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1.
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
2.
PLoS Negl Trop Dis ; 14(7): e0008450, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32628662

RESUMO

BACKGROUND: Zika virus (ZIKV) disease outbreaks have been occurring in South America since 2015, and has spread to North America. Because birth defects and cases of Guillain Barré have been associated with infection with ZIKV, this has drawn global attention. ZIKV is generally considered an Aedes-transmitted pathogen. The transmission of ZIKV through blood by Aedes mosquito bites has been recognized as the major transmission route. However, it is not clear whether there are other transmission routes that can cause viral infection in mosquitos. The aim of the present study is to describe the susceptibility of Armigeres subalbatus, which often develop in human waste lagoons, to ZIKV, through oral infection in adult mosquitoes and urine infection in larvae. METHODOLOGY/PRINCIPAL FINDINGS: Five-day-old female Ar. subalbatus ingested infectious blood meals containing ZIKV. After 4, 7, and 10 days of ingesting infectious blood meals, ZIKV could be detected in the midguts, salivary glands, ovaries, and collected saliva of mosquitoes. The ZIKV infection rate (IR) on day 10 reached 40% in salivary glands and 13% in saliva, indicating that these mosquitoes were able to transmit ZIKV. In addition, ZIKV infection was also discovered in mosquito ovaries, suggesting the possibility of vertical transmission of virus. Moreover, Ar. subalbatus transmitted ZIKV to infant mice bitten by infectious mosquitoes. In a second experiment, 1st-instar larvae of Ar. subalbatus were reared in water containing ZIKV and human urine. After pupation, pupae were placed in clean water and transferred to a mosquito cage for emergence. Although ZIKV RNA was detected in all of the larvae tested, ZIKV was not detected in the saliva of any adult Ar. subalbatus. Considering that there are more uncontrollable factors in nature than in the laboratory environment, the possibility that the virus is transmitted to adult mosquitoes via larvae is very small period. CONCLUSIONS/SIGNIFICANCE: Adult Ar. subalbatus could be infected with ZIKV and transmit ZIKV through mosquito bites. Therefore, in many rural areas in China and in undeveloped areas of other Asian countries, the management of human waste lagoons in the prevention and control of Zika disease should be considered. Corresponding adjustments and modifications should also be made in prevention and control strategies against ZIKV.


Assuntos
Culicidae/virologia , Mosquitos Vetores/virologia , Infecção por Zika virus/transmissão , Zika virus/fisiologia , Animais , Culicidae/crescimento & desenvolvimento , Culicidae/fisiologia , Feminino , Humanos , Larva/virologia , Camundongos , Mosquitos Vetores/crescimento & desenvolvimento , Mosquitos Vetores/fisiologia , Saliva/virologia , Zika virus/genética , Zika virus/isolamento & purificação , Infecção por Zika virus/urina , Infecção por Zika virus/virologia
3.
Malar J ; 19(1): 38, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969158

RESUMO

BACKGROUND: The association between irrigation and the proliferation of adult mosquitoes including malaria vectors is well known; however, irrigation schemes are treated as homogenous spatio-temporal units, with little consideration for how larval breeding varies across space and time. The objective of this study was to estimate the spatio-temporal distribution of pools of water facilitating breeding at the Bwanje Valley Irrigation Scheme (BVIS) in Malawi, Africa as a function of environmental and anthropogenic characteristics. METHODS: Irrigation structure and land cover were quantified during the dry and rainy seasons of 2016 and 2017, respectively. These data were combined with soil type, irrigation scheduling, drainage, and maintenance to model suitability for mosquito breeding across the landscape under three scenarios: rainy season, dry season with limited water resources, and a dry season with abundant water resources. RESULTS: Results demonstrate seasonal, asymmetrical breeding potential and areas of maximum breeding potential as a function of environmental characteristics and anthropogenic influence in each scenario. The highest percentage of suitable area for breeding occurs during the rainy season; however, findings show that it is not merely the amount of water in an irrigated landscape, but the management of water resources that determines the aggregation of water bodies. In each scenario, timing and direction of irrigation along with inefficient drainage render the westernmost portion of BVIS the area of highest breeding opportunity, which expands and contracts seasonally in response to water resource availability and management decisions. CONCLUSIONS: Changes in the geography of breeding potential across irrigated spaces can have profound effects on the distribution of malaria risk for those living in close proximity to irrigated agricultural schemes. The methods presented are generalizable across geographies for estimating spatio-temporal distributions of breeding risk for mosquitoes in irrigated schemes, presenting an opportunity for greater geographically targeted strategies for management.


Assuntos
Irrigação Agrícola , Culicidae/crescimento & desenvolvimento , Mosquitos Vetores/crescimento & desenvolvimento , Animais , Culicidae/fisiologia , Humanos , Malária/transmissão , Malaui , Mosquitos Vetores/fisiologia , Chuva , Fatores de Risco , Estações do Ano , Análise Espaço-Temporal
4.
J Photochem Photobiol B ; 203: 111774, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31931386

RESUMO

Zeolitic imidazole framework (ZIF) is an emerging class of metal organic frameworks exhibiting unique features such as crystalline nature with tunable pore size, large surface area and biocompatible nature. Exceptional thermal and chemical stabilities of ZIF-L make it a suitable candidate for biomedical applications. The present study has focused on the single step fabrication of catechin encapsulated ZIF-L and evaluation of its antibiofilm efficiency, larvicidal activity and dye degradation ability. The as- prepared CA@ZIF-L nanocomposite was characterized by spectroscopic and microscopic techniques. The results revealed that the CA@ZIF-L showed significant toxicity against mosquito larvae in a dose dependent manner with the IC50 63.43±1.25 µg/mL. CA@ZIF-L showed dose dependent reduction of biofilm formation in both ATCC and clinical MRSA strains. In addition, CA@ZIF-L exhibited excellent photocatalytic activity with around 92% degradation of methylene blue under direct sunlight. Overall, the present work highlights the possibility of employing the multifunctional CA@ZIF-L nanocomposite as a suitable material for biomedical and photocatalytic applications.


Assuntos
Biofilmes/efeitos dos fármacos , Catequina/química , Estruturas Metalorgânicas/química , Nanocompostos/toxicidade , Zeolitas/química , Animais , Catálise , Culicidae/efeitos dos fármacos , Culicidae/crescimento & desenvolvimento , Imidazóis/química , Larva/efeitos dos fármacos , Luz , Staphylococcus aureus Resistente à Meticilina/fisiologia , Azul de Metileno/química , Nanocompostos/química , Tamanho da Partícula , Fotólise/efeitos da radiação
5.
Cell Rep ; 29(12): 3796-3806.e4, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31851913

RESUMO

Plasmodium falciparum gametocytes infect mosquitoes and are responsible for malaria transmission. New interventions that block transmission could accelerate malaria elimination. Gametocytes develop within erythrocytes and activate protein export pathways that remodel the host cell. Plasmepsin V (PMV) is an aspartyl protease that is required for protein export in asexual parasites, but its function and essentiality in gametocytes has not been definitively proven, nor has PMV been assessed as a transmission-blocking drug target. Here, we show that PMV is expressed and can be inhibited specifically in P. falciparum stage I-II gametocytes. PMV inhibitors block processing and export of gametocyte effector proteins and inhibit development of stage II-V gametocytes. Gametocytogenesis in the presence of sublethal inhibitor concentrations results in stage V gametocytes that fail to infect mosquitoes. Therefore, PMV primes gametocyte effectors for export, which is essential for the development and fitness of gametocytes for transmission to mosquitoes.


Assuntos
Ácido Aspártico Endopeptidases/antagonistas & inibidores , Culicidae/crescimento & desenvolvimento , Inibidores Enzimáticos/farmacologia , Gametogênese/efeitos dos fármacos , Malária Falciparum/prevenção & controle , Plasmodium falciparum/crescimento & desenvolvimento , Proteínas de Protozoários/antagonistas & inibidores , Animais , Ácido Aspártico Endopeptidases/metabolismo , Culicidae/efeitos dos fármacos , Culicidae/parasitologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/parasitologia , Humanos , Estágios do Ciclo de Vida , Malária Falciparum/enzimologia , Malária Falciparum/parasitologia , Malária Falciparum/transmissão , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/enzimologia , Proteínas de Protozoários/metabolismo
6.
Sci Rep ; 9(1): 19093, 2019 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-31836789

RESUMO

West Nile Virus (WNV) is a mosquito-borne infection that can cause serious illness in humans. Surveillance for WNV primarily focuses on a measure of infection prevalence in the Culex spp. mosquitos, its primary vectors, known as the Minimum Infection Rate (MIR). The calculation of MIR for a given area considers the number of mosquitos tested, but not the relative effort to collect mosquitos, leading to a potential underestimation of the uncertainty around the estimate. We performed Value of Information analysis on simulated data sets including a range of mosquito trap densities in two well-studied counties in Illinois between 2005 and 2016 to determine the relative error introduced into MIR associated with changing the density of mosquito traps. We found that low trap density increases the potential for error in MIR estimation, and that it does so synergistically with low true MIR values. We propose that these results could be used to better estimate uncertainty in WNV risk.


Assuntos
Culicidae/crescimento & desenvolvimento , Culicidae/virologia , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/fisiologia , Animais , Simulação por Computador , Intervalos de Confiança , Análise de Regressão
7.
Artigo em Inglês | MEDLINE | ID: mdl-31731533

RESUMO

Species interactions that influence the performance of the exotic mosquito Culex pipiens can have important effects on the transmission risk of West Nile virus (WNV). Invasive plants that alter the vegetation communities of ephemeral ground pools may facilitate or resist the spread of C. pipiens (L.) by altering allochthonous inputs of detritus in those pools. To test this hypothesis, we combined field surveys of roadside stormwater ditches with a laboratory microcosm experiment to examine relationships between C. pipiens performance and water quality in systems containing detritus from invasive Phragmites australis (Cav.) Trin. Ex Steud., introduced Schedonorus arundinaceus (Schreb.) Dumort., or native Juncus effusus L. or Typha latifolia L. In ditches, C. pipiens abundance was unrelated to detritus species but female C. pipiens were significantly larger from ditches with S. arundinaceus and smaller with J. effusus. Larger and smaller C. pipiens were also produced in microcosms provisioned with S. arundinaceus and J. effusus, respectively, yet the per capita rate of population of change did not vary. Larger females from habitats with S. arundinaceus were likely caused by faster decay rates of S. arundinaceus and resultant increases in microbial food, but lower survival as a result of fouling and higher tannin-lignin concentrations resulted in little changes to overall population performance. Larger female mosquitoes have been shown to have greater potential for transmitting arboviruses. Our findings suggest that changed community-level interactions from plant invasions in urban ephemeral ground pools can affect the fitness of C. pipiens and possibly increase WNV risk.


Assuntos
Culex/virologia , Culicidae/crescimento & desenvolvimento , Ecossistema , Festuca , Vírus do Nilo Ocidental , Animais , Arbovirus , Feminino , Poaceae , Febre do Nilo Ocidental/epidemiologia
8.
Parasit Vectors ; 12(1): 462, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578155

RESUMO

BACKGROUND: Assessing adult mosquito populations is an important component of disease surveillance programs and ecosystem health assessments. Inference from adult trapping datasets involves comparing populations across space and time, but comparisons based on different trapping methods may be biased if traps have different efficiencies or sample different subsets of the mosquito community. METHODS: We compared four widely-used trapping methods for adult mosquito data collection in Kruger National Park (KNP), South Africa: Centers for Disease Control miniature light trap (CDC), Biogents Sentinel trap (BG), Biogents gravid Aedes trap (GAT) and a net trap. We quantified how trap choice and sampling effort influence inferences on the regional distribution of mosquito abundance, richness and community composition. RESULTS: The CDC and net traps together collected 96% (47% and 49% individually) of the 955 female mosquitoes sampled and 100% (85% and 78% individually) of the 40 species or species complexes identified. The CDC and net trap also identified similar regional patterns of community composition. However, inference on the regional patterns of abundance differed between these traps because mosquito abundance in the net trap was influenced by variation in weather conditions. The BG and GAT traps collected significantly fewer mosquitoes, limiting regional comparisons of abundance and community composition. CONCLUSIONS: This study represents the first systematic assessment of trapping methods in natural savanna ecosystems in southern Africa. We recommend the CDC trap or the net trap for future monitoring and surveillance programs.


Assuntos
Biodiversidade , Culicidae/classificação , Culicidae/crescimento & desenvolvimento , Entomologia/métodos , Densidade Demográfica , Animais , África do Sul , Análise Espacial
9.
J Am Mosq Control Assoc ; 35(3): 228-232, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31647712

RESUMO

An unmanned aircraft system (UAS; i.e., drone) with an attached multispectral camera was used to quantify accumulated surface water on a 0.54-km2 tidal marsh that abuts San Francisco Bay, CA, USA. The results of the survey showed unequal accumulation of surface water and provided information for focused inspections of potential mosquito breeding areas and identified areas where existing ditches needed improvement for increasing water circulation in the marsh to reduce mosquito breeding. The UAS was also outfitted with a high-magnification zoom video camera and piloted at varying heights to measure the video camera's ability to visualize immature mosquitoes in 2 small containers of contrasting colors during simulation tests in a marsh habitat. Immature mosquitoes could be seen clearly in white or black containers at heights up to 14 and 8 m, respectively. An artificial intelligence algorithm identified mosquito larvae and pupae in videos of the white tray with 94.1% and 52.8% accuracy, respectively. Together, our studies show that an UAS equipped with multispectral and zoom cameras provides a means for vector control agencies to rapidly and quantitatively assess the landscape for the presence of surface water and mosquito larvae.


Assuntos
Aeronaves , Distribuição Animal , Inteligência Artificial , Culicidae , Animais , Culicidae/crescimento & desenvolvimento , Ecossistema , Larva/crescimento & desenvolvimento , Vigilância da População/métodos , Pupa/crescimento & desenvolvimento , Áreas Alagadas
10.
Bull Soc Pathol Exot ; 112(2): 96-104, 2019.
Artigo em Francês | MEDLINE | ID: mdl-31478619

RESUMO

Big cities have thrived on all continents, so have domestic and industrial wastes not to mention the often irrational use of agricultural inputs (fertilizers and pesticides) detrimental to plants and animals. One hundred and eighty million tons of fertilizers and 2.4 million tons of pesticides are spread every year worldwide. Such pollutions, whether urban or rural, have a significant impact on the biology of mosquitoes. Today some urban spaces have properly become a land of plenty for mosquitoes. The combined use of fertilizer and pesticides in the country, quite paradoxically also favor their proliferation. Ironically the very reasons that account for the multitudes of mosquitoes are the exact reasons responsible for the depletion of biodiversity.


Assuntos
Agricultura , Culicidae/crescimento & desenvolvimento , Poluição Ambiental/efeitos adversos , Atividades Humanas , Mosquitos Vetores/crescimento & desenvolvimento , Agricultura/estatística & dados numéricos , Animais , Patógenos Transmitidos pelo Sangue/isolamento & purificação , Cidades/estatística & dados numéricos , Reservatórios de Doenças/microbiologia , Reservatórios de Doenças/parasitologia , Reservatórios de Doenças/estatística & dados numéricos , Reservatórios de Doenças/virologia , Poluição Ambiental/estatística & dados numéricos , Fertilizantes/efeitos adversos , Atividades Humanas/estatística & dados numéricos , Atividades Humanas/tendências , Humanos , Praguicidas/efeitos adversos , População Urbana/estatística & dados numéricos
11.
Bull Soc Pathol Exot ; 112(2): 105-113, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31478623

RESUMO

Mosquitoes occupy a major health problem, as a potential vector for the transmission of many pathogens, the most important of which in Morocco are Plasmodium parasites and West Nile fever virus. Acquiring knowledge about the biotypology of these mosquitoes is an essential step in any control strategy. Thus, the objective of this study is to draw up an inventory of the culicidian fauna in the Fez region (North-central part of Morocco) and to determine the physicochemical parameters influencing the production of mosquito larvae of aquatic habitats in this area. Mosquito larvae of the extant biotopes were sampled every two months between November 2015 and December 2016, by means of the "dipping" method. The physicochemical parameters of the various larval biotopes were collected six times during the year of follow-up. Mosquito species were identified using morphological criteria. The results were analyzed using ecological indices and the generalized linear model (Poisson model) on R software. The identification of the 1,122 mosquito larvae collected from the various studied breeding areas revealed the presence of 11 species belonging to two subfamilies (Culicinae and Anophelinae) and five genera (Anopheles, Culex, Culiseta, Aedes, and Uranotaenia). Anopheles were observed in small numbers in permanent, stagnant, and shallow habitats. The larvae of An. maculipennis s. l. (major vector of malaria in Morocco) were collected. Culex larvae, especially Cx. pipiens (the main vector of WNV in Morocco), were collected in the majority of the larval habitats and on the different types of environments. Two other species of Culex, which plays a significant role in the transmission of WNV, were also collected, particularly, Cx. perexiguus and Cx. theileri. The results found, via this first study of its kind at the regional level, also made it possible to update the list of Culicidae species reported in the Fez region. Four new species have been recorded: Aedes flavescens, Uranotaenia unguiculata, Culiseta longiareolata, and Culex perexiguus. The results of this study will contribute to the provision of information for entomological surveillance and to better plan and guide vector control activities at local and national levels.


Assuntos
Culicidae/citologia , Ecossistema , Larva/citologia , Microbiologia da Água , Água/análise , Água/parasitologia , Animais , Contagem de Células , Fenômenos Químicos , Culicidae/crescimento & desenvolvimento , Vetores de Doenças , Humanos , Larva/crescimento & desenvolvimento , Marrocos/epidemiologia , Mosquitos Vetores , Urbanização , Poluição da Água/análise , Poluição da Água/estatística & dados numéricos
12.
J Am Mosq Control Assoc ; 35(2): 151-154, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31442133

RESUMO

During June through September 2018, the North Shore Mosquito Abatement District evaluated a quality control protocol for larvicide-treated catch basins that allowed for comparisons of larvicides with different modes of action. Results suggest that when applied at a rate of 2 tablespoons (approximately 20 g of product) per basin, these larvicides (VectoLex® FG Lysinibacillus sphaericus, Natular™ G30 Spinosad, and Altosid® Pellets Methoprene) could reduce the need for retreatment for up to 4 wk or longer. Using this same protocol, Spheratax® SPH (50G) L. sphaericus was applied to a subset of approximately 900 basins and met the threshold for retreatment 1.1 wk postapplication. Despite these larvicide applications, pupae continued to be observed in non-Altosid® treated basins, suggesting 100% mortality may not be attainable.


Assuntos
Culicidae , Inseticidas , Controle de Mosquitos , Animais , Chicago , Culicidae/crescimento & desenvolvimento , Larva
13.
J Am Mosq Control Assoc ; 35(1): 67-70, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31442185

RESUMO

Roof gutters on houses that have become inundated with leaf litter and cannot drain properly are an often-overlooked man-made container habitat that is suitable for mosquito larval development. In order to reduce the amount of leaf litter debris in gutters, many homeowners install debris screens, commonly referred to as "gutter guards," on their roof gutters, but no study has examined the effect of gutter guards on mosquito production. The objective of this research was to determine the extent to which different types of gutter guards affect mosquito colonization and abundance of juvenile mosquitoes in gutter habitats. Three experimental gutters, each with 1 of 3 treatments (control with no gutter guard, a metal lock-in mesh screen gutter guard, or a foam filter gutter insert), were placed at 5 field locations to monitor mosquito colonization and production over 8 wk. Pupae were collected daily, and eclosed adults were identified to species. Mosquitoes colonized and larvae developed in all gutters regardless of the presence of a guard, although those with the foam filter guards were least likely to be colonized (P < 0.001). Once colonized, the control gutters without a gutter guard had the lowest mosquito abundance (P < 0.001), and the metal lock-in gutters had the highest abundance (P < 0.001). The results suggest that if standing water exists in a gutter, gutter guards are not an effective tool for mosquito control.


Assuntos
Culicidae , Ecossistema , Habitação , Controle de Mosquitos , Animais , Culicidae/crescimento & desenvolvimento , Equipamentos e Provisões , Illinois , Larva/crescimento & desenvolvimento , Controle de Mosquitos/instrumentação
14.
J Med Entomol ; 56(5): 1270-1274, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31144723

RESUMO

The Chiang Mai (CM) form of the genus Lutzia, subgenus Metalutzia, in Thailand is diagnosed and formally named Lt. chiangmaiensis Somboon & Harbach, n. sp. The species is contrasted with related species, and information is provided on its bionomics and distribution.


Assuntos
Culicidae/classificação , Animais , Culicidae/anatomia & histologia , Culicidae/crescimento & desenvolvimento , Feminino , Larva/anatomia & histologia , Larva/classificação , Larva/crescimento & desenvolvimento , Masculino , Pupa/anatomia & histologia , Pupa/classificação , Pupa/crescimento & desenvolvimento , Tailândia
16.
Sci Total Environ ; 675: 260-272, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31030133

RESUMO

Early warning systems for vector-borne diseases (VBDs) prediction are an ecological application where data from the interface of several environmental components can be used to predict future VBD transmission. In general, models for early warning systems only consider average environmental conditions ignoring variation in weather variables, despite the prediction from Schmalhausen's law about the importance of environmental variability for biological systems. We present results from a long-term mosquito surveillance program from Harris County, Texas, USA, where we use time series analysis techniques to study the abundance and West Nile virus (WNV) infection patterns in the local primary vector, Culex quinquefasciatus Say. We found that, as predicted by Schmalhausen's law, mosquito abundance was associated with the standard deviation and kurtosis of environmental variables. By contrast, WNV infection rates were associated with 8-month lagged temperature, suggesting environmental conditions during overwintering might be key for WNV amplification during summer outbreaks. Finally, model validation showed that seasonal autoregressive models successfully predicted mosquito WNV infection rates up to 2 months ahead, but did rather poorly at predicting mosquito abundance, a result that might reflect impacts of vector control for mosquito population reduction, geographic scale, and other artifacts generated by operational constraints of mosquito surveillance systems.


Assuntos
Culicidae/crescimento & desenvolvimento , Tempo (Meteorologia) , Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental , Animais , Culicidae/virologia , Humanos , Controle de Mosquitos , Mosquitos Vetores , Texas/epidemiologia
17.
J Insect Sci ; 19(2)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30843583

RESUMO

The complex biologies of pestiferous mosquito species complicate the development of a single, across the board effective control measure. The use of traditional biological control through predators, parasitoids, and microbes, though part of a multimodal, integrated pest management approach, is scant in current standard mosquito control operations. At this time, traditional, whole organism mosquito biocontrol agents are not commercially available, and if their integration into a release program is desired, they must be developed in-house. The aim of our program was to incorporate releasing natural enemies to disrupt and suppress the target pest mosquito's population by matching the agent with the target's biology, before or concurrent to pesticide use. A current focus is suppressing peridomestic, container breeders of high medical significance, such as Aedes aegypti (Linnaeus), (Diptera, Culicidae) and Aedes albopictus (Skuse) (Diptera, Culicidae), through larval reduction with augmentative releases of laboratory-reared, native mosquito assassins Toxorhynchites rutilus septentrionalis (Dyar & Knab). When raised in communal settings, Tx. rutilus' aggressive feeding behavior and cannibalistic tendencies require an extreme loss tolerance in adult production rates. In addition, offering prey mosquitoes exclusively as Tx. rutilus' juvenile food extends larval development by multiple days. While this may be desirous in the wild, it proves inefficient during production. Here, we provide an individual rearing method as well as an alternative diet protocol, which maximizes the adult yield while achieving quick development.


Assuntos
Culicidae/crescimento & desenvolvimento , Entomologia/métodos , Animais , Feminino , Masculino , Controle Biológico de Vetores
18.
Theor Popul Biol ; 126: 51-58, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30779889

RESUMO

Managing infectious diseases is a world public health issue, plagued by uncertainties. In this paper, we analyze the problem of viable control of a dengue outbreak under uncertainty. For this purpose, we develop a controlled Ross-Macdonald model with mosquito vector control by fumigation, and with uncertainties affecting the dynamics; both controls and uncertainties are supposed to change only once a day, then remain stationary during the day. The robust viability kernel is the set of all initial states such that there exists at least a strategy of insecticide spraying which guarantees that the number of infected individuals remains below a threshold, for all times, and whatever the sequences of uncertainties. Having chosen three nested subsets of uncertainties - a deterministic one (without uncertainty), a medium one and a large one - we can measure the incidence of the uncertainties on the size of the kernel, in particular on its reduction with respect to the deterministic case. The numerical results show that the viability kernel without uncertainties is highly sensitive to the variability of parameters - here the biting rate, the probability of infection to mosquitoes and humans, and the proportion of female mosquitoes per person. So, a robust viability analysis is a possible tool to reveal the importance of uncertainties regarding epidemics control.


Assuntos
Dengue/epidemiologia , Dengue/prevenção & controle , Modelos Biológicos , Controle de Mosquitos , Animais , Colômbia/epidemiologia , Culicidae/crescimento & desenvolvimento , Surtos de Doenças , Feminino , Humanos , Insetos Vetores/crescimento & desenvolvimento , Inseticidas/uso terapêutico , Viabilidade Microbiana , Controle de Mosquitos/métodos , Processos Estocásticos
19.
J Biol Dyn ; 13(sup1): 2-22, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29701130

RESUMO

Mosquitoes are vectors for many diseases that cause significant mortality and morbidity. As mosquito populations expand their range, they may undergo mate-finding Allee effects such that their ability to successfully reproduce becomes difficult at low population density. With new technology, creating target specific gene modification may be a viable method for mosquito population control. We develop a mathematical model to investigate the effects of releasing transgenic mosquitoes into newly established, low-density mosquito populations. Our model consists of two life stages (aquatic and adults), which are divided into three genetically distinct groups: heterogeneous and homogeneous transgenic that cause female infertility and a homogeneous wild type. We perform analytical and numerical analyses on the equilibria to determine the level of saturation needed to eliminate mosquitoes in a given area. This model demonstrates the potential for a gene drive system to reduce the spread of invading mosquito populations.


Assuntos
Culicidae/crescimento & desenvolvimento , Culicidae/genética , Especificidade de Hospedeiro , Modelos Biológicos , Animais , Animais Geneticamente Modificados , Simulação por Computador , Fertilidade , Heterozigoto , Homozigoto , Dinâmica Populacional
20.
Pest Manag Sci ; 75(4): 923-934, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30178568

RESUMO

BACKGROUND: To prevent the risk of mosquito-borne disease outbreaks, larval source management remains the most sustainable and effective mosquito control strategy. The present study aimed to determine the influence of environmental characteristics of mosquito larval habitats in an urban area of Marseille, France. Fourteen sites containing water were monitored every 2 weeks from May to October 2015 for mosquito species occurrence and larval density, and environmental parameters were measured at each visit. Rapid and accurate species identification of mosquito larvae was performed using an innovative MALDI-TOF MS method. RESULTS: A total of 6753 larvae (L1-L4) and pupae were collected, of which 35.8% (n = 2418) were speciated using MALDI-TOF MS. Correct identifications were obtained for 2259 specimens (93.4%). A total of five mosquito species were found, including Aedes (Ae.) albopictus, Culex (Cx.) p. pipiens, Cx. hortensis, Cx. impudicus, and Culiseta (Cs.) longiareolata. Larvae of the Culex genus were predominant in both density and distribution. Small, shaded pools of shallow water favored Ae. albopictus colonization, whereas the wide distribution of Cx. p. pipiens demonstrated that this species was weakly influenced by environmental changes. CONCLUSIONS: The present work confirms that MALDI-TOF MS is a useful tool for mosquito speciation and suggests that understanding the environmental factors associated with the occurrence and density of mosquito species at the larval stage in Marseille may aid in the future implementation of mosquito control programs. © 2018 Society of Chemical Industry.


Assuntos
Distribuição Animal , Culicidae/fisiologia , Ecossistema , Controle de Mosquitos/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Cidades , Culicidae/crescimento & desenvolvimento , França , Larva/crescimento & desenvolvimento , Larva/fisiologia , Densidade Demográfica , Pupa/crescimento & desenvolvimento , Pupa/fisiologia , Especificidade da Espécie
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