RESUMEN
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.
Asunto(s)
Insectos Vectores , Polimorfismo Genético , Moscas Tse-Tse , Animales , Camerún , Moscas Tse-Tse/genética , Insectos Vectores/genética , Insectos Vectores/clasificación , Distribución Animal , Filogenia , ADN Intergénico/genética , Femenino , Control de Insectos , Masculino , ADN Espaciador Ribosómico/análisis , ADN Espaciador Ribosómico/genética , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: The city of El Pedregal grew out of a desert, following an agricultural irrigation project in southern Peru. OBJECTIVES: To describe infestation patterns by triatomines and bed bugs and their relationship to migration and urbanization. METHODS: We conducted door-to-door entomological surveys for triatomines and bed bugs. We assessed spatial clustering of infestations and compared the year of construction of infested to un-infested households. To gain a better understanding of the context surrounding triatomine infestations, we conducted in-depth interviews with residents to explore their migration histories, including previous experiences with infestation. FINDINGS: We inspected 5,164 households for Triatoma infestans (known locally as the Chirimacha); 21 (0.41%) were infested. These were extremely spatially clustered (Ripley's K p-value < 0.001 at various spatial scales). Infested houses were older than controls (Wilcoxon rank-sum: W = 33; p = 0.02). We conducted bed bug specific inspections in 34 households; 23 of these were infested. These were spatially dispersed across El Pedregal, and no difference was observed in construction age between bed bug infested houses and control houses (W = 6.5, p = 0.07). MAIN CONCLUSIONS: The establishment of agribusiness companies in a desert area demanded a permanent work force, leading to the emergence of a new city. Migrant farmers, seeking work opportunities or escaping from adverse climatic events, arrived with few resources, and constructed their houses with precarious materials. T. infestans, a Chagas disease vector, was introduced to the city and colonized houses, but its dispersal was constrained by presence of vacant houses. We discuss how changes in the socioeconomic and agricultural landscape can increase vulnerability to vector-borne illnesses.
Asunto(s)
Chinches , Enfermedad de Chagas , Insectos Vectores , Triatoma , Animales , Perú , Enfermedad de Chagas/transmisión , Insectos Vectores/clasificación , Insectos Vectores/parasitología , Insectos Vectores/fisiología , Humanos , Triatoma/parasitología , Riego Agrícola , ViviendaRESUMEN
BACKGROUND: Kissing bugs are the vectors of Trypanosoma cruzi, the etiological agent of Chagas disease (CD). Despite their epidemiological relevance, kissing bug species are under sampled in terms of their diversity and it is unclear what biases exist in available kissing bug data. Under climate change, range maps for kissing bugs may become less accurate as species shift their ranges to track climatic tolerance. OBJECTIVES: Quantify inventory completeness in available kissing bug data. Assess how well range maps are at conveying information about current distributions and potential future distributions subject to shift under climate change. Intersect forecasted changes in kissing bug distributions with contemporary sampling gaps to identify regions for future sampling of the group. Identify whether a phylogenetic signal is present in expert range knowledge as more closely related species may be similarly well or lesser understood. METHODS: We used species distribution models (SDM), specifically constructed from Bayesian additive regression trees, with Bioclim variables, to forecast kissing bug distributions into 2100 and intersect these with current sampling gaps to identify priority regions for sampling. Expert range maps were assessed by the agreement between the expert map and SDM generated occurrence probability. We used classical hypothesis testing methods as well as tests of phylogenetic signal to meet our objectives. FINDINGS: Expert range maps vary in their quality of depicting current kissing bug distributions. Most expert range maps decline in their ability to convey information about kissing bug occurrence over time, especially in under sampled areas. We found limited evidence for a phylogenetic signal in expert range map performance. MAIN CONCLUSIONS: Expert range maps are not a perfect account of species distributions and may degrade in their ability to accurately convey distribution knowledge under future climates. We identify regions where future sampling of kissing bugs will be crucial for completing biodiversity inventories.
Asunto(s)
Cambio Climático , Insectos Vectores , Animales , Insectos Vectores/clasificación , Reduviidae , Distribución Animal , Enfermedad de Chagas/transmisión , Teorema de Bayes , Filogenia , AméricasRESUMEN
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.
Asunto(s)
Enfermedad de Chagas , Insectos Vectores , Triatominae , Trypanosoma cruzi , Enfermedad de Chagas/transmisión , Animales , Insectos Vectores/clasificación , Insectos Vectores/parasitología , Brasil/epidemiología , Triatominae/clasificación , Triatominae/parasitología , Humanos , Factores de Riesgo , Medición de Riesgo , EcosistemaRESUMEN
Within the research conducted in the years 2016-2022 in the area of Volovsky Mountains in Slovakia, 63,950 biting midges were collected during 74 trapping sessions. The aim of the study was to identify species composition of biting midges, their host preference and potential transmission of parasites by these insects under natural conditions. The collected biting midges fell into 29 species and the most common were the Culicoides (C. obsoletus/C. scoticus/C. montanus) that accounted for 47.9% of the collected biting midges. Identification of species was based on the morphology of biting midges and the use of molecular methods. We confirmed positive suckling results on red deer in three samples namely C. montanus, C. scoticus and C. deltus. We examined these samples for the presence of Onchocerca worm DNA. We confirmed the presence of O. flexuosa DNA in one C. deltus sample. The host preference of biting midges was identified by molecular technique that involved sequencing a 350-bp sequence of the mitochondrial cytochrome b gene (cyt b). The presence of Onchocerca flexuosa DNA in C. deltus was confirmed by sequencing of fragments of mitochondrial genes cox1. The sequences matched the previously published sequences for O. flexuosa. Data on high prevalence of infections caused by Onchocerca worms in red deer in Slovakia have already been published and indicated favourable conditions for the vectors and a suitable environment for parasite circulation in Slovakia. According to the authors' knowledge, this was the first ever detection of O. flexuosa in C. deltus in wild nature.
Asunto(s)
Ceratopogonidae , Ciervos , Onchocerca , Oncocercosis , Animales , Ciervos/parasitología , Ceratopogonidae/clasificación , Ceratopogonidae/genética , Ceratopogonidae/parasitología , Eslovaquia , Onchocerca/genética , Onchocerca/clasificación , Onchocerca/aislamiento & purificación , Oncocercosis/veterinaria , Oncocercosis/transmisión , Oncocercosis/parasitología , Oncocercosis/epidemiología , Insectos Vectores/parasitología , Insectos Vectores/clasificación , Citocromos b/genéticaRESUMEN
Triatominae are recognized as vectors of Trypanosoma cruzi, a protozoan which is the etiological agent of Chagas disease. A specimen of Triatoma delpontei was found at Porto Murtinho in Mato Grosso do Sul State, Brazil. This is the first report of the occurrence of T. delpontei to the state of Mato Grosso do Sul, Brazil. With the present finding, the total number of triatomines recorded in Mato do Grosso do Sul reaches 17 species, while T. delpontei, previously recorded only from Rio Grande do Sul, is now recorded to a second Brazilian state. Based on the information available in the literature, a meticulous and organized compilation has been crafted, highlighting the cytogenetics differentiations of the species occurring in this state. This work emphasizes the importance of continuous research and surveillance on Triatominae, recognized as vectors of T. cruzi.
Asunto(s)
Enfermedad de Chagas , Insectos Vectores , Triatoma , Animales , Brasil , Triatoma/clasificación , Insectos Vectores/clasificación , Enfermedad de Chagas/transmisión , Trypanosoma cruziRESUMEN
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.
Asunto(s)
Insectos Vectores , Psychodidae , Animales , Psychodidae/clasificación , Brasil , Insectos Vectores/clasificación , Densidad de Población , Femenino , Masculino , Estaciones del Año , EcosistemaRESUMEN
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.
Asunto(s)
Ecosistema , Bosques , Insectos Vectores , Psychodidae , Animales , Psychodidae/fisiología , Psychodidae/clasificación , Insectos Vectores/fisiología , Insectos Vectores/clasificación , Ecuador , Masculino , Femenino , Leishmaniasis Cutánea/transmisión , Biodiversidad , HumanosRESUMEN
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.
Asunto(s)
Insectos/microbiología , Pseudomonas/fisiología , Animales , Agentes de Control Biológico , Interacciones Huésped-Patógeno , Insectos Vectores/clasificación , Insectos Vectores/microbiología , Insectos/clasificación , Pseudomonas/metabolismo , Simbiosis , Factores de Virulencia/metabolismoRESUMEN
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.
Asunto(s)
Enfermedad de Chagas/parasitología , ADN Protozoario/genética , Didelphis/parasitología , Insectos Vectores/parasitología , Triatominae/parasitología , Trypanosoma cruzi/genética , Animales , Biopsia , Enfermedad de Chagas/diagnóstico , Perros , Humanos , Insectos Vectores/clasificación , Reacción en Cadena de la Polimerasa , Triatominae/clasificación , Trypanosoma cruzi/aislamiento & purificación , XenodiagnósticoRESUMEN
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.
Asunto(s)
Ceratopogonidae/fisiología , Vuelo Animal/fisiología , Insectos Vectores/fisiología , Animales , Ceratopogonidae/clasificación , Análisis por Conglomerados , Femenino , Insectos Vectores/clasificación , Lituania , Estaciones del Año , TemperaturaRESUMEN
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.
Asunto(s)
Proteínas de Insectos/metabolismo , Insectos Vectores/metabolismo , Thysanoptera/metabolismo , Tospovirus/metabolismo , Proteínas Estructurales Virales/metabolismo , Animales , Proteínas de Insectos/genética , Insectos Vectores/clasificación , Insectos Vectores/genética , Larva/metabolismo , Filogenia , Enfermedades de las Plantas/virología , Plantas Modificadas Genéticamente , Unión Proteica , Células Sf9 , Thysanoptera/clasificación , Thysanoptera/genética , Nicotiana , Tospovirus/genética , Tospovirus/fisiología , Proteínas Estructurales Virales/genéticaRESUMEN
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.
Asunto(s)
Leishmania/aislamiento & purificación , Phlebotomus/clasificación , Animales , ADN Protozoario , Control de Insectos , Insectos Vectores/clasificación , Insectos Vectores/parasitología , Kosovo/epidemiología , Leishmania/genética , Leishmaniasis/transmisión , Phlebotomus/parasitología , Psychodidae , Enfermedades Transmitidas por Vectores/transmisiónRESUMEN
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.
Asunto(s)
Culicidae/virología , Bosques , Insectos Vectores/virología , Dinámica Poblacional , Fiebre Amarilla , Virus de la Fiebre Amarilla/aislamiento & purificación , Animales , Brasil , Culicidae/clasificación , Insectos Vectores/clasificación , Estaciones del Año , Temperatura , Virus de la Fiebre Amarilla/genéticaRESUMEN
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.
Asunto(s)
ADN/análisis , Insectos Vectores/genética , Leishmania/genética , Psychodidae/parasitología , Animales , Brasil , ADN Protozoario/análisis , Femenino , Insectos Vectores/clasificación , Insectos Vectores/parasitología , Leishmania/aislamiento & purificación , Leishmaniasis Cutánea/transmisión , Reacción en Cadena de la Polimerasa , Psychodidae/clasificaciónRESUMEN
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.
Asunto(s)
Enfermedades de las Aves/epidemiología , Enfermedades Transmisibles Emergentes/epidemiología , Salud Global , Haemosporida/fisiología , Infecciones Protozoarias en Animales/epidemiología , Análisis de Varianza , Migración Animal , Animales , Enfermedades de las Aves/parasitología , Enfermedades de las Aves/transmisión , Aves , Enfermedades Transmisibles Emergentes/parasitología , Enfermedades Transmisibles Emergentes/transmisión , Enfermedades Transmisibles Emergentes/veterinaria , Código de Barras del ADN Taxonómico/veterinaria , Dípteros/clasificación , Dípteros/parasitología , Variación Genética , Haemosporida/clasificación , Insectos Vectores/clasificación , Insectos Vectores/parasitología , Funciones de Verosimilitud , Filogenia , Filogeografía , Infecciones Protozoarias en Animales/parasitología , Infecciones Protozoarias en Animales/transmisiónRESUMEN
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.
Asunto(s)
Hemípteros/microbiología , Proteínas de Insectos/metabolismo , Insectos Vectores/microbiología , Proteínas de la Membrana/metabolismo , Phytoplasma/fisiología , Animales , Proteínas Bacterianas/metabolismo , Hemípteros/química , Hemípteros/clasificación , Insectos Vectores/química , Insectos Vectores/clasificación , Filogenia , Phytoplasma/química , Enfermedades de las Plantas/microbiología , Unión ProteicaRESUMEN
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.
Asunto(s)
Ceratopogonidae/fisiología , Equidae , Cadena Alimentaria , Insectos Vectores/fisiología , Virus de la Enfermedad Equina Africana/fisiología , Animales , Ceratopogonidae/clasificación , Femenino , Insectos Vectores/clasificación , Masculino , Estaciones del Año , Sudáfrica , Especificidad de la EspecieRESUMEN
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.
Asunto(s)
Enfermedades de los Perros/clasificación , Infestaciones por Pulgas/veterinaria , Erizos , Insectos Vectores/clasificación , Siphonaptera/clasificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/veterinaria , Argelia , Animales , Perros , Etanol , Infestaciones por Pulgas/clasificación , España , Manejo de Especímenes/veterinaria , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodosRESUMEN
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.