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1.
Med Vet Entomol ; 38(2): 216-226, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38563591

RESUMO

Vector control remains one of the best strategies to prevent the transmission of trypanosome infections in humans and livestock and, thus, a good way to achieve the elimination of human African trypanosomiasis and animal African trypanosomiasis. A key prerequisite for the success of any vector control strategy is the accurate identification and correct mapping of tsetse species. In this work, we updated the tsetse fly species identification and distribution in many geographical areas in Cameroon. Tsetse flies were captured from six localities in Cameroon, and their species were morphologically identified. Thereafter, DNA was extracted from legs of each tsetse fly and the length polymorphism of internal transcribed spacer-1 (ITS1) region of each fly was investigated using PCR. ITS1 DNA fragments of each tsetse species were sequenced. The sequences obtained were analysed and compared to those available in GenBank. This enabled to confirm/infirm results of the morphologic identification and then, to establish the phylogenetic relationships between tsetse species. Morphologic features allowed to clearly distinguish all the tsetse species captured in the South Region of Cameroon, that is, Glossina palpalis palpalis, G. pallicera, G. caliginea and G. nigrofusca. In the northern area, G. morsitans submorsitans could also be distinguished from G. palpalis palpalis, G. tachinoides and G. fuscipes, but these three later could not be distinguished with routine morphological characters. The ITS1 length polymorphism was high among most of the studied species and allowed to identify the following similar species with a single PCR, that is, G. palpalis palpalis with 241 or 242 bp and G. tachinoides with 221 or 222 bp, G. fuscipes with 236 or 237 bp. We also updated the old distribution of tsetse species in the areas assessed, highlighting the presence of G. palpalis palpalis instead of G. fuscipes in Mbakaou, or in sympatry with G. morsitans submorsitans in Dodeo (northern Cameroon). This study confirms the presence of G. palpalis palpalis in the Adamawa Region of Cameroon. It highlights the limits of using morphological criteria to differentiate some tsetse species. Molecular tools based on the polymorphism of ITS1 of tsetse flies can differentiate tsetse species through a simple PCR before downstream analyses or vector control planning.


Assuntos
Insetos Vetores , Polimorfismo Genético , Moscas Tsé-Tsé , Animais , Camarões , Moscas Tsé-Tsé/genética , Insetos Vetores/genética , Insetos Vetores/classificação , Distribuição Animal , Filogenia , DNA Intergênico/genética , Feminino , Controle de Insetos , Masculino , DNA Espaçador Ribossômico/análise , DNA Espaçador Ribossômico/genética , Análise de Sequência de DNA
2.
Mem Inst Oswaldo Cruz ; 119: e230226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38865577

RESUMO

BACKGROUND: Monitoring and analysing the infection rates of the vector of Trypanosoma cruzi, that causes Chagas disease, helps assess the risk of transmission. OBJECTIVES: A study was carried out on triatomine in the State of Paraná, Brazil, between 2012 and 2021 and a comparison was made with a previous study. This was done to assess the risk of disease transmission. METHODS: Ecological niche models based on climate and landscape variables were developed to predict habitat suitability for the vectors as a proxy for risk of occurrence. FINDINGS: A total of 1,750 specimens of triatomines were recorded, of which six species were identified. The overall infection rate was 22.7%. The areas with the highest risk transmission of T. cruzi are consistent with previous predictions in municipalities. New data shows that climate models are more accurate than landscape models. This is likely because climate suitability was higher in the previous period. MAIN CONCLUSION: Regardless of uneven sampling and potential biases, risk remains high due to the wide presence of infected vectors and high environmental suitability for vector species throughout the state and, therefore, improvements in public policies aimed at wide dissemination of knowledge about the disease are recommended to ensure the State remains free of Chagas disease.


Assuntos
Doença de Chagas , Insetos Vetores , Triatominae , Trypanosoma cruzi , Doença de Chagas/transmissão , Animais , Insetos Vetores/classificação , Insetos Vetores/parasitologia , Brasil/epidemiologia , Triatominae/classificação , Triatominae/parasitologia , Humanos , Fatores de Risco , Medição de Risco , Ecossistema
3.
An Acad Bras Cienc ; 96(2): e20230872, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747792

RESUMO

Aiming to compare and update the sand fly fauna of Portão de Pedra site, Sumidouro District, Rio de Janeiro State, Brazil, and considering the environmental changes occurred, the biology and ecology of the local sandfly species were examined five years later as a complementary study carried. Captures were made in the cave, surroundings of cave and forest of the region, from 6 p.m. to 6 a.m. Among the 2323 sandflies of eigth species of the Lutzomyia were captured: L. gasparviannai, L. edwardsi, L. tupynambai, L. hirsuta, L. whitmani, L. migonei, L. intermedia, Lutzomyia. sp and one species of the Brumptomyia Kind: B. brumpti. In 2009 and 2010 were collected 1756 samples from ten species of the former genus and two of the second. L. gasparviannai was predominant, in the three collection sites, in both periods. Five species implicated as vectors of Leishmania: L. intermedia, L. whitmani, L. migonei, L. hirsuta and L. davisi have been collected in the area. Poisson regression and ANOVA were used to perform statistical analysis of species most relevant. The record of L. intermedia and a case of American tegumentary leishmaniasis are relevant to the public health of municipality and of state of Rio de Janeiro.


Assuntos
Insetos Vetores , Psychodidae , Animais , Psychodidae/classificação , Brasil , Insetos Vetores/classificação , Densidade Demográfica , Feminino , Masculino , Estações do Ano , Ecossistema
4.
J Vector Borne Dis ; 61(2): 236-242, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38922658

RESUMO

BACKGROUND OBJECTIVES: Sandflies are vector insects associated with terrestrial forest ecosystems; in the Ecuadorian Andes, they participate in the transmission of human cutaneous leishmaniasis. This geographical area represents an opportunity to evaluate the role of sandflies as bioindicators of the degree of intervention of tropical humid forest ecosystems (THF) associated with changes in the ecology of the local landscape. METHODS: CDC-light traps were used for collecting adult sandflies in February 2020 in a humid tropical forest within the Chocó Biosphere Reserve. All species were identified using morphological keys. Analysis data about abundance, richness, species accumulation, diversity index, species composition communities, species sex proportion, spatial sandflies environmental, Renyi's Diversity Profile were performed to compare six spatial habitats in Mashpi locality, Ecuador. RESULTS: Sandflies were collected (n-1435); the main species are represented by Trichophoromyia reburra, Nyssomyia trapidoi, Psathyromyia aclydifera, Psychodopygus panamensis and Lutzomyia hartmanni. Only Th. reburra is associated with not intervened forest, while the other three species are associated with intervened forest within Mashpi in the Choco Biosphere Reserve. The secondary forest has major sandflies' richness, while the primary forest exhibits major abundance. INTERPRETATION CONCLUSION: Th. reburra is a sandfly restricted to the Andean Forest and is a bioindicator of the high environmental health quality of the forest, while Ny. trapidoi and Pa. aclydifera are bioindicators of environmental disturbances in the forest. Additionally, Ps. panamensis, Lu. hartmanni and Ny. trapidoi are bioindicators of human impact and the risk of leishmaniasis.


Assuntos
Ecossistema , Florestas , Insetos Vetores , Psychodidae , Animais , Psychodidae/fisiologia , Psychodidae/classificação , Insetos Vetores/fisiologia , Insetos Vetores/classificação , Equador , Masculino , Feminino , Leishmaniose Cutânea/transmissão , Biodiversidade , Humanos
5.
Arch Microbiol ; 203(5): 1891-1915, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33634321

RESUMO

Insects and bacteria are the most widespread groups of organisms found in nearly all habitats on earth, establishing diverse interactions that encompass the entire range of possible symbiotic associations from strict parasitism to obligate mutualism. The complexity of their interactions is instrumental in shaping the roles of insects in the environment, meanwhile ensuring the survival and persistence of the associated bacteria. This review aims to provide detailed insight on the multifaceted symbiosis between one of the most versatile bacterial genera, Pseudomonas (Gammaproteobacteria: Pseudomonadaceae) and a diverse group of insect species. The Pseudomonas engages with varied interactions with insects, being either a pathogen or beneficial endosymbiont, as well as using insects as vectors. In addition, this review also provides updates on existing and potential applications of Pseudomonas and their numerous insecticidal metabolites as biocontrol agents against pest insects for the improvement of integrated pest management strategies. Here, we have summarized several known modes of action and the virulence factors of entomopathogenic Pseudomonas strains essential for their pathogenicity against insects. Meanwhile, the beneficial interactions between pseudomonads and insects are currently limited to a few known insect taxa, despite numerous studies reporting identification of pseudomonads in the guts and haemocoel of various insect species. The vector-symbiont association between pseudomonads and insects can be diverse from strict phoresy to a role switch from commensalism to parasitism following a dose-dependent response. Overall, the pseudomonads appeared to have evolved independently to be either exclusively pathogenic or beneficial towards insects.


Assuntos
Insetos/microbiologia , Pseudomonas/fisiologia , Animais , Agentes de Controle Biológico , Interações Hospedeiro-Patógeno , Insetos Vetores/classificação , Insetos Vetores/microbiologia , Insetos/classificação , Pseudomonas/metabolismo , Simbiose , Fatores de Virulência/metabolismo
6.
Int Microbiol ; 24(2): 141-147, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33156443

RESUMO

Direct test over the gut material from triatomine vectors and xenodiagnosis over mammalian hosts are classical techniques for Trypanosoma cruzi parasitological diagnosis. Nevertheless, negative results can be a source of uncertainty. Experimental models have allowed evaluating the tissue invasion of different strains of T. cruzi, but conventional techniques for tissue biopsies involve time-consuming and elaborated procedures and have low sensitivity. Gut material of collected triatomines (microscopically negative) (n = 114), material of mammal xenodiagnoses (microscopically negative) (n = 138), and biopsy material (microscopically negative) from experimentally infected animals (n = 34) with isolates from endemic areas of Chagas' disease from Venezuela were used for DNA extraction and PCR for the amplification of kinetoplast DNA (kDNA) and satellite DNA (sDNA) of T. cruzi. Positive PCR was observed in 53.6% of collected triatomine material, 15.8% of parasitological negative xenodiagnosis material, and 70.6% in biopsies, revealing underestimation by the parasitological tests and the valour of this analysis with preserved material. Anzoátegui was the state with the highest percentage of infection, and the triatomine species Rhodnius prolixus and Panstrongylus geniculatus had the highest percentages of infection. Didelphis marsupialis and Canis familiaris were the most infected by T. cruzi revealed by PCR of xenodiagnosis material. In addition, the PCR technique allowed demonstrating the invasion of T. cruzi in all tissues analyzed, constituting a molecular marker of tissue invasion.


Assuntos
Doença de Chagas/parasitologia , DNA de Protozoário/genética , Didelphis/parasitologia , Insetos Vetores/parasitologia , Triatominae/parasitologia , Trypanosoma cruzi/genética , Animais , Biópsia , Doença de Chagas/diagnóstico , Cães , Humanos , Insetos Vetores/classificação , Reação em Cadeia da Polimerase , Triatominae/classificação , Trypanosoma cruzi/isolamento & purificação , Xenodiagnóstico
7.
Parasitol Res ; 120(7): 2323-2332, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33893548

RESUMO

Culicoides biting midges are small dipterous insects (Diptera: Ceratopogonidae) which are known to be vectors of arboviruses, bacteria, protozoan and helminth parasites that can cause disease and mortality in livestock and poultry globally. Detailed knowledge of the Culicoides species composition and biology is essential to assess the risk of the introduction and transmission of pathogens. The aim of this study was to obtain data on Culicoides species composition and flying activity in southeastern Lithuania and to determine the meteorological variables related to the abundance of Culicoides biting midges. Biting midges were collected in Verkiai Regional Park, southeastern Lithuania, using an Onderstepoort trap once a week from April to October 2016 and 2018, and from April to July 2019; 7332 Culicoides females belonging to 22 species were identified. Both morphology and DNA barcoding were used for identification. The number of specimens trapped was highest for the Obsoletus Group, followed by Culicoides kibunensis and Culicoides impunctatus. The highest relative abundance and diversity of biting midges were found in May and June. The number of trapped biting midges correlated positively with the mean air temperature. The first biting midges in spring were caught when the mean daily temperature rose higher than 10 °C. No Culicoides were detected when the air temperature dropped below 5 °C in autumn. Wind speed and air humidity had no statistically significant effect on Culicoides abundance.


Assuntos
Ceratopogonidae/fisiologia , Voo Animal/fisiologia , Insetos Vetores/fisiologia , Animais , Ceratopogonidae/classificação , Análise por Conglomerados , Feminino , Insetos Vetores/classificação , Lituânia , Estações do Ano , Temperatura
8.
J Virol ; 93(21)2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31413126

RESUMO

The plant-pathogenic virus tomato spotted wilt virus (TSWV) encodes a structural glycoprotein (GN) that, like with other bunyavirus/vector interactions, serves a role in viral attachment and possibly in entry into arthropod vector host cells. It is well documented that Frankliniella occidentalis is one of nine competent thrips vectors of TSWV transmission to plant hosts. However, the insect molecules that interact with viral proteins, such as GN, during infection and dissemination in thrips vector tissues are unknown. The goals of this project were to identify TSWV-interacting proteins (TIPs) that interact directly with TSWV GN and to localize the expression of these proteins in relation to virus in thrips tissues of principal importance along the route of dissemination. We report here the identification of six TIPs from first-instar larvae (L1), the most acquisition-efficient developmental stage of the thrips vector. Sequence analyses of these TIPs revealed homology to proteins associated with the infection cycle of other vector-borne viruses. Immunolocalization of the TIPs in L1 revealed robust expression in the midgut and salivary glands of F. occidentalis, the tissues most important during virus infection, replication, and plant inoculation. The TIPs and GN interactions were validated using protein-protein interaction assays. Two of the thrips proteins, endocuticle structural glycoprotein and cyclophilin, were found to be consistent interactors with GN These newly discovered thrips protein-GN interactions are important for a better understanding of the transmission mechanism of persistent propagative plant viruses by their vectors, as well as for developing new strategies of insect pest management and virus resistance in plants.IMPORTANCE Thrips-transmitted viruses cause devastating losses to numerous food crops worldwide. For negative-sense RNA viruses that infect plants, the arthropod serves as a host as well by supporting virus replication in specific tissues and organs of the vector. The goal of this work was to identify thrips proteins that bind directly to the viral attachment protein and thus may play a role in the infection cycle in the insect. Using the model plant bunyavirus tomato spotted wilt virus (TSWV), and the most efficient thrips vector, we identified and validated six TSWV-interacting proteins from Frankliniella occidentalis first-instar larvae. Two proteins, an endocuticle structural glycoprotein and cyclophilin, were able to interact directly with the TSWV attachment protein, GN, in insect cells. The TSWV GN-interacting proteins provide new targets for disrupting the viral disease cycle in the arthropod vector and could be putative determinants of vector competence.


Assuntos
Proteínas de Insetos/metabolismo , Insetos Vetores/metabolismo , Tisanópteros/metabolismo , Tospovirus/metabolismo , Proteínas Estruturais Virais/metabolismo , Animais , Proteínas de Insetos/genética , Insetos Vetores/classificação , Insetos Vetores/genética , Larva/metabolismo , Filogenia , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas , Ligação Proteica , Células Sf9 , Tisanópteros/classificação , Tisanópteros/genética , Nicotiana , Tospovirus/genética , Tospovirus/fisiologia , Proteínas Estruturais Virais/genética
9.
Med Vet Entomol ; 34(4): 394-401, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32438501

RESUMO

In the past decade, leishmaniasis seems to be re-emerging in Balkan countries. There are serious implications that Kosovo is a visceral leishmaniasis endemic region with autochthonous transmission; nevertheless, surveillance of vectors, reservoirs or the disease is not yet established. Gaining knowledge about sandfly vector species is a prerequisite for the development of a monitoring and control plan in the future. After a long gap in research of over 70 years, sandfly studies in Kosovo were resumed in 2014. During this presence/absence study, nine sandfly species were detected: Phlebotomus papatasi, Ph. perfiliewi, Ph. tobbi, Ph. neglectus, Ph. simici, Ph. balcanicus, Ph. alexandri, Ph. mascittii and Sergentomyia minuta. Three species are new with regard to the fauna of Kosovo - Ph. alexandri, Ph. balcanicus and Ph. mascittii. Besides increased diversity, changes in the number of collected specimens and distribution range of species were recorded, with Ph. neglectus being the most dominant species with the widest distribution. Testing of randomly chosen females for Leishmania spp. DNA resulted the in detection of L. tropica in a specimen of Ph. neglectus. The presence of numerous vector species in the sandfly fauna of Kosovo pose a threat for the re-emergence of vector-borne diseases. Therefore, continuous surveillance is recommended with regular updates on vector distribution and abundance.


Assuntos
Leishmania/isolamento & purificação , Phlebotomus/classificação , Animais , DNA de Protozoário , Controle de Insetos , Insetos Vetores/classificação , Insetos Vetores/parasitologia , Kosovo/epidemiologia , Leishmania/genética , Leishmaniose/transmissão , Phlebotomus/parasitologia , Psychodidae , Doenças Transmitidas por Vetores/transmissão
10.
Mem Inst Oswaldo Cruz ; 115: e200218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32696917

RESUMO

BACKGROUND: Southeast Brazil has recently experienced a Yellow Fever virus (YFV) outbreak where the mosquito Haemagogus leucocelaenus was a primary vector. Climatic factors influence the abundance of mosquito vectors and arbovirus transmission. OBJECTIVES: We aimed at describing the population dynamics of Hg. leucocelaenus in a county touched by the recent YFV outbreak. METHODS: Fortnightly egg collections with ovitraps were performed from November 2012 to February 2017 in a forest in Nova Iguaçu, Rio de Janeiro, Brazil. The effects of mean temperature and rainfall on the Hg. leucocelaenus population dynamics were explored. FINDINGS: Hg. leucocelaenus eggs were continuously collected throughout the study, with a peak in the warmer months (December-March). The climatic variables had a time-lagged effect and four weeks before sampling was the best predictor for the positivity of ovitraps and total number of eggs collected. The probability of finding > 50% positive ovitraps increased when the mean temperature was above 24ºC. The number of Hg. leucocelaenus eggs expressively increase when the mean temperature and accumulated precipitation surpassed 27ºC and 100 mm, respectively, although the effect of rainfall was less pronounced. MAIN CONCLUSIONS: Monitoring population dynamics of Hg. leucocelaenus and climatic factors in YFV risk areas, especially mean temperature, may assist in developing climate-based surveillance procedures to timely strengthening prophylaxis and control.


Assuntos
Culicidae/virologia , Florestas , Insetos Vetores/virologia , Dinâmica Populacional , Febre Amarela , Vírus da Febre Amarela/isolamento & purificação , Animais , Brasil , Culicidae/classificação , Insetos Vetores/classificação , Estações do Ano , Temperatura , Vírus da Febre Amarela/genética
11.
Mem Inst Oswaldo Cruz ; 115: e200157, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33206821

RESUMO

BACKGROUND: In Acre state, Brazil, the dissemination of cutaneous leishmaniasis has increased in recent years, with limited knowledge of the potential Leishmania spp. vectors involved. OBJECTIVES: Here, data concerning the sandfly fauna of Brasiléia municipality, Leishmania DNA-detection rates and the identification of blood meal sources of insects captured in 2013-2015 are presented. METHODS: Parasite detection in female sandflies was performed individually by multiplex polymerase chain reaction (PCR) (Leishmania kDNA/sandfly cacophony-gene), with the identification of Leishmania spp. by hsp70-PCR and sequencing. The identification of blood gut-content from fed females was performed by cyt b-PCR and sequencing. FINDINGS: A total of 4,473 sandflies were captured. A subgroup of 864 non-blood-fed females evaluated for the presence of Leishmania DNA showed 2.9% positivity for Leishmania (Viannia) braziliensis and L. (V.) guyanensis. The identification of blood meal sources was performed in 96 blood-fed females, allowing the identification of 13 vertebrate species. In nine/96 fed females, DNA from L. (V.) shawi, L. (V.) guyanensis, L. (V.) braziliensis and Endotrypanum sp. was detected. MAIN CONCLUSIONS: In Brumptomyia sp. and Evandromyia termitophila, the first report of Leishmania DNA-detection is provided in Acre; Nyssomyia shawi is implicated as potential vector of L. (V.) braziliensis and L. (V.) guyanensis for the first time in Brazil.


Assuntos
DNA/análise , Insetos Vetores/genética , Leishmania/genética , Psychodidae/parasitologia , Animais , Brasil , DNA de Protozoário/análise , Feminino , Insetos Vetores/classificação , Insetos Vetores/parasitologia , Leishmania/isolamento & purificação , Leishmaniose Cutânea/transmissão , Reação em Cadeia da Polimerase , Psychodidae/classificação
12.
Parasitology ; 146(2): 213-219, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30009719

RESUMO

The biogeographic histories of parasites and pathogens are infrequently compared with those of free-living species, including their hosts. Documenting the frequency with which parasites and pathogens disperse across geographic regions contributes to understanding not only their evolution, but also the likelihood that they may become emerging infectious diseases. Haemosporidian parasites of birds (parasite genera Plasmodium, Haemoproteus and Leucocytozoon) are globally distributed, dipteran-vectored parasites. To date, over 2000 avian haemosporidian lineages have been designated by molecular barcoding methods. To achieve their current distributions, some lineages must have dispersed long distances, often over water. Here we quantify such events using the global avian haemosporidian database MalAvi and additional records primarily from the Americas. We scored lineages as belonging to one or more global biogeographic regions based on infection records. Most lineages were restricted to a single region but some were globally distributed. We also used part of the cytochrome b gene to create genus-level parasite phylogenies and scored well-supported nodes as having descendant lineages in regional sympatry or allopatry. Descendant sister lineages of Plasmodium, Haemoproteus and Leucocytozoon were distributed in allopatry in 11, 16 and 15% of investigated nodes, respectively. Although a small but significant fraction of the molecular variance in cytochrome b of all three genera could be explained by biogeographic region, global parasite dispersal likely contributed to the majority of the unexplained variance. Our results suggest that avian haemosporidian parasites have faced few geographic barriers to dispersal over their evolutionary history.


Assuntos
Doenças das Aves/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Saúde Global , Haemosporida/fisiologia , Infecções Protozoárias em Animais/epidemiologia , Análise de Variância , Migração Animal , Animais , Doenças das Aves/parasitologia , Doenças das Aves/transmissão , Aves , Doenças Transmissíveis Emergentes/parasitologia , Doenças Transmissíveis Emergentes/transmissão , Doenças Transmissíveis Emergentes/veterinária , Código de Barras de DNA Taxonômico/veterinária , Dípteros/classificação , Dípteros/parasitologia , Variação Genética , Haemosporida/classificação , Insetos Vetores/classificação , Insetos Vetores/parasitologia , Funções Verossimilhança , Filogenia , Filogeografia , Infecções Protozoárias em Animais/parasitologia , Infecções Protozoárias em Animais/transmissão
13.
J Appl Microbiol ; 127(6): 1801-1813, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31509633

RESUMO

AIMS: In this study, binding between the immunodominant membrane protein Imp of the 16SrV-D phytoplasma associated with Flavescence dorée disease (FD-Dp) and insect proteins of vectors and non-vectors of FD-Dp was tested. METHODS AND RESULTS: Six Auchenorrhyncha species, from distantly related groups were selected: Scaphoideus titanus, Euscelidius variegatus, Macrosteles quadripunctulatus, Zyginidia pullula (Cicadomorpha), Ricania speculum and Metcalfa pruinosa (Fulgoromorpha). The vector status of each species was retrieved from the literature or determined by transmission trials in this study. A His-tagged partial Imp protein and a rabbit polyclonal antibody were synthesized and used for Western and Far-Western dot Blot (FWdB) experiments. Total native and membrane proteins (MP) were extracted from entire bodies and organs (gut and salivary glands) of each insect species. FWdB showed decreasing interaction intensities of Imp fusion protein with total proteins from entire bodies of S. titanus, E. variegatus (competent vectors) and M. quadripunctulatus (non-vector), while no interaction signal was detected with the other three species (non-vectors). A strong signal detected upon interaction of FD-D Imp and MP from guts of closely related insects supports the role of this organ as the first barrier to ensure successful transmission. CONCLUSIONS: Our results showed that specific Imp binding, correlated with vector status, is involved in interactions between FD-Dp and insect proteins. SIGNIFICANCE AND IMPACT OF THE STUDY: Integrating knowledge on host-pathogen protein-protein interactions and on insect phylogeny would help to identify the actual range of vectors of phytoplasma strains of economic importance.


Assuntos
Hemípteros/microbiologia , Proteínas de Insetos/metabolismo , Insetos Vetores/microbiologia , Proteínas de Membrana/metabolismo , Phytoplasma/fisiologia , Animais , Proteínas de Bactérias/metabolismo , Hemípteros/química , Hemípteros/classificação , Insetos Vetores/química , Insetos Vetores/classificação , Filogenia , Phytoplasma/química , Doenças das Plantas/microbiologia , Ligação Proteica
14.
Med Vet Entomol ; 33(2): 185-194, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30516832

RESUMO

Flea identification is a significant issue because some species are considered as important vectors of several human pathogens that have emerged or re-emerged recently, such as Bartonella henselae (Rhizobiales: Bartonellaceae) and Rickettsia felis (Rickettsiales: Rickettsiaceae). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been evaluated in recent years for the identification of multicellular organisms, including arthropods. A preliminary study corroborated the usefulness of this technique for the rapid identification of fleas, creating a preliminary database containing the spectra of five species of flea. However, longterm flea preservation in ethanol did not appear to be an adequate method of storage in the context of specimen identification by MALDI-TOF MS profiling. The goal of the present work was to assess the performance of MALDI-TOF MS in the identification of seven flea species [Ctenocephalides felis (Siphonaptera: Pulicidae), Ctenocephalides canis, Pulex irritans (Siphonaptera: Pulicidae), Archaeopsylla erinacei (Siphonaptera: Pulicidae), Leptopsylla taschenbergi (Siphonaptera: Ceratophyllidae), Stenoponia tripectinata (Siphonaptera: Stenoponiidae) and Nosopsyllus fasciatus (Siphonaptera: Ceratophyllidae)] collected in the field and stored in ethanol for different periods of time. The results confirmed that MALDI-TOF MS can be used for the identification of wild fleas stored in ethanol. Furthermore, this technique was able to discriminate not only different flea genera, but also the two congeneric species C. felis and C. canis.


Assuntos
Doenças do Cão/classificação , Infestações por Pulgas/veterinária , Ouriços , Insetos Vetores/classificação , Sifonápteros/classificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária , Argélia , Animais , Cães , Etanol , Infestações por Pulgas/classificação , Espanha , Manejo de Espécimes/veterinária , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
15.
Med Vet Entomol ; 33(4): 498-511, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31172556

RESUMO

African horse sickness (AHS), a disease of equids caused by the AHS virus, is of major concern in South Africa. With mortality reaching up to 95% in susceptible horses and the apparent reoccurrence of cases in regions deemed non-endemic, most particularly the Eastern Cape, epidemiological research into factors contributing to the increase in the range of this economically important virus became imperative. The vectors, Culicoides (Diptera: Ceratopogonidae), are considered unable to proliferate during the unfavourable climatic conditions experienced in winter in the province, although the annual occurrence of AHS suggests that the virus has become established and that vector activity continues throughout the year. Surveillance of Culicoides within the province is sparse and little was known of the diversity of vector species or the abundance of known vectors, Culicoides imicola and Culicoides bolitinos. Surveillance was performed using light trapping methods at selected sites with varying equid species over two winter and two outbreak seasons, aiming to determine diversity, abundance and vector epidemiology of Culicoides within the province. The research provided an updated checklist of Culicoides species within the Eastern Cape, contributing to an increase in the knowledge of AHS vector epidemiology, as well as prevention and control in southern Africa.


Assuntos
Ceratopogonidae/fisiologia , Equidae , Cadeia Alimentar , Insetos Vetores/fisiologia , Vírus da Doença Equina Africana/fisiologia , Animais , Ceratopogonidae/classificação , Feminino , Insetos Vetores/classificação , Masculino , Estações do Ano , África do Sul , Especificidade da Espécie
16.
Med Vet Entomol ; 33(1): 16-30, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30461046

RESUMO

Tabanids, stomoxyine flies, hippoboscids and tsetse flies are the most well-known brachyceran biting flies of livestock. Only a few other higher Diptera have developed the unique mouthparts required for blood feeding. These neglected blood feeders can also have direct effects on hosts through blood loss, and are likely to contribute to the transmission of pathogens. Musca crassirostris (Diptera: Muscidae) is one of the most abundant of the muscid flies with this haematophagous lifestyle; it is widespread in the Palaearctic, Afrotropical and Oriental regions. The present study reviews and summarizes the biology and morphology of this species, and its potential for impact on animals and humans. The study also provides a fully illustrated description of the fly to facilitate its identification, and reviews information on abundance, with a focus on recent trapping surveys in Thailand. When sampled using traps designed for other biting flies, M. crassirostris appears to be four and 45 times more abundant than stomoxyines and tabanids, respectively. High numbers of M. crassirostris in the vicinity of livestock have also been associated with outbreaks of disease, such as that of a fatal plague in bovine farms in Egypt. This calls for a reconsideration of its potential impacts on livestock economics and health, and thus the development of suitable control methods.


Assuntos
Controle de Insetos , Insetos Vetores , Características de História de Vida , Muscidae , Doenças dos Animais , Animais , Comportamento Alimentar , Insetos Vetores/anatomia & histologia , Insetos Vetores/classificação , Insetos Vetores/fisiologia , Gado , Muscidae/anatomia & histologia , Muscidae/classificação , Muscidae/fisiologia , Densidade Demográfica , Tailândia
17.
Med Vet Entomol ; 33(4): 521-529, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31155766

RESUMO

Several species of Leishmania are responsible for leishmaniases in Thailand, although little is known about their transmission. Sergentomyia gemmea has been suspected several times to transmit Leishmania martiniquensis. Some captures carried out in Thailand and Lao People's Democratic Republic have emphasized the scarcity of Se. gemmea, comprising only 1% of the collected females. The sequencing of cytochrome B mtDNA of our specimens showed that our specimens are not grouped with other Se. gemmea previously deposited in GenBank. The latter are grouped with some Se. khawi and Se. hivernus that we processed in the present study. We suspect misidentifications and propose focusing on the most useful characters for identification of Se. gemmea based on the examination of type-specimens. The examination of the ascoids exhibiting anterior spurs is the most important one. However, we also describe Se. raynali n. sp. exhibiting comparable spurs but differing from Se. gemmea by its original cibarium. Finally, the vectorial role of Se. gemmea appears very questionable in the absence of new evidence.


Assuntos
Insetos Vetores/classificação , Psychodidae/classificação , Animais , Citocromos b/análise , DNA Mitocondrial/análise , Feminino , Proteínas de Insetos/análise , Insetos Vetores/anatomia & histologia , Insetos Vetores/genética , Laos , Masculino , Psychodidae/anatomia & histologia , Psychodidae/genética , Análise de Sequência de DNA , Tailândia
18.
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
19.
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
20.
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 de Insetos/classificação , Vírus de RNA/classificação , Animais , Insetos Vetores/classificação , Vírus de Insetos/genética , Vírus de RNA/genética
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