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1.
Curr Microbiol ; 80(5): 172, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37029244

RESUMO

This study investigated the pathogenic potential of Pseudomonas protegens on mosquito larvae of the two species Culex pipiens and Aedes albopictus, representing major threats for disease transmission in the Mediterranean area and worldwide. The bacterium achieved to kill over 90% of the mosquito larvae within 72 h after exposition to a bacterial concentration of 100 million CFU/ml. These lethal effects were concentration dependent and a significantly higher susceptibility was associated with younger larvae of both mosquito species. Significant slowdown of immature (larval and pupal) development and decrease in adult emergence rate after treatment with sub-lethal doses of the bacterium were also detected. This study reports for the first time the insecticidal activity of a root-associated biocontrol bacterium against aquatic mosquito larvae.


Assuntos
Agentes de Controle Biológico , Culicidae , Larva , Pseudomonas , Animais , Aedes/crescimento & desenvolvimento , Aedes/microbiologia , Culex/crescimento & desenvolvimento , Culex/microbiologia , Larva/crescimento & desenvolvimento , Larva/microbiologia , Pseudomonas/patogenicidade , Culicidae/crescimento & desenvolvimento , Culicidae/microbiologia
2.
J Med Entomol ; 59(6): 1891-1897, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36239293

RESUMO

The yellow fever virus is estimated to cause 30,000 deaths each year worldwide, with the majority of cases and deaths occurring in Africa. The virus is also endemic to Central and South America, including northern and western Brazil. The sylvatic cycle of the virus is related to wild and rural areas, with nonhuman primates as the primary host and wild mosquitoes, specifically from the genera Haemagogus, as vectors. The diversity of the mosquito community plays a significant role in the increase of pathogen transmission to humans. In the present study, we detected fluctuation in populations of vector mosquitoes using ovitraps for Culicidae egg collection. The study area is a forest fragment of the Atlantic Forest, one of the most threatened biomes in Brazil. This biome has been suffering significant deforestation due to anthropic activity. Worryingly, the proximity of human populations to forest environments increases the risk of spreading disease from forest fragments to urban areas. Our findings showed that the highest egg abundance occurred in December 2019, with a significant difference (p = 0.005) between rainy and dry seasons. Most eggs were collected during the rainy period. Subsequent quantification of specimens from epidemiologically relevant species hatched from field-collected eggs resulted in 1,131 (86%) Haemagogus leucocelaenus (Dyar & Shannon, 1924), 111 (8%) Aedes terrens (Walker, 1856), 47 (4%) Aedes albopictus (Skuse, 1894), and 21 (2%) Haemagogus janthinomys (Dyar, 1921). Finally, we assessed the behavior of different vector species performing oviposition on the same breeding site. The highest correlation coefficient was observed between Ae. albopictus and Ae. terrens (rho = 0.52) concerning other Culicidae species. Therefore, we believe that Culicidae population surveillance is crucial for disease monitoring since the increase in specimens of a number of vector species influences the emergence of yellow fever cases in nonhuman primates and human populations.


Assuntos
Culicidae , Florestas , Animais , Feminino , Aedes/crescimento & desenvolvimento , Brasil , Culicidae/crescimento & desenvolvimento , Mosquitos Vetores , Primatas , Febre Amarela
3.
Sci Rep ; 12(1): 14392, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999450

RESUMO

The spread of malaria is related to climate change because temperature and rainfall are key parameters of climate change. Fluctuations in temperature affect the spread of malaria by lowering or speeding up its rate of transmission. The amount of rainfall also affects the transmission of malaria by offering a lot of sites suitable for mosquitoes to breed in. However, a high amount of rainfall does not have a great effect. Because of the high malaria incidence and the death rates in African regions, by using malaria incidence data, temperature data and rainfall data collected in 1901-2015, we construct and analyze climate networks to show how climate relates to the transmission of malaria in African countries. Malaria networks show a positive correlation with temperature and rainfall networks, except for the 1981-2015 period, in which the malaria network shows a negative correlation with rainfall.


Assuntos
Mudança Climática , Malária/epidemiologia , Malária/transmissão , África/epidemiologia , Animais , Culicidae/crescimento & desenvolvimento , Incidência , Mosquitos Vetores/crescimento & desenvolvimento , Chuva , Temperatura
4.
J Med Entomol ; 59(4): 1308-1318, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35640207

RESUMO

Psorophora (Grabhamia) dimidiata Cerqueira (1943) was described based on the adult female and male. Later, descriptions of the male and female genitalia were published by Lane (in Neotropical Culicidae, vols. I & II. Editora da Universidade de São Paulo, S. P., Brazil, 1953) and Guedes et al. (in Catalogo ilustrado dos mosquitos da coleção do Instituto Nacional de Endemias Rurais. I. Gênero Psorophora Robineau-Desvoidy, 1827. Rev. Bras. Malariol. Doencas Trop. 12: 3-24; 1965), respectively. Here we describe the pupa and fourth-instar larva and redescribe the adult male and female genitalia and female cibarium. All stages (except the egg) are illustrated. Unambiguous recognition is provided. Distinctions from Ps. cingulata (Fabricius) and possible phylogenetic relationships are discussed.


Assuntos
Culicidae , Larva , Pupa , Animais , Brasil , Culicidae/anatomia & histologia , Culicidae/classificação , Culicidae/crescimento & desenvolvimento , Feminino , Larva/anatomia & histologia , Masculino , Filogenia , Pupa/anatomia & histologia
5.
Parasit Vectors ; 15(1): 23, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35012637

RESUMO

BACKGROUND: Yellow fever virus (YFV) is an arbovirus that, despite the existence of a safe and effective vaccine, continues to cause outbreaks of varying dimensions in the Americas and Africa. Between 2017 and 2019, Brazil registered un unprecedented sylvatic YFV outbreak whose severity was the result of its spread into zones of the Atlantic Forest with no signals of viral circulation for nearly 80 years. METHODS: To investigate the influence of climatic, environmental, and ecological factors governing the dispersion and force of infection of YFV in a naïve area such as the landscape mosaic of Rio de Janeiro (RJ), we combined the analyses of a large set of data including entomological sampling performed before and during the 2017-2019 outbreak, with the geolocation of human and nonhuman primates (NHP) and mosquito infections. RESULTS: A greater abundance of Haemagogus mosquitoes combined with lower richness and diversity of mosquito fauna increased the probability of finding a YFV-infected mosquito. Furthermore, the analysis of functional traits showed that certain functional groups, composed mainly of Aedini mosquitoes which includes Aedes and Haemagogus mosquitoes, are also more representative in areas where infected mosquitoes were found. Human and NHP infections were more common in two types of landscapes: large and continuous forest, capable of harboring many YFV hosts, and patches of small forest fragments, where environmental imbalance can lead to a greater density of the primary vectors and high human exposure. In both, we show that most human infections (~ 62%) occurred within an 11-km radius of the finding of an infected NHP, which is in line with the flight range of the primary vectors. CONCLUSIONS: Together, our data suggest that entomological data and landscape composition analyses may help to predict areas permissive to yellow fever outbreaks, allowing protective measures to be taken to avoid human cases.


Assuntos
Brasil , Culicidae , Surtos de Doenças , Mosquitos Vetores , Febre Amarela/transmissão , Aedes/crescimento & desenvolvimento , Aedes/virologia , Animais , Biodiversidade , Brasil/epidemiologia , Clima , Culicidae/crescimento & desenvolvimento , Culicidae/virologia , Florestas , Humanos , Mosquitos Vetores/classificação , Mosquitos Vetores/crescimento & desenvolvimento , Mosquitos Vetores/virologia , Fatores de Risco , Febre Amarela/epidemiologia
6.
Elife ; 112022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35044908

RESUMO

Predator-prey interactions influence prey traits through both consumptive and non-consumptive effects, and variation in these traits can shape vector-borne disease dynamics. Meta-analysis methods were employed to generate predation effect sizes by different categories of predators and mosquito prey. This analysis showed that multiple families of aquatic predators are effective in consumptively reducing mosquito survival, and that the survival of Aedes, Anopheles, and Culex mosquitoes is negatively impacted by consumptive effects of predators. Mosquito larval size was found to play a more important role in explaining the heterogeneity of consumptive effects from predators than mosquito genus. Mosquito survival and body size were reduced by non-consumptive effects of predators, but development time was not significantly impacted. In addition, Culex vectors demonstrated predator avoidance behavior during oviposition. The results of this meta-analysis suggest that predators limit disease transmission by reducing both vector survival and vector size, and that associations between drought and human West Nile virus cases could be driven by the vector behavior of predator avoidance during oviposition. These findings are likely to be useful to infectious disease modelers who rely on vector traits as predictors of transmission.


Mosquitoes are often referred to as the deadliest animals on earth because some species spread malaria, West Nile virus or other dangerous diseases when they bite humans and other animals. Adult mosquitoes fly to streams, ponds and other freshwater environments to lay their eggs. When the eggs hatch, the young mosquitoes live in the water until they are ready to grow wings and transform into adults. In the water, the young mosquitoes are particularly vulnerable to being eaten by dragonfly larvae, fish and other predators. When adult females are choosing where to lay their eggs, they can use their sense of smell to detect these predators and attempt to avoid them. Along with eating the mosquitoes, the predators may also reduce mosquito populations in other ways. For example, predators can disrupt feeding among young mosquitoes, which may affect the time that it takes for them to grow into adults or the size of their bodies once they reach the adult stage. Although the impacts of different predators have been tested separately in multiple settings, the overall effects of predators on the ability of mosquitoes to spread diseases to humans remain unclear. To address this question, Russell, Herzog et al. used an approach called meta-analysis on data from previous studies. The analysis found that along with increasing the death rates of mosquitoes, the presence of predators also leads to a reduction in the body size of those mosquitoes that survive, causing them to have shorter lifespans and fewer offspring. Russell, Herzog et al. found that one type of mosquito known as Culex ­ which carries West Nile virus ­ avoided laying its eggs near predators. During droughts, increased predation in streams, ponds and other aquatic environments may lead adult female Culex mosquitoes to lay their eggs closer to residential areas with fewer predators. Russell, Herzog et al. propose that this may be one reason why outbreaks of West Nile virus in humans are more likely to occur during droughts. In the future, these findings may help researchers to predict outbreaks of West Nile virus, malaria and other diseases carried by mosquitoes more accurately. Furthermore, the work of Russell, Herzog et al. provides examples of mosquito predators that could be used as biocontrol agents to decrease numbers of mosquitoes in certain regions.


Assuntos
Ambystomatidae , Culicidae/fisiologia , Transmissão de Doença Infecciosa , Peixes , Cadeia Alimentar , Insetos , Mosquitos Vetores/fisiologia , Animais , Tamanho Corporal , Culicidae/crescimento & desenvolvimento , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Mosquitos Vetores/crescimento & desenvolvimento , Filogenia , Dinâmica Populacional
7.
J Med Entomol ; 59(1): 173-183, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34661674

RESUMO

The family Culicidae is represented by 244 species in Argentina, many of them with epidemiological importance. DNA barcodes are effective tools for identifying mosquito species, for knowing genetic variability, and for establishing phylogenetic relationships. This work aims to explore mosquito diversity employing different species delimitation approaches and to establish formally a DNA barcode library for the Argentinian mosquito fauna. Barcode fragments of 80 specimens of Argentinian mosquitoes of 28 species of the genera Aedeomyia Theobald (Diptera: Culicidae), Anopheles Meigen (Diptera: Culicidae), Coquillettidia Dyar (Diptera: Culicidae), Culex L. (Diptera: Culicidae), Haemagogus Williston (Diptera: Culicidae), Mansonia Blanchard (Diptera: Culicidae), Nyssorhynchus Blanchard (Diptera: Culicidae), Ochlerotatus Lynch-Arribálzaga (Diptera: Culicidae), Psorophora Robinneau-Desvoidy (Diptera: Culicidae) and Uranotaenia Lynch-Arribálzaga (Diptera: Culicidae) were sequenced. Another 82 sequences were obtained from public databases to establish the phylogenetic relationships using Maximum Likelihood and Bayesian Inference, and the species boundaries based on three approaches (ABGD, GMYC, and mPTP). Sixteen of the 28 species sequenced were recovered as monophyletic, of which 12 were also recognized as molecular operational taxonomic units according to the three methodologies. The disparity between morphology and barcode-based identifications could be explained by synonymy, species complexes occurrence, hybridization, incomplete lineage sorting, or the effect of the geographical scale of sampling. Twenty of the 28 sequenced species are new barcodes for Argentina and 11 are the first for science. This increases from 31 to 52 (12.7 to 21.31%) and from six to 10 (28.57 to 47.62%) the number of species and genera, respectively, with barcode sequences in Argentina. New species records are provided.


Assuntos
Distribuição Animal , Culicidae/classificação , Código de Barras de DNA Taxonômico , Animais , Argentina , Culicidae/crescimento & desenvolvimento , Feminino , Larva/classificação , Larva/crescimento & desenvolvimento , Masculino , Filogenia , Pupa/classificação , Pupa/crescimento & desenvolvimento
8.
J Med Entomol ; 59(1): 78-82, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34430976

RESUMO

Several species of mosquitoes respond to the presence of kairomones released by larvivorous predators during oviposition habitat selection and larval development. These responses may differ among mosquito species and do not always correlate with larval survival. This study examined the responses of the mosquito Culiseta longiareolata Macquart (Diptera: Culicidae) to kairomones released by three species of fish, Gambusia affinis (Cyprinodontiformes: Poeciliidae), Aphanius mento (Cyprinodontiformes: Cyprinodontidae) and Garra rufa (Cypriniformes: Cyprinidae) during oviposition. In addition, the study examined the effects of kairomones released by Gm. affinis on larval development and survival. Results show that ovipositing female avoided cues from the two larvivorous fish species but not the algivorous Gr. rufa. In addition, developing larvae metamorphosed slower and showed increased mortality when exposed to fish-released kairomones. Culiseta longiareolata larvae are known as dominant competitors, and the straightforward responses of both larvae and adult female to fish-released kairomones may be explained by the lack of additional sources of larval stress other than the presence of predators.


Assuntos
Sinais (Psicologia) , Culicidae/fisiologia , Cyprinidae/fisiologia , Ciprinodontiformes/fisiologia , Oviposição , Feromônios/metabolismo , Animais , Culicidae/efeitos dos fármacos , Culicidae/crescimento & desenvolvimento , Ecossistema , Peixes Listrados/fisiologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Oviposição/efeitos dos fármacos , Feromônios/farmacologia
9.
Molecules ; 26(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34641433

RESUMO

Poly(lactic acid) (PLA) is an attractive candidate for replacing petrochemical polymers because it is fully biodegradable. This study investigated the potential of PLA as a sustainable and environmentally friendly alternative material that can be developed into commercially viable wearable mosquito repellent devices with desirable characteristics. PLA strands containing DEET and IR3535 were prepared by twin screw extrusion compounding and simultaneously functioned as plasticizers for the polymer. The plasticizing effect was investigated by thermal and rheological studies. DSC studies showed that the addition of DEET and IR3535 into PLA strands reduced the glass transition temperature consistent with predictions of the Fox equation, thus proving their efficiency as plasticizers. The rheology of molten samples of neat PLA and PLA/repellents blends, evaluated at 200 °C, was consistent with shear-thinning pseudoplastic behaviour. Raman studies revealed a nonlinear concentration gradient for DEET in the PLA strand, indicating non-Fickian Type II transport controlling the desorption process. Release data obtained at 50 °C showed initial rapid release followed by a slower, near constant rate at longer times. The release rate data were fitted to a novel modification of the Peppas-Sahlin desorption model.


Assuntos
Culicidae/crescimento & desenvolvimento , Repelentes de Insetos/química , Plastificantes/química , Poliésteres/química , Polímeros/química , Animais , Culicidae/efeitos dos fármacos , Reologia , Temperatura
10.
J Med Entomol ; 58(6): 2524-2532, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34313772

RESUMO

Culiseta (Allotheobaldia) longiareolata (Macquart) (Diptera: Culicidae) is an ornithophilic mosquito species that occurs in the southern Palaearctic Region from the Azores to Central Asia, the Ethiopian Region, India, and Pakistan. Although it has a widespread distribution range, the species was only recently reported in Western and Central Europe. Between 2017 and 2020, larvae, pupae, and adults of Cs. longiareolata (n = 161) were found at 13 distinct locations in Belgium (n = 4) and The Netherlands (n = 9). Collected mosquitoes were morphologically identified and the identification was then validated by COI DNA barcoding. These are the first records of the species in the above-mentioned countries. The present results suggest that Cs. longiareolata could be increasing its distribution range in temperate regions, indicating a warming climate. As the species might be a potential vector of bird pathogens (e.g., West Nile virus), its spread in Western Europe is noteworthy.


Assuntos
Distribuição Animal , Culicidae/fisiologia , Mosquitos Vetores/fisiologia , Animais , Bélgica , Culicidae/crescimento & desenvolvimento , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Países Baixos , Pupa/crescimento & desenvolvimento , Pupa/fisiologia
11.
J Med Entomol ; 58(6): 2264-2273, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34144599

RESUMO

This study presents the diversity of mosquitoes collected from communes, endemic with malaria and dengue, located in Khanh Hoa and Binh Phuoc Provinces, Vietnam. A total of 10,288 mosquitoes were collected in the village and forested sites using standard larval dippers, cow-baited traps, ultra-violet light traps, and mechanical aspirators. Mosquito taxa were identified morphologically and species complexes/groups were further characterized molecularly. Five genera of mosquitoes were morphologically identified: Anopheles Meigen (21 species), Aedes Meigen (2 species), Culex Linnaeus (5 species), Mansonia Blanchard sp., and Armigeres Theobald sp. The PCR-based identification methods allowed the distinction of members of Maculatus Group, Funestus Group, and Dirus Complex; and DNA barcodes enabled the further identification of the Barbirostris Complex. Data reported here include the first report of An. saeungae Taai & Harbach and An. wejchoochotei Taai & Harbach from Vietnam, and re-emphasizes the significance of using molecular data in an integrated systematic approach to identify cryptic species and better understand their role in disease transmission.


Assuntos
Distribuição Animal , Culicidae/fisiologia , Animais , Culicidae/classificação , Culicidae/crescimento & desenvolvimento , Larva/classificação , Larva/crescimento & desenvolvimento , Larva/fisiologia , Vietnã
12.
Malar J ; 20(1): 244, 2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059053

RESUMO

BACKGROUND: Spatio-temporal trends in mosquito-borne diseases are driven by the locations and seasonality of larval habitat. One method of disease control is to decrease the mosquito population by modifying larval habitat, known as larval source management (LSM). In malaria control, LSM is currently considered impractical in rural areas due to perceived difficulties in identifying target areas. High resolution drone mapping is being considered as a practical solution to address this barrier. In this paper, the authors' experiences of drone-led larval habitat identification in Malawi were used to assess the feasibility of this approach. METHODS: Drone mapping and larval surveys were conducted in Kasungu district, Malawi between 2018 and 2020. Water bodies and aquatic vegetation were identified in the imagery using manual methods and geographical object-based image analysis (GeoOBIA) and the performances of the classifications were compared. Further, observations were documented on the practical aspects of capturing drone imagery for informing malaria control including cost, time, computing, and skills requirements. Larval sampling sites were characterized by biotic factors visible in drone imagery and generalized linear mixed models were used to determine their association with larval presence. RESULTS: Imagery covering an area of 8.9 km2 across eight sites was captured. Larval habitat characteristics were successfully identified using GeoOBIA on images captured by a standard camera (median accuracy = 98%) with no notable improvement observed after incorporating data from a near-infrared sensor. This approach however required greater processing time and technical skills compared to manual identification. Larval samples captured from 326 sites confirmed that drone-captured characteristics, including aquatic vegetation presence and type, were significantly associated with larval presence. CONCLUSIONS: This study demonstrates the potential for drone-acquired imagery to support mosquito larval habitat identification in rural, malaria-endemic areas, although technical challenges were identified which may hinder the scale up of this approach. Potential solutions have however been identified, including strengthening linkages with the flourishing drone industry in countries such as Malawi. Further consultations are therefore needed between experts in the fields of drones, image analysis and vector control are needed to develop more detailed guidance on how this technology can be most effectively exploited in malaria control.


Assuntos
Aeronaves/estatística & dados numéricos , Controle de Doenças Transmissíveis/métodos , Culicidae/fisiologia , Ecossistema , Malária/prevenção & controle , Controle de Mosquitos/instrumentação , Animais , Culicidae/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia
13.
J Am Mosq Control Assoc ; 37(1): 10-19, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33857319

RESUMO

Mosquito-borne diseases are a major public health concern in the Caribbean. Domestic water-storage containers are preferred breeding habitats for synanthropic mosquito species, among which Aedes aegypti stands out due to its role in arbovirus transmission. To determine the microenvironmental features associated with container-dwelling mosquitoes, a house-to-house cross-sectional entomological survey was carried out in 9 Dominican provinces affected by Zika virus in 2016. All containers with the potential to store water were sampled, all immature mosquitoes were collected, and information on the type, capacity, volume of stored water, building material, presence of flowers, and house location was documented. The specimens were identified and larval indices (House index [HI], Container index [CI], Breteau index [BI], and Ae. aegypti Breeding Percentage) were applied. A total of 665 dwellings were surveyed across 30 neighborhoods. A total of 1,420 water-filled container habitats were sampled, 19.3% of which harbored immature mosquitoes of 5 species, including 4 important vectors. The dominance of Ae. aegypti was marked, as it was present in all sampled neighborhoods, inhabiting 272 containers (19.1%). Larval indices were higher than the threshold values accepted (5% for the HI and BI, and 3% for the CI) in almost all neighborhoods. The presence of Aedes spp. was associated with the serviceability of water-holding containers (χ2 = 16.56522; P < 0.001), and the difference in volume between water-holding containers was associated with the presence of Aedes spp. infection (χ2 = 4; P < 0.001), the containers up to 5 liters being the most infested. This is the first entomological research based on synanthropic mosquito breeding habitats that cover urban areas of the 3 macro-regions of the Dominican Republic.


Assuntos
Distribuição Animal , Culicidae/fisiologia , Meio Ambiente , Animais , Culicidae/crescimento & desenvolvimento , República Dominicana , Feminino , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Pupa/crescimento & desenvolvimento , Pupa/fisiologia
14.
Bioprocess Biosyst Eng ; 44(9): 1819-1829, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33822248

RESUMO

The aqueous seed extract of Annona squamosa L. was used as a reducing and stabilizing agent for the synthesis of silver nanoparticles (AgNPs). The formation of AgNPs in aqueous silver nitrate solution after the addition of the extract was indicated by a colour change from pale yellow to dark brown corresponding to a λmax at 430 nm. The phytochemicals in the extract, responsible for efficient capping and stabilization of the nanoparticles, were identified by FTIR. Powder XRD pattern demonstrated the polycrystalline nature of the AgNPs. TEM image confirmed that AgNPs were spherical in shape and the average particle size was found to be 22 nm. Further, the nanoparticles exhibited good catalytic activity towards the degradation of coomassie brilliant blue dye and demonstrated significant antibacterial activity. Their larvicidal activity against mosquito larvae showed a LC50 value 22.44 µg/mL against III instars. In addition, AgNPs positively influenced the germination of chickpea seeds.


Assuntos
Annona/química , Química Verde , Inseticidas , Nanopartículas Metálicas/química , Processos Fotoquímicos , Extratos Vegetais/química , Prata/química , Animais , Culicidae/crescimento & desenvolvimento , Inseticidas/síntese química , Inseticidas/química , Inseticidas/farmacologia , Larva/crescimento & desenvolvimento
15.
J Med Entomol ; 58(3): 1197-1201, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33554243

RESUMO

Non-lethal predator-prey interactions during the immature stages can cause significant changes to mosquito life history traits and their ability to transmit pathogens as adults. Treatment manipulations using mosquitoes Aedes aegypti (L.) and Toxoryhnchites rutilus (Coquillett) were performed during the immature stages to explore the potential impacts of non-lethal interactions on adult susceptibility to infection, disseminated infection and saliva infection of Ae. aegypti following ingestion of Zika virus-infected blood. Treatments inducing density reduction resulted in reduced development time and survivorship to adulthood. However, effects of treatment did not alter infection, dissemination, or saliva infection. These observations indicate that, while non-lethal predation may impact some traits that influence population dynamics and transmission of pathogens, there were no direct effects on mosquito-arbovirus interactions.


Assuntos
Aedes/crescimento & desenvolvimento , Culicidae/fisiologia , Traços de História de Vida , Mosquitos Vetores/crescimento & desenvolvimento , Comportamento Predatório , Zika virus/fisiologia , Aedes/virologia , Animais , Culicidae/crescimento & desenvolvimento , Culicidae/virologia , Cadeia Alimentar , Larva/crescimento & desenvolvimento , Larva/fisiologia , Larva/virologia , Mosquitos Vetores/virologia
16.
J Agric Food Chem ; 69(4): 1224-1233, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33480687

RESUMO

To further study the structure-activity relationship of gossypol, hemigossypol (1) and its derivatives (2-23) were successfully designed via structure simplification and chemically synthesized. The anti-tobacco mosaic virus (TMV), fungicidal, and insecticidal activities of them were tested systematically. Most of these derivatives exhibited excellent anti-TMV activity. Furthermore, these compounds also exhibited broad-spectrum fungicidal activities against 14 kinds of phytopathogenic fungi. In particular, hemigossypol acid lactone (7) was stable in the air. In terms of biological activity, it not only showed anti-TMV activity (inhibitory rates of 70.3, 65.4 and 72.4% at 500 µg/mL for inactivation, curative, and protection activity in vivo, respectively) comparable to ningnanmycin but also exhibited higher insecticidal activity against mosquito larvae (60%/0.25 mg/kg) than the commercial species rotenone. None of hemigossypol and the tested derivatives showed antitumor activities.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antivirais/síntese química , Antivirais/farmacologia , Fungicidas Industriais/síntese química , Fungicidas Industriais/farmacologia , Inseticidas/síntese química , Inseticidas/farmacologia , Animais , Antineoplásicos/química , Antivirais/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Linhagem Celular Tumoral , Culicidae/efeitos dos fármacos , Culicidae/crescimento & desenvolvimento , Desenho de Fármacos , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Fungicidas Industriais/química , Gossipol/química , Gossipol/farmacologia , Humanos , Inseticidas/química , Doenças das Plantas/microbiologia , Doenças das Plantas/virologia , Relação Estrutura-Atividade , Vírus do Mosaico do Tabaco/efeitos dos fármacos
17.
PLoS One ; 16(1): e0245087, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33444320

RESUMO

Inter-relationships among mosquito vectors, Plasmodium parasites, human ecology, and biotic and abiotic factors, drive malaria risk. Specifically, rural landscapes shaped by human activities have a great potential to increase the abundance of malaria vectors, putting many vulnerable people at risk. Understanding at which point the abundance of vectors increases in the landscape can help to design policies and interventions for effective and sustainable control. Using a dataset of adult female mosquitoes collected at 79 sites in malaria endemic areas in the Brazilian Amazon, this study aimed to (1) verify the association among forest cover percentage (PLAND), forest edge density (ED), and variation in mosquito diversity; and to (2) test the hypothesis of an association between landscape structure (i.e., PLAND and ED) and Nyssorhynchus darlingi (Root) dominance. Mosquito collections were performed employing human landing catch (HLC) (peridomestic habitat) and Shannon trap combined with HLC (forest fringe habitat). Nyssorhynchus darlingi abundance was used as the response variable in a generalized linear mixed model, and the Shannon diversity index (H') of the Culicidae community, PLAND, and the distance house-water drainage were used as predictors. Three ED categories were also used as random effects. A path analysis was used to understand comparative strengths of direct and indirect relationships among Amazon vegetation classes, Culicidae community, and Ny. darlingi abundance. Our results demonstrate that Ny. darlingi is negatively affected by H´ and PLAND of peridomestic habitat, and that increasing these variables (one-unit value at ß0 = 768) leads to a decrease of 226 (P < 0.001) and 533 (P = 0.003) individuals, respectively. At the forest fringe, a similar result was found for H' (ß1 = -218; P < 0.001) and PLAND (ß1 = -337; P = 0.04). Anthropogenic changes in the Amazon vegetation classes decreased mosquito biodiversity, leading to increased Ny. darlingi abundance. Changes in landscape structure, specifically decreases in PLAND and increases in ED, led to Ny. darlingi becoming the dominant species, increasing malaria risk. Ecological mechanisms involving changes in landscape and mosquito species composition can help to understand changes in the epidemiology of malaria.


Assuntos
Biodiversidade , Culicidae/crescimento & desenvolvimento , Atividades Humanas , Insetos Vetores/crescimento & desenvolvimento , Malária/parasitologia , Floresta Úmida , Animais , Brasil , Geografia , Modelos Lineares , Modelos Teóricos , Análise de Componente Principal
18.
J Med Entomol ; 58(1): 428-438, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-32623459

RESUMO

The purpose of this study was to determine the ecology of the common arboviral mosquito vectors in Mombasa, Kilifi and Malindi urban areas of coastal Kenya. Mosquito larvae were collected using standard dippers and pipettes. Egg survivorship in dry soil was evaluated by collecting soil samples from dry potential larval developmental sites, re-hydrating them for hatching and rearing of the eventual larvae to adults. Adult mosquitoes were collected with CDC light traps and BG-Sentinel traps. All blood-fed females were tested for bloodmeal origin. Mosquitoes were screened for arboviruses using RT-qPCR. Overall, the predominant species were Culex quinquefasciatus (Say) 72.4% (n = 2,364) and Aedes aegypti (L.), 25.7%, (n = 838). A total of 415 larval developmental sites were identified indoors (n = 317) and outdoors (n = 98). The most productive larval developmental sites, both indoors and outdoors, were assorted small containers, water tanks, drainages, drums, and jerricans. Overall, 62% (n = 18) of the soil samples collected were positive for larvae which were used as a proxy to measure the presence of eggs. The mosquitoes fed on humans (29.8%) and chickens (3.7%). Of 259 mosquitoes tested for viral infection, 11.6% were positive for Flavivirus only. The most productive larval developmental sites for arboviral vectors indoors were small containers, water tanks, jerricans, and drums whereas small containers, water tanks, drainage channels, buckets, tires, and water troughs were the productive larval developmental sites outdoors.


Assuntos
Arbovírus/fisiologia , Culicidae/fisiologia , Mosquitos Vetores/fisiologia , Distribuição Animal , Animais , Cidades , Culicidae/crescimento & desenvolvimento , Quênia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Longevidade , Mosquitos Vetores/crescimento & desenvolvimento , Óvulo/crescimento & desenvolvimento , Óvulo/fisiologia , Pupa/crescimento & desenvolvimento , Pupa/fisiologia
19.
Med Vet Entomol ; 35(1): 1-29, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32997823

RESUMO

Mosquitoes (Diptera: Culicidae) were collected in Finland between 2012 and 2018 to determine the species present and their distributions. In total, 52 466 specimens from 1031 collections formed the basis for the preparation of distribution maps for each of the 40 species that were collected. Anopheles maculipennis s.s., An. claviger, Aedes geminus and Ochlerotatus sticticus are confirmed on mainland Finland after previous records were uncertain or absent. Coquillettidia richiardii, Culiseta morsitans, Cs. ochroptera, Culex territans, Cx. torrentium, Oc. leucomelas, Oc. nigrinus, Oc. pullatus and Oc. punctodes occur more widely than previously reported. Three species, Ae. rossicus, Cs. subochrea and Oc. cyprius were not collected, although Ae. rossicus was subsequently found in Lapland by another researcher. No invasive species were collected. Ochlerotatus communis, an aggressive biter, was the most commonly encountered species. Larval collection data suggest that several species may have up to three generations per year in Finland, with Cx. torrentium and Cx. pipiens having at least two, and Oc. communis and Oc. punctor regularly found as larvae across the summer. These data, especially when coupled with historical records, are vital for monitoring species which have significant vector potential, particularly when faced with a warming climate.


Assuntos
Distribuição Animal , Culicidae/fisiologia , Traços de História de Vida , Animais , Culicidae/crescimento & desenvolvimento , Finlândia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Dinâmica Populacional
20.
J Med Entomol ; 58(3): 1210-1218, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33300038

RESUMO

The rapid and economical monitoring of mosquitos is imperative to understanding the dynamics of both disease vectors and nuisance species. In light of technological advances in mosquito sampling and DNA sequencing, health agencies can now utilize the full potential of metabarcoding pipelines for rapid and standardizable surveillance. Here, we describe mosquito spatial and temporal variation, with particular focus on Mansonia Blanchard species, in the Madeira (Rondônia State) and the Ribeira (São Paulo) watersheds, Brazil using metabarcoding of the D2 rDNA marker. Sampling and molecular pipelines were used to evaluate the taxonomic contribution of mosquitos in pools of culicids collected en masse from macrophyte-roots (immatures) and from Mosquito Magnet traps and protected human landings (adults). Results for adult captures are comparable to morphological diagnoses and clarify previously unknown temporal and spatial species turnover. Metabarcoding of immature stages also confirmed the extent of the geographical distribution of some species and each taxon's association with macrophyte species. Given the benefits of metabarcoding, such as taxonomic acuity, high throughput processing, and objectivity, we suggest such techniques should be more fully incorporated into culicid monitoring schemes. The metabarcoding protocol described herein paired with standardized field sampling schemes, when used by mosquito monitoring professionals, offers substantial improvements in terms of practicality, speed and cost.


Assuntos
Culicidae/classificação , Código de Barras de DNA Taxonômico , Entomologia/métodos , Animais , Brasil , Culicidae/crescimento & desenvolvimento , Larva/classificação , Larva/crescimento & desenvolvimento , Pupa/classificação , Pupa/crescimento & desenvolvimento
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