatures. Improved vector distribution information could facilitate future distribution modeling. A wide variety of approaches have been used to model viral distributions, although most research has focused on the West Nile virus. Direct temperature effects are frequently observed, as are indirect effects, such as through droughts, where temperature interacts with rainfall. Thermal biology approaches hold much promise for syntheses across viruses, vectors, and hosts, yet future studies must consider the specificity of interactions and the dynamic nature of evolving biological systems.


Assuntos
Arbovírus/fisiologia , Vetores de Doenças , Temperatura , Doenças Transmitidas por Vetores/transmissão , Animais , Arbovírus/classificação , Mudança Climática , Vetores de Doenças/classificação , Ecossistema , Mosquitos Vetores/fisiologia , Mosquitos Vetores/virologia , Especificidade da Espécie , Vírus do Nilo Ocidental/fisiologia
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