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Pesticides and Mosquito Control  

Science.gov (United States)

This factsheet from the Environmental Protection Agency includes several summary documents on the problem of mosquito-borne diseases and the pesticides used to control mosquitoes. The resources cover issues from mosquito biology through the EPA's recent findings on the negative health impacts of Malathion.

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HERBAL CONTROL OF MOSQUITO LARVAE  

Directory of Open Access Journals (Sweden)

Full Text Available Mosquitoes are the vectors for the dreadful diseases of mankind. For control of larval stages of mosquito, herbal plant extracts/ botanical insecticides are being tried. In the present study aqueous extract of some traditional medicinal herbal plants i.e. Neem (Azadirechta indica, Tobacco (Nicotiana tabacum, Turmeric (Curcuma longa, Tulasi (Ocimum santum, and Ginger (Zingiber officinale were tested for their Larvicidal activity. The successful attempt is made to kill the larvae, the premature stage of mosquitoes by using safe and socio-economical herbal plant extract mixtures. Ginger+Tobacco, Neem+Tobbaco and Ginger Neem, Turmeric, Tobacco and Tulasi showed highest larvicidal activity. The results obtained show that this plant material exhibited larvicidal activity and could be considered as potent natural larvicidal agent without any toxic effects.

Chaudhari Priyanka S, Chaudhari SV* Jangam Sampada, Shinde JS, Wankhede Sneha

2013-04-01

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Insecticide-resistant mosquitoes and malaria control.  

Science.gov (United States)

The emergence of insecticide-resistant mosquitoes strongly challenges the fight against mosquito-borne diseases, in particular malaria. In this paper, we formulate a system of nonlinear difference equations for malaria transmission cycle. Our model incorporates compartments for insecticide-resistant mosquitoes, where mutation is the only evolutionary force involved in the occurrence of resistant allele in the mosquito population. By deriving an epidemiological threshold, the global stability of the disease and the resistance-free fixed point is established for reduced recruitment rates of resistant mosquitoes. Furthermore, by employing numerical techniques, we showed that the mosquito-human transmission cycle of malaria and its prevalence could be impacted by mutation rate, the personal protection of hosts and the density of mosquitoes. Our results highlight that given a large mosquito population, the presence of even a small number of resistant mosquitoes to an insecticide could make the insecticide ineffective for malaria control. This suggests the need for effective insecticide management strategy, alternate mosquito control approaches, educating the public about personal protection and reduction of mosquito population in a given environment. PMID:24657875

Blayneh, Kbenesh W; Mohammed-Awel, Jemal

2014-06-01

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North American Wetlands and Mosquito Control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Wetlands are valuable habitats that provide important social, economic, and ecological services such as flood control, water quality improvement, carbon sequestration, pollutant removal, and primary/secondary production export to terrestrial and aquatic food chains. There is disagreement about the need for mosquito control in wetlands and about the techniques utilized for mosquito abatement and their impacts upon wetlands ecosystems. Mosquito control in wetlands is a complex issue influenced ...

2012-01-01

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North American wetlands and mosquito control.  

Science.gov (United States)

Wetlands are valuable habitats that provide important social, economic, and ecological services such as flood control, water quality improvement, carbon sequestration, pollutant removal, and primary/secondary production export to terrestrial and aquatic food chains. There is disagreement about the need for mosquito control in wetlands and about the techniques utilized for mosquito abatement and their impacts upon wetlands ecosystems. Mosquito control in wetlands is a complex issue influenced by numerous factors, including many hard to quantify elements such as human perceptions, cultural predispositions, and political climate. In spite of considerable progress during the last decades, habitat protection and environmentally sound habitat management still remain inextricably tied to politics and economics. Furthermore, the connections are often complex, and occur at several levels, ranging from local businesses and politicians, to national governments and multinational institutions. Education is the key to lasting wetlands conservation. Integrated mosquito abatement strategies incorporate many approaches and practicable options, as described herein, and need to be well-defined, effective, and ecologically and economically sound for the wetland type and for the mosquito species of concern. The approach will certainly differ in response to disease outbreaks caused by mosquito-vectored pathogens versus quality of life issues caused by nuisance-biting mosquitoes. In this contribution, we provide an overview of the ecological setting and context for mosquito control in wetlands, present pertinent information on wetlands mosquitoes, review the mosquito abatement options available for current wetlands managers and mosquito control professionals, and outline some necessary considerations when devising mosquito control strategies. Although the emphasis is on North American wetlands, most of the material is applicable to wetlands everywhere. PMID:23222252

Rey, Jorge R; Walton, William E; Wolfe, Roger J; Connelly, C Roxanne; O'Connell, Sheila M; Berg, Joe; Sakolsky-Hoopes, Gabrielle E; Laderman, Aimlee D

2012-12-01

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North American Wetlands and Mosquito Control  

Directory of Open Access Journals (Sweden)

Full Text Available Wetlands are valuable habitats that provide important social, economic, and ecological services such as flood control, water quality improvement, carbon sequestration, pollutant removal, and primary/secondary production export to terrestrial and aquatic food chains. There is disagreement about the need for mosquito control in wetlands and about the techniques utilized for mosquito abatement and their impacts upon wetlands ecosystems. Mosquito control in wetlands is a complex issue influenced by numerous factors, including many hard to quantify elements such as human perceptions, cultural predispositions, and political climate. In spite of considerable progress during the last decades, habitat protection and environmentally sound habitat management still remain inextricably tied to politics and economics. Furthermore, the connections are often complex, and occur at several levels, ranging from local businesses and politicians, to national governments and multinational institutions. Education is the key to lasting wetlands conservation. Integrated mosquito abatement strategies incorporate many approaches and practicable options, as described herein, and need to be well-defined, effective, and ecologically and economically sound for the wetland type and for the mosquito species of concern. The approach will certainly differ in response to disease outbreaks caused by mosquito-vectored pathogens versus quality of life issues caused by nuisance-biting mosquitoes. In this contribution, we provide an overview of the ecological setting and context for mosquito control in wetlands, present pertinent information on wetlands mosquitoes, review the mosquito abatement options available for current wetlands managers and mosquito control professionals, and outline some necessary considerations when devising mosquito control strategies. Although the emphasis is on North American wetlands, most of the material is applicable to wetlands everywhere.

Gabrielle E. Sakolsky-Hoopes

2012-12-01

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Entomopathogenic fungi for mosquito control: A review  

Directory of Open Access Journals (Sweden)

Full Text Available Fungal diseases in insects are common and widespread and can decimate their populations in spectacular epizootics. Virtually all insect orders are susceptible to fungal diseases, including Dipterans. Fungal pathogens such as Lagenidium, Coelomomyces and Culicinomyces are known to affect mosquito populations, and have been studied extensively. There are, however, many other fungi that infect and kill mosquitoes at the larval and/or adult stage. The discovery, in 1977, of the selective mosquito-pathogenic bacterium Bacillus thuringiensis Berliner israelensis (Bti curtailed widespread interest in the search for other suitable biological control agents. In recent years interest in mosquito-killing fungi is reviving, mainly due to continuous and increasing levels of insecticide resistance and increasing global risk of mosquito-borne diseases. This review presents an update of published data on mosquito-pathogenic fungi and mosquito-pathogen interactions, covering 13 different fungal genera. Notwithstanding the potential of many fungi as mosquito control agents, only a handful have been commercialized and are marketed for use in abatement programs. We argue that entomopathogenic fungi, both new and existing ones with renewed/improved efficacies may contribute to an expansion of the limited arsenal of effective mosquito control tools, and that they may contribute in a significant and sustainable manner to the control of vector-borne diseases such as malaria, dengue and filariasis.

Ernst-Jan Scholte

2004-06-01

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Aquatic insect predators and mosquito control.  

Science.gov (United States)

Mosquitoes are serious biting pests and obligate vectors of many vertebrate pathogens. Their immature larval and pupal life stages are a common feature in most tropical and many temperate water bodies and often form a significant proportion of the biomass. Control strategies rely primarily on the use of larvicides and environmental modification to reduce recruitment and adulticides during periods of disease transmission. Larvicides are usually chemical but can involve biological toxins, agents or organisms. The use of insect predators in mosquito control has been exploited in a limited fashion and there is much room for further investigation and implementation. Insects that are recognized as having predatorial capacity with regard to mosquito prey have been identified in the Orders Odonata, Coleoptera, Diptera (primarily aquatic predators), and Hemiptera (primarily surface predators). Although their capacity is affected by certain biological and physical factors, they could play a major role in mosquito control. Furthermore, better understanding for the mosquitoes-predators relationship(s) could probably lead to satisfactory reduction of mosquito-borne diseases by utilizing either these predators in control programs, for instance biological and/or integrated control, or their kairomones as mosquitoes' ovipoisting repellents. This review covers the predation of different insect species on mosquito larvae, predator-prey-habitat relationships, co-habitation developmental issues, survival and abundance, oviposition avoidance, predatorial capacity and integrated vector control. PMID:20237438

Shaalan, Essam Abdel-Salam; Canyon, Deon V

2009-12-01

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Genetic control of mosquitoes: population suppression strategies.  

Science.gov (United States)

Over the last two decades, morbidity and mortality from malaria and dengue fever among other pathogens are an increasing Public Health problem. The increase in the geographic distribution of vectors is accompanied by the emergence of viruses and diseases in new areas. There are insufficient specific therapeutic drugs available and there are no reliable vaccines for malaria or dengue, although some progress has been achieved, there is still a long way between its development and actual field use. Most mosquito control measures have failed to achieve their goals, mostly because of the mosquito's great reproductive capacity and genomic flexibility. Chemical control is increasingly restricted due to potential human toxicity, mortality in no target organisms, insecticide resistance, and other environmental impacts. Other strategies for mosquito control are desperately needed. The Sterile Insect Technique (SIT) is a species-specific and environmentally benign method for insect population suppression, it is based on mass rearing, radiation mediated sterilization, and release of a large number of male insects. Releasing of Insects carrying a dominant lethal gene (RIDL) offers a solution to many of the drawbacks of traditional SIT that have limited its application in mosquitoes while maintaining its environmentally friendly and species-specific utility. The self-limiting nature of sterile mosquitoes tends to make the issues related to field use of these somewhat less challenging than for self-spreading systems characteristic of population replacement strategies. They also are closer to field use, so might be appropriate to consider first. The prospect of genetic control methods against mosquito vectored human diseases is rapidly becoming a reality, many decisions will need to be made on a national, regional and international level regarding the biosafety, social, cultural and ethical aspects of the use and deployment of these vector control methods. PMID:22983293

Wilke, André Barretto Bruno; Marrelli, Mauro Toledo

2012-01-01

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Ecology of vector mosquitoes in Sri Lanka--suggestions for future mosquito control in rice ecosystems.  

Science.gov (United States)

Mosquito-borne diseases are a major public health threat in Asia. To explore effective mosquito control strategies in rice ecosystems from the ecological point of view, we carried out ecological analyses of vector mosquitoes in Sri Lanka. During the 18-month study period, 14 Anopheles, 11 Culex, 5 Aedes, 2 Mansonia, and 1 Armigeres species were collected, most of which are disease vectors for malaria, filariasis, Japanese encephalitis, or dengue in Sri Lanka and elsewhere in Asia. The density and occurrence of Anopheles and Culex species were the highest in seepage pools and paddy fields, where the majority of niche overlaps between larval mosquito and aquatic insect species were observed. All 7 aquatic insect species, which are larval mosquito predators, overlapped their niche with both Anopheles and Culex larvae. This suggests that conserving these aquatic insect species could be effective in controlling mosquito vectors in the study site. Correlations between several climatic factors and mosquito density were also analyzed, and weather conditions, including higher temperature, lower relative humidity, and higher wind velocity, were found to affect mosquito oviposition, propagation, and survival. These findings deepen our understanding of mosquito ecology and will strengthen future mosquito control strategies in rice ecosystems in Asia. PMID:17883002

Yasuoka, Junko; Levins, Richard

2007-07-01

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Control of mosquitoes by the sterile male technique  

International Nuclear Information System (INIS)

Field tests on the applicability of SIT to mosquito control have been conducted since the late 1950s. Early field experiments were conducted by releasing radiation-sterilized males. Methods of chemically sterilizing mosquitoes were also developed. Genetically altered strains which are partially sterile were also developed, studied and then used in field experiments. The earliest release experiments with mosquitoes were unsuccessful in introducing sterility into natural populations or reducing insect density, but identified problems and developed methodology. A summary of the releases conducted since the 1950s is given as background and then recent tests are reviewed in more detail where population control was achieved. The advances made in understanding the dynamics of field populations of mosquitoes when subjected to SIT are also reviewed. The problems associated with SIT for mosquito control - absolute density, growth rate, migration and others - are also discussed. (author)

1981-07-03

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Spraying quality assessment of sprayers devoted to mosquito control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mosquito control in France is achieved through the spraying in natural areas including water surfaces a wide range of sprayers with a combination of terrestrial and aerial applications. Classical evaluation of the application is mainly related to biological efficacy in terms of mosquito (larvae or adults) mortality [1]. The IMCM Life + project encompasses the evaluation of the spraying quality of terrestrial sprayers for both larvicide and adulticide applications by testing sprayer performanc...

Rudnicki, V.; Douzals, J. P.; Tolosa, M.; Sidos, N.; Cotteux, E.

2012-01-01

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Control of mosquito breeding through Gambusia affinis in rice fields.  

Science.gov (United States)

Studies on mosquito breeding and its control through Gambusia affinis in nursery and paddy fields after transplantation of seedlings were carried out during June to October 1991 in about 10 ha rice field area. Six anopheline species, viz. An. culicifacies, An. annularis, An. subpictus, An. nigerrimus, An. barbirostris and An. aconitus, and four culicine species, viz. Cx. tritaeniorhynchus, Cx. bitaeniorhynchus, Cx. quinquefasciatus, and Aedes sp. could be identified. These were found breeding in rice fields with fluctuations in their percentage composition, exhibiting species succession in different months. G. affinis survived well in submerged rice fields and provided 87.8% mosquito larval control. In rice fields which exhibited intermittent drying up leading to formation of pools, puddles etc., moderate larval control was achieved. However, in nursery rice fields, this method was not applicable. Mosquito larval control through larvivorous fish in rice fields can be achieved but the method has limitations. PMID:8405595

Prasad, H; Prasad, R N; Haq, S

1993-06-01

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Controle de vetores utilizando mosquitos geneticamente modificados / Control of vector populations using genetically modified mosquitoes / Control de vectores utilizando mosquitos genéticamente modificados  

Scientific Electronic Library Online (English)

Full Text Available SciELO Public Health | Language: Portuguese Abstract in portuguese Formas químicas de controle de mosquitos vetores são ineficazes, levando ao desenvolvimento de novas estratégias. Assim, foi realizada revisão das estratégias de controle genético de populações de mosquitos vetores baseada na técnica do inseto estéril. Uma delas consiste na liberação de machos ester [...] ilizados por radiação, a outra, na integração de um gene letal dominante associado a um promotor específico de fêmeas imaturas. Entre as vantagens sobre outras técnicas biológicas e químicas de controle de vetores estão: alta especificidade, não prejudicial ao meio ambiente, baixo custo de produção e alta eficácia. O uso desta técnica de modificação genética pode vir a ser uma importante ferramenta do manejo integrado de vetores. Abstract in spanish Formas químicas de control de mosquitos vectores son ineficaces, llevando al desarrollo de nuevas estrategias. Así, fue realizada revisión de las estrategias de control genético de poblaciones de mosquitos vectores basada en la técnica del insecto estéril. Una de ellas consiste en la liberación de m [...] achos esterilizados por radiación, la otra, en la integración de un gen letal dominante asociado a un promotor específico de hembras inmaduras. Entre las ventajas sobre otras técnicas biológicas y químicas de control de vectores están: la alta especificidad, no prejudicial al ambiente, bajo costo de producción y alta eficiencia. El uso de esta técnica de modificación genética puede ser una importante herramienta del manejo integrado de vectores. Abstract in english The ineffectiveness of current strategies for chemical control of mosquito vectors raises the need for developing novel approaches. Thus, we carried out a literature review of strategies for genetic control of mosquito populations based on the sterile insect technique. One of these strategies consis [...] ts of releasing radiation-sterilized males into the population; another, of integrating a dominant lethal gene under the control of a specific promoter into immature females. Advantages of these approaches over other biological and chemical control strategies include: highly species-specific, environmentally safety, low production cost, and high efficacy. The use of this genetic modification technique will constitute an important tool for integrated vector management.

André Barreto Bruno, Wilke; Almério de Castro, Gomes; Delsio, Natal; Mauro Toledo, Marrelli.

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Controle de vetores utilizando mosquitos geneticamente modificados / Control of vector populations using genetically modified mosquitoes / Control de vectores utilizando mosquitos genéticamente modificados  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Formas químicas de controle de mosquitos vetores são ineficazes, levando ao desenvolvimento de novas estratégias. Assim, foi realizada revisão das estratégias de controle genético de populações de mosquitos vetores baseada na técnica do inseto estéril. Uma delas consiste na liberação de machos ester [...] ilizados por radiação, a outra, na integração de um gene letal dominante associado a um promotor específico de fêmeas imaturas. Entre as vantagens sobre outras técnicas biológicas e químicas de controle de vetores estão: alta especificidade, não prejudicial ao meio ambiente, baixo custo de produção e alta eficácia. O uso desta técnica de modificação genética pode vir a ser uma importante ferramenta do manejo integrado de vetores. Abstract in spanish Formas químicas de control de mosquitos vectores son ineficaces, llevando al desarrollo de nuevas estrategias. Así, fue realizada revisión de las estrategias de control genético de poblaciones de mosquitos vectores basada en la técnica del insecto estéril. Una de ellas consiste en la liberación de m [...] achos esterilizados por radiación, la otra, en la integración de un gen letal dominante asociado a un promotor específico de hembras inmaduras. Entre las ventajas sobre otras técnicas biológicas y químicas de control de vectores están: la alta especificidad, no prejudicial al ambiente, bajo costo de producción y alta eficiencia. El uso de esta técnica de modificación genética puede ser una importante herramienta del manejo integrado de vectores. Abstract in english The ineffectiveness of current strategies for chemical control of mosquito vectors raises the need for developing novel approaches. Thus, we carried out a literature review of strategies for genetic control of mosquito populations based on the sterile insect technique. One of these strategies consis [...] ts of releasing radiation-sterilized males into the population; another, of integrating a dominant lethal gene under the control of a specific promoter into immature females. Advantages of these approaches over other biological and chemical control strategies include: highly species-specific, environmentally safety, low production cost, and high efficacy. The use of this genetic modification technique will constitute an important tool for integrated vector management.

André Barreto Bruno, Wilke; Almério de Castro, Gomes; Delsio, Natal; Mauro Toledo, Marrelli.

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Controle de vetores utilizando mosquitos geneticamente modificados Control de vectores utilizando mosquitos genéticamente modificados Control of vector populations using genetically modified mosquitoes  

Directory of Open Access Journals (Sweden)

Full Text Available Formas químicas de controle de mosquitos vetores são ineficazes, levando ao desenvolvimento de novas estratégias. Assim, foi realizada revisão das estratégias de controle genético de populações de mosquitos vetores baseada na técnica do inseto estéril. Uma delas consiste na liberação de machos esterilizados por radiação, a outra, na integração de um gene letal dominante associado a um promotor específico de fêmeas imaturas. Entre as vantagens sobre outras técnicas biológicas e químicas de controle de vetores estão: alta especificidade, não prejudicial ao meio ambiente, baixo custo de produção e alta eficácia. O uso desta técnica de modificação genética pode vir a ser uma importante ferramenta do manejo integrado de vetores.Formas químicas de control de mosquitos vectores son ineficaces, llevando al desarrollo de nuevas estrategias. Así, fue realizada revisión de las estrategias de control genético de poblaciones de mosquitos vectores basada en la técnica del insecto estéril. Una de ellas consiste en la liberación de machos esterilizados por radiación, la otra, en la integración de un gen letal dominante asociado a un promotor específico de hembras inmaduras. Entre las ventajas sobre otras técnicas biológicas y químicas de control de vectores están: la alta especificidad, no prejudicial al ambiente, bajo costo de producción y alta eficiencia. El uso de esta técnica de modificación genética puede ser una importante herramienta del manejo integrado de vectores.The ineffectiveness of current strategies for chemical control of mosquito vectors raises the need for developing novel approaches. Thus, we carried out a literature review of strategies for genetic control of mosquito populations based on the sterile insect technique. One of these strategies consists of releasing radiation-sterilized males into the population; another, of integrating a dominant lethal gene under the control of a specific promoter into immature females. Advantages of these approaches over other biological and chemical control strategies include: highly species-specific, environmentally safety, low production cost, and high efficacy. The use of this genetic modification technique will constitute an important tool for integrated vector management.

André Barreto Bruno Wilke

2009-10-01

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Production of wetland Chironmidae (Diptera) and the effects of using Bacillus thuringiensis israelensis for mosquito control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Massive mosquito nuisance problems, caused by the flood-water mosquito Aedes sticticus, occur after floods in the flood plains of the River Dalälven, central Sweden. Since 2002, the biological mosquito larvicide Bacillus thuringiensis var. israelensis (Bti) has been used to control these mosquitoes. Here, we report results from the first six years of monitoring Chironomidae, the most susceptible non-target organisms, in three wetlands with Bti-treatment against mosquitoes and in three wetlan...

Lundstro?m, J. O.; Scha?fer, M. L.; Petersson, E.; Persson Vinnersten, T. Z.; Landin, Jan; Brodin, Y.

2010-01-01

18

Novel Selective and Irreversible Mosquito Acetylcholinesterase Inhibitors for Controlling Malaria and Other Mosquito-Borne Diseases  

Science.gov (United States)

We reported previously that insect acetylcholinesterases (AChEs) could be selectively and irreversibly inhibited by methanethiosulfonates presumably through conjugation to an insect-specific cysteine in these enzymes. However, no direct proof for the conjugation has been published to date, and doubts remain about whether such cysteine-targeting inhibitors have desirable kinetic properties for insecticide use. Here we report mass spectrometric proof of the conjugation and new chemicals that irreversibly inhibited African malaria mosquito AChE with bimolecular inhibition rate constants (kinact/KI) of 3,604-458,597 M-1sec-1 but spared human AChE. In comparison, the insecticide paraoxon irreversibly inhibited mosquito and human AChEs with kinact/KI values of 1,915 and 1,507 M-1sec-1, respectively, under the same assay conditions. These results further support our hypothesis that the insect-specific AChE cysteine is a unique and unexplored target to develop new insecticides with reduced insecticide resistance and low toxicity to mammals, fish, and birds for the control of mosquito-borne diseases.

Dou, Dengfeng; Park, Jewn Giew; Rana, Sandeep; Madden, Benjamin J.; Jiang, Haobo; Pang, Yuan-Ping

2013-01-01

19

Environmental Factors Affecting Efficacy of Bifenthrin-Treated Vegetation for Mosquito Control.  

Science.gov (United States)

The use of pesticide-treated vegetation as a barrier for control of nuisance and disease-bearing mosquitoes has become an option for mosquito management for home owners and public health and mosquito control professionals. Potted wax myrtle and azalea pla...

D. L. Kline S. A. Allan T. Walker

2009-01-01

20

Genetic methods for control of mosquitoes and biting flies  

International Nuclear Information System (INIS)

The earliest research efforts on using genetic methods for the control of mosquitoes and biting flies concentrated on the evaluation of the sterile insect technique (SIT). Several successful, but generally small scale, research efforts with mosquitoes clearly documented that either chemosterilized or radiation sterilized males were effective in causing a level of genetic load that would be sufficient for the reduction or eradication of natural populations of several species. Genetic sexing strains of several species of mosquitoes have been assembled, and this aspect of breeding specialty strains is not a limiting factor in the implementation of SIT. In the largest field experiment, conducted with Anopheles albimanus in El Salvador during the 1970s, a genetic sexing strain was used operationally in a factory that produced one million sterile males per day over a one year period. Technical problems that would require extensive research of a practical nature before the implementation of SIT for mosquito control involve primarily better means for the rearing, sterilization and distribution of the insects. A successful experiment was conducted to eliminate the stable fly on the island of St. Croix, the United States Virgin Islands, and since this work in the 1970s, genetic sexing strains have been developed. A considerable amount of effort was expended on the synthesis of chromosome aberrations for the control of mosquitoes. Although the results of experimental trials indicated that aberration bearing insects could effectively inject a genetic load into the natural population, no large scale tests have ever been conducted to evaluate fully the real effectiveness of induced chromosomal aberrations. More recently, most of the research work in genetic control has been aimed at the use of recombinant DNA techniques for the development of new technology. All of these topics and an assessment of their value are discussed. (author). 30 refs

1987-11-16

 
 
 
 
21

Tidal circulation alteration for salt marsh mosquito control  

Science.gov (United States)

Mosquito control ditches designed to increase tidal circulation are widely used as a physical control alternative to insecticidal applications The impact of such ditching on Pacific Coast marshlands was largely unknown before this five-year study of impact in two types of San Francisco Bay salt marshes, a Salicornia virginica (pickleweed) monoculure and a mixed vegetation marsh Results of our studies suggest that ditches cause less environmental disturbance than insecticidal applications The article describes the following environmental consequences of ditching for mosquito control: increased tidal flushing of soils occurs adjacent to ditches compared with that in the open marsh, thereby reducing ground water and soil surface salinities and water table height; primary productivity of S. virginica, as determined by both the harvest method and infrared photographic analysis, is higher directly adjacent to ditches than in the open marsh, distribution of selected arthropod populations is similar at ditches and natural channels, although arthropod community response differs seasonally; aquatic invertebrate biomass is similar within ditched and natural ponds, but diversity is lower in ditched habitats, ditching increases fish diversity and density by improving fish access from tidal channels; ditches provide additional salt marsh song sparrow habitat, although ditches are less preferred than natural channels or sloughs. Management criteria can be used to design ditches that provide effective mosquito control and reduced environmental impact

Resh, Vincent H.; Balling, Steven S.

1983-01-01

22

Late-acting dominant lethal genetic systems and mosquito control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Reduction or elimination of vector populations will tend to reduce or eliminate transmission of vector-borne diseases. One potential method for environmentally-friendly, species-specific population control is the Sterile Insect Technique (SIT). SIT has not been widely used against insect disease vectors such as mosquitoes, in part because of various practical difficulties in rearing, sterilization and distribution. Additionally, vector populations with str...

2007-01-01

23

Harnessing mosquito-Wolbachia symbiosis for vector and disease control.  

Science.gov (United States)

Mosquito species, members of the genera Aedes, Anopheles and Culex, are the major vectors of human pathogens including protozoa (Plasmodium sp.), filariae and of a variety of viruses (causing dengue, chikungunya, yellow fever, West Nile). There is lack of efficient methods and tools to treat many of the diseases caused by these major human pathogens, since no efficient vaccines or drugs are available; even in malaria where insecticide use and drug therapies have reduced incidence, 219 million cases still occurred in 2010. Therefore efforts are currently focused on the control of vector populations. Insecticides alone are insufficient to control mosquito populations since reduced susceptibility and even resistance is being observed more and more frequently. There is also increased concern about the toxic effects of insecticides on non-target (even beneficial) insect populations, on humans and the environment. During recent years, the role of symbionts in the biology, ecology and evolution of insect species has been well-documented and has led to suggestions that they could potentially be used as tools to control pests and therefore diseases. Wolbachia is perhaps the most renowned insect symbiont, mainly due to its ability to manipulate insect reproduction and to interfere with major human pathogens thus providing new avenues for pest control. We herein present recent achievements in the field of mosquito-Wolbachia symbiosis with an emphasis on Aedes albopictus. We also discuss how Wolbachia symbiosis can be harnessed for vector control as well as the potential to combine the sterile insect technique and Wolbachia-based approaches for the enhancement of population suppression programs. PMID:24252486

Bourtzis, Kostas; Dobson, Stephen L; Xi, Zhiyong; Rasgon, Jason L; Calvitti, Maurizio; Moreira, Luciano A; Bossin, Hervé C; Moretti, Riccardo; Baton, Luke Anthony; Hughes, Grant L; Mavingui, Patrick; Gilles, Jeremie R L

2014-04-01

24

Perspectives of people in Mali toward genetically-modified mosquitoes for malaria control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Genetically-modified (GM) mosquitoes have been proposed as part of an integrated vector control strategy for malaria control. Public acceptance is essential prior to field trials, particularly since mosquitoes are a vector of human disease and genetically modified organisms (GMOs) face strong scepticism in developed and developing nations. Despite this, in sub-Saharan Africa, where the GM mosquito effort is primarily directed, very little data is available...

Marshall John M; Touré Mahamoudou B; Traore Mohamed M; Famenini Shannon; Taylor Charles E

2010-01-01

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Aerial and Tidal Transport of Mosquito Control Pesticides into the Florida Keys National Marine Sanctuary  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This project was undertaken as the initial monitoring program to determine if mosquito adulticides applied along the Florida Keys cause adverse ecological effects in the Florida Keys National Marine Sanctuary (FKNMS).The study monitored the distribution and persistence of two mosquito adulticides,permethrin and dibrom (naled),during three separate routine applications by the Florida Keys Mosquito Control District.The approach was to determine if toxic concentrations of the pesticides entered ...

Pierce, R. H.; Henry, M. S.; Blum, T. C.; Mueller, E. M.

2005-01-01

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Malaria mosquito control using edible fish in western Kenya: preliminary findings of a controlled study  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Biological control methods are once again being given much research focus for malaria vector control. This is largely due to the emerging threat of strong resistance to pesticides. Larvivorous fish have been used for over 100 years in mosquito control and many species have proved effective. In the western Kenyan highlands the larvivorous fish Oreochromis niloticus L. (Perciformes: Cichlidae (formerly Tilapia nilotica is commonly farmed and eaten but has not been previously tested in the field for malaria mosquito control. Methods This fish was introduced into abandoned fishponds at an altitude of 1,880 m and the effect measured over six months on the numbers of mosquito immatures. For comparison an untreated control pond was used. During this time, all ponds were regularly cleared of emergent vegetation and fish re-stocking was not needed. Significant autocorrelation was removed from the time series data, and t-tests were used to investigate within a pond and within a mosquito type any differences before and after the introduction of O. niloticus. Mulla's formula was also used on the raw data to calculate the percentage reduction of the mosquito larvae. Results After O. niloticus introduction, mosquito densities immediately dropped in the treated ponds but increased in the control pond. This increase was apparently due to climatic factors. Mulla's formula was applied which corrects for that natural tendency to increase. The results showed that after 15 weeks the fish caused a more than 94% reduction in both Anopheles gambiae s.l. and Anopheles funestus (Diptera: Culicidae in the treated ponds, and more than 75% reduction in culicine mosquitoes. There was a highly significantly reduction in A. gambiae s.l. numbers when compared to pre-treatment levels. Conclusion This study reports the first field trial data on O. niloticus for malaria mosquito control and shows that this species, already a popular food fish in western Kenya, is an apparently sustainable mosquito control tool which also offers a source of protein and income to people in rural areas. There should be no problem with acceptance of this malaria control method since the local communities already farm this fish species.

Omlin Francois X

2007-08-01

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EFFICACY OF AGERATUM CONYZOIDES AGAINST THE CONTROL OF MOSQUITOES  

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Full Text Available Mosquitoes transmit serious human diseases causing millions of deaths every year. Phytochemistry has proven that there are potential mosquito control agents and also alternatives to synthetic insecticides. The present paper reports Ageratum conyzoides commonly known as Kubhi in Hindi of family Astereacae. The plant after proper identification was collected shade dried and powdered to the fine mesh size. 5 different concentrations were used against IInd and IVth instar of Anapheles stephensi. Larvicidal and growth inhibitory activity of Ageratum conyzoides exhibited in the II and IVth instar larvae of the Anapheles stephensi. After 24 hours, LC50 value was determined using probit analysis method. It was notice that the LC50 value for IInd and IVth instar larvae were 238.65 and 228.54 ppm respectively. The result indicate that fourth instar larvae are more susceptible then second instar larvae .the result obtained suggest that bioactive compound of Ageratum conyzoides could be used in the search for new larvicidal compound of plant origin.

Neetu Arya et al.

2011-12-01

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Monitoring malaria vector control interventions: effectiveness of five different adult mosquito sampling methods.  

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Long-term success of ongoing malaria control efforts based on mosquito bed nets (long-lasting insecticidal net) and indoor residual spraying is dependent on continuous monitoring of mosquito vectors, and thus on effective mosquito sampling tools. The objective of our study was to identify the most efficient mosquito sampling tool(s) for routine vector surveillance for malaria and lymphatic filariasis transmission in coastal Kenya. We evaluated relative efficacy of five collection methods--light traps associated with a person sleeping under a net, pyrethrum spray catches, Prokopack aspirator, clay pots, and urine-baited traps--in four villages representing three ecological settings along the south coast of Kenya. Of the five methods, light traps were the most efficient for collecting female Anopheles gambiae s.l. (Giles) (Diptera: Culicidae) and Anopheles funestus (Giles) (Diptera: Culicidae) mosquitoes, whereas the Prokopack aspirator was most efficient in collecting Culex quinquefasciatus (Say) (Diptera: Culicidae) and other culicines. With the low vector densities here, and across much of sub-Saharan Africa, wherever malaria interventions, long-lasting insecticidal nets, and/or indoor residual spraying are in place, the use of a single mosquito collection method will not be sufficient to achieve a representative sample of mosquito population structure. Light traps will remain a relevant tool for host-seeking mosquitoes, especially in the absence of human landing catches. For a fair representation of the indoor mosquito population, light traps will have to be supplemented with aspirator use, which has potential for routine monitoring of indoor resting mosquitoes, and can substitute the more labor-intensive and intrusive pyrethrum spray catches. There are still no sufficiently efficient mosquito collection methods for sampling outdoor mosquitoes, particularly those that are bloodfed. PMID:24180120

Onyango, Shirley A; Kitron, Uriel; Mungai, Peter; Muchiri, Eric M; Kokwaro, Elizabeth; King, Charles H; Mutuku, Francis M

2013-09-01

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Late-acting dominant lethal genetic systems and mosquito control  

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Full Text Available Abstract Background Reduction or elimination of vector populations will tend to reduce or eliminate transmission of vector-borne diseases. One potential method for environmentally-friendly, species-specific population control is the Sterile Insect Technique (SIT. SIT has not been widely used against insect disease vectors such as mosquitoes, in part because of various practical difficulties in rearing, sterilization and distribution. Additionally, vector populations with strong density-dependent effects will tend to be resistant to SIT-based control as the population-reducing effect of induced sterility will tend to be offset by reduced density-dependent mortality. Results We investigated by mathematical modeling the effect of manipulating the stage of development at which death occurs (lethal phase in an SIT program against a density-dependence-limited insect population. We found late-acting lethality to be considerably more effective than early-acting lethality. No such strains of a vector insect have been described, so as a proof-of-principle we constructed a strain of the principal vector of the dengue and yellow fever viruses, Aedes (Stegomyia aegypti, with the necessary properties of dominant, repressible, highly penetrant, late-acting lethality. Conclusion Conventional SIT induces early-acting (embryonic lethality, but genetic methods potentially allow the lethal phase to be tailored to the program. For insects with strong density-dependence, we show that lethality after the density-dependent phase would be a considerable improvement over conventional methods. For density-dependent parameters estimated from field data for Aedes aegypti, the critical release ratio for population elimination is modeled to be 27% to 540% greater for early-acting rather than late-acting lethality. Our success in developing a mosquito strain with the key features that the modeling indicated were desirable demonstrates the feasibility of this approach for improved SIT for disease control.

Scaife Sarah

2007-03-01

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Simulations to compare efficacies of tetravalent dengue vaccines and mosquito vector control.  

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SUMMARY Infection with dengue, the most prevalent mosquito-borne virus, manifests as dengue fever (DF) or the more fatal dengue haemorrhagic fever (DHF). DHF occurs mainly when an individual who has acquired antibodies to one serotype is inoculated with another serotype. It was reported that mosquito control may have increased the incidence of DF and DHF due to age-dependency in manifesting these illnesses or an immunological mechanism. Tetravalent dengue vaccine is currently being tested in clinical trials. However, seroconversions to all four serotypes were achieved only after three doses. Therefore, vaccines may predispose vaccinees to the risk of developing DHF in future infections. This study employed an individual-based computer simulation, to emulate mosquito control and vaccination, incorporating seroconversion rates reported from actual clinical trials. It was found that mosquito control alone would have increased incidence of DF and DHF in areas of high mosquito density. A vaccination programme with very high coverage, even with a vaccine of suboptimal seroconversion rates, attenuated possible surges in the incidence of DF and DHF which would have been caused by insufficient reduction in mosquito abundance. DHF cases attributable to vaccine-derived enhancement were fewer than DHF cases prevented by a vaccine with considerably high (although not perfect) seroconversion rates. These predictions may justify vaccination programmes, at least in areas of high mosquito abundance. In such areas, mosquito control programmes should be conducted only after the vaccination programme with a high coverage has been initiated. PMID:23925059

Thavara, U; Tawatsin, A; Nagao, Y

2014-06-01

31

Method for Dispensing Planaria (Dugesia dorotocephala) for Mosquito Control,  

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Predation studies of mosquitoes by the planarian dugesia dorotocephala have since shown that D. dorotocephala is an effective predator on all larval stages of mosquitoes. Densities of 25 planaria/m2 have been cited as sufficient to effect significant cont...

W. M. Darby L. R. Boobar M. R. Sardelis

1988-01-01

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Abundance of water bodies is critical to guide mosquito larval control interventions and predict risk of mosquito-borne diseases  

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Characterization of mosquito breeding habitats is often accomplished with the goal of guiding larval control interventions as well as the goal of identifying areas with higher disease risk. This characterization often relies on statistical measures of association (e.g., regression coefficients) between covariates and presence/absence or abundance of larva. Here we contend that these measures of association are not enough; researchers should also study the spatial and temporal distribution of ...

Valle, Denis; Zaitchik, Benjamin; Feingold, Beth; Spangler, Keith; Pan, William

2013-01-01

33

Mathematical Modeling of Sterile Insect Technology for Control of Anopheles Mosquito  

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Sterile Insect Technology (SIT) is a nonpolluting method of insect control that relies on the release of sterile males. We study the effectiveness of the application of SIT for control of Anopheles mosquito via mathematical modeling. The theoretical analysis of the mathematical model as a dynamical system leads to the formulation of possible strategies for control of the Anopheles mosquito, also illustrated by numerical simulations.

Anguelov, R.; Dumont, Y.; Lubuma, J.

2011-11-01

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The use of bacterial larvicides in mosquito and black fly control programmes in Brazil  

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Bacillus spp. based larvides are increasingly replacing, with numerous advantages, chemical insecticides in programmes for controlling black fly and mosquito populations. Brazil was among the pioneers in adopting Bacillus thuringiensis israelensis (B.t.i) to control black flies. However, the major current mosquito control programme in Brazil, the Programme for Eradication of Aedes aegypti launched in 1997, only recently decided to replace temephos by B.t.i based larvicides, in the State of Ri...

2000-01-01

35

Efficacy of methoprene for mosquito control in storm water catch basins  

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This study evaluated the efficacy of methoprene, a widely used juvenile hormone mimic, formulated as 30-day slow release Altosid? pellets, at controlling mosquitoes in underground storm water drainage catch basins. Data from applications to ?-sized cement catch basins in the laboratory, field observations from treated and untreated basins, and an experiment that confined mosquito larvae in floating emergence jars in catch basins showed that methoprene effectively controlled mosquitoes for a month under field conditions and substantially longer under laboratory conditions when applied at a dose of 3.5 g pellets per average-sized catch basin.

Butler, M.; LeBrun, R.A.; Ginsberg, H.S.; Gettman, A.D.

2006-01-01

36

Transfer of toxin genes to alternate bacterial hosts for mosquito control  

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Mosquitoes are vector of serious human and animal diseases, such as malaria, dengue, yellow fever, among others. The use of biological control agents has provide an environmentally safe and highly specific alternative to the use of chemical insecticides in the control of vector borne diseases. Bacillus thuringiensis and B. sphaericus produce toxic proteins to mosquito larvae. Great progress has been made on the biochemical and molecular characterization of such proteins and the genes encoding...

Sergio Orduz; Nora Restrepo; Patin?o, Maria M.; William Rojas

1995-01-01

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High-throughput sorting of mosquito larvae for laboratory studies and for future vector control interventions  

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Abstract Background Mosquito transgenesis offers new promises for the genetic control of vector-borne infectious diseases such as malaria and dengue fever. Genetic control strategies require the release of large number of male mosquitoes into field populations, whether they are based on the use of sterile males (sterile insect technique, SIT) or on introducing genetic traits conferring refractoriness to disease transmission (population replacement). However, the current absen...

Marois Eric; Scali Christina; Soichot Julien; Kappler Christine; Levashina Elena A; Catteruccia Flaminia

2012-01-01

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Taking malaria transmission out of the bottle: implications of mosquito dispersal for vector-control interventions  

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Most malaria transmission models assume enclosed systems of people, parasites, and vectors in which neither emigration nor immigration of mosquitoes is considered. This simplification has facilitated insightful analyses but has substantial limitations for evaluating control measures in the field. Here we show that mosquito dispersal can confound conventional approaches to evaluating malaria vector-control interventions, and explore this association with a model of two villages between which m...

2003-01-01

39

Crustacean biodiversity as an important factor for mosquito larval control.  

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Newly established ponds, which are highly dynamic systems with changing levels of biological interactions among species, are common larval mosquito habitats. We investigated the impact of crustacean abundance and taxa diversity on mosquito oviposition and larval development. The effects of the biological larvicide Bacillus thuringiensis israelensis (Bti) on mosquito larvae were monitored according to fluctuations in crustacean communities. Populations of the mosquito Culex pipiens colonized artificial ponds that contained crustacean communities at different time points of colonization by crustaceans: 1) 'no colonization' (no crustaceans), 2) 'simultaneous colonization' by crustaceans and mosquitoes, and 3) 'head-start colonization' by crustaceans (preceding colonization by mosquitoes). All types of ponds were treated with three concentrations of Bti (10, 100, or 1,000 µg/liter). Colonization of all ponds by Cx. pipiens (in terms of oviposition, larval abundance, and larval development) decreased significantly with increasing diversity of crustacean taxa. The total abundance of crustaceans had a minor effect on colonization by Cx. pipiens. The presence of crustaceans increased the sensitivity of Cx. pipiens larvae to Bti treatment by a factor of 10 and delayed the time of recolonization. This effect of Bti was relevant in the short term. In the long term, the presence of Cx. pipiens was determined by crustacean biodiversity. PMID:24581370

Kroeger, Iris; Duquesne, Sabine; Liess, Matthias

2013-12-01

40

Mosquitoes Associated with Ditch-Plugged and Control Tidal Salt Marshes on the Delmarva Peninsula  

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Full Text Available A study was conducted during the summer of 2009 (from July to September to characterize mosquito communities among different habitats in five historically ditched tidal salt marshes and three adjacent wooded areas in the E.A. Vaughn Wetland Management Area on the Maryland Delmarva Peninsula, USA. Study marshes are characteristic of Atlantic coastal salt marshes that had undergone grid ditching from the 1930s to 1950s. In the autumn of 2008 (October and November ditches were plugged near their outlets in two (‘experimental’ marshes with the aim to restore their natural tidal hydrology. The three other marshes were not plugged. Marshes were sampled from July to September in 2009 by using standard dip count method. A total of 2,457 mosquito larvae representing six species were collected on 15.4% (86/557 of all sample occasions and 399 adults representing four mosquito species were collected from landing counts. Aedes sollicitans, Anopheles bradleyi and Culex salinarius were the most common species collected in larval habitats, and Ae. sollicitans was the most common adult collected. Wooded habitats had more total mosquitoes, were also more frequently occupied by mosquitoes and had higher densities of mosquitoes than marsh habitats. Almost all larvae collected from marshes were from one experimental and one control site. The majority of larvae at the control site were Ae. sollicitans in marsh pannes while Cx. salinarius, An. bradleyi, Ae. cantator, and Ae. sollicitans were collected in high numbers from ditches at the experimental site. We found a difference in the proportion of marsh pannes occupied by Ae. sollicitans but not total mosquitoes sampled 4–5 days after spring tide events than on other occasions. Salinity measures of 42 larval habitats showed lower median salinity in mosquito-occupied habitats (11.5 ppt than unoccupied habitats (20.1 ppt, and in habitats in wooded areas followed by ditches and pannes in marsh areas. The results of this study suggest that wooded areas adjacent to salt marshes may be a substantial source of biting adult mosquitoes usually associated with salt marsh habitats and that ditch plugging may alter the productivity of mosquitoes on some marshes. We recommend future studies consider mosquito productivity from habitats surrounding salt marshes, and if assessments of marsh alterations are a goal, compare multiple experimental and control areas before and after treatments to determine if alterations have a consistent impact on regional mosquito production.

Paul T. Leisnham

2011-07-01

 
 
 
 
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High-throughput sorting of mosquito larvae for laboratory studies and for future vector control interventions  

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Full Text Available Abstract Background Mosquito transgenesis offers new promises for the genetic control of vector-borne infectious diseases such as malaria and dengue fever. Genetic control strategies require the release of large number of male mosquitoes into field populations, whether they are based on the use of sterile males (sterile insect technique, SIT or on introducing genetic traits conferring refractoriness to disease transmission (population replacement. However, the current absence of high-throughput techniques for sorting different mosquito populations impairs the application of these control measures. Methods A method was developed to generate large mosquito populations of the desired sex and genotype. This method combines flow cytometry and the use of Anopheles gambiae transgenic lines that differentially express fluorescent markers in males and females. Results Fluorescence-assisted sorting allowed single-step isolation of homozygous transgenic mosquitoes from a mixed population. This method was also used to select wild-type males only with high efficiency and accuracy, a highly desirable tool for genetic control strategies where the release of transgenic individuals may be problematic. Importantly, sorted males showed normal mating ability compared to their unsorted brothers. Conclusions The developed method will greatly facilitate both laboratory studies of mosquito vectorial capacity requiring high-throughput approaches and future field interventions in the fight against infectious disease vectors.

Marois Eric

2012-08-01

42

Control of Anopheles albimanus mosquitos in southern Mexico by spraying their preferred indoor resting sites.  

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The traditional indoor spraying technique to control Anopheles albimanus mosquitos was compared with a selective method that targets their preferred resting sites in coastal villages of southern Mexico. We also determined whether mosquitos changed their preferred resting sites following insecticide applications. In the selective spraying approach, two 1-m wide horizontal swaths of bendiocarb insecticide were applied 0.75-1.75 m from the base of the walls and at 1-m upwards from the base of th...

1995-01-01

43

Laboratory determination of efficacy of a Santalum spicatum extract for mosquito control.  

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The activity of QN50, a sequiterpene alcohol derived from Australian sandalwood (Santalum spicatum), was tested for its effectiveness against larvae of 2 mosquito species (Culex molestus and Aedes camptorhynchus [Diptera: Culicidael), nymphs of 2 species of water boatmen (Micronecta robusta and Agraptocorixa [Hemiptera: Corixidae]), immature Daphnia sp. (Crustacea), and mosquito eggs (Cx. molestus). In a series of laboratory bioassays, field-collected mosquito larvae, eggs, and immature corixids and daphnids were placed in beakers with either QN50, methoprene or source water only (control). The mosquito larvae exposed to QN50 had reduced survivorship and average longevity relative to the control and to methoprene at most concentrations used in this study. The hatching rate of mosquito eggs was unaffected by methoprene or QN50. Corixid nymphs and daphnids experienced high mortality in both methoprene and QN50 relative to the control, but there was no difference in the effect between the compounds. The results of this preliminary study suggest that further research into the mode of action and efficacy of QN50 as a potential alternative to methoprene for mosquito abatement is warranted. PMID:17939511

Spafford, Helen; Jardine, Andrew; Carver, Scott; Tarala, Kate; Van Wees, Mary; Weinstein, Phil

2007-09-01

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Diffusion Model On The Efficacy Of Larvicide In Antilarval Operation Of Mosquito Control  

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Mosquito control is being performed under chemical, biological and genetic and altogether it is called integrated vector control. In developing countries like India, chemical control has been given priority. Chemicals used as adulticide is becoming resistance among mosquitoes compared to larvicide. Further, the destruction of immature (larvae) stages of mosquitoes is as effective as its distribution is limited whereas adult mosquitoes turned to terrestrial mode of life and its distribution is based on its flight range, habitat, aggregation of man and animals. In this research paper, selective spray treatment over larvae of mosquitoes of a semi-infinite pool is analyzed using diffusion model. Spray chemical is conceived to spread on the surface with time and in space. A critical concentration of spray chemical is envisaged for assumed death of mosquito larvae. Diffusion is modeled Fick' law. Spray losses are lumped into a first order term. Analytical solution of the resulting partial differential equation for various values of diffusivity and loss rate constant are plotted and interpreted. The model would be useful to appraise beforehand how far and for how long spray would be effective and how much of spray chemical is required for effectiveness within specified distance and time.

Basker, P.; Kumar, T. Ramesh; Prabu, S. Milton; Hemalatha, S.; Elango, S.; Padmanabhan, P.; Asokan, R.

2008-01-01

45

Perspectives of people in Mali toward genetically-modified mosquitoes for malaria control  

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Full Text Available Abstract Background Genetically-modified (GM mosquitoes have been proposed as part of an integrated vector control strategy for malaria control. Public acceptance is essential prior to field trials, particularly since mosquitoes are a vector of human disease and genetically modified organisms (GMOs face strong scepticism in developed and developing nations. Despite this, in sub-Saharan Africa, where the GM mosquito effort is primarily directed, very little data is available on perspectives to GMOs. Here, results are presented of a qualitative survey of public attitudes to GM mosquitoes for malaria control in rural and urban areas of Mali, West Africa between the months of October 2008 and June 2009. Methods The sample consisted of 80 individuals - 30 living in rural communities, 30 living in urban suburbs of Bamako, and 20 Western-trained and traditional health professionals working in Bamako and Bandiagara. Questions were asked about the cause of malaria, heredity and selective breeding. This led to questions about genetic alterations, and acceptable conditions for a release of pest-resistant GM corn and malaria-refractory GM mosquitoes. Finally, participants were asked about the decision-making process in their community. Interviews were transcribed and responses were categorized according to general themes. Results Most participants cited mosquitoes as one of several causes of malaria. The concept of the gene was not widely understood; however selective breeding was understood, allowing limited communication of the concept of genetic modification. Participants were open to a release of pest-resistant GM corn, often wanting to conduct a trial themselves. The concept of a trial was reapplied to GM mosquitoes, although less frequently. Participants wanted to see evidence that GM mosquitoes can reduce malaria prevalence without negative consequences for human health and the environment. For several participants, a mosquito control programme was preferred; however a transgenic release that satisfied certain requirements was usually acceptable. Conclusions Although there were some dissenters, the majority of participants were pragmatic towards a release of GM mosquitoes. An array of social and cultural issues associated with malaria, mosquitoes and genetic engineering became apparent. If these can be successfully addressed, then social acceptance among the populations surveyed seems promising.

Famenini Shannon

2010-05-01

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Eficacia del control de larvas de mosquitos (Diptera: Culicidae con peces larvívoros Effectiveness of the mosquito larvae control (Diptera: Cullicidae by larvivorous fish  

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Full Text Available OBJETIVO: se realizó un estudio de cohorte en los Consejos Populares de Báez y Guaracabulla, pertenecientes al municipio Placetas, provincia Villa Clara, para determinar la eficacia de 3 especies de peces fluviales: Gambusia punctata Poey, 1854, Gambusia puncticulata Poey, 1854 y Poecilia reticulata Peter, 1895, en el control de larvas de mosquitos en depósitos utilizados por la población para almacenar agua. MÉTODOS: la investigación se inició en el mes de abril de 2006 y culminó en mayo de 2007, se seleccionaron solo los tanques bajos (interior y exterior de las viviendas por ser más factibles de evaluar, se trabajó con una muestra de 1 740 depósitos que se dividieron en 2 grupos, los cuales se evaluaron por espacio de 1 año. RESULTADOS: el riesgo de encontrar focos de mosquitos fue superior en el grupo de depósitos que no estaban expuestos a la presencia de peces, la diferencia de riesgo permitió plantear que por cada 100 depósitos tratados con peces, se logró evitar 8 focos de mosquitos. CONCLUSIONES: los peces larvívoros constituyen una excelente alternativa contra las poblaciones larvales de culícidos en depósitos utilizados por la población para almacenar agua, que resulta un factor de protección ante la incidencia de focos de mosquitos.OBJECTIVE: a cohort study was conducted in People´s councils in Báez and Guaracabulla located in Placetas municipality, Villa Clara province, for the purpose of determining the effectiveness of three river fish called Gambusia punctata Poey, 1854, Gambusia puncticulata Poey, 1854 y Poecilia reticulata Peter, 1895 in the control of mosquito larvae inside water reservoirs used by the population. METHODS: the study began in April 2006 and ended May, 2007; the selected water tanks were placed inside and outside the houses since they were more easy to be evaluated. The sample covered 1 740 tanks divided into 2 groups and evaluated for one year. RESULTS: the risk of finding mosquito foci was higher in the group of reservoirs non-exposed to the action of fish; this difference allowed stating that 8 mosquito foci were prevented per every 100 reservoirs treated with fish. CONCLUSIONS: larvivorous fish are an excellent choice to treat Cullicidae larval populations existing in water tanks and also a protective factor against incidence of mosquito foci.

Rigoberto Fimia Duarte

2009-08-01

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Eficacia del control de larvas de mosquitos (Diptera: Culicidae) con peces larvívoros / Effectiveness of the mosquito larvae control (Diptera: Cullicidae) by larvivorous fish  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish OBJETIVO: se realizó un estudio de cohorte en los Consejos Populares de Báez y Guaracabulla, pertenecientes al municipio Placetas, provincia Villa Clara, para determinar la eficacia de 3 especies de peces fluviales: Gambusia punctata Poey, 1854, Gambusia puncticulata Poey, 1854 y Poecilia reticulata [...] Peter, 1895, en el control de larvas de mosquitos en depósitos utilizados por la población para almacenar agua. MÉTODOS: la investigación se inició en el mes de abril de 2006 y culminó en mayo de 2007, se seleccionaron solo los tanques bajos (interior y exterior de las viviendas) por ser más factibles de evaluar, se trabajó con una muestra de 1 740 depósitos que se dividieron en 2 grupos, los cuales se evaluaron por espacio de 1 año. RESULTADOS: el riesgo de encontrar focos de mosquitos fue superior en el grupo de depósitos que no estaban expuestos a la presencia de peces, la diferencia de riesgo permitió plantear que por cada 100 depósitos tratados con peces, se logró evitar 8 focos de mosquitos. CONCLUSIONES: los peces larvívoros constituyen una excelente alternativa contra las poblaciones larvales de culícidos en depósitos utilizados por la población para almacenar agua, que resulta un factor de protección ante la incidencia de focos de mosquitos. Abstract in english OBJECTIVE: a cohort study was conducted in People´s councils in Báez and Guaracabulla located in Placetas municipality, Villa Clara province, for the purpose of determining the effectiveness of three river fish called Gambusia punctata Poey, 1854, Gambusia puncticulata Poey, 1854 y Poecilia reticula [...] ta Peter, 1895 in the control of mosquito larvae inside water reservoirs used by the population. METHODS: the study began in April 2006 and ended May, 2007; the selected water tanks were placed inside and outside the houses) since they were more easy to be evaluated. The sample covered 1 740 tanks divided into 2 groups and evaluated for one year. RESULTS: the risk of finding mosquito foci was higher in the group of reservoirs non-exposed to the action of fish; this difference allowed stating that 8 mosquito foci were prevented per every 100 reservoirs treated with fish. CONCLUSIONS: larvivorous fish are an excellent choice to treat Cullicidae larval populations existing in water tanks and also a protective factor against incidence of mosquito foci.

Fimia Duarte, Rigoberto; Castillo Cuenca, Julio C; Cepero Rodríguez, Omelio; Corona Santander, Edgar; González González, Ramón.

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The effects of zooprophylaxis and other mosquito control measures against malaria in Nouna, Burkina Faso  

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Full Text Available Abstract Background In the absence of large scale, organized vector control programmes, individual protective measures against mosquitoes are essential for reducing the transmission of diseases like malaria. Knowledge of the types and effectiveness of mosquito control methods used by households can aid in the development and promotion of preventive measures. Methods A matched, population-based case control study was carried out in the semi-urban region of Nouna, Burkina Faso. Surveys and mosquito captures were conducted for each participating household. Data were analysed using conditional logistic regression and Pearson's product-moment correlations. Results In Nouna, Burkina Faso, the main types of reported mosquito control measures used included sleeping under bed nets (insecticide-treated and untreated and burning mosquito coils. Most of the study households kept animals within the compound or house at night. Insecticide house sprays, donkeys, rabbits and pigs were significantly associated with a reduced risk of malaria only in univariate analyses. Conclusion Given the conflicting results of the effects of zooprophylaxis from previous studies, other community-based preventive measures, such as bed nets, coils and insecticide house-spraying, may be of more benefit.

Sié Ali

2009-12-01

49

The use of bacterial larvicides in mosquito and black fly control programmes in Brazil  

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Full Text Available Bacillus spp. based larvides are increasingly replacing, with numerous advantages, chemical insecticides in programmes for controlling black fly and mosquito populations. Brazil was among the pioneers in adopting Bacillus thuringiensis israelensis (B.t.i to control black flies. However, the major current mosquito control programme in Brazil, the Programme for Eradication of Aedes aegypti launched in 1997, only recently decided to replace temephos by B.t.i based larvicides, in the State of Rio de Janeiro. In the last decade, works developed by research groups in Brazilian institutions have generated a significant contribution to this subject through the isolation of B. sphaericus new strains, the development of new products and the implementation of field trials of Bacillus efficacy against mosquito species under different environmental conditions.

Regis Lêda

2000-01-01

50

The use of bacterial larvicides in mosquito and black fly control programmes in Brazil  

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Full Text Available SciELO Brazil | Language: English Abstract in english Bacillus spp. based larvides are increasingly replacing, with numerous advantages, chemical insecticides in programmes for controlling black fly and mosquito populations. Brazil was among the pioneers in adopting Bacillus thuringiensis israelensis (B.t.i) to control black flies. However, the major c [...] urrent mosquito control programme in Brazil, the Programme for Eradication of Aedes aegypti launched in 1997, only recently decided to replace temephos by B.t.i based larvicides, in the State of Rio de Janeiro. In the last decade, works developed by research groups in Brazilian institutions have generated a significant contribution to this subject through the isolation of B. sphaericus new strains, the development of new products and the implementation of field trials of Bacillus efficacy against mosquito species under different environmental conditions.

Lêda, Regis; Sinara B da, Silva; Maria Alice V, Melo-Santos.

51

Recasting the theory of mosquito-borne pathogen transmission dynamics and control.  

Science.gov (United States)

Mosquito-borne diseases pose some of the greatest challenges in public health, especially in tropical and sub-tropical regions of the world. Efforts to control these diseases have been underpinned by a theoretical framework developed for malaria by Ross and Macdonald, including models, metrics for measuring transmission, and theory of control that identifies key vulnerabilities in the transmission cycle. That framework, especially Macdonald's formula for R0 and its entomological derivative, vectorial capacity, are now used to study dynamics and design interventions for many mosquito-borne diseases. A systematic review of 388 models published between 1970 and 2010 found that the vast majority adopted the Ross-Macdonald assumption of homogeneous transmission in a well-mixed population. Studies comparing models and data question these assumptions and point to the capacity to model heterogeneous, focal transmission as the most important but relatively unexplored component in current theory. Fine-scale heterogeneity causes transmission dynamics to be nonlinear, and poses problems for modeling, epidemiology and measurement. Novel mathematical approaches show how heterogeneity arises from the biology and the landscape on which the processes of mosquito biting and pathogen transmission unfold. Emerging theory focuses attention on the ecological and social context for mosquito blood feeding, the movement of both hosts and mosquitoes, and the relevant spatial scales for measuring transmission and for modeling dynamics and control. PMID:24591453

Smith, David L; Perkins, T Alex; Reiner, Robert C; Barker, Christopher M; Niu, Tianchan; Chaves, Luis Fernando; Ellis, Alicia M; George, Dylan B; Le Menach, Arnaud; Pulliam, Juliet R C; Bisanzio, Donal; Buckee, Caroline; Chiyaka, Christinah; Cummings, Derek A T; Garcia, Andres J; Gatton, Michelle L; Gething, Peter W; Hartley, David M; Johnston, Geoffrey; Klein, Eili Y; Michael, Edwin; Lloyd, Alun L; Pigott, David M; Reisen, William K; Ruktanonchai, Nick; Singh, Brajendra K; Stoller, Jeremy; Tatem, Andrew J; Kitron, Uriel; Godfray, H Charles J; Cohen, Justin M; Hay, Simon I; Scott, Thomas W

2014-04-01

52

Recasting the theory of mosquito-borne pathogen transmission dynamics and control  

Science.gov (United States)

Mosquito-borne diseases pose some of the greatest challenges in public health, especially in tropical and sub-tropical regions of the world. Efforts to control these diseases have been underpinned by a theoretical framework developed for malaria by Ross and Macdonald, including models, metrics for measuring transmission, and theory of control that identifies key vulnerabilities in the transmission cycle. That framework, especially Macdonald's formula for R0 and its entomological derivative, vectorial capacity, are now used to study dynamics and design interventions for many mosquito-borne diseases. A systematic review of 388 models published between 1970 and 2010 found that the vast majority adopted the Ross–Macdonald assumption of homogeneous transmission in a well-mixed population. Studies comparing models and data question these assumptions and point to the capacity to model heterogeneous, focal transmission as the most important but relatively unexplored component in current theory. Fine-scale heterogeneity causes transmission dynamics to be nonlinear, and poses problems for modeling, epidemiology and measurement. Novel mathematical approaches show how heterogeneity arises from the biology and the landscape on which the processes of mosquito biting and pathogen transmission unfold. Emerging theory focuses attention on the ecological and social context for mosquito blood feeding, the movement of both hosts and mosquitoes, and the relevant spatial scales for measuring transmission and for modeling dynamics and control.

Smith, David L.; Perkins, T. Alex; Reiner, Robert C.; Barker, Christopher M.; Niu, Tianchan; Chaves, Luis Fernando; Ellis, Alicia M.; George, Dylan B.; Le Menach, Arnaud; Pulliam, Juliet R. C.; Bisanzio, Donal; Buckee, Caroline; Chiyaka, Christinah; Cummings, Derek A. T.; Garcia, Andres J.; Gatton, Michelle L.; Gething, Peter W.; Hartley, David M.; Johnston, Geoffrey; Klein, Eili Y.; Michael, Edwin; Lloyd, Alun L.; Pigott, David M.; Reisen, William K.; Ruktanonchai, Nick; Singh, Brajendra K.; Stoller, Jeremy; Tatem, Andrew J.; Kitron, Uriel; Godfray, H. Charles J.; Cohen, Justin M.; Hay, Simon I.; Scott, Thomas W.

2014-01-01

53

Knowledge of mosquitos in relation to public and domestic control activities in the cities of Dar es Salaam and Tanga.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A study of community awareness of mosquitos and related subjects in the residential areas of two Tanzanian cities (Dar es Salaam and Tanga) showed that residents were well aware of mosquitos. Almost all claimed to use some form of domestic mosquito control product for their personal protection, and many spend a significant portion of the household income on this. The problems of nuisance-biting and malaria transmission are usually not separated and are considered to be the result of poor envi...

Stephens, C.; Masamu, E. T.; Kiama, M. G.; Keto, A. J.; Kinenekejo, M.; Ichimori, K.; Lines, J.

1995-01-01

54

Modelling Aedes aegypti mosquito control via transgenic and sterile insect techniques: endemics and emerging outbreaks.  

Science.gov (United States)

The invasion of pest insects often changes or destroys a native ecosystem, and can result in food shortages and disease endemics. Issues such as the environmental effects of chemical control methods, the economic burden of maintaining control strategies and the risk of pest resistance still remain, and mosquito-borne diseases such as malaria and dengue fever prevail in many countries, infecting over 100 million worldwide in 2010. One environmentally friendly method for mosquito control is the Sterile Insect Technique (SIT). This species-specific method of insect control relies on the mass rearing, sterilization and release of large numbers of sterile insects. An alternative transgenic method is the Release of Insects carrying a Dominant Lethal (RIDL). Our objective is to consider contrasting control strategies for two invasive scenarios via SIT and RIDL: an endemic case and an emerging outbreak. We investigate how the release rate and size of release region influence both the potential for control success and the resources needed to achieve it, under a range of conditions and control strategies, and we discuss advantageous strategies with respect to reducing the release resources and strategy costs (in terms of control mosquito numbers) required to achieve complete eradication of wild-type mosquitoes. PMID:23608633

Seirin Lee, S; Baker, R E; Gaffney, E A; White, S M

2013-08-21

55

Ross, Macdonald, and a Theory for the Dynamics and Control of Mosquito-Transmitted Pathogens  

Science.gov (United States)

Ronald Ross and George Macdonald are credited with developing a mathematical model of mosquito-borne pathogen transmission. A systematic historical review suggests that several mathematicians and scientists contributed to development of the Ross-Macdonald model over a period of 70 years. Ross developed two different mathematical models, Macdonald a third, and various “Ross-Macdonald” mathematical models exist. Ross-Macdonald models are best defined by a consensus set of assumptions. The mathematical model is just one part of a theory for the dynamics and control of mosquito-transmitted pathogens that also includes epidemiological and entomological concepts and metrics for measuring transmission. All the basic elements of the theory had fallen into place by the end of the Global Malaria Eradication Programme (GMEP, 1955–1969) with the concept of vectorial capacity, methods for measuring key components of transmission by mosquitoes, and a quantitative theory of vector control. The Ross-Macdonald theory has since played a central role in development of research on mosquito-borne pathogen transmission and the development of strategies for mosquito-borne disease prevention.

Smith, David L.; Battle, Katherine E.; Hay, Simon I.; Barker, Christopher M.; Scott, Thomas W.; McKenzie, F. Ellis

2012-01-01

56

Ross, macdonald, and a theory for the dynamics and control of mosquito-transmitted pathogens.  

Science.gov (United States)

Ronald Ross and George Macdonald are credited with developing a mathematical model of mosquito-borne pathogen transmission. A systematic historical review suggests that several mathematicians and scientists contributed to development of the Ross-Macdonald model over a period of 70 years. Ross developed two different mathematical models, Macdonald a third, and various "Ross-Macdonald" mathematical models exist. Ross-Macdonald models are best defined by a consensus set of assumptions. The mathematical model is just one part of a theory for the dynamics and control of mosquito-transmitted pathogens that also includes epidemiological and entomological concepts and metrics for measuring transmission. All the basic elements of the theory had fallen into place by the end of the Global Malaria Eradication Programme (GMEP, 1955-1969) with the concept of vectorial capacity, methods for measuring key components of transmission by mosquitoes, and a quantitative theory of vector control. The Ross-Macdonald theory has since played a central role in development of research on mosquito-borne pathogen transmission and the development of strategies for mosquito-borne disease prevention. PMID:22496640

Smith, David L; Battle, Katherine E; Hay, Simon I; Barker, Christopher M; Scott, Thomas W; McKenzie, F Ellis

2012-01-01

57

A synthetic sex ratio distortion system for the control of the human malaria mosquito  

Science.gov (United States)

It has been theorized that inducing extreme reproductive sex ratios could be a method to suppress or eliminate pest populations. Limited knowledge about the genetic makeup and mode of action of naturally occurring sex distorters and the prevalence of co-evolving suppressors has hampered their use for control. Here we generate a synthetic sex distortion system by exploiting the specificity of the homing endonuclease I-PpoI, which is able to selectively cleave ribosomal gene sequences of the malaria vector Anopheles gambiae that are located exclusively on the mosquito’s X chromosome. We combine structure-based protein engineering and molecular genetics to restrict the activity of the potentially toxic endonuclease to spermatogenesis. Shredding of the paternal X chromosome prevents it from being transmitted to the next generation, resulting in fully fertile mosquito strains that produce >95% male offspring. We demonstrate that distorter male mosquitoes can efficiently suppress caged wild-type mosquito populations, providing the foundation for a new class of genetic vector control strategies.

Galizi, Roberto; Doyle, Lindsey A.; Menichelli, Miriam; Bernardini, Federica; Deredec, Anne; Burt, Austin; Stoddard, Barry L.; Windbichler, Nikolai; Crisanti, Andrea

2014-01-01

58

Novel Acetylcholinesterase Target Site for Malaria Mosquito Control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Current anticholinesterase pesticides were developed during World War II and are toxic to mammals because they target a catalytic serine residue of acetylcholinesterases (AChEs) in insects and in mammals. A sequence analysis of AChEs from 73 species and a three-dimensional model of a malaria-carrying mosquito (Anopheles gambiae) AChE (AgAChE) reported here show that C286 and R339 of AgAChE are conserved at the opening of the active site of AChEs in 17 invertebrate and four insect species, res...

2006-01-01

59

Efficiency Evaluation of Nozawa-Style Black Light Trap for Control of Anopheline Mosquitoes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

House-residual spraying and insecticide-treated bed nets have achieved some success in controlling anthropophilic and endophagic vectors. However, these methods have relatively low efficacy in Korea because Anopheles sinensis, the primary malaria vector, is highly zoophilic and exophilic. So, we focused our vector control efforts within livestock enclosures using ultraviolet black light traps as a mechanical control measure. We found that black light traps captured significantly more mosquito...

2009-01-01

60

Multiple resistances and complex mechanisms of Anopheles sinensis mosquito: a major obstacle to mosquito-borne diseases control and elimination in China.  

Science.gov (United States)

Malaria, dengue fever, and filariasis are three of the most common mosquito-borne diseases worldwide. Malaria and lymphatic filariasis can occur as concomitant human infections while also sharing common mosquito vectors. The overall prevalence and health significance of malaria and filariasis have made them top priorities for global elimination and control programmes. Pyrethroid resistance in anopheline mosquito vectors represents a highly significant problem to malaria control worldwide. Several methods have been proposed to mitigate insecticide resistance, including rotational use of insecticides with different modes of action. Anopheles sinensis, an important malaria and filariasis vector in Southeast Asia, represents an interesting mosquito species for examining the consequences of long-term insecticide rotation use on resistance. We examined insecticide resistance in two An. Sinensis populations from central and southern China against pyrethroids, organochlorines, organophosphates, and carbamates, which are the major classes of insecticides recommended for indoor residual spray. We found that the mosquito populations were highly resistant to the four classes of insecticides. High frequency of kdr mutation was revealed in the central population, whereas no kdr mutation was detected in the southern population. The frequency of G119S mutation in the ace-1 gene was moderate in both populations. The classification and regression trees (CART) statistical analysis found that metabolic detoxification was the most important resistance mechanism, whereas target site insensitivity of L1014 kdr mutation played a less important role. Our results indicate that metabolic detoxification was the dominant mechanism of resistance compared to target site insensitivity, and suggests that long-term rotational use of various insecticides has led An. sinensis to evolve a high insecticide resistance. This study highlights the complex network of mechanisms conferring multiple resistances to chemical insecticides in mosquito vectors and it has important implication for designing and implementing vector resistance management strategies. PMID:24852174

Chang, Xuelian; Zhong, Daibin; Fang, Qiang; Hartsel, Joshua; Zhou, Guofa; Shi, Linna; Fang, Fujin; Zhu, Changliang; Yan, Guiyun

2014-05-01

 
 
 
 
61

Biorational insecticides for control of mosquitoes and black flies in Sinaloa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In Sinaloa Mexico the presence of mosquitoes is a important health problem, and each spring-summer season appear several species which include: Aedes aegypti (Linneus), Anopheles albimanus (Wiedemann), Culex quinquefasciatus (Say) and black flies of the Simulidae family. The control of larvae and adults of these insects are usually performed with chemical insecticides, so the use of biorational insecticides for control of these insects is novel, due to that have low environment impact. The ob...

2012-01-01

62

Wetland management strategies that enhance waterfowl habitats can also control mosquitoes.  

Science.gov (United States)

Two studies in California wetlands and a third in Minnesota wetlands indicate that management practices designed to enhance habitat quality for waterfowl can concurrently reduce mosquito problems. In a seasonally flooded pickleweed wetland in Suisun Marsh, Solano Co., CA, we demonstrated that reducing plant-cover by 50% increased benthic densities of chironomid midge and dytiscid beetle larvae; these insects can be important in waterfowl diets. This manipulation also concentrated Aedes melanimon and Culiseta inornata mosquito larvae along wetland perimeters; thus, the need for control measures was greatly restricted spatially. A study in 9 experimental ponds in Suisun Marsh demonstrated that higher water levels could enhance populations of the macroinvertebrates important in waterfowl diets; general macroinvertebrate densities were higher at 60 cm depths than 20 cm or 40 cm depths. In contrast, Cs. inornata densities were lowest at 60 cm depths and highest at 20 cm depths. A study conducted in a perennial-water cattail wetland in Minneapolis-St. Paul, MN, demonstrated that a temporary water-level drawdown, designed to enhance waterfowl habitat quality of perennial-water wetlands, also reduced densities of Coquillettidia perturbans mosquito larvae. These mosquitoes disappeared immediately after the drawdown, but even after water depths were restored to pre-drawdown levels, significant numbers did not reappear until 4 years post-drawdown. Studies in 202 other Minnesota wetlands also demonstrated the susceptibility of Cq. perturbans populations to drawdown, but the impact of drawdown was greater in stands of emergent cattail than in floating cattail. PMID:1431852

Batzer, D P; Resh, V H

1992-06-01

63

An assessment of mosquito production and nonchemical control measures in structural stormwater best management practices in southern California.  

Science.gov (United States)

A 3-year study was conducted to assess mosquito production in structural stormwater Best Management Practices (BMPs) installed by the California Department of Transportation in San Diego and Los Angeles Counties. Thirty-seven BMPs were monitored weekly for presence and relative abundance of immature mosquitoes and for conditions conducive to mosquito production. Species identified were Aedes squamiger, Anopheles franciscanus, An. hermsi, Culex quinquefasciatus, Cx. stigmatosoma, Cx. tarsalis, Culiseta incidens, and Cs. inornata. Structures designed with accessible, permanent sources of standing water in sumps, vaults, or basins were observed to support immatures all year. In BMPs intended to drain rapidly and completely, observed larval habitats resulted from design features, component failure, construction flaws, and non-stormwater runoff flows. Specific nonchemical mitigation measures to minimize or eliminate mosquito production were developed, implemented, and evaluated. This study provides a 1st assessment of mosquito production, species composition, and nonchemical control measures in structural stormwater BMPs in southern California. PMID:18437817

Metzger, Marco E; Myers, Charles M; Kluh, Susanne; Wekesa, J Wakoli; Hu, Renjie; Kramer, Vicki L

2008-03-01

64

Sustainable control of mosquito larvae in the field by the combined actions of the biological insecticide Bti and natural competitors.  

Science.gov (United States)

Integrated management of mosquitoes is becoming increasingly important, particularly in relation to avoiding recolonization of ponds after larvicide treatment. We conducted for the first time field experiments that involved exposing natural populations of the mosquito species Culex pipiens to: a) application of the biological insecticide Bacillus thuringiensis israelensis (Bti), b) the introduction of natural competitors (a crustacean community composed mainly of Daphnia spp.), or c) a combined treatment that involved both introduction of a crustacean community and the application of Bti. The treatment that involved only the introduction of crustaceans had no significant effect on mosquito larval populations, while treatment with Bti alone caused only a significant reduction in the abundance of mosquito larvae in the short-term (within 3-10 days after treatment). In contrast, the combined treatment rapidly reduced the abundance of mosquito larvae, which remained low throughout the entire observation period of 28 days. Growth of the introduced crustacean communities was favored by the immediate reduction in the abundance of mosquito larvae following Bti administration, thus preventing recolonization of ponds by mosquito larvae at the late period (days 14-28 after treatment). Both competition and the temporal order of establishment of different species are hence important mechanisms for efficient and sustainable mosquito control. PMID:23701611

Kroeger, Iris; Liess, Matthias; Dziock, Frank; Duquesne, Sabine

2013-06-01

65

Success of integrated methods of control of mosquitoes in India--a review.  

Science.gov (United States)

The integrated methodology for the control of vectors of diseases as well as mosquitoes has become an accepted concept amongst the public health experts. The feasibility of adopting this approach in different situations for mosquito control as per field trials by various institutions has been reviewed in this article. This concept, to some extent, has been in vogue under National Malaria Eradication Programme since long in a practicable way. Satisfactory results have been obtained wherever this approach has been applied carefully. The applicability of the integrated control methodology is not difficult provided various methods to be integrated are chosen and utilized in a rational way. Thorough health education is a prerequisite to awaken the community to accept the methods as part and parcel of routine life. PMID:2098414

Yadava, R L; Biswas, H; Rao, C K; Narasimham, M V; Thapar, B R

1990-06-01

66

Achieving high coverage of larval-stage mosquito surveillance: challenges for a community-based mosquito control programme in urban Dar es Salaam, Tanzania  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Preventing malaria by controlling mosquitoes in their larval stages requires regular sensitive monitoring of vector populations and intervention coverage. The study assessed the effectiveness of operational, community-based larval habitat surveillance systems within the Urban Malaria Control Programme (UMCP) in urban Dar es Salaam, Tanzania. Methods Cross-sectional surveys were carried out to assess the ability of community-owned resource per...

Chaki Prosper P; Govella Nicodem J; Shoo Bryson; Hemed Abdullah; Tanner Marcel; Fillinger Ulrike; Killeen Gerry F

2009-01-01

67

Comparative efficacy of the threespine stickleback (Gasterosteus aculeatus) and the mosquitofish (Gambusia affinis) for mosquito control.  

Science.gov (United States)

The effectiveness of the threespine stickleback as a mosquito control agent was compared to that of the mosquitofish in 28-m2 earthen ponds during 26-wk experiments where the 2 fish were stocked alone and together. Relative to ponds without fish, the stickleback was not effective for controlling larval mosquito populations; however, sticklebacks reduced the abundance of Culex pupae. Mosquitofish provided significant levels of control whether stocked alone or concurrently with the stickleback. As compared to mosquitofish alone, mosquito control was not significantly enhanced when both fish were stocked together. Mortality of adult sticklebacks was related to a gradient of increasing water temperature across the ponds rather than the direct effects of other abiotic factors such as low dissolved oxygen concentrations or biotic interactions with the mosquitofish. The stickleback exhibited a lower thermal tolerance and slower population recruitment as compared to the mosquitofish populations,which reproduced successfully in water > 33 degrees C and grew rapidly. Stickleback biomass either declined or increased slightly (approximately 50% of initial stocking weight). Mosquitofish biomass increased 33- to 38-fold at rates averaging between 0.079 and 0.095 g wet weight/g/day and total wet weight per pond at 6 wk after stocking did not differ significantly between the 2 mosquitofish treatments. PMID:10480131

Offill, Y A; Walton, W E

1999-09-01

68

Investigating preferences for mosquito-control technologies in Mozambique with latent class analysis  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background It is common practice to seek the opinions of future end-users during the development of innovations. Thus, the aim of this study is to investigate latent classes of users in Mozambique based on their preferences for mosquito-control technology attributes and covariates of these classes, as well as to explore which current technologies meet these preferences. Methods Surveys were administered in five rural villages in Mozambique. The data were analysed with latent class analysis. Results This study showed that users' preferences for malaria technologies varied, and people could be categorized into four latent classes based on shared preferences. The largest class, constituting almost half of the respondents, would not avoid a mosquito-control technology because of its cost, heat, odour, potential to make other health issues worse, ease of keeping clean, or inadequate mosquito control. The other three groups are characterized by the attributes which would make them avoid a technology; these groups are labelled as the bites class, by-products class, and multiple-concerns class. Statistically significant covariates included literacy, self-efficacy, willingness to try new technologies, and perceived seriousness of malaria for the household. Conclusions To become widely diffused, best practices suggest that end-users should be included in product development to ensure that preferred attributes or traits are considered. This study demonstrates that end-user preferences can be very different and that one malaria control technology will not satisfy everyone.

Barclay Victoria C

2011-07-01

69

The Effective Population Size of Malaria Mosquitoes: Large Impact of Vector Control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Malaria vectors in sub-Saharan Africa have proven themselves very difficult adversaries in the global struggle against malaria. Decades of anti-vector interventions have yielded mixed results—with successful reductions in transmission in some areas and limited impacts in others. These varying successes can be ascribed to a lack of universally effective vector control tools, as well as the development of insecticide resistance in mosquito populations. Understanding the impact of vector contr...

Athrey, Giridhar; Hodges, Theresa K.; Reddy, Michael R.; Overgaard, Hans J.; Matias, Abrahan; Ridl, Frances C.; Kleinschmidt, Immo; Caccone, Adalgisa; Slotman, Michel A.

2012-01-01

70

Genetically-modified mosquitoes for malaria control: requirements to be considered before field releases  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The technical feasibility of the development of transgenic mosquitoes highly refractory to (rodent) malaria parasites has been demonstrated in the laboratory. Following this proof of principle, genetic control of vectors could have an important role to play in the interruption of transmission of human malarias, if the main developmental and implementation challenges are adequately addressed. These include the establishment of a proof of efficacy and safety for humans and the environment in ca...

2006-01-01

71

Insecticide substitutes for DDT to control mosquitoes may be causes of several diseases.  

Science.gov (United States)

Malaria continues to be a public health problem in Bangladesh, despite efforts in the 1960s to eradicate the vectors through the use of DDT. At one point, eradication of malaria was acclaimed but later on it reappeared. The use of DDT is no more legally allowed in Bangladesh, which has been officially replaced by a number organophosphates and/or synthetic pyrethroids and their combinations in addition to the integrated vector management (IVM) package. IVM being a community approach is still to go a long way to be mass popular. Adulticides, larvicides, residual sprays, mosquito coil, insecticide-impregnated curtain, aerosol, etc. still serve as the major weapons of mosquito control. Thus, mosquito control still mostly depends on chemical insecticides. Although the use of DDT is banned in Bangladesh, there are reports on its illegal use in different forms. Moreover, there is tons of leftover DDT in Bangladesh, which is likely to cause several diseases. As per one report, about 500 MTs of DDT stockpiles are lying in the Medical Sub-Depots at Chittagong for over a period of 26 years. DDT is a persistent organic pollutant pesticide, which can cause diseases like cancer, endocrine disorder, disruption of immune system, embryonic abnormality, reproductive disorder, etc. Other chemical insecticides, which are replacing DDT, are also not free of hazardous impacts. IVM thus appears to be a wise approach requiring concerted efforts for the management of mosquito to control malaria. Such an IVM comprises use of Bacillus thuringiensis Berliner var. israelensis, methoprene, biocontrol agents, cleaning of breeding sites, pyrethroid-impregnated curtain, etc. Therefore, a wise effort should be adopted to completely stop the use of DDT, eliminate its stockpiles wherever they are in Bangladesh and to popularise the IVM, not the chemicals-based alternatives throughout the country. PMID:22956113

Rahman, Md Mahbubar

2013-04-01

72

Identification and characterization of a novel marine Bacillus cereus for mosquito control.  

Science.gov (United States)

Entomopathogenic bacteria to control mosquitoes are a promising environmentally friendly alternative to synthetic pesticides. In the present study, a novel mosquitocidal bacterium was isolated from marine soil collected from east coastal areas at Pondicherry (India). 16S rRNA gene sequence alignment depicted that this isolate belonged to Bacillus cereus VCRC-B520 (NCBI: KC-119192). Biochemical studies on bacterial growth, biomass, and toxin production have revealed that this strain could possibly be helpful in the production of a biopesticide in mosquito control. Toxicity assay with B. cereus against mosquito larvae has shown that the filariasis vector, Culex quinquefasciatus, is more susceptible than the other two species (Anopheles stephensi and Aedes aegypti). The LC50 and LC90 values for C. quinquefasciatus were 0.30 and 2.21 mg/L, respectively. No effect of B. cereus was found on nontargeted organisms. SDS-PAGE analysis and protein purification result from the cell mass of B. cereus have shown that a well-perceptible polypeptide was the dependable factor (85 kDa) for mosquitocidal action. Protein characterization (M/S MALDI-TOF) has shown that it is an endotoxin-specific insecticidal protein, namely "Cry4Aa". Phylogenetic analyses of 16S rDNA gene sequence from this marine isolate have revealed the presence of homology among closely related Bacillus strains. Therefore, considerable interest has been shown on the identification of a potential mosquitocidal bacterium from marine environment (B. cereus), which was not reported earlier in view of the current scenario of the rapid development of resistance to Bacillus sphaericus in mosquito vector control program. PMID:24192866

Poopathi, Subbiah; Mani, C; Thirugnanasambantham, K; Praba, V Lakshmi; Ahangar, Niyaz Ahmad; Balagangadharan, K

2014-01-01

73

Mosquito Specimens Making Technology  

Directory of Open Access Journals (Sweden)

Full Text Available Mosquito is a kind of important medical insects. Mosquito biological and morphological taxonomic research is the premise of effective control of mosquitoes. Specimen making of the mosquito egg, larvae, pupa and adult, genitalia is essential for taxonomic study. However, the technology for mosquito specimens making is yet to be improved and perfected. With many years of practice and improvement, this paper proposes the ideal and portable tools of specimen making, and the specimen making processing of the eggs, larvae, pupae, larval and pupal exuviae, adults, male and female genitalia, and also introduces the packaging and mailing method of mosquito pincushion specimens and slide specimens. These techniques have a lot of improvements on the basis of earlier protocols, and can provide with for the making, and transport of mosquito specimens.

WANG Chuang-xin

2013-05-01

74

Monitoring of larval habitats and mosquito densities in the Sudan savanna of Mali: implications for malaria vector control.  

Science.gov (United States)

In Mali, anopheline mosquito populations increase sharply during the rainy season, but are barely detectable in the dry season. This study attempted to identify the dry season mosquito breeding population in and near the village of Bancoumana, Mali, and in a fishing hamlet 5 km from this village and adjacent to the Niger River. In Bancoumana, most larval habitats were human made, and dried out in January-February. In contrast, in the fishing hamlet, productive larval habitats were numerous and found mainly during the dry season (January-May) as the natural result of drying riverbeds. Adult mosquitoes were abundant during the dry season in the fishermen hamlet and rare in Bancoumana. To the extent that the fishermen hamlet mosquito population seeds Bancoumana with the advent of the rainy season, vector control in this small hamlet may be a cost-effective way to ameliorate malaria transmission in the 40-times larger village. PMID:17620634

Sogoba, Nafomon; Doumbia, Seydou; Vounatsou, Penelope; Baber, Ibrahima; Keita, Moussa; Maiga, Mamoudou; Traoré, Sékou F; Touré, Abdoulaye; Dolo, Guimogo; Smith, Thomas; Ribeiro, José M C

2007-07-01

75

Field evaluation of a large-scale barrier application of bifenthrin on a golf course to control floodwater mosquitoes.  

Science.gov (United States)

In order to better understand the role a barrier application plays in an integrated mosquito management program, we applied a bifenthrin barrier application to a large golf course community and evaluated the mosquito population, service requests, and money spent for control from our barrier site as well as a site that was only treated via ground ultra-low-volume (ULV) application or that was left as a control site. Both the barrier application (t = 2.63, df = 126, P = 0.0147) and the ground ULV application (t = 2.49, df = 126, P = 0.0054) significantly reduced mosquito populations compared to the control, but means within treatments did not differ from each other. Mosquito populations in Centers for Disease Control and Prevention traps were reduced by 84% by barrier application and by 52% by ground ULV application at 6 wk posttreatment compared with untreated control. The 2 major species collected during the evaluation period were Anopheles crucians (81%) and Aedes atlanticus (13%). Anopheles crucians was significantly reduced compared with controls for the barrier application (t = 1.55, df = 126, P = 0.003) and ground ULV application (t = 1.85, df = 126, P = 0.052). Aedes atlanticus was significantly reduced by the barrier application (t = 1.54, df = 128, P = 0.002) but not by ground ULV application (P = 0.083). Overall the barrier application resulted in a significant decrease (chi2 = 35.4, df = 1, P floodwater mosquito populations. PMID:23833902

Qualls, Whitney A; Smith, Michael L; Muller, Gunter C; Zhao, Tong-Yan; Xue, Rui-De

2012-09-01

76

Monitoring the aquatic toxicity of mosquito vector control spray pesticides to freshwater receiving waters.  

Science.gov (United States)

Pesticides are applied to state and local waterways in California to control insects such as mosquitoes, which are known to serve as a vector for West Nile Virus infection of humans. The California State Water Resources Control Board adopted a National Pollutant Discharge Elimination System General Permit to address the discharge to waters of the United States of pesticides resulting from adult and larval mosquito control. Because pesticides used in spray activities have the potential to cause toxicity to nontarget organisms in receiving waters, the current study was designed to determine whether toxicity testing provides additional, useful environmental risk information beyond chemical analysis in monitoring spray pesticide applications. Monitoring included a combination of aquatic toxicity tests and chemical analyses of receiving waters from agricultural, urban, and wetland habitats. The active ingredients monitored included the organophosphate pesticides malathion and naled, the pyrethroid pesticides etofenprox, permethrin, and sumithrin, pyrethrins, and piperonyl butoxide (PBO). Approximately 15% of the postapplication water samples were significantly toxic. Toxicity of half of these samples was attributed to the naled breakdown product dichlorvos. Toxicity of 2 other water samples likely occurred when PBO synergized the effects of pyrethroid pesticides that were likely present in the receiving system. Four of 43 postapplication sediment samples were significantly more toxic than their corresponding pre-application samples, but none of the observed toxicity was attributed to the application events. These results indicate that many of the spray pesticides used for adult mosquito control do not pose significant acute toxicity risk to invertebrates in receiving systems. In the case of naled in water, analysis of only the active ingredient underestimated potential impacts to the receiving system, because toxicity was attributed to the breakdown product, dichlorvos. Toxicity testing can provide useful risk information about unidentified, unmeasured toxicants or mixtures of toxicants. In this case, toxicity testing provided information that could lead to the inclusion of dichlorvos monitoring as a permit requirement. Integr Environ Assess Manag 2014;10:449-455. © 2014 SETAC. PMID:24659580

Phillips, Bryn M; Anderson, Brian S; Voorhees, Jennifer P; Siegler, Katie; Denton, Debra; TenBrook, Patti; Larsen, Karen; Isorena, Philip; Tjeerdema, Ron S

2014-07-01

77

A tool box for operational mosquito larval control: preliminary results and early lessons from the Urban Malaria Control Programme in Dar es Salaam, Tanzania  

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Abstract Background As the population of Africa rapidly urbanizes, large populations could be protected from malaria by controlling aquatic stages of mosquitoes if cost-effective and scalable implementation systems can be designed. Methods A recently initiated Urban Malaria Control Programme in Dar es Salaam delegates responsibility for routine mosquito control and surveillance to modestly-paid community members, known as Community-Owned Resource Persons (CORPs)...

Fillinger Ulrike; Kannady Khadija; William George; Vanek Michael J; Dongus Stefan; Nyika Dickson; Geissbühler Yvonne; Chaki Prosper P; Govella Nico J; Mathenge Evan M; Singer Burton H; Mshinda Hassan; Lindsay Steven W; Tanner Marcel; Mtasiwa Deo

2008-01-01

78

Geostatistical evaluation of integrated marsh management impact on mosquito vectors using before-after-control-impact (BACI design  

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Full Text Available Abstract Background In many parts of the world, salt marshes play a key ecological role as the interface between the marine and the terrestrial environments. Salt marshes are also exceedingly important for public health as larval habitat for mosquitoes that are vectors of disease and significant biting pests. Although grid ditching and pesticides have been effective in salt marsh mosquito control, marsh degradation and other environmental considerations compel a different approach. Targeted habitat modification and biological control methods known as Open Marsh Water Management (OMWM had been proposed as a viable alternative to marsh-wide physical alterations and chemical control. However, traditional larval sampling techniques may not adequately assess the impacts of marsh management on mosquito larvae. To assess the effectiveness of integrated OMWM and marsh restoration techniques for mosquito control, we analyzed the results of a 5-year OMWM/marsh restoration project to determine changes in mosquito larval production using GIS and geostatistical methods. Methods The following parameters were evaluated using "Before-After-Control-Impact" (BACI design: frequency and geographic extent of larval production, intensity of larval production, changes in larval habitat, and number of larvicide applications. The analyses were performed using Moran's I, Getis-Ord, and Spatial Scan statistics on aggregated before and after data as well as data collected over time. This allowed comparison of control and treatment areas to identify changes attributable to the OMWM/marsh restoration modifications. Results The frequency of finding mosquito larvae in the treatment areas was reduced by 70% resulting in a loss of spatial larval clusters compared to those found in the control areas. This effect was observed directly following OMWM treatment and remained significant throughout the study period. The greatly reduced frequency of finding larvae in the treatment areas led to a significant decrease (~44% in the number of times when the larviciding threshold was reached. This reduction, in turn, resulted in a significant decrease (~74% in the number of larvicide applications in the treatment areas post-project. The remaining larval habitat in the treatment areas had a different geographic distribution and was largely confined to the restored marsh surface (i.e. filled-in mosquito ditches; however only ~21% of the restored marsh surface supported mosquito production. Conclusion The geostatistical analysis showed that OMWM demonstrated considerable potential for effective mosquito control and compatibility with other natural resource management goals such as restoration, wildlife habitat enhancement, and invasive species abatement. GPS and GIS tools are invaluable for large scale project design, data collection, and data analysis, with geostatistical methods serving as an alternative or a supplement to the conventional inference statistics in evaluating the project outcome.

Dempsey Mary E

2009-06-01

79

Transcriptional control is relevant in the modulation of mosquito ferritin synthesis by iron.  

Science.gov (United States)

In yellow fever mosquito cells (Aag2 clone), iron treatment induces a threefold increase in ferritin message (fer mRNA) and protein (ferritin) by 16 h. These data contrast with work in mammalian hepatocytes and fibroblasts in which fer mRNA levels do not change with iron stimulation, but ferritin levels increase 50-fold. Pretreatment of the Aag2 cells with actinomycin D blocks induction of fer mRNA and reduces the ferritin subunit synthesis, suggesting that iron induction of ferritin subunit synthesis is subjected to transcriptional control. A putative iron-regulatory protein has also been identified in cytoplasmic extracts from Aag2 cells. PMID:10542070

Pham, D Q; Winzerling, J J; Dodson, M S; Law, J H

1999-11-01

80

Temporal and spatial distribution of anopheline mosquitos in an Ethiopian village: implications for malaria control strategies.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The spatial and temporal distribution of Anopheles gambiae mosquitos in houses in the village of Sille in Ethiopia was monitored in 1990-91. Monthly mosquito densities in over 300 houses were obtained, and the data for each month were plotted on maps, which indicated clustering of mosquitos within the village. Spatial analysis using "kriging" techniques demonstrated clustering towards the edges of the village, the pattern of which changed with time. For example, the low density of mosquitos i...

Ribeiro, J. M.; Seulu, F.; Abose, T.; Kidane, G.; Teklehaimanot, A.

1996-01-01

 
 
 
 
81

A novel cost-effective medium for the production of Bacillus thuringiensis subsp. israelensis for mosquito control.  

Science.gov (United States)

Bacillus thuringiensis subsp. israelensis (Bti) has been used for mosquito-control programmes the world-wide. Indeed, the large-scale production of Bti for mosquito control is very expensive due to the high cost of its culture. In the present study, we attempted to widen the scope in developing cost-effective culture medium for Bti production, based on the raw materials available on the biosphere, including coconut cake powder, CCP (Cocos nucifera), neem cake powder, NCP (Azadirachta indica) and groundnut cake powder, GCP (Arachis hypogea). Among these raw materials, the biomass production of Bti, sporulation and toxin synthesizing from 'CCP' in combination with mineral salt (MnCl(2)) was comfortably satisfactory. Bioassays with mosquito species (Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti) and field trials were also satisfactory. The present investigation suggests that coconut cake-based culture medium can be used as an alternative for industrial production of Bti in mosquito-control programme. Therefore, the study is very important from the point of effective production of Bti from cost-effective culture medium for the control of mosquito vectors. PMID:22543607

Poopathi, Subbiah; Archana, B

2012-03-01

82

Controle de mosquitos com base em larvicidas no Estado do Rio Grande do Sul, Brasil: a escolha do agente de controle / Mosquito control based on larvicides in the State of Rio Grande do Sul, Brazil: choice of the control agent  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Desenvolveu-se neste estudo uma comparação entre larvicidas químicos e biológicos usados em programas de controle de mosquitos no Rio Grande do Sul. Em bioensaios de laboratório contra Culex quinquefasciatus constatou-se que as formulações biológicas líquidas Vectobac 12 AS e Teknar 3000 (Bacillus t [...] huringiensis israelensis), ABG 6262 líquido e em pó (B. sphaericus 2362), foram altamente eficazes. Também as formulações experimentais de B. thuringiensis israelensis produzidas em laboratórios brasileiros foram consideradas adequadas. Entre as formulações químicas, os compostos piretróides Pirisa e K-Othrine produziram resultados melhores do que os organo-fosforados Lebaycid e Abate. Estes últimos produziram respostas dez vezes mais fracas do que o previsto em outros estudos. Em condições de campo, a dose de 1250 mg/m² para as formulações biológicas foi considerada adequada para a rotina das aplicações, porque permite superar as influências físicas do meio sobre os resultados. Somente as formulações de B. sphaericus produziram interrupções nas reinfestações dos focos de culicídeos observados. Períodos de até 39 semanas sem reinfestações foram observados em focos naturais e de um mês sem sobrevivência foi observado em tanques, onde procedia-se a reinfestação artificial. Este estudo sugere que as alternativas biológicas devem ser consideradas em programas de controle de mosquitos. Elas podem superar os problemas de resistência e eliminação, bem como da ausência de efeito residual nas aplicações de larvicidas. Abstract in english A comparison between chemical and biological larvicides in routine operations against mosquitoes in Rio Grande do Sul State was carried out in this study. In laboratory bioassays against Culex quinquefasciatus, biological formulations Vectobac 12 AS and Teknar 3000 (Bacillus thuringiensis israelensi [...] s) as well as ABG 6262 (B. sphaericus 2362), both in liquid and powder form, were highly effective. Locally produced B.thuringiensis israelensis, formulations also yielded good results. Among chemical larvicides, pyrethroid compounds Pirisa and K-Othrine yielded better results than the organophosphates Lebaycid and Abate. These last formulations yielded responses ten weaker than predicted in other studies. Under field conditions, a dose of 1250 mg/m² for biological formulations was considered adequate for routine application because at this level it is possible to overcome physical influences on results. Only B.sphaericus preparations caused important disruption of mosquito colonization in active breeding sites. Up to 39 weeks were tabulated without complete colonization in natural conditions and one month in artificially colonized tanks. This study suggests that biological alternatives should be considered in mosquito control programs. They may be a solution to such problems as resistance to larvicides, elimination of natural enemies, and short-lasting effects of applications.

Antônio L., Ruas-Neto; Sydnei M., Silveira; Evandro Ricardo da C., Colares.

83

Controle de mosquitos com base em larvicidas no Estado do Rio Grande do Sul, Brasil: a escolha do agente de controle Mosquito control based on larvicides in the State of Rio Grande do Sul, Brazil: choice of the control agent  

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Full Text Available Desenvolveu-se neste estudo uma comparação entre larvicidas químicos e biológicos usados em programas de controle de mosquitos no Rio Grande do Sul. Em bioensaios de laboratório contra Culex quinquefasciatus constatou-se que as formulações biológicas líquidas Vectobac 12 AS e Teknar 3000 (Bacillus thuringiensis israelensis, ABG 6262 líquido e em pó (B. sphaericus 2362, foram altamente eficazes. Também as formulações experimentais de B. thuringiensis israelensis produzidas em laboratórios brasileiros foram consideradas adequadas. Entre as formulações químicas, os compostos piretróides Pirisa e K-Othrine produziram resultados melhores do que os organo-fosforados Lebaycid e Abate. Estes últimos produziram respostas dez vezes mais fracas do que o previsto em outros estudos. Em condições de campo, a dose de 1250 mg/m² para as formulações biológicas foi considerada adequada para a rotina das aplicações, porque permite superar as influências físicas do meio sobre os resultados. Somente as formulações de B. sphaericus produziram interrupções nas reinfestações dos focos de culicídeos observados. Períodos de até 39 semanas sem reinfestações foram observados em focos naturais e de um mês sem sobrevivência foi observado em tanques, onde procedia-se a reinfestação artificial. Este estudo sugere que as alternativas biológicas devem ser consideradas em programas de controle de mosquitos. Elas podem superar os problemas de resistência e eliminação, bem como da ausência de efeito residual nas aplicações de larvicidas.A comparison between chemical and biological larvicides in routine operations against mosquitoes in Rio Grande do Sul State was carried out in this study. In laboratory bioassays against Culex quinquefasciatus, biological formulations Vectobac 12 AS and Teknar 3000 (Bacillus thuringiensis israelensis as well as ABG 6262 (B. sphaericus 2362, both in liquid and powder form, were highly effective. Locally produced B.thuringiensis israelensis, formulations also yielded good results. Among chemical larvicides, pyrethroid compounds Pirisa and K-Othrine yielded better results than the organophosphates Lebaycid and Abate. These last formulations yielded responses ten weaker than predicted in other studies. Under field conditions, a dose of 1250 mg/m² for biological formulations was considered adequate for routine application because at this level it is possible to overcome physical influences on results. Only B.sphaericus preparations caused important disruption of mosquito colonization in active breeding sites. Up to 39 weeks were tabulated without complete colonization in natural conditions and one month in artificially colonized tanks. This study suggests that biological alternatives should be considered in mosquito control programs. They may be a solution to such problems as resistance to larvicides, elimination of natural enemies, and short-lasting effects of applications.

Antônio L. Ruas-Neto

1994-06-01

84

Controle de mosquitos com base em larvicidas no Estado do Rio Grande do Sul, Brasil: a escolha do agente de controle / Mosquito control based on larvicides in the State of Rio Grande do Sul, Brazil: choice of the control agent  

Scientific Electronic Library Online (English)

Full Text Available SciELO Public Health | Language: Portuguese Abstract in portuguese Desenvolveu-se neste estudo uma comparação entre larvicidas químicos e biológicos usados em programas de controle de mosquitos no Rio Grande do Sul. Em bioensaios de laboratório contra Culex quinquefasciatus constatou-se que as formulações biológicas líquidas Vectobac 12 AS e Teknar 3000 (Bacillus t [...] huringiensis israelensis), ABG 6262 líquido e em pó (B. sphaericus 2362), foram altamente eficazes. Também as formulações experimentais de B. thuringiensis israelensis produzidas em laboratórios brasileiros foram consideradas adequadas. Entre as formulações químicas, os compostos piretróides Pirisa e K-Othrine produziram resultados melhores do que os organo-fosforados Lebaycid e Abate. Estes últimos produziram respostas dez vezes mais fracas do que o previsto em outros estudos. Em condições de campo, a dose de 1250 mg/m² para as formulações biológicas foi considerada adequada para a rotina das aplicações, porque permite superar as influências físicas do meio sobre os resultados. Somente as formulações de B. sphaericus produziram interrupções nas reinfestações dos focos de culicídeos observados. Períodos de até 39 semanas sem reinfestações foram observados em focos naturais e de um mês sem sobrevivência foi observado em tanques, onde procedia-se a reinfestação artificial. Este estudo sugere que as alternativas biológicas devem ser consideradas em programas de controle de mosquitos. Elas podem superar os problemas de resistência e eliminação, bem como da ausência de efeito residual nas aplicações de larvicidas. Abstract in english A comparison between chemical and biological larvicides in routine operations against mosquitoes in Rio Grande do Sul State was carried out in this study. In laboratory bioassays against Culex quinquefasciatus, biological formulations Vectobac 12 AS and Teknar 3000 (Bacillus thuringiensis israelensi [...] s) as well as ABG 6262 (B. sphaericus 2362), both in liquid and powder form, were highly effective. Locally produced B.thuringiensis israelensis, formulations also yielded good results. Among chemical larvicides, pyrethroid compounds Pirisa and K-Othrine yielded better results than the organophosphates Lebaycid and Abate. These last formulations yielded responses ten weaker than predicted in other studies. Under field conditions, a dose of 1250 mg/m² for biological formulations was considered adequate for routine application because at this level it is possible to overcome physical influences on results. Only B.sphaericus preparations caused important disruption of mosquito colonization in active breeding sites. Up to 39 weeks were tabulated without complete colonization in natural conditions and one month in artificially colonized tanks. This study suggests that biological alternatives should be considered in mosquito control programs. They may be a solution to such problems as resistance to larvicides, elimination of natural enemies, and short-lasting effects of applications.

Antônio L., Ruas-Neto; Sydnei M., Silveira; Evandro Ricardo da C., Colares.

85

Door to Door Survey and Community Participation to Implement a New County Mosquito Control Program in Wayne County, North Carolina, USA  

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Full Text Available Community involvement in mosquito management programs provides more sustainable and effective organization and service. A door to door survey in Wayne County, NC carried out by student volunteers, resulted in 60 household responses. Residents had not previously experienced outreach from the county (88%, and 95% of them thought the student door to door survey was an effective form of outreach. One third of the residents thought mosquitoes were severe where they lived, but only 9% thought they had any containers in their yard that might breed mosquitoes. Only 15% of the residents were concerned about mosquito borne diseases. These responses provide evidence that outreach and education on mosquito control and diseases were necessary steps for future mosquito control community planning.

Timothy Kelley

2009-07-01

86

Aerial and Tidal Transport of Mosquito Control Pesticides into the Florida Keys National Marine Sanctuary  

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Full Text Available This project was undertaken as the initial monitoring program to determine if mosquito adulticides applied along the Florida Keys cause adverse ecological effects in the Florida Keys National Marine Sanctuary (FKNMS.The study monitored the distribution and persistence of two mosquito adulticides,permethrin and dibrom (naled,during three separate routine applications by the Florida Keys Mosquito Control District.The approach was to determine if toxic concentrations of the pesticides entered the FKNMS by aerial drift or tidal transport.The amount of pesticide entering the FKNMS by way of aerial drift was monitored by collection on glass fiber filter pads,set on floats in a grid pattern on either side of the FKNMS.Permethrin was recovered from filter pads on the leeward side for each of the three applications,ranging from 0.5 to 50.1 µg/m² throughout the study.Tidal current transport was monitored by collection of surface and subsurface water samples at each grid site.Tidal transport of naled and dichlorvos (naled degradation productwas apparent in the adjacent waters of the FKNMS.These compounds were detected in subsurface,offshore water at 0.1 to 0.6 µg/l,14 hr after application.Permethrin was not detected in offshore water samples; however, concentrations ranging from 5.1 to 9.4 µg/l were found in surface water from the canal system adjacent to the application route.Comparison of the observed environmental concentrations with toxicity data (permethrin LC-50,96 hr for Mysidopsis bahia =0.02 µg/lindicated a potential hazard to marine invertebrates in the canals with possible tidal transport to other areas.Para determinar si los adulticidas de mosquitos,aplicados en los Cayos de la Florida,causan efectos ecológicos adversos en el Santuario Marino Nacional de los Cayos de la Florida,se monitoreó la distribución y persistencia de dos adulticidas de mosquitos.Estos fueron permetrina y dibrom (naled.Se trabajó durante tres aplicaciones rutinarias hechas por la Unidad de Control de Mosquitos de los Cayos de la Florida.La finalidad era determinar si concentraciones tóxicas de los plaguicidas llegaban al santuario por transporte aéreo o por las corrientes de marea.La cantidad de plaguicida que entra por vía aérea fue monitoreada utilizando filtros de fibra de vidrio,montados en flotadores dispuestos sistemáticamente a ambos lados del FKNMS. La Permetrina fue recuperada en filtros a sotavento del santuario durante tres aplicaciones,con un ámbito entre 0.5 y 50.1 µg/m² durante todo el estudio.El transporte por corrientes de marea fue monitoreado recolectando muestras de agua superficiales y subsuperficiales en puntos definidos.Se notó el transporte por mareas de naled y diclorvos (producto degradado de naleden aguas adyacentes al santuario.Estos compuestos fueron detectados en muestras subsuperficiales en aguas fuera de la costa con concentraciones de 0.1 a 0.6 µg/l,14 hr después de la aplicación.La Permetrina no fue detectada en muestras de agua fuera de la costa;sin embargo,hubo concentraciones de 5.1 a 9.4 µg/l en aguas superficiales del sistema de canales adyacente a la ruta de aplicación. Comparaciones de las concentraciones observadas con información toxicológica (permetrina LC-50,96 hr para Mysidopsis bahia =0.02 µg/lindican un peligro potencial para invertebrados marinos en los canales y la posibilidad de transporte por mareas a otras áreas.

R.H Pierce

2005-05-01

87

Aerial and Tidal Transport of Mosquito Control Pesticides into the Florida Keys National Marine Sanctuary  

Scientific Electronic Library Online (English)

Full Text Available SciELO Costa Rica | Language: English Abstract in spanish Para determinar si los adulticidas de mosquitos,aplicados en los Cayos de la Florida,causan efectos ecológicos adversos en el Santuario Marino Nacional de los Cayos de la Florida,se monitoreó la distribución y persistencia de dos adulticidas de mosquitos.Estos fueron permetrina y dibrom (naled).Se t [...] rabajó durante tres aplicaciones rutinarias hechas por la Unidad de Control de Mosquitos de los Cayos de la Florida.La finalidad era determinar si concentraciones tóxicas de los plaguicidas llegaban al santuario por transporte aéreo o por las corrientes de marea.La cantidad de plaguicida que entra por vía aérea fue monitoreada utilizando filtros de fibra de vidrio,montados en flotadores dispuestos sistemáticamente a ambos lados del FKNMS. La Permetrina fue recuperada en filtros a sotavento del santuario durante tres aplicaciones,con un ámbito entre 0.5 y 50.1 µg/m² durante todo el estudio.El transporte por corrientes de marea fue monitoreado recolectando muestras de agua superficiales y subsuperficiales en puntos definidos.Se notó el transporte por mareas de naled y diclorvos (producto degradado de naled)en aguas adyacentes al santuario.Estos compuestos fueron detectados en muestras subsuperficiales en aguas fuera de la costa con concentraciones de 0.1 a 0.6 µg/l,14 hr después de la aplicación.La Permetrina no fue detectada en muestras de agua fuera de la costa;sin embargo,hubo concentraciones de 5.1 a 9.4 µg/l en aguas superficiales del sistema de canales adyacente a la ruta de aplicación. Comparaciones de las concentraciones observadas con información toxicológica (permetrina LC-50,96 hr para Mysidopsis bahia =0.02 µg/l)indican un peligro potencial para invertebrados marinos en los canales y la posibilidad de transporte por mareas a otras áreas. Abstract in english This project was undertaken as the initial monitoring program to determine if mosquito adulticides applied along the Florida Keys cause adverse ecological effects in the Florida Keys National Marine Sanctuary (FKNMS).The study monitored the distribution and persistence of two mosquito adulticides,pe [...] rmethrin and dibrom (naled),during three separate routine applications by the Florida Keys Mosquito Control District.The approach was to determine if toxic concentrations of the pesticides entered the FKNMS by aerial drift or tidal transport.The amount of pesticide entering the FKNMS by way of aerial drift was monitored by collection on glass fiber filter pads,set on floats in a grid pattern on either side of the FKNMS.Permethrin was recovered from filter pads on the leeward side for each of the three applications,ranging from 0.5 to 50.1 µg/m² throughout the study.Tidal current transport was monitored by collection of surface and subsurface water samples at each grid site.Tidal transport of naled and dichlorvos (naled degradation product)was apparent in the adjacent waters of the FKNMS.These compounds were detected in subsurface,offshore water at 0.1 to 0.6 µg/l,14 hr after application.Permethrin was not detected in offshore water samples; however, concentrations ranging from 5.1 to 9.4 µg/l were found in surface water from the canal system adjacent to the application route.Comparison of the observed environmental concentrations with toxicity data (permethrin LC-50,96 hr for Mysidopsis bahia =0.02 µg/l)indicated a potential hazard to marine invertebrates in the canals with possible tidal transport to other areas.

Pierce, R.H; Henry, M.S; Blum, T.C; Mueller, E.M.

88

Aerial and tidal transport of mosquito control pesticides into the Florida Keys National Marine Sanctuary  

International Nuclear Information System (INIS)

This project was undertaken as the initial monitoring program to determine if mosquito adulticides applied along the Florida Keys cause adverse ecological effects in the Florida Keys National Marine Sanctuary (FKNMS). The study monitored the distribution and persistente of two mosquito adulticides, permethrin and dibrom (naled), during three separate routine applications by the Florida Keys Mosquito Control District. The approach was to determine if toxic concentrations of the pesticides entered the FKNMS by aerial drift or tidal transport. The amount of pesticide entering the FKNMS by way of aerial drift was monitored by collection on glass fiber filter pads, set on floats in a grid pattern on either side of the FKNMS. Permethrin was recovered from filter pads on the leeward side for each of the three applications, ranging from 0.5 to 50.1 ?g/m2 throughout the study. Tidal current transport was monitored by collection of surface and subsurface water samples at each grid site. Tidal transport of naled and dichlorvos (naled degradation product) was apparent in the adjacent waters of the FKNMS. These compounds were detected in subsurface, offshore water at 0.1 to 0.6 gg/l, 14 hr after application. Permethrin was not detected in offshore water samples; however, concentrations ranging from 5.1 to 9.4 ?g/1 were found in surface water from the canal system adjacent to the application route. Comparison of the observed environmental concentrations with toxicity data (permethrin LC-50, 96 hr for Mysidopsis bahia = 0.02 ?g/1) indicated a potential hazard to marine invertebrates in the canals with possible tidal transport to other areas

2005-05-01

89

Achieving high coverage of larval-stage mosquito surveillance: challenges for a community-based mosquito control programme in urban Dar es Salaam, Tanzania  

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Full Text Available Abstract Background Preventing malaria by controlling mosquitoes in their larval stages requires regular sensitive monitoring of vector populations and intervention coverage. The study assessed the effectiveness of operational, community-based larval habitat surveillance systems within the Urban Malaria Control Programme (UMCP in urban Dar es Salaam, Tanzania. Methods Cross-sectional surveys were carried out to assess the ability of community-owned resource persons (CORPs to detect mosquito breeding sites and larvae in areas with and without larviciding. Potential environmental and programmatic determinants of habitat detection coverage and detection sensitivity of mosquito larvae were recorded during guided walks with 64 different CORPs to assess the accuracy of data each had collected the previous day. Results CORPs reported the presence of 66.2% of all aquatic habitats (1,963/2,965, but only detected Anopheles larvae in 12.6% (29/230 of habitats that contained them. Detection sensitivity was particularly low for late-stage Anopheles (2.7%, 3/111, the most direct programmatic indicator of malaria vector productivity. Whether a CORP found a wet habitat or not was associated with his/her unfamiliarity with the area (Odds Ratio (OR [95% confidence interval (CI] = 0.16 [0.130, 0.203], P Conclusions Accessibility of habitats in urban settings presents a major challenge because the majority of compounds are fenced for security reasons. Furthermore, CORPs under-reported larvae especially where larvicides were applied. This UMCP system for larval surveillance in cities must be urgently revised to improve access to enclosed compounds and the sensitivity with which habitats are searched for larvae.

Shoo Bryson

2009-12-01

90

[Mosquito control based on larvicides in the State of Rio Grande do Sul, Brazil: choice of the control agent].  

Science.gov (United States)

A comparison between chemical and biological larvicides in routine operations against mosquitoes in Rio Grande do Sul State was carried out in this study. In laboratory bioassays against Culex quinquefasciatus, biological formulations Vectobac 12 AS and Teknar 3000 (Bacillus thuringiensis israelensis) as well as ABG 6262 (B. sphaericus 2362), both in liquid and powder form, were highly effective. Locally produced B. thuringiensis israelensis, formulations also yielded good results. Among chemical larvicides, pyrethroid compounds Pirisa and K-Othrine yielded better results than the organophosphates Lebaycid and Abate. These last formulations yielded responses ten weaker than predicted in other studies. Under field conditions, a dose of 1250 mg/m2 for biological formulations was considered adequate for routine application because at this level it is possible to overcome physical influences on results. Only B. sphaericus preparations caused important disruption of mosquito colonization in active breeding sites. Up to 39 weeks were tabulated without complete colonization in natural conditions and one month in artificially colonized tanks. This study suggests that biological alternatives should be considered in mosquito control programs. They may be a solution to such problems as resistance to larvicides, elimination of natural enemies, and short-lasting effects of applications. PMID:14762563

Ruas-Neto, A L; Silveira, S M; Colares, E R

1994-01-01

91

Biorational insecticides for control of mosquitoes and black flies in Sinaloa  

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Full Text Available In Sinaloa Mexico the presence of mosquitoes is a important health problem, and each spring-summer season appear several species which include: Aedes aegypti (Linneus, Anopheles albimanus (Wiedemann, Culex quinquefasciatus (Say and black flies of the Simulidae family. The control of larvae and adults of these insects are usually performed with chemical insecticides, so the use of biorational insecticides for control of these insects is novel, due to that have low environment impact. The objective of this work is to give known to the different biorational insecticides and their biological effects (inhibitor, insect repellent, larvicide, adulticide, that can be used to combat to different development stages of these insects. As well as show the progress of a study on the effectiveness of neem extracts, garlic, cinnamon, albahaca and cypermethrin at low doses (0.25,0.5 and 1ml/L, for control of larvae and adults of black flies in the unicipality of El Fuerte, Sinaloa. By the mode of action, the biorational that can doing use for the control of theseinsects were: Spinosad, and Bacillus thuringiensis (Berliner var. israeliensis for larvae control, Spinosad and Beauveria bassiana (Vuill. for adults; as well as extracts of neem, garlic, cinnamon and albahaca for both stages. The preliminary results of the study showed that the effectiveness application in tourist sites, through aerial spraying of cypermethrin at low doses and the plants extracts, allow low the index of larvae and infestation of mosquitoes and blackflies, decreasing the discomfort caused by these insects in the place of study.

Cipriano García Gutiérrez

2012-09-01

92

Impact of mating behaviour on the success of malaria control through a single inundative release of transgenic mosquitoes.  

Science.gov (United States)

Transgenic mosquitoes are a potential tool for the control or eradication of insect-vectored diseases. For malaria, one possible strategy relies on the introduction of malaria-refractory transgenes into wild Anopheles mosquito populations that would limit their capacity to transmit the disease. The success of such an approach obviously depends on a variety of factors. By developing a model that integrates both population genetics and epidemiology, we explore how mosquito mating preferences and the cost and efficacy of refractoriness affects the long-term prevalence of malaria in humans subsequent to a single generation inundative release of male transgenic mosquitoes. As may be intuitively expected, mating discrimination by wild-type individuals against transgenic ones generally reduces the probability that transgenes become stably established at a high frequency in mosquito populations. We also show that in circumstances where transgenic individuals exhibit some degree of discrimination against wild-type individuals, this can favour the spread of refractory alleles and lead to a significant reduction in malaria prevalence in the human population (if the efficacy of a dominant refractory mechanism exceeds at least 75%). The existence of such a non-intuitive outcome highlights the practical value of increasing the understanding of Anopheles mating preferences in the wild as a means to harness them in the implementation of population replacement approaches. Potential strategies by which previously described mating preferences of Anopheles gambiae populations could be exploited to manipulate the mate choice of transgenic release stocks are discussed. PMID:24440174

Boëte, C; Agusto, F B; Reeves, R G

2014-04-21

93

Genetics as a component of vector mosquito control in East Africa  

International Nuclear Information System (INIS)

Among the proposed genetic control methods that have been tested with a degree of success are the release of sterile males, cytoplasmically incompatible strains and strains carrying chromosomal aberrations. In East Africa, the most important mosquitoes are Anopheles gambiae sensu strictu, which transmits malaria, filariasis and the O'nyong-nyong virus; An. arabiensis, which transmits malaria, filariasis and the Tatguine virus; and An. funestus, which transmits malaria, filariasis and the O'nyong-nyong and Tanga viruses. Other important vectors are Aedes simpsoni, which transmits yellow fever, and Ae. africanus, which is responsible for the forest cycle of the disease among monkeys. Cytological examination of specimens of An. gambiae sensu lato resulted in 804 positive identifications of the XB type chromosome only, indicating that An. arabiensis is the most abundant, and probably the only, member of the complex present, and constitutes close to 65.7% of the total mosquito population. Blood meal analysis of 1024 specimens showed its marked preference for bovid (51.9%) and human (28.1%) blood. Sporozoite rating by dissection and enzyme linked immunosorbent assay averaged 0.02%. Control methods tried in the past include chemical spraying and environmental management in the Kisumu area. A trial against An. arabiensis is suggested at Karima village, in Mwea, whereby an integrated approach incorporating environmental, chemical and genetic measures could be undertaken. This would take advantage of the low population during the dry season from mid-December to mid-April and would involve biological larviciding, mass pyrethrum spraying and the release of sterile males. There is a lack of adequate genetic knowledge of this species, especially genetic markers and linkage relationships, even though chromosome maps are available and inversion polymorphism is better understood. Notice should be taken of the reportedly discouraging results of genetic control trials, where failure has been attributed to immigration, poor competitiveness of laboratory produced males, failure to mate or density dependent mortality. (author). 56 refs, 2 tabs

1987-11-16

94

Impact of Educational Intervention Regarding Mosquito Borne Diseases and Their Control Measures among The Link Workers of Urban Health Centers (UHCs of Ahmedabad City  

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Full Text Available Background: In urban area link workers are playing key role in implementing anti-larval measures and behaviour change communication at community level to prevent and control mosquito borne diseases. Objectives: To check baseline knowledge of link workers regarding mosquito borne diseases and control measures and assess their knowledge 14 days after single educational interventional training. Methodology: All 274 link workers of 17 selected UHCs out of total 57 UHCs were taken as study population and their baseline knowledge regarding mosquito borne diseases and mosquito control measures was assessed by questionnaire. Single educational training for 45 minutes was given to groups of link workers and their post– intervention knowledge for same was assessed after 14 days. Mean, Wilcoxon sign-rank test were applied. Results: Mean age of link workers was 31.3 + 4.8 years. The knowledge regarding Chikungunya, Dengue and Malaria was mosquito borne diseases was respectively 55.5%, 87.9% and 95.5% which was increase after intervention to 100%. But 14.4% did not know filariasis is mosquito borne disease even after training. All link workers know about the chemical (Temephos used for mosquito control (100% but knowledge of proper temephos dose for different volume of water containers was significantly improved after intervention. The overall knowledge regarding mosquito & mosquito control measures was significantly improved after intervention (p value <0.05. Conclusion: Even though link workers were involved in anti-larval activities since from many years, many link workers had poor knowledge regarding the mosquito borne diseases and control measures.

Fancy Manish

2012-01-01

95

Guidelines to site selection for population surveillance and mosquito control trials: a case study from Mauritius.  

Science.gov (United States)

Many novel approaches to controlling mosquito vectors through the release of sterile and mass reared males are being developed in the face of increasing insecticide resistance and other limitations of current methods. Before full scale release programmes can be undertaken there is a need for surveillance of the target population, and investigation of parameters such as dispersal and longevity of released, as compared to wild males through mark-release-recapture (MRR) and other experiments, before small scale pilot trials can be conducted. The nature of the sites used for this field work is crucial to ensure that a trial can feasibly collect sufficient and relevant information, given the available resources and practical limitations, and having secured the correct regulatory, community and ethical approvals and support. Mauritius is considering the inclusion of the sterile insect technique (SIT), for population reduction of Aedes albopictus, as a component of the Ministry of Health and Quality of Life's 'Operational Plan for Prevention and Control of Chikungunya and Dengue'. As part of an investigation into the feasibility of integrating the SIT into the Integrated Vector Management (IVM) scheme in Mauritius a pilot trial is planned. Two potential sites have been selected for this purpose, Pointe des Lascars and Panchvati, villages in the North East of the country, and population surveillance has commenced. This case study will here be used to explore the considerations which go into determining the most appropriate sites for mosquito field research. Although each situation is unique, and an ideal site may not be available, this discussion aims to help researchers to consider and balance the important factors and select field sites that will meet their needs. PMID:24280144

Iyaloo, Diana P; Elahee, Khouaildi B; Bheecarry, Ambicadutt; Lees, Rosemary Susan

2014-04-01

96

Combination of a non-pyrethroid insecticide and a repellent: a new approach for controlling knockdown-resistant mosquitoes.  

Science.gov (United States)

Although pyrethroid-treated materials are a promising tool for the prevention and the control of dengue in the tropics, the development of pyrethroid resistance in the main mosquito vector (Aedes aegypti) may negate their use for personal and/or community protection. In that context, the efficacy of a mixture of a repellent (N,N-diethyl toluamide [DEET]) and a non-pyrethroid insecticide (propoxur) was investigated under laboratory conditions against both pyrethroid-susceptible and pyrethroid-resistant mosquitoes with the knockdown resistance (kdr) mutation. The results showed that a combination of propoxur and DEET induced a knockdown effect and mortality as high as deltamethrin (a standard pyrethroid) against the susceptible strain, and significantly higher efficacy against the pyrethroid-resistant strain. This could be explained mainly by the existence of a strong synergistic interaction between DEET and propoxur in mosquitoes. This study constitutes a first step towards an alternative strategy for improving mosquito control in areas with pyrethroid resistance. PMID:15964959

Pennetier, Cedric; Corbel, Vincent; Hougard, Jean-Marc

2005-06-01

97

Responses of salt marsh ecosystems to mosquito control management practices along the Atlantic Coast (U.S.A.)  

Science.gov (United States)

Open marsh water management (OMWM) of salt marshes modifies grid-ditched marshes by creating permanent ponds and radial ditches in the high marsh that reduce mosquito production and enhance fish predation on mosquitoes. It is preferable to using pesticides to control salt marsh mosquito production and is commonly presented as a restoration or habitat enhancement tool for grid-ditched salt marshes. Monitoring of nekton, vegetation, groundwater level, soil salinity, and bird communities before and after OMWM at 11 (six treatment and five reference sites) Atlantic Coast (U.S.A.) salt marshes revealed high variability within and among differing OMWM techniques (ditch-plugging, reengineering of sill ditches, and the creation of ponds and radial ditches). At three marshes, the dominant nekton shifted from fish (primarily Fundulidae species) to shrimp (Palaemonidae species) after manipulations and shrimp density increased at other treatment sites. Vegetation changed at only two sites, one with construction equipment impacts (not desired) and one with a decrease in woody vegetation along existing ditches (desired). One marsh had lower groundwater level and soil salinity, and bird use, although variable, was often unrelated to OMWM manipulations. The potential effects of OMWM manipulations on non-target salt marsh resources need to be carefully considered by resource planners when managing marshes for mosquito control.

James-Pirri, Mary-Jane; Erwin, R. Michael; Prosser, Diann J.; Taylor, Janith D.

2012-01-01

98

Mosquito control in Dar es Salaam. I. Assessment of Culex quinquefasciatus breeding sites prior to intervention.  

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In preparation for a trial polystyrene beads and pyriproxyfen for the control of Culex quinquefasciatus mosquitoes, surveys of their breeding were carried out in two contrasting areas of Dar es Salaam, Mikocheni and Ilala, during the dry season. Sanitation structures (latrines, soakage pits, septic tanks and cess pits) were the most profilic breeding places, totalling 780 in Mikocheni and 1544 in Ilala. Those in Mikocheni were estimated to contain about 1.4 times more mosquito pupae, per site, than in such structures in Ilala. This was both because a higher proportion of sites contained visible water and because sites with water were more likely to contain pupae in Mikocheni. The relative importance of the different types of structure, in terms of productivity, was the same in both areas. Although septic tanks and cess pits made up only 10.5% of the on-site sanitation structures in Ilala, they contained 53% of the total number of pupae in enclosed sites; they were therefore particularly important targets for treatment with polystyrene beads. A survey during the rainy season of sites in Ilala revealed little change in the proportion that were wet, or in the frequency of breeding in those with visible water. The number, type and area of open breeding sites varied greatly between the two study areas. In Mikocheni the area of open breeding sites was 100 times greater than in Ilala, with 97% of the 13,000 m2 being flooded grassland. In Ilala all but four of the sixty-six open breeding sites were puddles of sullage water derived from bathrooms.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7787221

Chavasse, D C; Lines, J D; Ichimori, K; Marijani, J

1995-04-01

99

Two step male release strategy using transgenic mosquito lines to control transmission of vector-borne diseases.  

Science.gov (United States)

Mosquitoes are responsible for the transmission of pathogens that cause devastating human diseases such as malaria and dengue. The current increase in mean global temperature and changing sea level interfere with precipitation frequency and some other climatic conditions which, in general, influence the rate of development of insects and etiologic agents causing acceleration as the temperature rises. The most common strategy employed to combat target mosquito species is the Integrated Vector Management (IVM), which comprises the use of multiple activities and various approaches to preventing the spread of a vector in infested areas. IVM programmes are becoming ineffective; and the global scenario is threatening, requiring new interventions for vector control and surveillance. Not surprisingly, there is a growing need to find alternative methods to combat the mosquito vectors. The possibility of using transgenic mosquitoes to fight against those diseases has been discussed over the last two decades and this use of transgenic lines to suppress populations or to replace them is still under investigation through field and laboratory trials. As an alternative, the available transgenic strategies could be improved by coupling suppression and substitution strategies. The idea is to first release a suppression line to significantly reduce the wild population, and once the first objective is reached a second release using a substitution line could be then performed. Examples of targeting this approach against vectors of malaria and dengue are discussed. PMID:24513036

Carvalho, Danilo Oliveira; Costa-da-Silva, André Luis; Lees, Rosemary Susan; Capurro, Margareth Lara

2014-04-01

100

Review of semiochemicals that mediate the oviposition of mosquitoes: a possible sustainable tool for the control and monitoring of Culicidae Revisão dos semioquímicos que mediam a oviposição em mosquitos: uma possível ferramenta sustentável para o monitoramento e controle de Culicidae  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The choice for suitable places for female mosquitoes to lay eggs is a key-factor for the survival of immature stages (eggs and larvae). This knowledge stands out in importance concerning the control of disease vectors. The selection of a place for oviposition requires a set of chemical, visual, olfactory and tactile cues that interact with the female before laying eggs, helping the localization of adequate sites for oviposition. The present paper presents a bibliographic revision on the main ...

Navarro-silva, Mario A.; Marques, Francisco A.; Jonny E. Duque L

2009-01-01

 
 
 
 
101

Why do we need alternative tools to control mosquito-borne diseases in Latin America?  

Directory of Open Access Journals (Sweden)

Full Text Available In this opinion paper, we discuss the potential and challenges of using the symbiont Wolbachia to block mosquito transmitted diseases such as dengue, malaria and chikungunya in Latin America.

Rafael Maciel-de-Freitas

2012-09-01

102

Perspectives in the control of infectious diseases by transgenic mosquitoes in the post-genomic era: a review  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Arthropod-borne diseases caused by a variety of microorganisms such as dengue virus and malaria parasites afflict billions of people worldwide imposing major economic and social burdens. Despite many efforts, vaccines against diseases transmitted by mosquitoes, with the exception of yellow fever, ar [...] e not available. Control of such infectious pathogens is mainly performed by vector management and treatment of affected individuals with drugs. However, the numbers of insecticide-resistant insects and drug-resistant parasites are increasing. Therefore, inspired in recent years by a lot of new data produced by genomics and post-genomics research, several scientific groups have been working on different strategies to control infectious arthropod-borne diseases. This review focuses on recent advances and perspectives towards construction of transgenic mosquitoes refractory to malaria parasites and dengue virus transmission.

Márcia Aparecida, Sperança; Margareth Lara, Capurro.

103

Assessing key safety concerns of a Wolbachia-based strategy to control dengue transmission by Aedes mosquitoes  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Mosquito-borne diseases such as dengue fever, chikungunya or malaria affect millions of people each year and control solutions are urgently needed. An international research program is currently being developed that relies on the introduction of the bacterial endosymbiont Wolbachia pipientis into Ae [...] des aegypti to control dengue transmission. In order to prepare for open-field testing releases of Wolbachia-infected mosquitoes, an intensive social research and community engagement program was undertaken in Cairns, Northern Australia. The most common concern expressed by the diverse range of community members and stakeholders surveyed was the necessity of assuring the safety of the proposed approach for humans, animals and the environment. To address these concerns a series of safety experiments were undertaken. We report in this paper on the experimental data obtained, discuss the limitations of experimental risk assessment and focus on the necessity of including community concerns in scientific research.

Popovici, Jean; Moreira, Luciano A; Poinsignon, Anne; Iturbe-Ormaetxe, Inaki; McNaughton, Darlene; O' Neill, Scott L.

104

Impact of Educational Intervention Regarding Mosquito Borne Diseases and Their Control Measures among The Link Workers of Urban Health Centers (UHCs) of Ahmedabad City  

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Background: In urban area link workers are playing key role in implementing anti-larval measures and behaviour change communication at community level to prevent and control mosquito borne diseases. Objectives: To check baseline knowledge of link workers regarding mosquito borne diseases and control measures and assess their knowledge 14 days after single educational interventional training. Methodology: All 274 link workers of 17 selected UHCs out of total 57 UHCs were taken as study populat...

Prajapati Arpit; Parikh Sonal,; Fancy Manish; Dv, Bala

2012-01-01

105

Review: Improving our knowledge of male mosquito biology in relation to genetic control programmes.  

Science.gov (United States)

The enormous burden placed on populations worldwide by mosquito-borne diseases, most notably malaria and dengue, is currently being tackled by the use of insecticides sprayed in residences or applied to bednets, and in the case of dengue vectors through reduction of larval breeding sites or larviciding with insecticides thereof. However, these methods are under threat from, amongst other issues, the development of insecticide resistance and the practical difficulty of maintaining long-term community-wide efforts. The sterile insect technique (SIT), whose success hinges on having a good understanding of the biology and behaviour of the male mosquito, is an additional weapon in the limited arsenal against mosquito vectors. The successful production and release of sterile males, which is the mechanism of population suppression by SIT, relies on the release of mass-reared sterile males able to confer sterility in the target population by mating with wild females. A five year Joint FAO/IAEA Coordinated Research Project brought together researchers from around the world to investigate the pre-mating conditions of male mosquitoes (physiology and behaviour, resource acquisition and allocation, and dispersal), the mosquito mating systems and the contribution of molecular or chemical approaches to the understanding of male mosquito mating behaviour. A summary of the existing knowledge and the main novel findings of this group is reviewed here, and further presented in the reviews and research articles that form this Acta Tropica special issue. PMID:24252487

Lees, Rosemary Susan; Knols, Bart; Bellini, Romeo; Benedict, Mark Q; Bheecarry, Ambicadutt; Bossin, Hervé Christophe; Chadee, Dave D; Charlwood, Jacques; Dabiré, Roch K; Djogbenou, Luc; Egyir-Yawson, Alexander; Gato, René; Gouagna, Louis Clément; Hassan, Mo'awia Mukhtar; Khan, Shakil Ahmed; Koekemoer, Lizette L; Lemperiere, Guy; Manoukis, Nicholas C; Mozuraitis, Raimondas; Pitts, R Jason; Simard, Frederic; Gilles, Jeremie R L

2014-04-01

106

Distribution of Bacillus thuringiensis subsp. israelensis in Soil of a Swiss Wetland Reserve after 22 Years of Mosquito Control?†  

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Recurrent treatments with Bacillus thuringiensis subsp. israelensis are required to control the floodwater mosquito Aedes vexans that breeds in large numbers in the wetlands of the Bolle di Magadino Reserve in Canton Ticino, Switzerland. Interventions have been carried out since 1988. In the present study, the spatial distribution of resting B. thuringiensis subsp. israelensis spores in the soil was measured. The B. thuringiensis subsp. israelensis concentration was determined in soil samples...

2011-01-01

107

Insecticide treated mosquito nets for malaria control in India-experience from a tribal area on operational feasibility and uptake  

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The study assessed the operational feasibility and acceptability of insecticide-treated mosquito nets (ITNs) in one Primary Health Centre (PHC) in a falciparum malaria endemic district in the state of Orissa, India, where 74% of the people are tribes and DDT indoor residual spraying had been withdrawn and ITNs introduced by the National Vector Borne Disease Control Programme. To a population of 63,920, 24,442 ITNs were distributed free of charge through 101 treatment centers during July-Augus...

Jambulingam, P.; Gunasekaran, K.; Ss, Sahu; Vijayakumar, T.

2008-01-01

108

Pitch control of multi-channel graded-index core polymer waveguide for optical PCB using the Mosquito method  

Science.gov (United States)

We successfully fabricate multi-channel GI circular-core polymer waveguides with precisely controlled pitches utilizing the Mosquito method. The Mosquito method is a very simple method for fabricating GI-core polymer optical waveguides that utilizes a micro dispenser. In this method, a viscous core monomer is directly dispensed into a cladding monomer layer before UV cured, and circular cores are formed by curing both the core and cladding under a UV exposure. Here, it is a concern that a needle position accuracy influences on the interchannel pitch when parallel cores are fabricated by parallel repetitive scan of a single needle. However, we succeeded in controlling the pitch with the Mosquito method and then, GI-core waveguides with 250.7+/-5.2 ?m, 126.7+/-2.6 ?m and 61.7+/-3.4 ?m are successfully fabricated for the pre-set values of 250 ?m, 125 ?m and 62.5 ?m, respectively. Then, we demonstrate a 4 × 10 Gbps transmission over the fabricated GI-core waveguide by connecting the waveguide to an MMF ribbon with a 250-?m pitch, which is realized because the pitch of the fabricated waveguide is accurately controlled to 250 ?m.

Kinoshita, Ryota; Suganuma, Daisuke; Ishigure, Takaaki

2014-03-01

109

Risk assessment for adult butterflies exposed to the mosquito control pesticide naled  

Science.gov (United States)

A prospective risk assessment was conducted for adult butterflies potentially exposed to the mosquito control insecticide naled. Published acute mortality data, exposure data collected during field studies, and morphometric data (total surface area and fresh body weight) for adult butterflies were combined in a probabilistic estimate of the likelihood that adult butterfly exposure to naled following aerial applications would exceed levels associated with acute mortality. Adult butterfly exposure was estimated based on the product of (1) naled residues on samplers and (2) an exposure metric that normalized total surface area for adult butterflies to their fresh weight. The likelihood that the 10th percentile refined effect estimate for adult butterflies exposed to naled would be exceeded following aerial naled applications was 67 to 80%. The greatest risk would be for butterflies in the family Lycaenidae, and the lowest risk would be for those in the family Hesperidae, assuming equivalent sensitivity to naled. A range of potential guideline naled deposition levels is presented that, if not exceeded, would reduce the risk of adult butterfly mortality. The results for this risk assessment were compared with other risk estimates for butterflies, and the implications for adult butterflies in areas targeted by aerial naled applications are discussed.

Bargar, Timothy A.

2012-01-01

110

Scepticism towards insecticide treated mosquito nets for malaria control in a rural community in northwestern Tanzania  

DEFF Research Database (Denmark)

Despite existence of effective tools for malaria control, malaria continues to be one of the leading killer diseases especially among under-five year children and pregnant women in poor rural populations of Sub Saharan Africa. In Tanzania Mainland the disease contributes to 39.4% of the total OPD attendances. In terms of mortality, malaria is known to be responsible for more than one third of deaths among children of age below 5 years and also contributes for up to one fifth of deaths among pregnant women. This paper is based on a study conducted in a rural community along the shores of Lake Victoria in Mwanza region, North-Western Tanzania. The study explores reasons for scepticism and low uptake of insecticide treated mosquito nets (ITNs) that were promoted through social marketing strategy for malaria control prior to the introduction of long lasting nets (LLN). The paper breaks from traditional approach that tend to study low uptake of health interventions in terms of structural practical constraints â?? cost, accessibility, everyday priorities â?? or in terms of cognition â?? insufficient knowledge of benefits e.g. ignorance of public health messages. This paper has shown that, the majority of people who could afford the prices of ITNs and who knew where to obtain the insecticides did not necessarily buy them. This suggests that, although people tend to report costrelated factors as a barrier against the use of ITNs, there are other critical concerns at work. Without underestimating the practical factors, our study have recommended to consider critical examinations of those other concerns that hinder optimal utilization of ITN for malaria control, and the basis for those concerns.

Nnko, Soori; Whyte, Susan Reynolds

2012-01-01

111

Role of cytochrome P450s in insecticide resistance: impact on the control of mosquito-borne diseases and use of insecticides on Earth  

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The fight against diseases spread by mosquitoes and other insects has enormous environmental, economic and social consequences. Chemical insecticides remain the first line of defence but the control of diseases, especially malaria and dengue fever, is being increasingly undermined by insecticide resistance. Mosquitoes have a large repertoire of P450s (over 100 genes). By pinpointing the key enzymes associated with insecticide resistance we can begin to develop new tools to aid the implementat...

David, Jean-philippe; Ismail, Hanafy Mahmoud; Chandor-proust, Alexia; Paine, Mark John Ingraham

2013-01-01

112

A six-year study of insect emergence from temporary flooded wetlands in central Sweden, with and without Bti-based mosquito control  

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In temporary wetlands in the River Dalalven floodplains, recurrent but irregular floods induce massive hatching of the flood-water mosquito Aedes sticticus, which causes enormous nuisance. Flood-water mosquito control using the biological larvicide Bacillus thuringiensis var. israelensis (Bti) was commenced in parts of the floodplains during 2002, and here we report the first six years of full-season monitoring of general insect emergence from temporary wetlands with and without treatment. Em...

Persson Vinnersten, T. Z.; Lundstrom, J. O.; Schafer, M. L.; Petersson, E.; Landin, Jan

2010-01-01

113

Indoor Use of Plastic Sheeting Impregnated with Carbamate Combined with Long-Lasting Insecticidal Mosquito Nets for the Control of Pyrethroid-Resistant Malaria Vectors  

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The combined efficacy of a long-lasting insecticidal net (LLIN) and a carbamate-treated plastic sheeting (CTPS) or indoor residual spraying (IRS) for control of insecticide-resistant mosquitoes was evaluated in experimental huts in Burkina Faso. Anopheles gambiae from the area is resistant to pyrethroids and to a lesser extent, carbamates. Relatively low mortality rates were observed with the LLIN (44%), IRS (42%), and CTPS (52%), whereas both combinations killed significantly more mosquitoes...

2010-01-01

114

Mosquito-Degradative-Potential of Cockroach and Mosquito Borne Bacteria  

Directory of Open Access Journals (Sweden)

Full Text Available The type of bacteria present on two insects (cockroach and mosquito were investigated. These microorganisms were screened for microbial control of mosquito employing their degradative ability at various microbial cell loads. The degradation of the mosquito was observed spectrophotometrically for an incubation period of 5 to 7 days. Six bacterial species (Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus, Serratia marcescens, Staphylococcus aureus and Aerobacter aerogenes were isolated from cockroach. Mosquito borne E. coli, P. aeruginosa, B. cereus and Staph. aureus. All the bacteria digested the mosquito with activity ranging from 0.02 to 1.27. Microorganisms associated with cockroach showed higher degradation activity (0.02-1.27 during the incubation than those obtained from mosquito (0.02-1.00.

F.O. Omoya

2009-01-01

115

The Potential for Genetic Control of Malaria-Transmitting Mosquitoes. Report of a Consultants Group Meeting. Working Material  

International Nuclear Information System (INIS)

Since the beginning of the Joint FAO/IAEA Division Programme on the research and development of insect pest control methodology, emphasis has been placed on the basic and applied aspects of implementing the Sterile Insect Technique (SIT). Special emphasis has always been directed at the assembly of technological progress into workable systems that can be implemented in developing countries. The general intention is to solve problems associated with insect pests that have an adverse impact on public health and the production of food and fibre. For certain insects, SIT has proven to be a powerful method for control, but for a variety of reasons this technology has not been tried on an operational scale for most of the pest species of insects that exact a toll on the endeavors of humans. The Joint FAO/IAEA Division convened a Consultants Group Meeting to examine 'The Potential for Genetic Control of Malaria-Transmitting Mosquitoes', with emphasis to be placed on the SIT. A group of five scientists met, 26-30 April 1993, to examine the current status and the future potential of genetic control for malaria mosquitoes. In most of the tropical, developing countries, and to some extent in temperate regions of the world, Anopheles mosquitoes cause havoc by transmitting malaria, a dreaded disease that causes high mortality amongst children and diminishes productivity of adults. The importance of malaria as a deterrent to further economic growth in a large part of the world cannot be over-emphasized. Malaria is a severe problem because there are inadequacies in the technology available for control. As a result of the deliberations at the meeting, the consultants prepared a list of recommendations concerning the consensus opinions about the development of genetic control for malaria vector control. This report presents the findings and recommendations of the Consultants Group Meeting.

1993-04-26

116

Why do we need alternative tools to control mosquito-borne diseases in Latin America?  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english In this opinion paper, we discuss the potential and challenges of using the symbiont Wolbachia to block mosquito transmitted diseases such as dengue, malaria and chikungunya in Latin America. [...

Maciel-de-Freitas, Rafael; Aguiar, Raquel; Bruno, Rafaela V; Guimarães, Maria Cristina; Lourenço-de-Oliveira, Ricardo; Sorgine, Marcos HF; Struchiner, Cláudio J; Valle, Denise; O' Neill, Scott L; Moreira, Luciano A.

117

Advantages of larval control for African malaria vectors: Low mobility and behavioural responsiveness of immature mosquito stages allow high effective coverage  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Based on sensitivity analysis of the MacDonald-Ross model, it has long been argued that the best way to reduce malaria transmission is to target adult female mosquitoes with insecticides that can reduce the longevity and human-feeding frequency of vectors. However, these analyses have ignored a fundamental biological difference between mosquito adults and the immature stages that precede them: adults are highly mobile flying insects that can readily detect and avoid many intervention measures whereas mosquito eggs, larvae and pupae are confined within relatively small aquatic habitats and cannot readily escape control measures. Presentation of the hypothesis We hypothesize that the control of adult but not immature mosquitoes is compromised by their ability to avoid interventions such as excito-repellant insecticides. Testing the hypothesis We apply a simple model of intervention avoidance by mosquitoes and demonstrate that this can substantially reduce effective coverage, in terms of the proportion of the vector population that is covered, and overall impact on malaria transmission. We review historical evidence that larval control of African malaria vectors can be effective and conclude that the only limitations to the effective coverage of larval control are practical rather than fundamental. Implications of the hypothesis Larval control strategies against the vectors of malaria in sub-Saharan Africa could be highly effective, complementary to adult control interventions, and should be prioritized for further development, evaluation and implementation as an integral part of Rolling Back Malaria.

Knols Bart GJ

2002-06-01

118

First Planning Meeting on Development of the Sterile Insect Techniques for Control of Malaria-Transmitting Mosquitoes  

International Nuclear Information System (INIS)

At the request of Member States a series of consultant's reports were commisioned over the past 10 years to assess the potential of developing and using the Sterile Insect Technique (SIT) for the control of vectors of malaria. The experts reports recommended that the Agency proceed with such an evaluation. The rationale for the possible inclusion of SIT into malaria vector control were detailed in these reports. All the reports emphasized that significant R and D would be required to develop and evaluate the SIT technology for mosquitoes before operational pilot projects could be initiated. Following the last of these meetings a document was prepared in which the essential R and D components were identified. This plan also included the collection of baseline data from a potential field site in Africa and the proposal that the target species should be Anopheles arabiensis. On the basis of these activities a Technical Co-operation (TC) project was developed which focused on the identification of a potential field site and provided funds for initiation of the collection of epidemiological and entomological data from the site. The R and D requirements for mosquito SIT were addressed in two ways. Firstly by undertaking limited R and D activities at the Agency's Laboratories in Seibersdorf and secondly by elaborating a Co-ordinated Research Project (CRP). The first planning meeting was thus held in Vienna from 5-8 June 2001 with representatives from Ethiopia, Mali, Namibia, Niger, Nigeria, Senegal, South Africa and Sudan; as well as experts from the UK and the USA; and a representative from the World Health Organisation (WHO). The meeting provided a forum for the participants to summarize the current malaria situation, its control and the importance of An. arabiensis in their respective countries. The outside experts complemented these presentations by dealing with specific issues. The objectives of the meeting were to: Review the status of the control of malaria-transmitting mosquitoes in Member States including Government policies; Review the state of art for possible use of SIT for the control of malaria-transmitting mosquitoes; Formulate long-term and short-term strategies and action plans for R and D aimed at possible use of SIT for the control of An. arabiensis; Identify international and regional partners and discuss modalities for co-operation.

2001-06-05

119

Development of Metarhizium anisopliae and Beauveria bassiana formulations for control of malaria mosquito larvae  

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Full Text Available Abstract Background The entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana have demonstrated effectiveness against anopheline larvae in the laboratory. However, utilising these fungi for the control of anopheline larvae under field conditions, relies on development of effective means of application as well as reducing their sensitivity to UV radiation, high temperatures and the inevitable contact with water. This study was conducted to develop formulations that facilitate the application of Metarhizium anisopliae and Beauveria bassiana spores for the control of anopheline larvae, and also improve their persistence under field conditions. Methods Laboratory bioassays were conducted to test the ability of aqueous (0.1% Tween 80, dry (organic and inorganic and oil (mineral and synthetic formulations to facilitate the spread of fungal spores over the water surface and improve the efficacy of formulated spores against anopheline larvae as well as improve spore survival after application. Field bioassays were then carried out to test the efficacy of the most promising formulation under field conditions in western Kenya. Results When formulated in a synthetic oil (ShellSol T, fungal spores of both Metarhizium anisopliae and Beauveria bassiana were easy to mix and apply to the water surface. This formulation was more effective against anopheline larvae than 0.1% Tween 80, dry powders or mineral oil formulations. ShellSol T also improved the persistence of fungal spores after application to the water. Under field conditions in Kenya, the percentage pupation of An. gambiae was significantly reduced by 39 - 50% by the ShellSol T-formulated Metarhizium anisopliae and Beauveria bassiana spores as compared to the effects of the application of unformulated spores. Conclusions ShellSol T is an effective carrier for fungal spores when targeting anopheline larvae under both laboratory and field conditions. Entomopathogenic fungi formulated with a suitable carrier are a promising tool for control of larval populations of malaria mosquitoes. Additional studies are required to identify the best delivery method (where, when and how to make use of the entomopathogenic potential of these fungi against anopheline larvae.

Takken Willem

2011-02-01

120

Comparison between diflubenzuron and a Bacillus thuringiensis israelensis- and Lysinibacillus sphaericus-based formulation for the control of mosquito larvae in urban catch basins in Switzerland.  

Science.gov (United States)

A field test was conducted to evaluate a commercial biolarvicide based on Bacillus thuringiensis var. israelensis and Lysinibacillus sphaericus to control mosquitoes breeding in catch basins in southern Switzerland. The efficacy and residual activity of the microbial mosquito larvicide applied at the recommended rate of 10 g per catch basin was compared to the currently used larvicide diflubenzuron. Both products provided a very good control activity (> 97% of reduction) of late instars (3rd and 4th instars) and pupae for 4 wk. However, only the microbial formulation controlled immature stages during the whole period of the trial, with > 98% of larval reduction. A single application of the microbial larvicide applied at 10 g per catch basin significantly reduced the number of immature mosquitoes for at least 70 days. The quantity of rainfall in the 48-h period before each sampling and the water temperature did not influence the efficacy of the treatments. Under the environmental conditions encountered in southern Switzerland, the larvicide tested may be a valid alternative to diflubenzuron to control mosquitoes in urban catch basins. The long-lasting control by the microbial larvicide further reduces the number of treatments required to keep the population of mosquitoes at low levels. PMID:23923328

Guidi, Valeria; Lüthy, Peter; Tonolla, Mauro

2013-06-01

 
 
 
 
121

Eficiencia del Galgotrin 25 EC, Terfos 48 EC, Lambdacialotrina 2,5 EC e Icon 2,5 EC en el control del mosquito Aedes aegypti en el Municipio Santiago de Cuba, Cuba Efficiency of Galgothrin 25 EC, Terfos 48 EC, Lambdacyhalothrin 2,5 EC and Icon 2,5 EC for the control of Aedes aegypti mosquitoes in Santiago de Cuba municipality  

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INTRODUCCIÓN: en las epidemias o brotes de dengue los plaguicidas químicos desempeñan un papel fundamental para controlar los mosquitos adultos transmisores de la enfermedad, y como sostén del Programa de control del vector en Cuba. OBJETIVO: se realizó una investigación para conocer la efectividad y la eficiencia de las formulaciones de insecticidas en uso en el control del mosquito Aedes aegypti en la provincia Santiago de Cuba, y así trazar las estrategias de su uso. MÉTODOS: los b...

2008-01-01

122

A five-year integrated mosquito control project in Kavala (N. Greece)  

International Nuclear Information System (INIS)

Full text: The plain of the Nestos River is a coastal area of 25,000 ha of agricultural land irrigated by the day-regulated waters of the Nestos River. Rice fields (600 individual parcels of 1,900 ha of total surface) represent the most important breeding sites during summer (five larvicide applications on average). Abandoned agricultural land (over 200 fields of 900 ha) receiving occasionally irrigation water constitutes the second most productive mosquito-breeding site (1-2 applications). Approximately 1-2% of the total surface of 6,500 ha of corn cultivation fields is poorly drained and thus about 100 ha produce at least one generation of mosquitoes during the summer. Along its 25 kilometers of seashore, the area of Nestos comprises the lagoons of Kavala (extensive aquaculture), and the last part of the delta of the Nestos River, 11,500 ha of protected wetlands under the Ramsar convention. About 2,000 ha of these wetlands harbours plants such as Arthr. fruticosum, Sal. europea, Ael. littoralis, Ju. maritimus, Sc. maritimus, representing highly productive mosquito breeding sites (1-2 generations during the summer). Ecological mapping involved 3,200 individual vegetation polygons organised in 311 different sampling stations. Larvae sampling protocol was followed on a weekly basis for the individual and/or groups of parcels in the agricultural and natural environment. All the above information was systematically monitored and transferred to an ArcView (8.3)-GIS (Geographical Information System) database for further exploitation. In addition, mosquito breeding sites were recorded in the urban environment: within 9 villages, 2,300 individual residences were monitored and 1,070 cesspools were recorded, out of which more than 50% were producing mosquitoes (1-2 applications). In total 8,500 ha were treated with larvicides by using temephos and diflubenzuron (agricultural land), Bti (natural environment) and MMF-Agnique (urban environment). 70% of the applications were made by air using a spraying helicopter (Hiller) and a specially modified ultra-light motorized (Delta type) equipped with GPS (Geographical Positioning System). During the five years of application of the project, 17 species of mosquitoes have been identified, the most important being Ochlerotatus caspius and Anopheles spp. (human bait and CO2 traps). Nuisance has been considerably reduced since the beginning of the operations, when 1,000 bites/hour were not unusual. Evaluation of the project was made twice through 200 questionnaires in year 2000 and 180 questionnaires in year 2004. Local community is fully supporting the project: 90% of the people are willing to participate financially for the continuation of the project. (author)

2005-05-09

123

History of Mosquito Releases for Control and Potential of New Molecular Capabilities  

International Nuclear Information System (INIS)

Ten different field trials, of varying sizes, have been carried out with sterile mosquitoes, the majority being in the 1970's. The major trials were in India, Burma and El Salvador. The major biological problems encountered were the failure of the sterile males to mate with the wild females and density dependent larval survival. There were also several problems associated with the technology, e.g. failures in mass rearing, inappropriate release technologies and immigration into the treatment area. New transgenic developments may offer some improvements but the above constraints will still need to be solved. Systems to genetically sterilize insects in the field are being evaluated in mosquitoes and have been shown to be successful in Drosophila. The genetic constructs used in Drosophila may well function in Anopheles.

2001-06-05

124

Mosquitoes Associated with Ditch-Plugged and Control Tidal Salt Marshes on the Delmarva Peninsula  

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A study was conducted during the summer of 2009 (from July to September) to characterize mosquito communities among different habitats in five historically ditched tidal salt marshes and three adjacent wooded areas in the E.A. Vaughn Wetland Management Area on the Maryland Delmarva Peninsula, USA. Study marshes are characteristic of Atlantic coastal salt marshes that had undergone grid ditching from the 1930s to 1950s. In the autumn of 2008 (October and November) ditches were plugged near the...

Leisnham, Paul T.; Sarah Sandoval-Mohapatra

2011-01-01

125

Control of pyrethroid-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes with chlorfenapyr in Benin  

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Objective To compare the efficacy of chlorfenapyr applied on mosquito nets and as an indoor residual spray against populations of Anopheles gambiae and Culex quinquefasciatus in an area of Benin that shows problematic levels of pyrethroid resistance. Method Eight-week trial conducted in experimental huts. Results Indoor residual spraying killed 82.9% of An. gambiae overall (mean mortality: 79.5%) compared to 53.5% overall (mean mortality: 61.7%) in the hut containing the lower dosed ITN. Anal...

2009-01-01

126

Microdroplet application of mosquitocidal Bacillus thuringiensis using ultra-low-volume generator for the control of mosquitos.  

Science.gov (United States)

In an effort to develop a more effective technique in dispersing a microbial control agent, Bacillus thuringiensis (Bt), a truck-mounted ultra low volume (ULV) generator (Scorpion) was used to disperse B. thuringiensis israelensis (Bti) and Bti with malathion. Complete larval and adult mortalities for all tested mosquito species within the first 70-80 feet from the ULV generator were achieved. Beyond that distance less than 50% mortality was achieved as insufficient sprayed particles reached the area. A minimum of 10(3) Bti colony forming units per ml is required to cause 100% larval mortality. The sprayed Bti larvicidal toxins were persistent in the test water 7 days post ULV. The effectiveness of B. thuringiensis jegathesan (Btj), a new mosquitocidal Bt serotype was also evaluated. Similar mortality results as Bti were achieved except that the Btj toxins underwent degradation in the test water, since less than 50% less in larval mortality was observed in 7 days post ULV samples. This ULV method has the potential to disperse Bt and malathion effectively for a simultaneous control of mosquito adults and larvae. PMID:9185282

Seleena, P; Lee, H L; Nazni, W A; Rohani, A; Kadri, M S

1996-09-01

127

Fermentation of a Malaysian Bacillus thuringiensis serotype H-14 isolate, a mosquito microbial control agent utilizing local wastes.  

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A screening program searching for indigenous microbial control agents of mosquitos in Malaysia is initiated since 1987 and to date at least 20 isolates of mosquitocidal Bacillus thuringiensis serotypes have been obtained. Preliminary field evaluation of several isolates indicated that they are highly effective in the control of medically important mosquito species. For operational purposes, there is an urgent need to produce this agent utilizing cheap and locally available wastes through fermentation biotechnology. Fermentation studies in shake-flasks containing standard nutrient broth and soya bean waste, respectively, indicate that it takes about 37 hours for a Malaysian isolate of B. thuringiensis serotype H-14 to mature. In the grated coconut waste, fishmeal and rice bran, the bacteria took 28 hours, 26 hours and 126 hours respectively to mature. The endotoxin was harvested from the standard nutrient broth at 55 hours and at 50 hours from soybean, grated coconut waste and fishmeal. The endotoxin could only be harvested 150 hours after inoculation from rice bran medium. However, no bacterial growth was detected in palm oil effluent. In terms of endotoxin and biomass production, fishmeal appears to be a suitable medium. Variations in the pH of the fermenting media were also noted. PMID:1948250

Lee, H L; Seleena, P

1991-03-01

128

Attractive toxic sugar baits: control of mosquitoes with the low-risk active ingredient dinotefuran and potential impacts on nontarget organisms in Morocco.  

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We evaluated the efficacy of attractive toxic sugar baits (ATSB) in the laboratory and field with the low-risk active ingredient dinotefuran against mosquito populations. Preliminary laboratory assays indicated that dinotefuran in solution with the sugar baits was ingested and resulted in high mortality of female Culex quinquefasciatus Say and Aedes aegypti Linnaeus. Field studies demonstrated >70% reduction of mosquito populations at 3 wk post-ATSB application. Nontarget feeding of seven insect orders-Hymenoptera, Lepidoptera, Coleoptera, Diptera, Hemiptera, Orthoptera, and Neuroptera-was evaluated in the field after application of attractive sugar baits (ASB) on vegetation by dissecting the guts and searching for food dye with a dissecting microscope. Nontargets were found stained with ASB 0.9% of the time when the application was applied on green nonflowering vegetation. Only two families were significantly impacted by the ASB application: Culicidae (mosquitoes) and Chironomidae (nonbiting midges) of the order Diptera. Pollinators of the other insect orders were not significantly impacted. No mortality was observed in the laboratory studies with predatory nontargets, wolf spiders or ground beetles, after feeding for 3 d on mosquitoes engorged on ATSB applied to vegetation. Overall, this novel control strategy had little impact on nontarget organisms, including pollinators and beneficial insects, and was effective at controlling mosquito populations, further supporting the development of ATSB for commercial use. PMID:24331613

Khallaayoune, Khalid; Qualls, Whitney A; Revay, Edita E; Allan, Sandra A; Arheart, Kristopher L; Kravchenko, Vasiliy D; Xue, Rui-De; Schlein, Yosef; Beier, John C; Müller, Günter C

2013-10-01

129

Genetic control of insects: Characterization of mobile genetic elements from mosquito genomes  

International Nuclear Information System (INIS)

The Juan elements constitute a family of LINE's retroposons which are dispersed in the genome of many strains, if not all, of the three mosquito species A. Aegypti, C. pipiens and C. tarsalis. A specific Juan subfamily is amplified and dispersed in the genome of each of these species. They have been designated respectively as Juan A in A. aegypti, Juan C in C. pipiens and Juan Ct in C. tarsalis. The distribution of Juan retroposons among mosquito species does not reflect the phylogeny of these species. Furthermore, the Juan retroposons form homogeneous subfamilies: full-length copies which are reiterated in strains collected from regions covering different continents are nearly identical. These data are interpreted to indicate that the Juan retroposons have spread recently in the mosquito genomes harbouring them, perhaps upon horizontal transfer from other species. Juan A elements have been found in two isolates of A. albopictus and one isolate of A. polynesiensis, whereas numerous other isolates of these two species are devoided of any Juan-like sequence. The unfrequent presence of Juan A elements in some strains of A. albopictus and A. polynesiensis can be the result of an horizontal invasion, but more probably from cross-hybridizations which have been reported sometimes to occur between the former species and A. aegypti. No progeny is obtained when A. albopictus males containing Juan A retroposons are crossed with females lacking these elements, whereas the reciprocal cross is fertile. Such results suggest that the Juan retroposons may be responsible for incompatibilities between strains. (author). 19 refs, 1 fig., 1 tab

1993-09-01

130

Determining the spatial autocorrelation of dengue vector populations: influences of mosquito sampling method, covariables, and vector control.  

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We investigated spatial autocorrelation of female Aedes aegypti L. mosquito abundance from BG-Sentinel trap and sticky ovitrap collections in Cairns, north Queensland, Australia. BG-Sentinel trap collections in 2010 show a significant spatial autocorrelation across the study site and over a smaller spatial extent, while sticky ovitrap collections only indicate a non-significant, weak spatial autocorrelation. The BG-Sentinel trap collections were suitable for spatial interpolation using ordinary kriging and cokriging techniques. The uses of Premise Condition Index and potential breeding container data have helped improve our prediction of vector abundance. Semiovariograms and prediction maps indicate that the spatial autocorrelation of mosquito abundance determined by BG-Sentinel traps extends farther compared to sticky ovitrap collections. Based on our data, fewer BG-Sentinel traps are required to represent vector abundance at a series of houses compared to sticky ovitraps. A lack of spatial structure was observed following vector control treatment in the area. This finding has implications for the design and costs of dengue vector surveillance programs. PMID:24820568

Azil, Aishah H; Bruce, David; Williams, Craig R

2014-06-01

131

An exploratory survey of malaria prevalence and people's knowledge, attitudes and practices of mosquito larval source management for malaria control in western Kenya.  

Science.gov (United States)

A large proportion of mosquito larval habitats in urban and rural communities in sub-Saharan Africa are man-made. Therefore, community-based larval source management (LSM) could make a significant contribution to malaria control in an integrated vector management approach. Here we implemented an exploratory study to assess malaria prevalence and people's knowledge, attitudes and practices on malaria transmission, its control and the importance of man-made aquatic habitats for the development of disease vectors in one peri-urban lowland and two rural highland communities in western Kenya. We implemented monthly cross-sectional malaria surveys and administered a semi-structured questionnaire in 90 households, i.e. 30 households in each locality. Malaria prevalence was moderate (3.2-6.5%) in all sites. Nevertheless, residents perceived malaria as their major health risk. Thirty-two percent (29/90) of all respondents did not know that mosquitoes are responsible for the transmission of malaria. Over two-thirds (69/90) of the respondents said that mosquito breeding site could be found close to their homes but correct knowledge of habitat characteristics was poor. Over one-third (26/67) believed that immature mosquitoes develop in vegetation. Man-made pools, drainage channels and burrow pits were rarely mentioned. After explaining where mosquito larvae develop, 56% (50/90) felt that these sites were important for their livelihood. Peri-urban residents knew more about mosquitoes' role in malaria transmission, could more frequently describe the larval stages and their breeding habitats, and were more likely to use bed nets even though malaria prevalence was only half of what was found in the rural highland sites (pbased programs that take people's needs into account. Innovative, community-based training programs need to be developed to increase people's awareness of man-made vector breeding sites and acceptable control methods need to be designed in collaboration with the communities. PMID:20399739

Imbahale, S S; Fillinger, U; Githeko, A; Mukabana, W R; Takken, W

2010-09-01

132

The entomopathogenic fungus Metarhizium anisopliae for mosquito control. Impact on the adult stage of the African malaria vector Anopheles gambiae and filariasis vector Culex quinquefasciatus  

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Insect-pathogenie fungi for mosquito control (Chapters 1-3)Malaria and lymphatic tilariasis impose serious human health burdens in the tropics. Up to 500 million cases of malaria are reported annually, resulting in an estimated 1.5-2.7million deaths, of which 90% occur in sub-Saharan Africa. Malaria is caused by protozoa of the genus Plasmodium and is transmitted through bites of mosquitoes belonging to the genus Anopheles. Lymphatic filariasis is caused by helminths, the most widespread spec...

2004-01-01

133

The Potential of the Sterile Insect Technique and other Genetic Methods for Control of Malaria-Transmitting Mosquitoes. Report of a Consultants Meeting  

International Nuclear Information System (INIS)

This report updates information provided by a 1993 consultant group on the use of genetic methods for control of malaria-transmitting mosquitoes. Human malaria parasites of the genus Plasmodium are exclusively transmitted by mosquitoes of the genus Anopheles. Where these two groups co-exist, the transmission of the parasite to humans can create a major health problem. Malaria currently causes 2 million deaths world-wide and approximately 400 million clinical cases annually. There are ca. 15 major vector species and 30-40 vectors of lesser importance. This report considers the practicality of developing the sterile insect technique (SIT) or other genetic mechanisms in order to eradicate mosquito vectors from specific areas. This would interrupt transmission and eliminate malaria in those areas.

1996-08-02

134

An update on the incidence of dengue gaining strength in Saudi Arabia and current control approaches for its vector mosquito  

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Background The cases of dengue reported earlier in the late 1990s from the Kingdom of Saudi Arabia (KSA) occurred in the cities of Jeddah and Makkah. Although the kingdom has ample financial resources to establish effective control measures for the dengue vector, numerous cases of dengue occur and fluctuate in numbers from year to year. This necessitates a serious review of the current vector control strategies being practiced in order to identify the existing shortcomings. This short report provides an update on epidemiology of dengue in KSA (specifically in cities of Jeddah and Makkah) with a critical look at the current vector control strategies. Findings In 2013, 4411 cases of dengue were reported, with 8 cases of mortality. This number of dengue incidence was four times higher compared to 2012. In 2013, the highest number of 1272 dengue cases was reported in May, while the lowest number (37) of cases was reported in September. Conclusions It is evident that the control strategies of the dengue vector presently employed are inadequate. There seems to be serious deficiencies in following proper scientific procedures during field application(s) of control materials against the vector as is evident by the increases in the number of dengue cases as well as frequent outbreaks of the vector mosquito populations. In this review, some specific suggestions are made to draw attention to the relevant KSA authorities of the possible reasons behind unsuccessful control results and as to how to improve the strategy of dengue vector control in the kingdom.

2014-01-01

135

Made-to-measure malaria vector control strategies: rational design based on insecticide properties and coverage of blood resources for mosquitoes  

Science.gov (United States)

Eliminating malaria from highly endemic settings will require unprecedented levels of vector control. To suppress mosquito populations, vector control products targeting their blood hosts must attain high biological coverage of all available sources, rather than merely high demographic coverage of a targeted resource subset, such as humans while asleep indoors. Beyond defining biological coverage in a measurable way, the proportion of blood meals obtained from humans and the proportion of bites upon unprotected humans occurring indoors also suggest optimal target product profiles for delivering insecticides to humans or livestock. For vectors that feed only occasionally upon humans, preferred animal hosts may be optimal targets for mosquito-toxic insecticides, and vapour-phase insecticides optimized to maximize repellency, rather than toxicity, may be ideal for directly protecting people against indoor and outdoor exposure. However, for vectors that primarily feed upon people, repellent vapour-phase insecticides may be inferior to toxic ones and may undermine the impact of contact insecticides applied to human sleeping spaces, houses or clothing if combined in the same time and place. These concepts are also applicable to other mosquito-borne anthroponoses so that diverse target species could be simultaneously controlled with integrated vector management programmes. Measurements of these two crucial mosquito behavioural parameters should now be integrated into programmatically funded, longitudinal, national-scale entomological monitoring systems to inform selection of available technologies and investment in developing new ones.

2014-01-01

136

Genetically Modified Mosquito: Myth and Reality  

Directory of Open Access Journals (Sweden)

Full Text Available Sterile Insect Technique (SIT has been applied successfully in some agricultural pest control programs in the past, but in many cases, success has not been sustainable in the long run. Various attempts have been made to duplicate this limited success SIT application in agriculture to other areas of applications, particularly in vector control. For example, a recent mosquito control program has been initiated in Malaysia to eliminate dengue-mosquitoes Aedes aegypti by releasing large amount of genetically modified GM male mosquitoes into the field to outcompete the wild male mosquitoes. Field experimental data that has been made available in the literature is limited, rendering it difficult to make independent assessment on its short-term efficacy and long-term sustainability of this GM control strategy. This paper presents a preliminary assessment of the effectiveness of GM mosquito in controlling dengue mosquito population by means of model simulations via DEER (Dengue Encephalitis Eradication Routines. Preliminary results indicate negative conclusion regarding the effectiveness of GM mosquitoes in controlling wild A. aegypti population over the long-term. Essentially, significant reduction of wild mosquito population is possible only if large over-flooding ratios are applied. Further, repeated releases must be maintained over an infinite time horizon to continue to sustain low population of mosquitoes. Major difficulty remains to be resolved. In particular, in-depth costbenefit analysis on this control program is essential to ensure long-term institutional and social support.

Teh Su Yean

2013-02-01

137

Mosquito age and dengue transmission  

Science.gov (United States)

This online portal features a research project funded by The Grand Challenges in Global Health Initiative to develop new strategies to control mosquitoes that transmit human disease. Specifically, the project is focused on a method to reduce dengue transmission using naturally occurring bacterial symbionts that reduce mosquito life span. The site includes a background of this work, participating research programs and researchers, project publications, current progress, news and events, and FAQs.

Initiative, The G.

138

DEET mosquito repellent sold through social marketing provides personal protection against malaria in an area of all-night mosquito biting and partial coverage of insecticide-treated nets: a case-control study of effectiveness.  

Science.gov (United States)

DEET (diethyl-3-methylbenzamide), the widely used mosquito repellent, has the potential to prevent malarial infection but hitherto there has been no study demonstrating this possibility during normal everyday use. Mosbar, a repellent soap containing DEET, was promoted through social marketing in villages in eastern Afghanistan. This was followed up with a case-control study of effectiveness against malarial infection conducted through local clinics. Mosbar was purchased by 43% of households. Reported use of insecticide-treated nets (ITNs) was 65% among the control group. There was a strong association between Mosbar use and ITN use, as 81% of Mosbar users also possessed ITN. The use of Mosbar was associated with a 45% reduction in the odds of malaria (95% CI: -11% to 72%, P=0.08) after adjusting for ITN and other unmatched factors. Ownership of ITNs was associated with a 46% reduction in the odds of malaria (95% CI: 12% to 67%, P=0.013) after adjusting for Mosbar and other unmatched factors. The greatest reduction in the odds of malaria was associated with combined use of Mosbar and ITN (69% reduction, 95% CI: 28% to 87%, P=0.007). The association between recalled use of Mosbar 10 days ago (nearer the time of infection) and reduction in malarial infections (adjusted odds ratio 0.08, 95% CI: 0.01-0.61, P=0.001) was significantly stronger than that shown by current use of Mosbar. Most purchasers of Mosbar were satisfied with the product (74%), although a minority said they preferred to use only ITN (8%). The local mosquito vectors, Anopheles stephensi and A. nigerrimus, started biting shortly after dusk and continued biting until early morning. It was shown that Mosbar prevented biting throughout this period. In regions where mosquito vectors bite during evening and night, repellents could have a useful supplementary role to ITN and their use should be more widely encouraged. PMID:14996363

Rowland, Mark; Freeman, Tim; Downey, Gerald; Hadi, Abdul; Saeed, Mohammed

2004-03-01

139

An exploratory survey of malaria prevalence and people's knowledge, attitudes and practices of mosquito larval source management for malaria control in western Kenya  

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A large proportion of mosquito larval habitats in urban and rural communities in sub-Saharan Africa are man-made. Therefore, community-based larval source management (LSM) could make a significant contribution to malaria control in an integrated vector management approach. Here we implemented an exploratory study to assess malaria prevalence and people's knowledge, attitudes and practices on malaria transmission, its control and the importance of man-made aquatic habitats for the development ...

2010-01-01

140

Large-scale use of mosquito larval source management for malaria control in Africa: a cost analysis  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background At present, large-scale use of two malaria vector control methods, long-lasting insecticidal nets (LLINs and indoor residual spraying (IRS is being scaled up in Africa with substantial funding from donors. A third vector control method, larval source management (LSM, has been historically very successful and is today widely used for mosquito control globally, except in Africa. With increasing risk of insecticide resistance and a shift to more exophilic vectors, LSM is now under re-evaluation for use against afro-tropical vector species. Here the costs of this intervention were evaluated. Methods The 'ingredients approach' was used to estimate the economic and financial costs per person protected per year (pppy for large-scale LSM using microbial larvicides in three ecologically diverse settings: (1 the coastal metropolitan area of Dar es Salaam in Tanzania, (2 a highly populated Kenyan highland area (Vihiga District, and (3 a lakeside setting in rural western Kenya (Mbita Division. Two scenarios were examined to investigate the cost implications of using alternative product formulations. Sensitivity analyses on product prices were carried out. Results The results show that for programmes using the same granular formulation larviciding costs the least pppy in Dar es Salaam (US$0.94, approximately 60% more in Vihiga District (US$1.50 and the most in Mbita Division (US$2.50. However, these costs are reduced substantially if an alternative water-dispensable formulation is used; in Vihiga, this would reduce costs to US$0.79 and, in Mbita Division, to US$1.94. Larvicide and staff salary costs each accounted for approximately a third of the total economic costs per year. The cost pppy depends mainly on: (1 the type of formulation required for treating different aquatic habitats, (2 the human population density relative to the density of aquatic habitats and (3 the potential to target the intervention in space and/or time. Conclusion Costs for LSM compare favourably with costs for IRS and LLINs, especially in areas with moderate and focal malaria transmission where mosquito larval habitats are accessible and well defined. LSM presents an attractive tool to be integrated in ongoing malaria control effort in such settings. Further data on the epidemiological health impact of larviciding is required to establish cost effectiveness.

Worrall Eve

2011-11-01

 
 
 
 
141

Controle de mosquitos com base em larvicidas no Estado do Rio Grande do Sul, Brasil: a escolha do agente de controle  

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Full Text Available Desenvolveu-se neste estudo uma comparação entre larvicidas químicos e biológicos usados em programas de controle de mosquitos no Rio Grande do Sul. Em bioensaios de laboratório contra Culex quinquefasciatus constatou-se que as formulações biológicas líquidas Vectobac 12 AS e Teknar 3000 (Bacillus thuringiensis israelensis, ABG 6262 líquido e em pó (B. sphaericus 2362, foram altamente eficazes. Também as formulações experimentais de B. thuringiensis israelensis produzidas em laboratórios brasileiros foram consideradas adequadas. Entre as formulações químicas, os compostos piretróides Pirisa e K-Othrine produziram resultados melhores do que os organo-fosforados Lebaycid e Abate. Estes últimos produziram respostas dez vezes mais fracas do que o previsto em outros estudos. Em condições de campo, a dose de 1250 mg/m² para as formulações biológicas foi considerada adequada para a rotina das aplicações, porque permite superar as influências físicas do meio sobre os resultados. Somente as formulações de B. sphaericus produziram interrupções nas reinfestações dos focos de culicídeos observados. Períodos de até 39 semanas sem reinfestações foram observados em focos naturais e de um mês sem sobrevivência foi observado em tanques, onde procedia-se a reinfestação artificial. Este estudo sugere que as alternativas biológicas devem ser consideradas em programas de controle de mosquitos. Elas podem superar os problemas de resistência e eliminação, bem como da ausência de efeito residual nas aplicações de larvicidas.

Ruas-Neto Antônio L.

1994-01-01

142

Plant extracts as potential mosquito larvicides  

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Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya ferver, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management (IMM), emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain an...

Ghosh, Anupam; Chowdhury, Nandita; Chandra, Goutam

2012-01-01

143

Bioreactor and substrate selection for solid-state cultivation of the malaria mosquito control agent Metarhizium anisopliae  

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Metarhizium anisopliae spores are a promising alternative to chemical insecticides against malaria mosquitoes. In-house application resulting in infection of mosquitoes with the fungus can strongly contribute to reducing malaria transmission. For such application, fungal spores need to be produced in large quantities. Cultivation of the fungus on several solid substrates and in two bioreactor types for solid state fermentation was studied. Our experiments showed that M. anisopliae cannot with...

Breukelen, F. R.; Haemers, S.; Wijffels, R. H.; Rinzema, A.

2011-01-01

144

The practical importance of permanent and semipermanent habitats for controlling aquatic stages of Anopheles gambiae sensu lato mosquitoes: operational observations from a rural town in western Kenya  

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Control of aquatic-stage Anopheles is one of the oldest and most historically successful interventions to prevent malaria, but it has seen little application in Africa. Consequently, the ecology of immature afrotropical Anopheles has received insufficient attention. We therefore examined the population dynamics of African anopheline and culicine mosquitoes using operationally practicable techniques to examine the relative importance and availability of different larval habitats in an area of ...

Fillinger, U.; Sonye, G.; Killeen, G. F.; Knols, B. G. J.; Becker, N.

2004-01-01

145

Cytoplasmic Incompatibility as a Means of Controlling Culex pipiens quinquefasciatus Mosquito in the Islands of the South-Western Indian Ocean  

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The use of the bacterium Wolbachia is an attractive alternative method to control vector populations. In mosquitoes, as in members of the Culex pipiens complex, Wolbachia induces a form of embryonic lethality called cytoplasmic incompatibility, a sperm-egg incompatibility occurring when infected males mate either with uninfected females or with females infected with incompatible Wolbachia strain(s). Here we explore the feasibility of the Incompatible Insect Technique (IIT), a species-specific...

2011-01-01

146

Laboratory evaluation of a Helicosporidium sp. (Protozoa: Helicosporida) as an agent for the microbial control of mosquitoes.  

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A Helicosporidium sp. isolated from diseased larvae of Culex pipiens L. in Egypt was assessed for its microbial control potential against mosquito larvae. Dose infectivity and dose mortality of the pathogen was determined for each larval instar of Cx. pipiens. Helicosporidium sp was infectious to Aedes caspius (Pallas), C. antennatus (Becker), C. perexiguus Theobald, and Culiseta longiareolata (Macquart). Using 24-hr exposures of first instar larvae to a range of concentrations between 50 and 5 x 10(3) spores/ml, Cx. antennatus and Cx. perexiguus were more susceptible than Cx. pipiens, Ae. caspius and Cs. longiareolata with LC50's of 5 x 10(2), 5 x 10(2), 1.6 x 10(3), 1.4 x 10(3), and 1.7 x 10(3), respectively. Current experiments shown that Helicosporidium spores were tolerant of freezing and storage at 5 degrees C, but not to desiccation. Production trails indicated that up to 6.2 x 10(8) spores could be routinely produced in individual cotton leaf worms, Spodoptera littolaris (Boisd) (Lepidoptera: Noctuidae). PMID:12557926

Seif, A I; Rifaat, M M

2001-04-01

147

A tool box for operational mosquito larval control: preliminary results and early lessons from the Urban Malaria Control Programme in Dar es Salaam, Tanzania  

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Full Text Available Abstract Background As the population of Africa rapidly urbanizes, large populations could be protected from malaria by controlling aquatic stages of mosquitoes if cost-effective and scalable implementation systems can be designed. Methods A recently initiated Urban Malaria Control Programme in Dar es Salaam delegates responsibility for routine mosquito control and surveillance to modestly-paid community members, known as Community-Owned Resource Persons (CORPs. New vector surveillance, larviciding and management systems were designed and evaluated in 15 city wards to allow timely collection, interpretation and reaction to entomologic monitoring data using practical procedures that rely on minimal technology. After one year of baseline data collection, operational larviciding with Bacillus thuringiensis var. israelensis commenced in March 2006 in three selected wards. Results The procedures and staff management systems described greatly improved standards of larval surveillance relative to that reported at the outset of this programme. In the first year of the programme, over 65,000 potential Anopheles habitats were surveyed by 90 CORPs on a weekly basis. Reaction times to vector surveillance at observations were one day, week and month at ward, municipal and city levels, respectively. One year of community-based larviciding reduced transmission by the primary malaria vector, Anopheles gambiae s.l., by 31% (95% C.I. = 21.6–37.6%; p = 0.04. Conclusion This novel management, monitoring and evaluation system for implementing routine larviciding of malaria vectors in African cities has shown considerable potential for sustained, rapidly responsive, data-driven and affordable application. Nevertheless, the true programmatic value of larviciding in urban Africa can only be established through longer-term programmes which are stably financed and allow the operational teams and management infrastructures to mature by learning from experience.

Govella Nico J

2008-01-01

148

Oral toxicity of Bacillus thuringiensis subsp. israelensis to adult mosquitoes.  

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The solubilized entomotoxin of Bacillus thuringiensis subsp. israelensis killed adult male and female mosquitoes of several genera and of various physiological states when it was administered orally. Adult mosquito mortality was further influenced when the preparation was contained in sucrose solution. The potential implication for the control of adult mosquitoes is discussed.

1984-01-01

149

Efficacy of Mosquito Traps for Collecting Potential West Nile Mosquito Vectors in a Natural Mediterranean Wetland  

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Surveillance, research, and control of mosquito-borne diseases such as West Nile virus require efficient methods for sampling mosquitoes. We compared the efficacy of BG-Sentinel and Centers for Disease Control and Prevention (CDC)-CO2 traps in terms of the abundances of host-seeking and blood-fed female mosquitoes and the origin of mosquito bloodmeals. Our results indicate that BG-Sentinel traps that use CO2 and attractants are as effective as CDC-CO2 traps for Cule...

2012-01-01

150

Efficacy of four insect repellents against mosquito bites: a double-blind randomized placebo-controlled field study in Senegal.  

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Insect-borne diseases represent a worldwide threat. In addition to fight against vectors (insecticides) and disease prevention (vaccination against yellow fever, chemoprophylaxis against malaria), insect repellents applied on the skin could help reduce the heavy burden related to these diseases. In a field study performed in Senegal, we compared the efficacy of one skin application between 3 and 4 p.m. of four spray repellents [icaridine 20%, para-menthane-diol (PMD) 20% and 50% and DEET 50%] against placebo, among 100 healthy male and female volunteers experienced with mosquito capture. Double-blind randomized cross-over placebo-controlled study (Latin-square design) during five consecutive nights (7 p.m. to midnight) in two villages was conducted. To avoid residual effect, right or left leg was alternately exposed during consecutive nights and the exposed leg was washed before next night. The statistical model was random and mixed effects ANOVA. All four active repellents provided a significant and similar protection compared with placebo, lasting 8 h. However, there was a non-significant trend for a higher protection by DEET 50% than by PMD 20% (P = 0.07). Duration of protection was similar for all repellents. Their effects were similar among men and women, and against Anopheles or other species. No serious adverse drug reaction was noticed. Using a rigorous methodology and a large number of volunteers, our well-controlled study demonstrated an important and similar protective effect of all four repellents compared with placebo. Such field studies should be required before approval of any newly developed repellent. PMID:19744033

Uzzan, Bernard; Konate, Lassana; Diop, Abdoulaye; Nicolas, Patrick; Dia, Ibrahima; Dieng, Yémou; Izri, Arezki

2009-10-01

151

Fluxes of terrestrial and aquatic carbon by emergent mosquitoes: a test of controls and implications for cross-ecosystem linkages.  

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Adult aquatic insects are a common resource for many terrestrial predators, often considered to subsidize terrestrial food webs. However, larval aquatic insects themselves consume both aquatic primary producers and allochthonous terrestrial detritus, suggesting that adults could provide aquatic subsidy and/or recycled terrestrial energy to terrestrial consumers. Understanding the source of carbon (aquatic vs. terrestrial) driving aquatic insect emergence is important for predicting magnitude of emergence and effects on recipient food web dynamics; yet direct experimental tests of factors determining source are lacking. Here, we use Culex mosquitoes in experimental pools as an exemplar to test how variation in general factors common to aquatic systems (terrestrial plant inputs and light) may alter the source and amount of energy exported to terrestrial ecosystems in adult aquatic insects that rely on terrestrial resources as larvae. We found strong sequential effects of terrestrial plant inputs and light on aquatic insect oviposition, diet, and emergence of Culex mosquitoes. Ovipositing mosquitoes laid ~3 times more egg masses in high terrestrial input pools under low light conditions. This behavior increased adult emergence from pools under low light conditions; however, high input pools (which had the highest mosquito densities) showed low emergence rates due to density-dependent mortality. Mosquito diets consisted mainly of terrestrial resources (~70-90 %). As a result, the amount of aquatic carbon exported from pools by mosquitoes during the experiment was ~18 times higher from low versus high light pools, while exports of terrestrial carbon peaked from pools receiving intermediate levels of inputs (3-6 times higher) and low light (~6 times higher). Our results suggest that understanding the interplay among terrestrial plant inputs, light availability and biotic responses of aquatic insects may be key in predicting source and magnitude of emergence, and thus the strength and effects of aquatic-terrestrial linkages in freshwater systems. PMID:22707036

Kraus, Johanna M; Vonesh, James R

2012-12-01

152

Survey of Bancroftian filariasis infection in humans and Culex mosquitoes in the western Brazilian Amazon region: implications for transmission and control  

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Full Text Available SciELO Brazil | Language: English Abstract in english Introduction The aim of this work was to identify possible lymphatic filariasis foci in the western Brazilian Amazonian that could be established from the reports of Rachou in the 1950s. The study was conducted in three cities of the western Brazilian Amazon region - Porto Velho and Guaja [...] rá-Mirim (State of Rondônia) and Humaitá (State of Amazonas). Methods For human infection evaluation thick blood smear stained with Giemsa was used to analyze samples collected from 10pm to 1am. Polymerase chain reaction (PCR) was used to examine mosquito vectors for the presence of Wuchereria bancrofti DNA. Humans were randomly sampled from night schools students and from inhabitants in neighborhoods lacking sanitation. Mosquitoes were collected from residences only. Results A total 2,709 night students enrolled in the Program for Education of Young Adults (EJA), and 935 people registered in the residences near the schools were examined, being 641 from Porto Velho, 214 from Guajará-Mirim and 80 from Humaitá. No individual examined was positive for the presence of microfilariae in the blood stream. A total of 7,860 female Culex quinquefasciatus specimens examined were negative by PCR. Conclusions This survey including human and mosquito examinations indicates that the western Amazon region of Brazil is not a focus of Bancroftian filariasis infection or transmission. Therefore, there is no need to be included in the Brazilian lymphatic filariasis control program.

Rodolfo Luís, Korte; Gilberto, Fontes; Juliana de Souza Almeida Aranha, Camargo; Eliana Maria Maurício da, Rocha; Edicarlos André Cavalcante de, Araújo; Marcelo Zagonel de, Oliveira; Rafael Vital dos, Santos; Luís Marcelo Aranha, Camargo.

153

Toxicological effects of prolonged and intense use of mosquito coil emission in rats and its implications on malaria control / Efectos toxicológicos del uso prolongado e intenso de emisiones de espirales contra mosquitos en ratas y sus implicaciones sobre el control de la malaria  

Scientific Electronic Library Online (English)

Full Text Available SciELO Costa Rica | Language: English Abstract in spanish Las espirales contra los mosquitos se utilizan en los países de bajos ingresos como una opción para prevenir la malaria controlando el vector de esta enfermedad. A pesar de que algunos estudios han abordado este tema, se requiere más investigación para incrementar el conocimiento sobre los efectos a [...] dversos en la salud, causados por el uso prolongado de las espirales. En este estudio se investigaron los efectos toxicológicos de los gases de las espirales a partir de dos insecticidas fabricados en el país (con piretroides: transflutrina y d-aletrina como ingredientes activos) en machos de ratas albinas. Para esto, se registraron los índices hematológicos y bioquímicos, y se hicieron evaluaciones histopatológicas y de mutagenicidad en ratas expuestas a los gases de las espirales durante períodos de 2, 4, 8, 12 y 16 semanas. La determinación hematológica se realizó mediante un analizador de hematología automatizado para determinar el conteo de los Glóbulos Blancos (WBC), el Hematocrito (PCV), Glóbulos Rojos (RBC) y las Plaquetas (PLT), mientras que las evaluaciones bioquímicas se determinaron utilizando kits comerciales disponibles. Los cambios histopatológicos fuertes se estudiaron en el riñón, el hígado y los pulmones de ratas sacrificadas. Las anormalidades en la cabeza de los espermatozoides de las ratas se utilizaron para evaluar la mutagenicidad. El humo de las espirales contra los mosquitos producen un aumento significativo (p Abstract in english Efectos toxicológicos del uso prolongado e intenso de emisiones de espirales contra mosquitos en ratas y sus implicaciones sobre el control de la malaria. Mosquito coil is a vector control option used to prevent malaria in low income counties, while some studies have addressed this issue, additional [...] reseach is required to increase knowledge on the adverse health effects caused by the prolonged use of coils. In this study we investigated the toxicological effects of fumes from two locally manufactured mosquito coil insecticides (with pyrethroids: transfluthrin and d-allethrin as active ingredients) on male albino rats. For this, we recorded the haematological and biochemical indices, and made histopathology and mutagenicity evaluations in rats exposed to mosquito fumes during 2, 4, 8, 12 and 16 week periods. Haematological determination was performed using automated hematology analyzer to determine White Blood Cell (WBC), Packed Cell Volume (PCV), Red Blood Cell (RBC) and Platelet (PLT) counts, while biochemical evaluations were determined using available commercial kits. Gross histopathological changes were studied for the kidney, liver and lungs in sacrificed rats. The rat sperm head abnormalities assessment was used to evaluate mutagenicity. Mosquito coil fumes produced significant increase (P

Taiwo Idowu, Emmanuel; Aimufua, Oyenmwen Judith; Yomi-Onilude, Ejovwoke; Akinsanya, Bamidele; Adetoro Otubanjo, Olubumi.

154

Biological control of container-breeding mosquitoes, Aedes albopictus and Culex quinquefasciatus, in a Japanese island by release of Toxorhynchites splendens adults.  

Science.gov (United States)

To control container-breeding mosquitoes in the small island of Minnajima (0.56 km2), northern Okinawa, Japan, laboratory-reared adults (aged 7-10 days) of Toxorhynchites splendens (Palawan strain), a mosquito with predatory larvae, were released repeatedly during 1984, 1986 and 1987. Thirteen species of mosquitoes (Diptera: Culicidae) occurred in artificial containers, ground pools or crab-holes on the island, the predominant species being Aedes (Stegomyia) albopictus and Culex (Culex) quinquefasciatus. Predatory mosquito larvae of Culex (Lutzia) fuscanus and Cx (Lt.) halifaxii were found commonly in wet containers. In the first year of study, during a period of 54 days from 13 May to 5 July 1984, totals of 879 female and 806 male adults of Tx.splendens were released on six occasions. Similarly, between 29 April and 30 August 1986, totals of 2920 female and 2878 male adult Tx.splendens were released. In the third study year, totals of 2041 female and 1783 male Tx.splendens were released on eight occasions during 199 days from 23 April to 7 November 1987. After adult releases at two sites, the immature stages of Tx.splendens were found in 164 out of 502 traps in 1984, 421 out of 933 traps in 1986, and 151 out of 502 traps in 1987. The number of immatures of Tx.splendens present in each trap varied from 1 to 40 in 1984, 1 to 29 in 1986 and 1 to 9 in 1987. Numbers of immatures of the target species found in the traps during August-September averaged 71.9/trap/month in 1984, 114.7/trap/month in 1986 and 36.0/trap/month in 1987, significantly less in the traps with Tx.splendens than in those without them. The present field studies indicated that, in this small island, approximately 250 adult female and 200 male Tx.splendens per month should be released from April to November, and the releases should be carried out every year, in order to control effectively the target mosquitoes Ae.albopictus and Cx quinquefasciatus breeding in artificial containers in Minnajima. PMID:1358271

Miyagi, I; Toma, T; Mogi, M

1992-07-01

155

Development of Metarhizium anisopliae and Beauveria bassiana formulations for control of malaria mosquito larvae  

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Background The entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana have demonstrated effectiveness against anopheline larvae in the laboratory. However, utilising these fungi for the control of anopheline larvae under field conditions, relies on development of effective means of application as well as reducing their sensitivity to UV radiation, high temperatures and the inevitable contact with water. This study was conducted to develop formulations that facilitate the applic...

Bukhari, S. T.; Takken, W.; Koenraadt, C. J. M.

2011-01-01

156

Free flight of the mosquito Aedes aegypti  

CERN Multimedia

High speed video observations of free flying male Aedes aegypti mosquitoes, the dengue and yellow fever vector, along with custom measurement methods, enable measurement of wingbeat frequency, body position and body orientation of mosquitoes during flight. We find these mosquitoes flap their wings at approximately 850 Hz. We also generate body yaw, body pitch and wing deviation measurements with standard deviations of less than 1 degree and find that sideways velocity and acceleration are important components of mosquito motion. Rapid turns involving changes in flight direction often involve large sideways accelerations. These do not correspond to commensurate changes in body heading, and the insect's flight direction and body heading are decoupled during flight. These findings call in to question the role of yaw control in mosquito flight. In addition, using orientation data, we find that sideways accelerations are well explained by roll-based rotation of the lift vector. In contrast, the insect's body pitch...

Iams, S M

2012-01-01

157

Diversity and function of bacterial microbiota in the mosquito holobiont.  

Science.gov (United States)

Mosquitoes (Diptera: Culicidae) have been shown to host diverse bacterial communities that vary depending on the sex of the mosquito, the developmental stage, and ecological factors. Some studies have suggested a potential role of microbiota in the nutritional, developmental and reproductive biology of mosquitoes. Here, we present a review of the diversity and functions of mosquito-associated bacteria across multiple variation factors, emphasizing recent findings. Mosquito microbiota is considered in the context of possible extended phenotypes conferred on the insect hosts that allow niche diversification and rapid adaptive evolution in other insects. These kinds of observations have prompted the recent development of new mosquito control methods based on the use of symbiotically-modified mosquitoes to interfere with pathogen transmission or reduce the host life span and reproduction. New opportunities for exploiting bacterial function for vector control are highlighted. PMID:23688194

Minard, Guillaume; Mavingui, Patrick; Moro, Claire Valiente

2013-01-01

158

A rapid knockdown effect of Penicillium citrinum for control of the mosquito Culex quinquefasciatus in Thailand.  

Science.gov (United States)

Twenty local isolates of entomopathogenic fungi were determined for control of the larvae and adults of Culex quinquefasciatus. In a laboratory experiment, a Penicillium sp. CM-010 caused 100% mortality of third-instar larvae within 2 h using a conidial suspension of 1 × 10? conidia ml?¹. Its LC?? was 3 × 10? conidia ml?¹, and the lethal time (LT??) was 1.06 h. Cloning and sequencing of its internal transcribed spacer region indicated that this Penicillium species is Penicillium citrinum (100% identity in 434 bp). Mortality of the adult was highest with Aspergillus flavus CM-011 followed with Metarhizium anisopliae CKM-048 from 1 × 10? conidia ml?¹. P. citrinum CM-010 at 1 × 10? conidia ml?¹ killed 100% larvae within 2 h while Bacillus thuringiensis var. israelensis at 5 ITU ml?¹ required 24 h. This P. citrinum CM-010 also greatly reduced survival of C. quinquefasciatus larvae in an unreplicated field test. Light and transmission electron micrographs showed that the fungal conidia were ingested by the larvae and deposited in the gut. The metabolite patulin was produced by P. citrinum CM-010 instead of citrinin. PMID:24078109

Maketon, Monchan; Amnuaykanjanasin, Alongkorn; Kaysorngup, Achirayar

2014-02-01

159

A systematic review of mosquito coils and passive emanators: defining recommendations for spatial repellency testing methodologies  

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Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propos...

2012-01-01

160

A Systematic Review of Mosquito Coils and Passive Emanators: Defining Recommendations for Spatial Repellency Testing Methodologies.  

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Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propos...

2012-01-01

 
 
 
 
161

A systematic review of mosquito coils and passive emanators: defining recommendations for spatial repellency testing methodologies  

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Abstract Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector co...

2012-01-01

162

Diving beetle assemblages of flooded wetlands in relation to time, wetland type and Bti-based mosquito control  

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We investigated the abundance and taxonomic composition of the aquatic predatory insect fauna, with focus on adult diving beetles (Coleoptera: Dytiscidae), in eight temporary flooded wet meadows and two alder swamps in the River Dalälven floodplains, central Sweden from 2002 to 2006. Diving beetles are generalist predators and often abundant in various waters, including temporary wetlands. In the River Dalälven floodplains, recurrent floods induce massive hatching of flood-water mosquitoes ...

Persson Vinnersten, Thomas Z.; Lundstro?m, Jan O.; Petersson, Erik; Landin, Jan

2009-01-01

163

Micro-lipid-droplet encapsulation of Bacillus thuringiensis subsp. israelensis delta-endotoxin for control of mosquito larvae.  

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The crystal delta-endotoxin of Bacillus thuringiensis subsp. israelensis is less toxic to larvae of Anopheles freeborni than to larvae of Aedes aegypti. However, when solubilized crystal was used, larvae from both species showed similar sensitivities. This effect presumably was due to the differences in feeding behavior between the two mosquito larvae when crystal preparations are used. A procedure is described whereby both crystal and solubilized B. thuringiensis subsp. israelensis toxin wer...

1985-01-01

164

An innovative mosquito trap for testing attractants.  

Science.gov (United States)

We describe a simple trap modification for testing volatile attractants to collect flying mosquitoes. The trap uses a standard Centers for Disease Control and Prevention trap modified for release of test chemicals. Test chemicals and other materials can be added and removed easily without spills or cross contamination. In preliminary studies using lactic acid and octenol, modified traps collected 40% more mosquitoes than controls (n = 164 and n = 117, respectively). Modifications cost less than $2.00 per trap. PMID:22533089

Dees, William H; Sylvester, Terry L; Clark, Benjamin M; Canning, Linda D; Schultz, George W; Kline, Daniel L

2012-03-01

165

Comparación morfológica e histológica del tubo digestivo de Gambusia puncticulata y Girardinus metallicus (Cyprinodontiformes: Poeciliidae), peces utilizados en el control biológico de mosquitos  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Se describió y comparó la morfología e histología del tubo digestivo de Gambusia puncticulata y Girardinus metallicus, peces utilizados en el control biológico de larvas de mosquitos en Cuba, y se relacionó con los hábitos alimentarios de cada especie. Gambusia puncticulata tiene un intestino corto [...] y grueso, característico de las especies carnívoras y Girardinus metallicus posee un intestino alargado y delgado arrollado en forma de espiral como corresponde a los peces omnívoros. Se observó que el patrón histológico del intestino en ambas especies es muy simple, sin embargo, Gambusia puncticulata presentó gran cantidad de microvellosidades de tipo ramificadas, al compararla con Girardinus metallicus, lo que aumenta de esta forma el rendimiento digestivo de su relativamente más corto, tubo digestivo. Abstract in english The morphology and histology of the digestive tract of Gambusia puncticulata and Girardinus metallicus fishes used in the biological control of mosquito larvae in Cuba, were described and compared. They were related to the food habits of each species. Gambusia puncticulata has a short and thick inte [...] stine, which is characteristic of the carnivorous species, whereas Girardinus metallicus has an elongate and thin spiral rolled up intestine as it corresponds to the omnivorous fishes. It was observed that the histological pattern of the intestine in both species is very simple; however, Gambusia puncticulata presented a great number of ramified microhairiness on comparing it with Girardinus metallicus, which increases this way the digestive yield of its relatively shorter digestive tract.

Rodríguez Rodríguez, Jinnay; González, Efraín; Hernández Contreras, Natividad; Capó, Virginia; García, Israel.

166

Comparación morfológica e histológica del tubo digestivo de Gambusia puncticulata y Girardinus metallicus (Cyprinodontiformes: Poeciliidae, peces utilizados en el control biológico de mosquitos  

Directory of Open Access Journals (Sweden)

Full Text Available Se describió y comparó la morfología e histología del tubo digestivo de Gambusia puncticulata y Girardinus metallicus, peces utilizados en el control biológico de larvas de mosquitos en Cuba, y se relacionó con los hábitos alimentarios de cada especie. Gambusia puncticulata tiene un intestino corto y grueso, característico de las especies carnívoras y Girardinus metallicus posee un intestino alargado y delgado arrollado en forma de espiral como corresponde a los peces omnívoros. Se observó que el patrón histológico del intestino en ambas especies es muy simple, sin embargo, Gambusia puncticulata presentó gran cantidad de microvellosidades de tipo ramificadas, al compararla con Girardinus metallicus, lo que aumenta de esta forma el rendimiento digestivo de su relativamente más corto, tubo digestivo.The morphology and histology of the digestive tract of Gambusia puncticulata and Girardinus metallicus fishes used in the biological control of mosquito larvae in Cuba, were described and compared. They were related to the food habits of each species. Gambusia puncticulata has a short and thick intestine, which is characteristic of the carnivorous species, whereas Girardinus metallicus has an elongate and thin spiral rolled up intestine as it corresponds to the omnivorous fishes. It was observed that the histological pattern of the intestine in both species is very simple; however, Gambusia puncticulata presented a great number of ramified microhairiness on comparing it with Girardinus metallicus, which increases this way the digestive yield of its relatively shorter digestive tract.

Jinnay Rodríguez Rodríguez

2004-04-01

167

Efficacy of a mermithid nematode Romanomermis iyengari (Welch) (Nematoda: Mermithidae) in controlling tree hole-breeding mosquito Aedes albopictus (Skuse) (Diptera: Culicidae) in a rubber plantation area of Kerala, India.  

Science.gov (United States)

In rubber plantations, tree holes are one of the major types of breeding habitats of Aedes mosquitoes which transmit dengue and chikungunya. A mermithid nematode, Romanomermis iyengari, was evaluated in tree holes for its efficacy in controlling Aedes albopictus. Infection of mosquito larvae by the nematode was determined through microscopic examination on the next day of application, and evaluation of immature density of mosquito was done on the seventh day. After application of the infective stage of the nematode in a host-parasite ratio of 1:3 or 1:4, the infection rates on the different larval instars of mosquito were similar, 85.7-95.8 % in first to third instars and 79.3 % in fourth instar larvae or 100 and 92.9 %, respectively. Parasite burden varied from 1.1 to 2.4, respectively, among first and third instar larvae applied at 1:3. At 1:4, the parasite burden was between 1.6 (fourth instar) and 4 (second instar). The increase in parasite burden due to parasite density was significant in all the larval instars (P?rubber tree hole habitats. In the nematode-applied tree holes, there was a significant level (P?mosquito and controlling pupal emergence. PMID:23306387

Paily, K P; Chandhiran, K; Vanamail, P; Kumar, N Pradeep; Jambulingam, P

2013-03-01

168

Spatiotemporal monitoring of floodwater mosquito dispersal in Osijek, Croatia.  

Science.gov (United States)

This paper demonstrates the possibility of using geostatistics to monitor the dispersal of mosquitoes for mosquito control programs at the municipal level. The case study objective was to quantify the dispersal of floodwater mosquitoes from the natural marshland Kopacki rit into the city of Osijek, Croatia, and to analyze the main factors controlling it. Fifty thousand adult Aedes vexans, Ochlerotatus sticticus, and Ochlerotatus caspius mosquitoes were marked with a powdered fluorescent pigment and released from the southern part of Kopacki rit on April 28, 2004. Forty CO2-baited Centers for Disease Control and Prevention traps were set in the area of the municipality of Osijek (171 km2) and were monitored for 10 days. A total of 582,471 mosquitoes were captured and examined in the laboratory. The mosquito counts from different sites were then interpolated using ordinary kriging and visualized dynamically to detect the dominant migrational directions. Mosquito dispersal and frequency were greatly influenced by wind speed (r = 0.82). The marked mosquitoes were found at 12 sites located from 1 km to 11.7 km away from the release point. The recapture rate was 0.044% (54% Oc. sticticus, 32% Ae. vexans, and 14% Oc. caspius). Based on the Lincoln index, the estimated total population size for floodwater mosquitoes in the study area ranged from 875 million to 2.0 billion mosquitoes. Limitations of the approach, recommendations for the improvement of the monitoring network, and spatial predictions are further discussed. PMID:17847840

Bogojevi?, Mirta Sudari?; Hengl, Tomislav; Merdi?, Enrih

2007-06-01

169

Preliminary evaluation of mosquito larvicidal efficacy of plant extracts  

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Mosquitoes are the most important single group ofinsects in terms of public health importance, whichtransmit a number of diseases, such as malaria, filariasis,dengue, Japanese encephalitis, etc. causing millionsof deaths every year. Repeated use of syntheticinsecticides for mosquito control has disrupted naturalbiological control systems and led to resurgencesin mosquito populations. It has also resulted in thedevelopment of resistance1, undesirable effects onnon-target organisms and fostered...

2007-01-01

170

Ecology of mosquitoes of Midwestern Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available Background & objectives: The ecology and distribution of various mosquito species is important inthe determination of mosquito vector abundance and associated diseases prevalence. The distributionof various mosquito genera in natural and artificial habitats and their relative species abundancewas studied between August 2002 and July 2003 in three foci (Uromi, Ekpoma and Auchi comprisingthe Esan and Etsako regions of Midwestern Nigeria.Methods: Sampling was carried out by the method of Hopkins (1952 by dipping using a pipette orladle depending on container types. Pooled contents of smaller containers were sampled with a pondnet. All breeding sources of mosquito larvae were grouped into five (5 depending on their nature,constitution and the physiochemical properties. Artificial mosquito cultures were also carried out infour different container types; plastics, metal cans, earthenware pots and bamboo strips, in parts oftwo different macro habitats subdivided into area of high human activities (AHHA and areas ofderived/secondary vegetation (ADSV. Environmental temperatures, rainfall and relative humiditywere monitored during the study.Results: The present study revealed 17 mosquito species belonging to three genera (Anopheles,Culex and Aedes which are potential vectors of four human diseases in the areas surveyed. A total of736 mosquito larvae were encountered in artificial sources and 568 larvae were harvested from naturalsources. Pools, plastics and metal cans were the predominant artificial sources of mosquito larvae.Conclusion: The contribution of human activities and increasing environmental modification to thebreeding of human disease vector mosquitoes is of importance and selective vector control measuresincluding larviciding are recommended particularly before onset of rainy season

Godwin R.A. Okogun, Jude C. Anosike, Anthony N. Okere & Bethran E.B. Nwoke

2005-03-01

171

Eficiencia del Galgotrin 25 EC, Terfos 48 EC, Lambdacialotrina 2,5 EC e Icon 2,5 EC en el control del mosquito Aedes aegypti en el Municipio Santiago de Cuba, Cuba / Efficiency of Galgothrin 25 EC, Terfos 48 EC, Lambdacyhalothrin 2,5 EC and Icon 2,5 EC for the control of Aedes aegypti mosquitoes in Santiago de Cuba municipality  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish INTRODUCCIÓN: en las epidemias o brotes de dengue los plaguicidas químicos desempeñan un papel fundamental para controlar los mosquitos adultos transmisores de la enfermedad, y como sostén del Programa de control del vector en Cuba. OBJETIVO: se realizó una investigación para conocer la efectividad [...] y la eficiencia de las formulaciones de insecticidas en uso en el control del mosquito Aedes aegypti en la provincia Santiago de Cuba, y así trazar las estrategias de su uso. MÉTODOS: los bioensayos se realizaron de acuerdo con la metodología de la OMS. Se comparó la eficacia y eficiencia entre los tratamientos de nebulizacion en frío y los de termonebulizacion con los insecticidas estudiados, mediante una prueba U de Mann Whitney. El análisis comparativo de la eficiencia entre tratamientos y cada formulación se realizó mediante una prueba de Kruskal-Wallis. RESULTADOS: al comparar las mortalidades obtenidas con ambos tratamientos se demostró que existe una diferencia altamente significativa entre ellos a favor de los tratamientos de termonebulización, lo que demuestra la eficacia de este último y su eficiencia (efectividad/costo). CONCLUSIONES: con la prueba de Kruskal-Wallis se demostró que existe una diferencia altamente significativa entre las formulaciones a favor del Galgotrin 25 EC, que es más eficiente sin DDVP. Abstract in english INTRODUCTION: In dengue epidemics or outbreaks, insecticides play an important role in controlling adult mosquitoes and in supporting the vector control program in Cuba. OBJECTIVE: To find out the effectiveness and efficiency of insecticidal formulae for Aedes aegypti mosquito control in Santiago de [...] Cuba province and to draw up the strategies for use. METHODS: Bioassays were performed according to the WHO methodology. The efficacy and efficiency of cold fogging and thermal fogging methods were compared through Mann Whitney´s U test. The comparative analysis of the efficiency of both methods and every formulation was made using Kruskal-Wallis test. RESULTS: When comparing the mortality indexes from both methods, it was observed that there was a highly significant difference between them, being the thermal fogging method the most useful because of its efficacy and efficiency (cost effectiveness). CONCLUSIONS: Kruskal-Wallis test proved that there is a highly significant difference among the various formulations. Galgothrin 25 EC is the most favourable and efficient without DDVP.

Domingo, Montada Dorta; Ivón, Calderón Morales; Daisy, Figueredo Sánchez; Eugenio, Soto Cisneros; Maureen, Leyva Silva.

172

Eficiencia del Galgotrin 25 EC, Terfos 48 EC, Lambdacialotrina 2,5 EC e Icon 2,5 EC en el control del mosquito Aedes aegypti en el Municipio Santiago de Cuba, Cuba Efficiency of Galgothrin 25 EC, Terfos 48 EC, Lambdacyhalothrin 2,5 EC and Icon 2,5 EC for the control of Aedes aegypti mosquitoes in Santiago de Cuba municipality  

Directory of Open Access Journals (Sweden)

Full Text Available INTRODUCCIÓN: en las epidemias o brotes de dengue los plaguicidas químicos desempeñan un papel fundamental para controlar los mosquitos adultos transmisores de la enfermedad, y como sostén del Programa de control del vector en Cuba. OBJETIVO: se realizó una investigación para conocer la efectividad y la eficiencia de las formulaciones de insecticidas en uso en el control del mosquito Aedes aegypti en la provincia Santiago de Cuba, y así trazar las estrategias de su uso. MÉTODOS: los bioensayos se realizaron de acuerdo con la metodología de la OMS. Se comparó la eficacia y eficiencia entre los tratamientos de nebulizacion en frío y los de termonebulizacion con los insecticidas estudiados, mediante una prueba U de Mann Whitney. El análisis comparativo de la eficiencia entre tratamientos y cada formulación se realizó mediante una prueba de Kruskal-Wallis. RESULTADOS: al comparar las mortalidades obtenidas con ambos tratamientos se demostró que existe una diferencia altamente significativa entre ellos a favor de los tratamientos de termonebulización, lo que demuestra la eficacia de este último y su eficiencia (efectividad/costo. CONCLUSIONES: con la prueba de Kruskal-Wallis se demostró que existe una diferencia altamente significativa entre las formulaciones a favor del Galgotrin 25 EC, que es más eficiente sin DDVP.INTRODUCTION: In dengue epidemics or outbreaks, insecticides play an important role in controlling adult mosquitoes and in supporting the vector control program in Cuba. OBJECTIVE: To find out the effectiveness and efficiency of insecticidal formulae for Aedes aegypti mosquito control in Santiago de Cuba province and to draw up the strategies for use. METHODS: Bioassays were performed according to the WHO methodology. The efficacy and efficiency of cold fogging and thermal fogging methods were compared through Mann Whitney´s U test. The comparative analysis of the efficiency of both methods and every formulation was made using Kruskal-Wallis test. RESULTS: When comparing the mortality indexes from both methods, it was observed that there was a highly significant difference between them, being the thermal fogging method the most useful because of its efficacy and efficiency (cost effectiveness. CONCLUSIONS: Kruskal-Wallis test proved that there is a highly significant difference among the various formulations. Galgothrin 25 EC is the most favourable and efficient without DDVP.

Domingo Montada Dorta

2008-04-01

173

Toxicity of aqueous crude neem leaf extract against culex mosquitoes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Prevention of mosquitoes from biting is one of the major problems in the world. Mosquitoes transmitting serious human diseases and causing millions of death every year. The repeated use of synthetic insecticides to control mosquitoes has created resistance to vectors and adverse environmental effects in addition to high operational cost. Many natural products have been reported as insect antifeedants or repellents. Azadirachta indica contains several active ingredients that are toxic to inse...

2011-01-01

174

Higher Mosquito Production in Low-Income Neighborhoods of Baltimore and Washington, DC: Understanding Ecological Drivers and Mosquito-Borne Disease Risk in Temperate Cities  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mosquito-vectored pathogens are responsible for devastating human diseases and are (re)emerging in many urban environments. Effective mosquito control in urban landscapes relies on improved understanding of the complex interactions between the ecological and social factors that define where mosquito populations can grow. We compared the density of mosquito habitat and pupae production across economically varying neighborhoods in two temperate U.S. cities (Baltimore, MD and Washington, DC). Se...

Ladeau, Shannon L.; Leisnham, Paul T.; Dawn Biehler; Danielle Bodner

2013-01-01

175

Larvicidal activity of neem oil (Azadirachta indica) formulation against mosquitoes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Azadirachta indica (Meliaceae) and its derived products have shown a variety of insecticidal properties. The pre...

2009-01-01

176

DsRed2 transient expression in Culex quinquefasciatus mosquitoes  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Culex quinquefasciatus mosquitoes have been successfully genetically modified only once, despite the efforts of several laboratories to transform and establish a stable strain. We have developed a transient gene expression method, in Culex, that delivers plasmid DNA directly to the mosquito haemoly [...] mph and additional tissues. We were able to express DsRed2 fluorescent protein in adult Cx. quinquefasciatus mosquitoes by injecting plasmids directly into their thorax. The expression of DsRed2 in adult Cx. quinquefasciatus mosquitoes is an important stepping stone to genetic transformation and the potential use of new control strategies and genetic interactions.

Wilke, Andre Barretto Bruno; Scaife, Sarah; Alphey, Luke; Marrelli, Mauro Toledo.

2013-06-01

177

Field evaluation of New Mountain Sandalwood Mosquito Sticks and New Mountain Sandalwood Botanical Repellent against mosquitoes in North Queensland, Australia.  

Science.gov (United States)

The mosquito repellent efficacy of New Mountain Sandalwood Mosquito Sticks (containing 0.5% w/w essential oils) and New Mountain Sandalwood Botanical Repellent (containing soybean and geranium oils) was assessed. Tests were conducted in the field with 4 volunteers in a wooded area near Cairns, North Queensland, Australia. Predominant biting species were Verrallina funerea and Ve. lineata. A pair of burning Mosquito Sticks immediately upwind of the subject (acting as an area repellent) provided a 73.1% mean reduction in mosquito landing and probing over the 3-h test period. The Botanical Repellent and a DEET-based control were both 100% effective in preventing mosquito probing for 3 h. These data are consistent with other studies of area repellents in that such products provide significant protection from mosquito bites, albeit inferior to the protection provided by topically applied repellents. PMID:16646344

Ritchie, Scott A; Williams, Craig R; Montgomery, Brian L

2006-03-01

178

[Mosquitoes as vectors for exotic pathogens in Germany].  

Science.gov (United States)

As a result of intensified globalization of international trade and of substantial travel activities, mosquito-borne exotic pathogens are becoming an increasing threat for Europe. In Germany some 50 different mosquito species are known, several of which have vector competence for pathogens. During the last few years a number of zoonotic arboviruses that are pathogenic for humans have been isolated from mosquitoes in Germany including Usutu, Sindbis and Batai viruses. In addition, filarial worms, such as Dirofilaria repens have been repeatedly detected in mosquitoes from the federal state of Brandenburg. Other pathogens, in particular West Nile virus, are expected to emerge sooner or later in Germany as the virus is already circulating in neighboring countries, e.g. France, Austria and the Czech Republic. In upcoming years the risk for arbovirus transmission might increase in Germany due to increased occurrence of new so-called "invasive" mosquito species, such as the Asian bush mosquito Ochlerotatus japonicus or the Asian tiger mosquito Aedes albopictus. These invasive species are characterized by high vector competence for a broad range of pathogens and a preference for human blood meals. For risk assessment, a number of mosquito and pathogen surveillance projects have been initiated in Germany during the last few years; however, mosquito control strategies and plans of action have to be developed and put into place to allow early and efficient action against possible vector-borne epidemics. PMID:24781910

Becker, N; Krüger, A; Kuhn, C; Plenge-Bönig, A; Thomas, S M; Schmidt-Chanasit, J; Tannich, E

2014-05-01

179

Play the Mosquito Game  

Science.gov (United States)

... and Insulin DNA - RNA - Protein DNA - the Double Helix Ear Pages ECG/Electrocardiogram Immune Responses Immune System ... parasite that is transmitted to humans by a female mosquito's bite. Read More » The Nobel Prize The ...

180

Modulation of La Crosse Virus Infection in Aedes albopictus Mosquitoes Following Larval Exposure to Coffee Extracts  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The mosquito-borne La Crosse virus (LACV; Family Bunyaviridae) may cause encephalitis, primarily in children, and is distributed throughout much of the eastern United States. No antivirals or vaccines are available for LACV, or most other mosquito-borne viruses, and prevention generally relies on mosquito control. We sought to determine whether coffee extracts could interfere with LACV replication and vector mosquito development. Both regular and decaffeinated coffee demonstrated significant ...

Eastep, Nicole E.; Albert, Rachel E.; Anderson, Justin R.

2012-01-01

 
 
 
 
181

Natural Plant Sugar Sources of Anopheles Mosquitoes Strongly Impact Malaria Transmission Potential  

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An improved knowledge of mosquito life history could strengthen malaria vector control efforts that primarily focus on killing mosquitoes indoors using insecticide treated nets and indoor residual spraying. Natural sugar sources, usually floral nectars of plants, are a primary energy resource for adult mosquitoes but their role in regulating the dynamics of mosquito populations is unclear. To determine how the sugar availability impacts Anopheles sergentii populations, mark-release-recapture ...

2011-01-01

182

Predicting mosquito infection from Plasmodium falciparum gametocyte density and estimating the reservoir of infection  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Transmission reduction is a key component of global efforts to control and eliminate malaria; yet, it is unclear how the density of transmission stages (gametocytes) influences infection (proportion of mosquitoes infected). Human to mosquito transmission was assessed using 171 direct mosquito feeding assays conducted in Burkina Faso and Kenya. Plasmodium falciparum infects Anopheles gambiae efficiently at low densities (4% mosquitoes at 1/mu l blood), although substantially more (> 200/mu l) ...

2013-01-01

183

Integrated mosquito larval source management reduces larval numbers in two highland villages in western Kenya  

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Background: In western Kenya, malaria remains one of the major health problems and its control remains an important public health measure. Malaria control is by either use of drugs to treat patients infected with malaria parasites or by controlling the vectors. Vector control may target the free living adult or aquatic (larval) stages of mosquito. The most commonly applied control strategies target indoor resting mosquitoes. However, because mosquitoes spend a considerable time in water, targ...

Imbahale, S. S.; Githeko, A.; Mukabana, W. R.; Takken, W.

2012-01-01

184

Integrated mosquito larval source management reduces larval numbers in two highland villages in western Kenya  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background In western Kenya, malaria remains one of the major health problems and its control remains an important public health measure. Malaria control is by either use of drugs to treat patients infected with malaria parasites or by controlling the vectors. Vector control may target the free living adult or aquatic (larval) stages of mosquito. The most commonly applied control strategies target indoor resting mosquitoes. However, because mosquitoes spend a conside...

2012-01-01

185

A Simple Colorimetric Assay for Specific Detection of Glutathione-S Transferase Activity Associated with DDT Resistance in Mosquitoes  

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Aedes mosquitoes transmit many human viral pathogens including dengue, yellow fever and chikungunya. Most of these pathogens have no specific treatment or vaccine and hence their control is reliant on controlling the mosquito vectors, which usually involves the use of insecticides. In order to prevent the alarming prospect of mosquito control failure due to the rapid selection and spread of insecticide resistance in several mosquito populations worldwide, it is essential that effective resist...

Morou, Evangelia; Dowd, Andrew J.; Rajatileka, Shavanti; Steven, Andrew; Hemingway, Janet; Ranson, Hilary; Paine, Mark; Vontas, John

2010-01-01

186

Mosquito repellents in frog skin  

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The search for novel insect repellents has been driven by health concerns over established synthetic compounds such as diethyl-m-toluamide (DEET). Given the diversity of compounds known from frog skin and records of mosquito bite and ectoparasite infestation, the presence of mosquito repellents in frogs seemed plausible. We investigated frog skin secretions to confirm the existence of mosquito repellent properties. Litoria caerulea secretions were assessed for mosquito repellency by topical a...

Williams, C. R.; Smith, B. P. C.; Best, S. M.; Tyler, M. J.

2006-01-01

187

Interrupting malaria transmission by genetic manipulation of anopheline mosquitoes  

Directory of Open Access Journals (Sweden)

Full Text Available Malaria ranks among the deadliest infectious diseases that kills more than one million persons everyyear. The mosquito is an obligatory vector for malaria transmission. In the mosquito, Plasmodiumundergoes a complex series of developmental events that includes transformation into severaldistinct morphological forms and the crossing of two different epithelia—midgut and salivarygland. Circumstantial evidence suggests that crossing of the epithelia requires specific interactionsbetween Plasmodium and epithelial surface molecules. By use of a phage display library we haveidentified a small peptide-SM1—that binds to the surfaces of the mosquito midgut and salivaryglands. Transgenic Anopheles stephensi mosquitoes expressing a SM1 tetramer from a bloodinducibleand gut-specific promoter are substantially impaired in their ability to sustain parasitedevelopment and transmission. A second effector gene, phospholipase A2, also impairs parasitetransmission in transgenic mosquitoes. These findings have important implications for the developmentof new strategies for malaria control.

Marcelo Jacobs-Lorena

2003-09-01

188

Taxis assays measure directional movement of mosquitoes to olfactory cues  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Malaria control methods targeting indoor-biting mosquitoes have limited impact on vectors that feed and rest outdoors. Exploiting mosquito olfactory behaviour to reduce blood-feeding outdoors might be a sustainable approach to complement existing control strategies. Methodologies that can objectively quantify responses to odour under realistic field conditions and allow high-throughput screening of many compounds are required for development of effective odour-based control strategies. The ol...

Lorenz, Lena M.; Keane, Aidan; Moore, Jason D.; Munk, Cristina J.; Seeholzer, Laura; Mseka, Antony; Simfukwe, Emmanuel; Ligamba, Joseph; Turner, Elizabeth L.; Biswaro, Lubandwa R.; Okumu, Fredros O.; Killeen, Gerry F.; Mukabana, Wolfgang R.; Moore, Sarah J.

2013-01-01

189

The Knowledge and Experience of Dengue Mosquitoes among Housewives.  

Directory of Open Access Journals (Sweden)

Full Text Available Dengue Hemorrhagic Fever (DHF prevention programs in Semarang, were focused through controlling mosquito breeding sites (PSN, but the implementation of PSN was not become a habit in every household. The objective of this study was to explore knowledge and experience of dengue mosquitoes among housewives in the endemic villages.The research was using qualitative methods. Subjects of the study were 17 housewives which selected by purposive sampling. The data collection was carried in Sendangmulyo village, Semarang, through observation, focus groups discussions, and indepth interviews. The techniques used to test data validity were triangulation and member checking method. Data were analyzed using content analysis approached. The results showed that housewives classifying mosquito based on time occurrence whether the presence of mosquito in environment was perceived naturally. Unoptimalized PSN behavior was based on the lack of housewives knowledge on larvae development stages. Mosquito was not considered as a threatening because night mosquito biting was directly more disturbing rather than day mosquitoes’. Health promotion program could increase dasa wisma cadres knowledge and skill, particularly on mosquito life cycle and the correct stages of PSN behavior. This study did not distinguish the demographic characteristics of informants. Further reserch could explore it or develop media based on local knowledge and experience.

Atik Triratnawati

2011-06-01

190

Study of mosquito attractants for photo catalytic mosquito trap  

Directory of Open Access Journals (Sweden)

Full Text Available Photo catalytic mosquito trap is made of TiO2-Activated Carbon (AC with a certain composition of AC. Research concerns on the heat spectrum which is produced by combination process of existing CO2 and humid air. The purpose of performance testing is to observe capability of this device in trapping mosquitoes related to the air temperature profile for heat spectrum is play important role for attracting mosquitoes. Result shows photo catalytic mosquito trap is more effective than devices which only consist of UV light or stream of CO2 and the humid air. A number of mosquitoes trapped by the photo catalyst coated panel configuration and UV lamps were lit proved far more effective because the heat production from recombination process. A little difference in temperature can be detected by mosquito.   Keywords: Photo Catalytic, Mosquito, Recombination.

Dewi Tristantini

2014-01-01

191

Radiation biology of mosquitoes  

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Full Text Available Abstract There is currently renewed interest in assessing the feasibility of the sterile insect technique (SIT to control African malaria vectors in designated areas. The SIT relies on the sterilization of males before mass release, with sterilization currently being achieved through the use of ionizing radiation. This paper reviews previous work on radiation sterilization of Anopheles mosquitoes. In general, the pupal stage was irradiated due to ease of handling compared to the adult stage. The dose-response curve between the induced sterility and log (dose was shown to be sigmoid, and there was a marked species difference in radiation sensitivity. Mating competitiveness studies have generally been performed under laboratory conditions. The competitiveness of males irradiated at high doses was relatively poor, but with increasing ratios of sterile males, egg hatch could be lowered effectively. Males irradiated as pupae had a lower competitiveness compared to males irradiated as adults, but the use of partially-sterilizing doses has not been studied extensively. Methods to reduce somatic damage during the irradiation process as well as the use of other agents or techniques to induce sterility are discussed. It is concluded that the optimal radiation dose chosen for insects that are to be released during an SIT programme should ensure a balance between induced sterility of males and their field competitiveness, with competitiveness being determined under (semi- field conditions. Self-contained 60Co research irradiators remain the most practical irradiators but these are likely to be replaced in the future by a new generation of high output X ray irradiators.

Knols Bart GJ

2009-11-01

192

MosquitoMap and the Mal-area calculator: new web tools to relate mosquito species distribution with vector borne disease  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Mosquitoes are important vectors of diseases but, in spite of various mosquito faunistic surveys globally, there is a need for a spatial online database of mosquito collection data and distribution summaries. Such a resource could provide entomologists with the results of previous mosquito surveys, and vector disease control workers, preventative medicine practitioners, and health planners with information relating mosquito distribution to vector-borne disease risk. Results A web application called MosquitoMap was constructed comprising mosquito collection point data stored in an ArcGIS 9.3 Server/SQL geodatabase that includes administrative area and vector species x country lookup tables. In addition to the layer containing mosquito collection points, other map layers were made available including environmental, and vector and pathogen/disease distribution layers. An application within MosquitoMap called the Mal-area calculator (MAC was constructed to quantify the area of overlap, for any area of interest, of vector, human, and disease distribution models. Data standards for mosquito records were developed for MosquitoMap. Conclusion MosquitoMap is a public domain web resource that maps and compares georeferenced mosquito collection points to other spatial information, in a geographical information system setting. The MAC quantifies the Mal-area, i.e. the area where it is theoretically possible for vector-borne disease transmission to occur, thus providing a useful decision tool where other disease information is limited. The Mal-area approach emphasizes the independent but cumulative contribution to disease risk of the vector species predicted present. MosquitoMap adds value to, and makes accessible, the results of past collecting efforts, as well as providing a template for other arthropod spatial databases.

Christensen Jamie

2010-02-01

193

UV light and urban pollution: Bad cocktail for mosquitoes?  

Energy Technology Data Exchange (ETDEWEB)

Highlights: •Mosquito tolerance to temephos is induced by PAHs and UV exposure. •Toxicity of fluoranthene for mosquito Malpighian tubules cells is induced by UV. •Fluoranthene crystallizes in mosquito Malpighian tubules upon UV exposure. •Mixture of two PAHs is less toxic for mosquitoes than each PAHs separately. •Combination of abiotic parameters (PAHs and UV) affect mosquito physiology. -- Abstract: Mosquito breeding sites consist of water pools, which can either be large open areas or highly covered ponds with vegetation, thus with different light exposures combined with the presence in water of xenobiotics including polycyclic aromatic hydrocarbons (PAHs) generated by urban pollution. UV light and PAHs are abiotic factors known to both affect the mosquito insecticide resistance status. Nonetheless, their potential combined effects on the mosquito physiology have never been investigated. The present article aims at describing the effects of UV exposure alongside water contamination with two major PAH pollutants (fluoranthene and benzo[a]pyrene) on a laboratory population of the yellow fever mosquito Aedes aegypti. To evaluate the effects of PAH exposure and low energetic UV (UV-A) irradiation on mosquitoes, different parameters were measured including: (1) The PAH localization and its impact on cell mortality by fluorescent microscopy; (2) The detoxification capacities (cytochrome P450, glutathione-S-transferase, esterase); (3) The responses to oxidative stress (Reactive Oxygen Species–ROS) and (4) The tolerance of mosquito larvae to a bioinsecticide (Bacillus thuringiensis subsp. israelensis–Bti) and to five chemical insecticides (DDT, imidacloprid, permethrin, propoxur and temephos). Contrasting effects regarding mosquito cell mortality, detoxification and oxidative stress were observed as being dependent on the pollutant considered, despite the fact that the two PAHs belong to the same family. Moreover, UV is able to modify pollutant effects on mosquitoes, including tolerance to three insecticides (imidacloprid, propoxur and temephos), cell damage and response to oxidative stress. Taken together, our results suggest that UV and pollution, individually or in combination, are abiotic parameters that can affect the physiology and insecticide tolerance of mosquitoes; but the complexity of their direct effect and of their interaction will require further investigation to know in which condition they can affect the efficacy of insecticide-based vector control strategies in the field.

Tetreau, Guillaume, E-mail: guillaume.tetreau@gmail.com [Laboratoire d’Ecologie Alpine, LECA-UMR 5553, Université de Grenoble 1, BP 53, 38041 Grenoble cedex 09 (France); Department of Entomology, Cornell University, New York State Agricultural Experiment Station, Geneva, NY 14456 (United States); Chandor-Proust, Alexia; Faucon, Frédéric; Stalinski, Renaud; Akhouayri, Idir; Prud’homme, Sophie M.; Régent-Kloeckner, Myriam; Raveton, Muriel; Reynaud, Stéphane [Laboratoire d’Ecologie Alpine, LECA-UMR 5553, Université de Grenoble 1, BP 53, 38041 Grenoble cedex 09 (France)

2014-01-15

194

UV light and urban pollution: Bad cocktail for mosquitoes?  

International Nuclear Information System (INIS)

Highlights: •Mosquito tolerance to temephos is induced by PAHs and UV exposure. •Toxicity of fluoranthene for mosquito Malpighian tubules cells is induced by UV. •Fluoranthene crystallizes in mosquito Malpighian tubules upon UV exposure. •Mixture of two PAHs is less toxic for mosquitoes than each PAHs separately. •Combination of abiotic parameters (PAHs and UV) affect mosquito physiology. -- Abstract: Mosquito breeding sites consist of water pools, which can either be large open areas or highly covered ponds with vegetation, thus with different light exposures combined with the presence in water of xenobiotics including polycyclic aromatic hydrocarbons (PAHs) generated by urban pollution. UV light and PAHs are abiotic factors known to both affect the mosquito insecticide resistance status. Nonetheless, their potential combined effects on the mosquito physiology have never been investigated. The present article aims at describing the effects of UV exposure alongside water contamination with two major PAH pollutants (fluoranthene and benzo[a]pyrene) on a laboratory population of the yellow fever mosquito Aedes aegypti. To evaluate the effects of PAH exposure and low energetic UV (UV-A) irradiation on mosquitoes, different parameters were measured including: (1) The PAH localization and its impact on cell mortality by fluorescent microscopy; (2) The detoxification capacities (cytochrome P450, glutathione-S-transferase, esterase); (3) The responses to oxidative stress (Reactive Oxygen Species–ROS) and (4) The tolerance of mosquito larvae to a bioinsecticide (Bacillus thuringiensis subsp. israelensis–Bti) and to five chemical insecticides (DDT, imidacloprid, permethrin, propoxur and temephos). Contrasting effects regarding mosquito cell mortality, detoxification and oxidative stress were observed as being dependent on the pollutant considered, despite the fact that the two PAHs belong to the same family. Moreover, UV is able to modify pollutant effects on mosquitoes, including tolerance to three insecticides (imidacloprid, propoxur and temephos), cell damage and response to oxidative stress. Taken together, our results suggest that UV and pollution, individually or in combination, are abiotic parameters that can affect the physiology and insecticide tolerance of mosquitoes; but the complexity of their direct effect and of their interaction will require further investigation to know in which condition they can affect the efficacy of insecticide-based vector control strategies in the field

2014-01-01

195

Mosquito larvicidal activity of botanical-based mosquito repellents.  

Science.gov (United States)

The larvicidal activity of 4 plant essential oils--innamon oil, lemon eucalyptus oil, sandalwood oil, and turmeric oil--previously reported as insect repellents was evaluated in the laboratory against 4th instars of Aedes albopictus, Ae. aegypti, and Culex pipiens. Sandalwood oil appeared to be the most effective of the larvicides, killing larvae of all 3 mosquito species in relatively short times. The values of LT50 and LT90 at the application dosage (0.2 mg/ml) were 1.06 +/- 0.11 and 3.24 +/- 0.14 h for Ae. aegypti, 1.82 +/- 0.06 and 3.33 +/- 0.48 h for Ae. albopictus, and 1.55 +/- 0.07 and 3.91 +/- 0.44 h for Cx. pipiens, respectively. Chemical compositions of these essential oils were also studied, and the lavicidal activity of their major ingredient compounds was compared with that of each of the essential oils. The acute toxicity of the 4 essential oils to fathead minnows was also evaluated. The safe use of these natural plant essential oils in future applications of mosquito control was discussed. PMID:18437833

Zhu, Junwei; Zeng, Xiaopeng; O'Neal, Megan; Schultz, Gretchen; Tucker, Brad; Coats, Joel; Bartholomay, Lyric; Xue, Rui-De

2008-03-01

196

Pesticides and public health: integrated methods of mosquito management.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pesticides have a role in public health as part of sustainable integrated mosquito management. Other components of such management include surveillance, source reduction or prevention, biological control, repellents, traps, and pesticide-resistance management. We assess the future use of mosquito control pesticides in view of niche markets, incentives for new product development, Environmental Protection Agency registration, the Food Quality Protection Act, and improved pest management strate...

Rose, R. I.

2001-01-01

197

Identification of mosquito repellent odours from Ocimum forskolei  

Science.gov (United States)

Background Native mosquito repellent plants have a good potential for integrated mosquito control in local settings. Ocimum forskolei, Lamiaceae, is used in Eritrea as a spatial mosquito repellent inside houses, either through crushing fresh plants or burning dry plants. We verified whether active repellent compounds could be identified using gas-chromatography coupled electroantennogram recordings (GC-EAD) with headspace extracts of crushed plants. Results EAD active compounds included (R)-(-)-linalool, (S)-(+)-1-octen-3-ol, trans-caryophyllene, naphthalene, methyl salicylate, (R)-(-)-?-copaene, methyl cinnamate and (E)-ocimene. Of these compounds (R)-(-)-linalool, methyl cinnamate and methyl salicylate reduced landing of female Aedes aegypti on human skin-odor baited tubes. The latter two are novel mosquito repellent compounds. Conclusions The identification of mosquito repellent compounds contributes to deciphering the mechanisms underlying repulsion, supporting the rational design of novel repellents. The three mosquito repellent compounds identified in this study are structurally dissimilar, which may indicate involvement of different sensory neurons in repulsion. Repulsion may well be enhanced through combining different repellent plants (or their synthetic mimics), and can be a locally sustainable part in mosquito control efforts.

2011-01-01

198

Identification of mosquito repellent odours from Ocimum forskolei  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Native mosquito repellent plants have a good potential for integrated mosquito control in local settings. Ocimum forskolei, Lamiaceae, is used in Eritrea as a spatial mosquito repellent inside houses, either through crushing fresh plants or burning dry plants. We verified whether active repellent compounds could be identified using gas-chromatography coupled electroantennogram recordings (GC-EAD with headspace extracts of crushed plants. Results EAD active compounds included (R-(--linalool, (S-(+-1-octen-3-ol, trans-caryophyllene, naphthalene, methyl salicylate, (R-(--?-copaene, methyl cinnamate and (E-ocimene. Of these compounds (R-(--linalool, methyl cinnamate and methyl salicylate reduced landing of female Aedes aegypti on human skin-odor baited tubes. The latter two are novel mosquito repellent compounds. Conclusions The identification of mosquito repellent compounds contributes to deciphering the mechanisms underlying repulsion, supporting the rational design of novel repellents. The three mosquito repellent compounds identified in this study are structurally dissimilar, which may indicate involvement of different sensory neurons in repulsion. Repulsion may well be enhanced through combining different repellent plants (or their synthetic mimics, and can be a locally sustainable part in mosquito control efforts.

Glinwood Robert

2011-09-01

199

Evaluation of a Stable Isotope Method to Mark Naturally-Breeding Larval Mosquitoes for Adult Dispersal Studies  

Science.gov (United States)

Understanding mosquito dispersal is critically important for vector-borne disease control and prevention. Mark–release–recapture methods using various marking techniques have made substantial contributions to the study of mosquito biology. However, the ability to mark naturally breeding mosquitoes noninvasively and with life-long retention has remained problematic. Here, we describe a method to mark naturally breeding mosquitoes with stable isotopes. Culexpipiens f. molestus mosquitoes were provisioned as larvae in laboratory experiments with 15N-labeled potassium nitrate and 13C-labeled glucose. Larval enrichment was sufficient to differentiate marked adult mosquitoes from unmarked control mosquitoes and the natural source population from Chicago Illinois, using either ?15N or ?13C. Isotopic retention lasted for at least 55 d for adult male and females mosquitoes. There were no consistent effects of isotopic enrichment on immature mosquito survival or adult mosquito body size. We then applied this marking technique to naturally breeding Culex pipiens mosquitoes in suburban Chicago, IL, and for the first time, report successful isotopic enrichment of mosquitoes in the field. This stable isotope marking technique will facilitate studies of mosquito dispersal.

HAMER, GABRIEL L.; DONOVAN, DANIELLE J.; HOOD-NOWOTNY, REBECCA; KAUFMAN, MICHAEL G.; GOLDBERG, TONY L.; WALKER, EDWARD D.

2014-01-01

200

Biocontrol of larval mosquitoes by Acilius sulcatus (Coleoptera: Dytiscidae  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Problems associated with resistant mosquitoes and the effects on non-target species by chemicals, evoke a reason to find alternative methods to control mosquitoes, like the use of natural predators. In this regard, aquatic coleopterans have been explored less compared to other insect predators. In the present study, an evaluation of the role of the larvae of Acilius sulcatus Linnaeus 1758 (Coleoptera: Dytiscidae as predator of mosquito immatures was made in the laboratory. Its efficacy under field condition was also determined to emphasize its potential as bio-control agent of mosquitoes. Methods In the laboratory, the predation potential of the larvae of A. sulcatus was assessed using the larvae of Culex quinquefasciatus Say 1823 (Diptera: Culicidae as prey at varying predator and prey densities and available space. Under field conditions, the effectiveness of the larvae of A. sulcatus was evaluated through augmentative release in ten cemented tanks hosting immatures of different mosquito species at varying density. The dip density changes in the mosquito immatures were used as indicator for the effectiveness of A. sulcatus larvae. Results A single larva of A. sulcatus consumed on an average 34 IV instar larvae of Cx. quinquefasciatus in a 24 h period. It was observed that feeding rate of A. sulcatus did not differ between the light-on (6 a.m. – 6 p.m., and dark (6 p.m. – 6 a.m. phases, but decreased with the volume of water i.e., space availability. The prey consumption of the larvae of A. sulcatus differed significantly (P A. sulcatus larvae, while with the withdrawal, a significant increase (p A. sulcatus in regulating mosquito immatures. In the control tanks, mean larval density did not differ (p > 0.05 throughout the study period. Conclusion the larvae of the dytiscid beetle A. sulcatus proved to be an efficient predator of mosquito immatures and may be useful in biocontrol of medically important mosquitoes.

Banerjee Siddhartha S

2008-10-01

 
 
 
 
201

Potential Use of Mosquito’s Salivary Components as Novel Target for The Development of Transmission Blocking Vaccine (TBV  

Directory of Open Access Journals (Sweden)

Full Text Available Mosquito-borne diseases are rampant in most tropical regions of the world, especially rural, forested, and coastal areas such as Indonesia. Despite long-standing chemotherapeutic intercession and vector control programs, mosquito-borne diseases exact a heavy burden on human health in Indonesia. Two major public health problems transmitted by mosquito in Indonesia are malaria and dengue haemorrhagic fever (DHF, causing millions of clinical episodes occurring annually. Malaria is now recognized as a serious re-emerging threat to public health. DHF cases were first observed in 1968; since then, the incidence has been constantly increasing and the disease is now one of the principal causes of child lethality. It has been widely observed that saliva of mosquito that transmits the diseases contains several factors that could enhance pathogen infection. Therefore, it should be possible to control pathogen transmission by vaccinating the host against the molecule(s in saliva that potentiate the infection. However, specific component as a potential target for TBV in mosquito vectors of malaria & dengue, i.e. Anopheles and Aedes aegypti, has not been identified so far. This paper wanted to elaborate the potential role of salivary component from mosquitoes, particularly from Indonesian vectors as molecular target for developing TBV against two major Mosquito borne-diseases in Indonesia i.e. malaria and DHF.

KARTIKA SENJARINI

2013-11-01

202

Mosquito communities with trap height and urban-rural gradient in Adelaide, South Australia: implications for disease vector surveillance.  

Science.gov (United States)

Understanding the factors influencing mosquito distribution is important for effective surveillance and control of nuisance and disease vector mosquitoes. The goal of this study was to determine how trap height and distance to the city center influenced the abundance and species of mosquitoes collected in Adelaide, South Australia. Mosquito communities were sampled at two heights (practice of setting traps within two meters of the ground is effective for sampling populations of the important disease vector species in South Australia. PMID:24820555

Johnston, Emily; Weinstein, Phillip; Slaney, David; Flies, Andrew S; Fricker, Stephen; Williams, Craig

2014-06-01

203

A synthetic homing endonuclease-based gene drive system in the human malaria mosquito  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Genetic methods of manipulating or eradicating disease vector populations have long been discussed as an attractive alternative to existing control measures because of their potential advantages in terms of effectiveness and species specificity1–3. The development of genetically engineered malaria-resistant mosquitoes has shown, as a proof-of-principle, the possibility of targeting the mosquito’s ability to serve as a disease vector4–7. The translation of these achievements into control...

Windbichler, Nikolai; Menichelli, Miriam; Papathanos, Philippos Aris; Thyme, Summer B.; Li, Hui; Ulge, Umut Y.; Hovde, Blake T.; Baker, David; Monnat, Raymond J.; Burt, Austin; Crisanti, Andrea

2011-01-01

204

Potential of biologically active plant oils to control mosquito larvae (Culex pipiens, Diptera: Culicidae from an egyptian locality Potencial de óleos de plantas biologicamente ativos para o controle da larva do mosquito Culex pipiens (Diptera: Culicidae de localidade egípcia  

Directory of Open Access Journals (Sweden)

Full Text Available The insecticidal effect of six commercially available plant oils was tested against 4th larval instars of Culex pipiens. Larvae were originally collected from Meit El-Attar, Qalyubia Governorate, Egypt, and then reared in the laboratory until F1 generation. The LC50 values were 32.42, 47.17, 71.37, 83.36, 86.06, and 152.94 ppm for fenugreek (Trigonella foenum-grecum, earth almond (Cyperus esculentus, mustard (Brassica compestris, olibanum (Boswellia serrata, rocket (Eruca sativa, and parsley (Carum ptroselinum, respectively. The tested oils altered some biological aspects of C. pipiens, for instance, developmental periods, pupation rates, and adult emergences. The lowest concentrations of olibanum and fenugreek oils caused remarkable prolongation of larval and pupal durations. Data also showed that the increase of concentrations was directly proportional to reduction in pupation rates and adult emergences. Remarkable decrease in pupation rate was achieved by mustard oil at 1000 ppm. Adult emergence was suppressed by earth almond and fenugreek oils at 25 ppm. In addition, the tested plant oils exhibited various morphological abnormalities on larvae, pupae, and adult stages. Consequently, fenugreek was the most potent oil and the major cause of malformation of both larval and pupal stages. Potency of the applied plant oils provided an excellent potential for controlling C. pipiens.O efeito inseticida de seis óleos de plantas comercialmente disponíveis foi testado contra larvas de 4ºinstar de Culex pipiens. Larvas foram coletadas originalmente de Meit El-Attar, Qalyubia Governorate, Egito e então cultivadas no laboratório até a geração F1. Os valores LC50 foram 32,42, 47,17, 71,37, 83,36, 86,06 e 152,94 ppm para o feno grego (Trigonella foenum-grecum, amêndoa da terra (Cyperus esculentus, mostarda (Brassica compestris, olíbano (Boswellia serrata, rocket (Eruca sativa e salsa (Carum ptroselium, respectivamente. Os óleos testados alteraram alguns aspectos biológicos do C. pipiens, por exemplo os períodos de desenvolvimento, estados de crisálida, e emergências de adultos. As concentrações mais baixas de óleo de olíbano e feno grego causaram extraordinário prolongamento da duração larval e pupal. Dados também mostraram que o aumento das concentrações foi diretamente proporcional à redução no estado de crisálida e emergências dos adultos. Notável decréscimo no estado de crisálida foi conseguido com o óleo de mostarda a 1000 ppm. Emergência de adulto foi diminuída no óleo de amêndoa da terra e feno grego a 25 ppm. Além do mais, os óleos de plantas testados, exibiram várias anormalidades morfológicas nas larvas, pupas e estádios adultos. Consequentemente, o óleo de feno grego foi o óleo mais potente e o maior causador de malformação em ambos estádios larval e pupal. Potencial dos óleos de plantas aplicados mostraram excelente resultado no controle do C. pipiens.

Hanem Fathy Khater

2008-04-01

205

MICROBIOLOGY: Mosquitoes Cut Short  

Science.gov (United States)

Access to the article is free, however registration and sign-in are required. Forty years ago, as the first drug- and insecticide-based global malaria eradication plan was being abandoned, the concept was raised of using evolutionary genetics to fight vector-borne diseases like malaria, dengue, and river blindness (1).The idea was to exploit selfish genetic elements, entities that can spread through host populations by distorting normal Mendelian inheritance, thereby enhancing their own transmission. In a Perspective by Read and Thomas, they discuss how McMeniman et al. (2) report a major step in a lateral development of this approach. They have infected the mosquito species that transmit dengue viruses to humans with an inheritance-distorting bacterium that kills mosquitoes likely to be infectious.

Andrew F. Read (Pennsylvania State University;Center for Infectious Disease Dynamics, Department of Biology); Matthew B. Thomas (Pennsylvania State University;Center for Infectious Disease Dynamics, Department of Entomology, Pennsylvania State University, University Park, PA 16802, USA.)

2009-01-02

206

Avaliação de estirpes e de uma nova formulação granulada de Bacillus sphaericus Neide para o controle de mosquitos / Evaluation of isolates and a new granular formulation of Bacillus sphaericus Neide for control of mosquitoes  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Foram estudadas 19 estirpes de Bacillus sphaericus Neide obtidos no Brasil além de uma estirpe considerada padrão (2362) fornecida pelo Instituto Pasteur. A maioria das estirpes foi mais eficiente que o padrão, sendo que sete deles causaram mortalidade igual ou superior a 80%, em baixa concentração [...] (7 × 10² esporos/ml). A estirpe ESALQ MS6 foi selecionada para formulação por apresentar melhor produção, em meio de cultura líquido (3 × 10(9) UFC/ml). A formulação granulada G4 foi testada em criadouros artificiais, constituídos de baldes plásticos com 10 L de água e 20 larvas de 3º ínstar de Culex quinquefasciatus Say (Diptera: Culicidae). Comparou-se a eficiência da formulação em teste, em três concentrações diferentes, com um produto comercial. As avaliações foram feitas 24 horas, sete e 18 dias após a inoculação, seguindo-se a reposição de larvas no balde. A formulação G4 foi semelhante ao produto comercial, controlando 100% das larvas nas concentrações testadas, contudo teve maior tempo de permanência dos grânulos na superfície. Em lagoas de tratamento de efluentes de cortume, a formulação G4, na concentração de 2 kg/ha reduziu o número de larvas em 21%, 47%, 85% e 94%, após 1, 3, 7 e 15 dias, respectivamente. Abstract in english Nineteen Bacillus sphaericus Neide strains obtained in Brazil were evaluated in addition to a standard strain (2362) supplied by Pasteur Institute. Most strains were more efficient than the standard, and seven of them caused mortality equal to or higher than 80%, at a low concentration (7 × 10 [...] ² spores/ml). Strain ESALQ MS6 was selected for formulation, since it showed better yield in liquid culture medium (3 × 10(9) CFU/ml). The G4 granular formulation was tested in artificial rearing sites, consisting of plastic buckets containing 10 L water and twenty 3rd-instar larvae of Culex quinquefasciatus Say (Diptera: Culicidae). The efficiency of formulation was compared against a commercial product, at three different concentrations. Evaluations were taken every 24h, at seven and 18 days after inoculation, with subsequent replacement of larvae in the bucket. The G4 formulation was similar to the commercial product, and controlled 100% of the larvae at the concentrations tested; however, the granules remained at the surface for a longer period. In tannery effluent treatment ponds, the G4 formulation at a concentration of 2 kg/ha reduced the number of larvae by 21%, 47%, 85%, and 94%, after 1, 3, 7, and 15 days, respectively.

Alves, Luis F.A.; Alves, Sérgio B.; Lopes, José; Lopes, Rogério B..

207

Mosquitoes of western Uganda.  

Science.gov (United States)

The mosquito fauna in many areas of western Uganda has never been studied and is currently unknown. One area, Bwamba County, has been previously studied and documented but the species lists have not been updated for >40 yr. This paucity of data makes it difficult to determine which arthropod-borne viruses pose a risk to human or animal populations. Using CO2 baited-light traps, from 2008 through 2010, 67,731 mosquitoes were captured at five locations in western Uganda including Mweya, Sempaya, Maramagambo, Bwindi (BINP), and Kibale (KNP). Overall, 88 mosquito species, 7 subspecies, and 7 species groups in 10 genera were collected. The largest number of species was collected at Sempaya (65 species), followed by Maramagambo (45), Mweya (34), BINP (33), and KNP (22). However, species diversity was highest in BINP (Simpson's Diversity Index 1-D = 0.85), followed by KNP (0.80), Maramagambo (0.79), Sempaya (0.67), and Mweya (0.56). Only six species Aedes (Aedimorphus) cumminsii (Theobald), Aedes (Neomelaniconion) circumluteolus (Theobald), Culex (Culex) antennatus (Becker), Culex (Culex) decens group, Culex (Lutzia) tigripes De Grandpre and De Charmoy, and Culex (Oculeomyia) annulioris (Theobald), were collected from all five sites suggesting large differences in species composition among sites. Four species (Aedes (Stegomyia) metallicus (Edwards), Anopheles (Cellia) rivulorum Leeson, Uranotaenia (Uranotaenia) chorleyi (Edwards), and Uranotaenia (Uranotaenia) pallidocephala (Theobald) and one subspecies (Aedes (Stegomyia) aegypti formosus (Walker)) were collected in Bwamba County for the first time. This study represents the first description of the mosquito species composition of Mweya, Maramagambo, BINP, and KNP. A number of morphological variations were noted regarding the postspiracular scales, hind tibia, and sternites that make Culex (Culex) neavei (Theobald) challenging to identify. At least 50 species collected in this study have previously been implicated in the transmission of arboviruses of public health importance suggesting a high potential for maintenance and transmission of a wide variety of arboviruses in western Uganda. PMID:23270157

Mutebi, J-P; Crabtree, M B; Kading, R C; Powers, A M; Lutwama, J J; Miller, B R

2012-11-01

208

Toxicity of a plant based mosquito repellent/killer  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The mission to make humans less attractive to mosquitoes has fuelled decades of scientific research on mosquito behaviour and control. The search for the perfect topical insect repellent/killer continues. This analysis was conducted to review and explore the scientific information on toxicity produced by the ingredients/contents of a herbal product. In this process of systemic review the following methodology was applied. By doing a MEDLINE search with key words of selected plants, plant base...

Singh, Bhoopendra; Singh, Prakash Raj; Mohanty, Manoj Kumar

2012-01-01

209

BIOACTIVIDAD DE ACEITES ESENCIALES DE Minthostachys mollis CONTRA MOSQUITOS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

El control químico de vectores es una herramienta principal de prevención de enfermedades transmitidas por mosquitos. Los aceites esenciales (AE) de plantas pueden ser una alternativa a los compuestos sintéticos. Se extrajeron por arrastre con vapor AE de Minthostachys mollis y se evaluó su actividad insecticida contra larvas, pupas y adultos de mosquitos, según protocolos estándar de la Organización Mundial de la Salud. Se evaluaron concentraciones entre 10 y 160 ppm del AE y se regis...

2007-01-01

210

UV light and urban pollution: bad cocktail for mosquitoes?  

Science.gov (United States)

Mosquito breeding sites consist of water pools, which can either be large open areas or highly covered ponds with vegetation, thus with different light exposures combined with the presence in water of xenobiotics including polycyclic aromatic hydrocarbons (PAHs) generated by urban pollution. UV light and PAHs are abiotic factors known to both affect the mosquito insecticide resistance status. Nonetheless, their potential combined effects on the mosquito physiology have never been investigated. The present article aims at describing the effects of UV exposure alongside water contamination with two major PAH pollutants (fluoranthene and benzo[a]pyrene) on a laboratory population of the yellow fever mosquito Aedes aegypti. To evaluate the effects of PAH exposure and low energetic UV (UV-A) irradiation on mosquitoes, different parameters were measured including: (1) The PAH localization and its impact on cell mortality by fluorescent microscopy; (2) The detoxification capacities (cytochrome P450, glutathione-S-transferase, esterase); (3) The responses to oxidative stress (Reactive Oxygen Species-ROS) and (4) The tolerance of mosquito larvae to a bioinsecticide (Bacillus thuringiensis subsp. israelensis-Bti) and to five chemical insecticides (DDT, imidacloprid, permethrin, propoxur and temephos). Contrasting effects regarding mosquito cell mortality, detoxification and oxidative stress were observed as being dependent on the pollutant considered, despite the fact that the two PAHs belong to the same family. Moreover, UV is able to modify pollutant effects on mosquitoes, including tolerance to three insecticides (imidacloprid, propoxur and temephos), cell damage and response to oxidative stress. Taken together, our results suggest that UV and pollution, individually or in combination, are abiotic parameters that can affect the physiology and insecticide tolerance of mosquitoes; but the complexity of their direct effect and of their interaction will require further investigation to know in which condition they can affect the efficacy of insecticide-based vector control strategies in the field. PMID:24275062

Tetreau, Guillaume; Chandor-Proust, Alexia; Faucon, Frédéric; Stalinski, Renaud; Akhouayri, Idir; Prud'homme, Sophie M; Régent-Kloeckner, Myriam; Raveton, Muriel; Reynaud, Stéphane

2014-01-01

211

Effects of a botanical larvicide derived from Azadirachta indica (the neem tree) on oviposition behaviour in Anopheles gambiae s.s. mosquitoes  

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More focus is given to mosquito larval control due to the necessity to use several control techniques together in integrated vector management programmes. Botanical products are thought to be able to provide effective, sustainable and cheap mosquito larval control tools. However, bio-larvicides like Azadirachta indica (neem) could repel adult mosquitoes from laying their eggs in the treated larval habitats. In this study the response of Anopheles gambiae s.s. mosquitoes towards varying doses ...

Howard, A. F. V.; Adongo, E. A.; Vulule, J.; Githure, J.

2011-01-01

212

Pesticide-Free Device a Fatal Attraction for Mosquitoes  

Science.gov (United States)

Are those pesky mosquitoes getting more entertainment out of your family picnic than you are? If the answer is yes, then it is time to reclaim your backyard with assistance from an unlikely partner. Nowadays, NASA is developing tools to track and predict the spread of the West Nile Virus on a global scale, but several years ago, the Space Agency carved out some time to collaborate with an outdoor products manufacturer in order to help control mosquito populations on a local level. The technology resulting from this union leveraged a space-age heat blanket to attract mosquitoes, which would then be eliminated without the use of harmful pesticides or chemicals. technical assistance from NASA and is an environmentally safe way to reduce the mosquito population.

2005-01-01

213

Effectiveness of an integrated vector management control strategy for the tiger mosquito (Aedes albopictus) a case study in Sant Cugat del Vallès (Barcelona) /  

Digital Repository Infrastructure Vision for European Research (DRIVER)

El mosquito tigre, Aedes albopictus (Skuse, 1894), es una especie invasora que actualmente se encuentra en los cinco continentes, extendiéndose desde su área nativa en el sudeste de Asia a través del comercio internacional de neumáticos usados y del bambú de la suerte. En Cataluña fue detectado por primera vez en el año 2004, en el municipio Sant Cugat del Vallès, y se expandió rápidamente en los últimos cinco años a más de 200 municipios de Cataluña y Alicante. Esta especie es ...

Abramides, Gisela Chebabi

2013-01-01

214

Genetic elimination of dengue vector mosquitoes  

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An approach based on mosquitoes carrying a conditional dominant lethal gene (release of insects carrying a dominant lethal, RIDL) is being developed to control the transmission of dengue viruses by vector population suppression. A transgenic strain, designated OX3604C, of the major dengue vector, Aedes aegypti, was engineered to have a repressible female-specific flightless phenotype. This strain circumvents the need for radiation-induced sterilization, allows genetic sexing resulting in male...

2011-01-01

215

Identification of mosquito repellent odours from Ocimum forskolei  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Native mosquito repellent plants have a good potential for integrated mosquito control in local settings. Ocimum forskolei, Lamiaceae, is used in Eritrea as a spatial mosquito repellent inside houses, either through crushing fresh plants or burning dry plants. We verified whether active repellent compounds could be identified using gas-chromatography coupled electroantennogram recordings (GC-EAD) with headspace extracts of crushed plants. R...

Dekker Teun; Ignell Rickard; Ghebru Maedot; Glinwood Robert; Hopkins Richard

2011-01-01

216

Insecticide-Treated Nets Can Reduce Malaria Transmission by Mosquitoes Which Feed Outdoors  

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Insecticide treated nets (ITNs) represent a powerful means for controlling malaria in Africa because the mosquito vectors feed primarily indoors at night. The proportion of human exposure that occurs indoors, when people are asleep and can conveniently use ITNs, is therefore very high. Recent evidence suggests behavioral changes by malaria mosquito populations to avoid contact with ITNs by feeding outdoors in the early evening. We adapt an established mathematical model of mosquito behavior a...

2010-01-01

217

Preliminary Analysis of Several Attractants and Spatial Repellents for the Mosquito, Aedes albopictus using an Olfactometer  

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Mosquito attractants and spatial repellents hold great promise in controlling mosquito pests. In assessing the effectiveness of mosquito attractants and repellents, a good olfactometer system, and optimized testing conditions, are essential. In this research, we demonstrated the usefulness of an olfactometer system, and optimized testing conditions for Aedes albopictus (Diptera: Culicidae). We found no significant difference in the biting activity of the insect between 8:00 and 22:00. Further...

Hao, Huiling; Sun, Jingcheng; Dai, Jianqing

2012-01-01

218

Trapping mosquitoes using milk products as odour baits in western Kenya  

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Abstract Background Ample evidence has shown that blood seeking mosquitoes locate their hosts by following odours produced by the hosts. Odour baited traps would therefore, provide a solution in controlling diseases spread by mosquitoes. Comparative studies were undertaken to determine the relative efficacies of two odour baits i.e. Limburger cheese and African traditional milk cream in trapping mosquitoes in the field in western Kenya. Method Comparative effica...

2010-01-01

219

Biocontrol of larval mosquitoes by Acilius sulcatus (Coleoptera: Dytiscidae)  

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Abstract Background Problems associated with resistant mosquitoes and the effects on non-target species by chemicals, evoke a reason to find alternative methods to control mosquitoes, like the use of natural predators. In this regard, aquatic coleopterans have been explored less compared to other insect predators. In the present study, an evaluation of the role of the larvae of Acilius sulcatus Linnaeus 1758 (Coleoptera: Dytiscidae) as predator of mosquito immatures ...

2008-01-01

220

Efficacy of Commercial Mosquito Traps in Capturing Phlebotomine Sand Flies (Diptera: Psychodidae) in Egypt.  

Science.gov (United States)

Four types of commercial mosquito control traps, the Mosquito Magnet Pro (MMP) the Sentinel 360 (S360), the BG-Sentinel (BGS), and the Mega-Catch Ultra (MCU), were compared with a standard Centers for Disease Control and Prevention (CDC) light trap for ef...

D. F. Hoel D. L. Kline J. A. Hogsette S. S. El-Hossary U. R. Bernier

2010-01-01

 
 
 
 
221

Female Anopheles gambiae antennae: increased transcript accumulation of the mosquito-specific odorant-binding-protein OBP2  

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Abstract Background New interventions are required to optimally and sustainably control the Anopheles sp. mosquitoes that transmit malaria and filariasis. The mosquito olfactory system is important in host seeking (transmission) and mate finding (reproduction). Understanding olfactory function could lead to development of control strategies based on repelling parasite-carrying mosquitoes or attracting them into a fatal trap. Findings Our initial focus i...

Hoffman Seth A; Aravind Lakshminarayanan; Velmurugan Soundarapandian

2012-01-01

222

Adult survivorship of the dengue mosquito Aedes aegypti varies seasonally in central Vietnam.  

Science.gov (United States)

The survival characteristics of the mosquito Aedes aegypti affect transmission rates of dengue because transmission requires infected mosquitoes to survive long enough for the virus to infect the salivary glands. Mosquito survival is assumed to be high in tropical, dengue endemic, countries like Vietnam. However, the survival rates of wild populations of mosquitoes are seldom measured due the difficulty of predicting mosquito age. Hon Mieu Island in central Vietnam is the site of a pilot release of Ae. aegypti infected with a strain of Wolbachia pipientis bacteria (wMelPop) that induces virus interference and mosquito life-shortening. We used the most accurate mosquito age grading approach, transcriptional profiling, to establish the survival patterns of the mosquito population from the population age structure. Furthermore, estimations were validated on mosquitoes released into a large semi-field environment consisting of an enclosed house, garden and yard to incorporate natural environmental variability. Mosquito survival was highest during the dry/cool (January-April) and dry/hot (May-August) seasons, when 92 and 64% of Hon Mieu mosquitoes had survived to an age that they were able to transmit dengue (12 d), respectively. This was reduced to 29% during the wet/cool season from September to December. The presence of Ae. aegypti older than 12 d during each season is likely to facilitate the observed continuity of dengue transmission in the region. We provide season specific Ae. aegypti survival models for improved dengue epidemiology and evaluation of mosquito control strategies that aim to reduce mosquito survival to break the dengue transmission cycle. PMID:24551251

Hugo, Leon E; Jeffery, Jason A L; Trewin, Brendan J; Wockner, Leesa F; Nguyen, Thi Yen; Nguyen, Hoang Le; Nghia, Le Trung; Hine, Emma; Ryan, Peter A; Kay, Brian H

2014-02-01

223

Adult Survivorship of the Dengue Mosquito Aedes aegypti Varies Seasonally in Central Vietnam  

Science.gov (United States)

The survival characteristics of the mosquito Aedes aegypti affect transmission rates of dengue because transmission requires infected mosquitoes to survive long enough for the virus to infect the salivary glands. Mosquito survival is assumed to be high in tropical, dengue endemic, countries like Vietnam. However, the survival rates of wild populations of mosquitoes are seldom measured due the difficulty of predicting mosquito age. Hon Mieu Island in central Vietnam is the site of a pilot release of Ae. aegypti infected with a strain of Wolbachia pipientis bacteria (wMelPop) that induces virus interference and mosquito life-shortening. We used the most accurate mosquito age grading approach, transcriptional profiling, to establish the survival patterns of the mosquito population from the population age structure. Furthermore, estimations were validated on mosquitoes released into a large semi-field environment consisting of an enclosed house, garden and yard to incorporate natural environmental variability. Mosquito survival was highest during the dry/cool (January-April) and dry/hot (May-August) seasons, when 92 and 64% of Hon Mieu mosquitoes had survived to an age that they were able to transmit dengue (12 d), respectively. This was reduced to 29% during the wet/cool season from September to December. The presence of Ae. aegypti older than 12 d during each season is likely to facilitate the observed continuity of dengue transmission in the region. We provide season specific Ae. aegypti survival models for improved dengue epidemiology and evaluation of mosquito control strategies that aim to reduce mosquito survival to break the dengue transmission cycle.

Hugo, Leon E.; Jeffery, Jason A. L.; Trewin, Brendan J.; Wockner, Leesa F.; Thi Yen, Nguyen; Le, Nguyen Hoang; Nghia, Le Trung; Hine, Emma; Ryan, Peter A.; Kay, Brian H.

2014-01-01

224

Predictors of mosquito net use in Ghana  

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Full Text Available Abstract Background During the past decade the malaria control community has been successful in dramatically increasing the number of households that own mosquito nets. However, as many as half of nets already in households go unused. This study examines the factors associated with use of nets owned in Ghana. Methods The data come from an August 2008 survey in Ghana of households with a pregnant woman or a guardian of a child under five, conducted during the rainy season. 1796 households were included in this analysis, which generated a sample of 1,852 mosquito nets. Using each net owned as the unit of analysis, multivariate logistic regression was used to examine the relationship of net used last night with 23 potentially explanatory variables having to do with characteristics of the household, of the respondent, and of the net. Odds Ratios, p-values, and confidence intervals were calculated for each variable to develop an explanatory model. Results The final multivariate model consisted of 10 variables statistically associated with whether or not the net was used the prior night: rural location, lower SES, not using coils for mosquito control, fewer nets in the household, newer nets and those in better condition, light blue colour, higher level of education of the guardian of the child under five, knowing that mosquitoes transmit malaria, and paying for the net instead of obtaining it free of charge. Conclusions The results of this study suggest that net use would increase in Ghana if coloured nets were made available in mass distributions as well as in the commercial market; if programmes emphasize that malaria is caused only by night-biting mosquitoes, and that nets protect against mosquitoes better than coils and need to be used even if coils are burning; if donated nets are replaced more frequently so that households have nets that are in good condition; and if there were support for the commercial market so that those who can afford to purchase a net and want to choose their own nets can do so.

Baume Carol A

2011-09-01

225

Culex Flavivirus and West Nile Virus Mosquito Coinfection and Positive Ecological Association in Chicago, United States  

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Culex flavivirus (CxFV) is an insect-specific flavivirus globally distributed in mosquitoes of the genus Culex. CxFV was positively associated with West Nile virus (WNV) infection in a case–control study of 268 mosquito pools from an endemic focus of WNV transmission in Chicago, United States. Specifically, WNV-positive Culex mosquito pools were four times more likely also to be infected with CxFV than were spatiotemporally matched WNV-negative pools. In addition, mosquito pools from reside...

2011-01-01

226

The Role of Innate Immunity in Conditioning Mosquito Susceptibility to West Nile Virus  

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Full Text Available Arthropod-borne viruses (arboviruses represent an emerging threat to human and livestock health globally. In particular, those transmitted by mosquitoes present the greatest challenges to disease control efforts. An understanding of the molecular basis for mosquito innate immunity to arbovirus infection is therefore critical to investigations regarding arbovirus evolution, virus-vector ecology, and mosquito vector competence. In this review, we discuss the current state of understanding regarding mosquito innate immunity to West Nile virus. We draw from the literature with respect to other virus-vector pairings to attempt to draw inferences to gaps in our knowledge about West Nile virus and relevant vectors.

Abhishek N. Prasad

2013-12-01

227

Wolbachia Enhances West Nile Virus (WNV) Infection in the Mosquito Culex tarsalis.  

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Novel strategies are required to control mosquitoes and the pathogens they transmit. One attractive approach involves maternally inherited endosymbiotic Wolbachia bacteria. After artificial infection with Wolbachia, many mosquitoes become refractory to infection and transmission of diverse pathogens. We evaluated the effects of Wolbachia (wAlbB strain) on infection, dissemination and transmission of West Nile virus (WNV) in the naturally uninfected mosquito Culex tarsalis, which is an important WNV vector in North America. After inoculation into adult female mosquitoes, Wolbachia reached high titers and disseminated widely to numerous tissues including the head, thoracic flight muscles, fat body and ovarian follicles. Contrary to other systems, Wolbachia did not inhibit WNV in this mosquito. Rather, WNV infection rate was significantly higher in Wolbachia-infected mosquitoes compared to controls. Quantitative PCR of selected innate immune genes indicated that REL1 (the activator of the antiviral Toll immune pathway) was down regulated in Wolbachia-infected relative to control mosquitoes. This is the first observation of Wolbachia-induced enhancement of a human pathogen in mosquitoes, suggesting that caution should be applied before releasing Wolbachia-infected insects as part of a vector-borne disease control program. PMID:25010200

Dodson, Brittany L; Hughes, Grant L; Paul, Oluwatobi; Matacchiero, Amy C; Kramer, Laura D; Rasgon, Jason L

2014-07-01

228

Don't Let the Bugs Bite: Preventing Dengue and Other Diseases Spread by Mosquitoes  

Centers for Disease Control (CDC) Podcasts

This year (2007) CDC is receiving a great many reports of cases of Dengue fever, which is spread by mosquitoes. This podcast discusses ways travelers to the tropics can protect themselves from mosquito bites.  Created: 12/10/2007 by National Center for the Prevention, Detection and Control of Infectious Diseases (NCPDCID).   Date Released: 12/10/2007.

2007-12-10

229

Nature, Nurture and Evolution of Intra-Species Variation in Mosquito Arbovirus Transmission Competence  

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Full Text Available Mosquitoes vary in their competence or ability to transmit arthropod-borne viruses (arboviruses. Many arboviruses cause disease in humans and animals. Identifying the environmental and genetic causes of variation in mosquito competence for arboviruses is one of the great challenges in public health. Progress identifying genetic (nature and environmental (nurture factors influencing mosquito competence for arboviruses is reviewed. There is great complexity in the various traits that comprise mosquito competence. The complex interactions between environmental and genetic factors controlling these traits and the factors shaping variation in Nature are largely unknown. The norms of reaction of specific genes influencing competence, their distributions in natural populations and the effects of genetic polymorphism on phenotypic variation need to be determined. Mechanisms influencing competence are not likely due to natural selection because of the direct effects of the arbovirus on mosquito fitness. More likely the traits for mosquito competence for arboviruses are the effects of adaptations for other functions of these competence mechanisms. Determining these other functions is essential to understand the evolution and distributions of competence for arboviruses. This information is needed to assess risk from mosquito-borne disease, predict new mosquito-arbovirus systems, and provide novel strategies to mitigate mosquito-borne arbovirus transmission.

Walter J. Tabachnick

2013-01-01

230

Host genotype by parasite genotype interactions underlying the resistance of anopheline mosquitoes to Plasmodium falciparum  

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Full Text Available Abstract Background Most studies on the resistance of mosquitoes to their malaria parasites focus on the response of a mosquito line or colony against a single parasite genotype. In natural situations, however, it may be expected that mosquito-malaria relationships are based, as are many other host-parasite systems, on host genotype by parasite genotype interactions. In such systems, certain hosts are resistant to one subset of the parasite's genotypes, while other hosts are resistant to a different subset. Methods To test for genotype by genotype interactions between malaria parasites and their anopheline vectors, different genetic backgrounds (families consisting of the F1 offspring of individual females of the major African vector Anopheles gambiae were challenged with several isolates of the human malaria parasite Plasmodium falciparum (obtained from naturally infected children in Kenya. Results Averaged across all parasites, the proportion of infected mosquitoes and the number of oocysts found in their midguts were similar in all mosquito families. Both indices of resistance, however, differed considerably among isolates of the parasite. In particular, no mosquito family was most resistant to all parasites, and no parasite isolate was most infectious to all mosquitoes. Conclusions These results suggest that the level of mosquito resistance depends on the interaction between its own and the parasite's genotype. This finding thus emphasizes the need to take into account the range of genetic diversity exhibited by mosquito and malaria field populations in ideas and studies concerning the control of malaria.

Gouagna Louis C

2005-01-01

231

Gene Expression Studies in Mosquitoes  

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Research on gene expression in mosquitoes is motivated by both basic and applied interests. Studies of genes involved in hematophagy, reproduction, olfaction, and immune responses reveal an exquisite confluence of biological adaptations that result in these highly-successful life forms. The requirement of female mosquitoes for a bloodmeal for propagation has been exploited by a wide diversity of viral, protozoan and metazoan pathogens as part of their life cycles. Identifying genes involved i...

Chen, Xlao-guang; Mathur, Geetika; James, Anthony A.

2008-01-01

232

Dinotefuran: a potential neonicotinoid insecticide against resistant mosquitoes.  

Science.gov (United States)

Because pyrethroid, organophosphate, and carbamate resistance is more and more developed in mosquitoes of medical importance, there is an urgent need for alternative insecticides for vector control. Dinotefuran, a new neonicotinoid insecticide commercialized by Mitsui Chemicals (Tokyo, Japan), could be a useful candidate in public health because it shows low mammalian toxicity and great insecticidal activity against a broad range of pests. In this study, the intrinsic toxicity of dinotefuran was evaluated by larval bioassay and topical application against different mosquito strains of Anopheles gambiae Giles, Culex quinquefasciatus Say, and Aedes aegypti L. having none, one, or several resistance mechanisms, respectively, to insecticides. The results showed that dinotefuran was less toxic than most of the commonly used insecticides (e.g., deltamethrin, carbosulfan, and temephos) against the susceptible mosquitoes tested (between 6- and 100-fold at the LD50 level). However, the toxicity of dinotefuran was not strongly affected by the presence of common resistance mechanism, i.e., kdr mutation and insensitive acetylcholinesterase (resistance ratio [RR] from 1.3 to 2.3). More interestingly, the carbamate-resistant strain of Cx. quinquefasciatus was significantly more affected by dinotefuran than the susceptible strain (RR = 0.70), probably because the insensitive acetylcholinesterase is less efficient to degrade nicotinic substrates than normal acetylcholinesterase. Despite the relatively low toxicity of dinotefuran against susceptible mosquitoes, the absence of cross-resistance with common insecticides (pyrethroids, carbamates, and organophosphates) makes neonicotinoids potential candidates for disease vector control, especially in area where mosquitoes are resistant to insecticides. PMID:15311465

Corbel, Vincent; Duchon, Stephane; Zaim, Morteza; Hougard, Jean-Marc

2004-07-01

233

Male reproductive biology of Aedes mosquitoes.  

Science.gov (United States)

Among Aedes mosquitoes are species responsible for transmission of serious pathogens to humans. To cope with the current threats to long-term effectiveness of the traditional vector control methods, non-conventional control strategies are being developed. These include autocidal control such as the release of sterile males (sterile insect technique) and the release of Wolbachia-infected males to induce sexual sterility (incompatible insect technique) and pathogen-refractory strain replacement variations using Wolbachia. Sterile male types of techniques particularly depend on released males' ability to successfully mate with wild females. For that reason, a good understanding of male mating biology, including a thorough understanding of the reproductive system and mating capacity, increases the likelihood of success of such genetic vector control programmes. Here we review the literature concerning the reproduction of Aedes mosquitoes with an emphasis on the male biology. We consider sexual maturation, mate finding, insemination, male reproductive capacity, and the occurrence of multiple matings. We also discuss which parameters are of greatest importance for the successful implementation of autocidal control methods and propose questions for future research. PMID:24308996

Oliva, Clelia F; Damiens, David; Benedict, Mark Q

2014-04-01

234

Señales físico químicas involucradas en la búsqueda de hospederos y en la inducción de picadura por mosquitos Physic-chemical signals involved in host localization and induction of disease vector mosquito bites  

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Full Text Available Las hembras de los mosquitos vectores de enfermedades utilizan señales físicas y químicas para localizar su fuente de alimentación sanguínea en hospederos vertebrados. Los mosquitos zoofílicos responden preferentemente al CO2 y al octenol liberados en la respiración y excreciones, mientras que los mosquitos antropofílicos responden al ácido láctico y a una variedad de compuestos del sudor. Estos compuestos son modificados por microrganismos saprófitos de las glándulas sebáceas de la piel. Otros factores presentes en las viviendas contribuyen a la integración de microsistemas constituidos por olores característicos, que explican los diferentes niveles de atracción de mosquitos y la focalización de la transmisión del paludismo a una porción de casas en localidades de áreas endémicas. La identificación de estos atrayentes químicos y sus moléculas receptoras en mosquitos puede ser utilizada como complemento de nuevos métodos para la vigilancia epidemiológica, para atraer a los mosquitos a trampas de colecta o para incrementar su contacto con insecticidas usados en su control, así como en la manipulación genética para desviar las picaduras de los mosquitos hacia otros hospederos vertebrados.Disease vector female mosquitoes respond to physic-chemical signals to localize vertebrate hosts for blood meals. Zoophylic mosquitoes preferentially respond to CO2 and octenol released in the breath and bodily fluids, while anthropophylic mosquitoes respond to lactic acid and a variety of sweat compounds. These compounds are modified by saprophytic microorganisms in the skin sebaceous glands. Other factors present in human dwellings contribute to the integration of microsystems with characteristic odors that have different attraction for mosquitoes, explaining the focalization of malaria transmission in few households in endemic areas. The identification of the chemical attractants and their molecular receptors could be used to complement new methods to attract mosquitoes to traps during epidemiological surveys, to increase their contact with insecticides in control interventions, and for genetic manipulation to divert mosquito bites towards other animal populations.

José Luis Torres-Estrada

2003-12-01

235

Mosquito Feeding Affects Larval Behaviour and Development in a Moth  

Science.gov (United States)

Organisms are attacked by different natural enemies present in their habitat. While enemies such as parasitoids and predators will kill their hosts/preys when they successfully attack them, enemies such as micropredators will not entirely consume their prey. However, they can still have important consequences on the performance and ecology of the prey, such as reduced growth, increased emigration, disease transmission. In this paper, we investigated the impact of a terrestrial micropredator, the yellow fever mosquito Aedes aegypti, on its unusual invertebrate host, the Egyptian cotton leaf worm, Spodoptera littoralis. Larvae developing in presence of mosquitoes showed a slower development and reached a smaller pupal weight when compared to a control without mosquitoes, apparently because of a reduced feeding time for larvae. In addition, larvae tended to leave the plant in presence of mosquitoes. These results suggest that mosquitoes act as micropredators and affects lepidopteran larvae behaviour and development. Ecological impacts such as higher risks of food depletion and longer exposure to natural enemies are likely to be costly consequences. The importance of this phenomenon in nature – the possible function as last resort when vertebrates are unavailable – and the evolutionary aspects are discussed.

Martel, Veronique; Schlyter, Fredrik; Ignell, Rickard; Hansson, Bill S.; Anderson, Peter

2011-01-01

236

REPELLENCY OF LANTANA CAMARA LEAVES SMOKE AGAINST FEMALE ANOPHELES MOSQUITOES  

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Full Text Available The study was done to investigate the Mosquito repellency properties of the smoke of Lantana camara in different solvents viz; methanol, ethyl acetate, ethanol and diethyl ether. Plant samples were dried, burned and extracted using various solvents. The extracts were concentrated using a Rota vapor and various concentrations ranging from 50ppm-1000ppm of the repellents were prepared and evaluated. Methanol extract at 400ppm concentration significantly gave the highest protection against the bites of female Anopheles mosquito (P> 0.01 for over 300 minutes. This extract yielded significantly the better protection time (P> 0.05. The methanol extract seemed to have a steady repellency over a longer period than the rest of the extracts. The results from this study shows that the plant Lantana camara can be used effectively to repel Anopheles mosquitoes, hence a great achievement in the development of safe organic repellants to control transmission of malaria by female anopheles mosquitoes. However, more research needs to be done to identify the specific compounds which are repelling the mosquitoes their structures and also mode of action.

Akumu Edwin O, Kebenei Sellah Anthoney Swamy T* and Ngule Chrispus Mutuku

2014-01-01

237

Mosquito vector abundance immediately before and after tropical storms Alma and Arthur, northern Belize, 2008 Abundancia de mosquitos vectores inmediatamente antes y después de las tormentas tropicales Alma y Arthur, norte de Belice, 2008  

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OBJECTIVE: To monitor adult mosquito abundance in northern Belize before/after the first tropical storm of the wet season to estimate the time required for development/recovery of potential vector populations; determine which species predominate post-storm; and compare the effectiveness of two types of mosquito traps-octenol-baited Mosquito Magnets® and U.S. Centers for Disease Control and Prevention (CDC) light traps (with/without octenol). METHODS: Field experiments were conducted in Orang...

Morrow, Meredith G.; Johnson, Richard N.; Jorge Polanco; Claborn, David M.

2010-01-01

238

Molecular discrimination of mosquito vectors and their pathogens.  

Science.gov (United States)

Mosquitoes are responsible for the transmission of pathogens that cause disease in over 400 million people each year worldwide. The capacity to transmit disease-causing pathogens can differ greatly between different species of the same genus or even populations of the same species. The geographic distribution and prevalence of vector-borne diseases is proportional to the distribution and prevalence of the relevant mosquito vectors. Furthermore, vector-borne pathogens can differ greatly in virulence and drug-resistance attributes. Accurate and rapid identification and discrimination of vector mosquito species and the pathogens they transmit are, therefore, essential components of disease prevention and control strategies, as well as of epidemiological and ecological research studies. Here, we review advances in diagnostic methods and tools for both vectors and pathogens which cause human disease. PMID:19817558

Sim, Shuzhen; Ramirez, José Luis; Dimopoulos, George

2009-10-01

239

European Surveillance for West Nile Virus in Mosquito Populations  

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Full Text Available A wide range of arthropod-borne viruses threaten both human and animal health either through their presence in Europe or through risk of introduction. Prominent among these is West Nile virus (WNV, primarily an avian virus, which has caused multiple outbreaks associated with human and equine mortality. Endemic outbreaks of West Nile fever have been reported in Italy, Greece, France, Romania, Hungary, Russia and Spain, with further spread expected. Most outbreaks in Western Europe have been due to infection with WNV Lineage 1. In Eastern Europe WNV Lineage 2 has been responsible for human and bird mortality, particularly in Greece, which has experienced extensive outbreaks over three consecutive years. Italy has experienced co-circulation with both virus lineages. The ability to manage this threat in a cost-effective way is dependent on early detection. Targeted surveillance for pathogens within mosquito populations offers the ability to detect viruses prior to their emergence in livestock, equine species or human populations. In addition, it can establish a baseline of mosquito-borne virus activity and allow monitoring of change to this over time. Early detection offers the opportunity to raise disease awareness, initiate vector control and preventative vaccination, now available for horses, and encourage personal protection against mosquito bites. This would have major benefits through financial savings and reduction in equid morbidity/mortality. However, effective surveillance that predicts virus outbreaks is challenged by a range of factors including limited resources, variation in mosquito capture rates (too few or too many, difficulties in mosquito identification, often reliant on specialist entomologists, and the sensitive, rapid detection of viruses in mosquito pools. Surveillance for WNV and other arboviruses within mosquito populations varies between European countries in the extent and focus of the surveillance. This study reviews the current status of WNV in mosquito populations across Europe and how this is informing our understanding of virus epidemiology. Key findings such as detection of virus, presence of vector species and invasive mosquito species are summarized, and some of the difficulties encountered when applying a cost-effective surveillance programme are highlighted.

Nicholas Johnson

2013-10-01

240

Activation of Akt Signaling Reduces the Prevalence and Intensity of Malaria Parasite Infection and Lifespan in Anopheles stephensi Mosquitoes  

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Malaria (Plasmodium spp.) kills nearly one million people annually and this number will likely increase as drug and insecticide resistance reduces the effectiveness of current control strategies. The most important human malaria parasite, Plasmodium falciparum, undergoes a complex developmental cycle in the mosquito that takes approximately two weeks and begins with the invasion of the mosquito midgut. Here, we demonstrate that increased Akt signaling in the mosquito midgut disrupts parasite ...

2010-01-01

 
 
 
 
241

Interdependence of domestic malaria prevention measures and mosquito-human interactions in urban Dar es Salaam, Tanzania  

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Abstract Background Successful malaria vector control depends on understanding behavioural interactions between mosquitoes and humans, which are highly setting-specific and may have characteristic features in urban environments. Here mosquito biting patterns in Dar es Salaam, Tanzania are examined and the protection against exposure to malaria transmission that is afforded to residents by using an insecticide-treated net (ITN) is estimated. Methods Mosquito biti...

Geissbühler Yvonne; Chaki Prosper; Emidi Basiliana; Govella Nicodemus J; Shirima Rudolf; Mayagaya Valeliana; Mtasiwa Deo; Mshinda Hassan; Fillinger Ulrike; Lindsay Steven W; Kannady Khadija; de Castro Marcia; Tanner Marcel; Killeen Gerry F

2007-01-01

242

Eliciting Renal Failure in Mosquitoes with a Small-Molecule Inhibitor of Inward-Rectifying Potassium Channels  

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Mosquito-borne diseases such as malaria and dengue fever take a large toll on global health. The primary chemical agents used for controlling mosquitoes are insecticides that target the nervous system. However, the emergence of resistance in mosquito populations is reducing the efficacy of available insecticides. The development of new insecticides is therefore urgent. Here we show that VU573, a small-molecule inhibitor of mammalian inward-rectifying potassium (Kir) channels, inhibits a Kir c...

2013-01-01

243

Mosquito larvicidal and antimicrobial activity of protein of Solanum villosum leaves  

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Abstract Background Mosquitoes are associated with the transmission of malaria, dengue, Japanese encephalitis, filariasis and other viral diseases throughout the globe, apart from being a nuisance pest. Biological control alone or as a part of integrated vector management stands to be a better alternative to the chemical controls aimed against pest mosquitoes. At the same time it is necessary to control bacteria by synthetic or natural means (plant products). Hence the presen...

2008-01-01

244

Attracting, trapping and killing disease-transmitting mosquitoes using odor-baited stations - The Ifakara Odor-Baited Stations  

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Abstract Background To accelerate efforts towards control and possibly elimination of mosquito-borne diseases such as malaria and lymphatic filariasis, optimally located outdoor interventions could be used to complement existing intradomicilliary vector control methods such as house spraying with insecticides and insecticidal bednets. Methods We describe a new odor-baited station for trapping, contaminating and killing disease-transmitting mosquitoes. This devic...

Okumu Fredros O; Madumla Edith P; John Alex N; Lwetoijera Dickson W; Sumaye Robert D

2010-01-01

245

Synergy in Efficacy of Fungal Entomopathogens and Permethrin against West African Insecticide-Resistant Anopheles gambiae Mosquitoes  

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Background: Increasing incidences of insecticide resistance in malaria vectors are threatening the sustainable use of contemporary chemical vector control measures. Fungal entomopathogens provide a possible additional tool for the control of insecticide-resistant malaria mosquitoes. This study investigated the compatibility of the pyrethroid insecticide permethrin and two mosquito-pathogenic fungi, Beauveria bassiana and Metarhizium anisopliae, against a laboratory colony and field population...

2010-01-01

246

Review: artificial container-breeding mosquitoes and cemeteries: a perfect match.  

Science.gov (United States)

Artificial container-breeding mosquitoes, such as Aedes aegypti, Ae. albopictus, and Culex pipiens, are well-recognized vectors of diseases throughout the world. Cemeteries are considered major sources of mosquitoes and the results of more than 30 studies concerning mosquitoes in cemeteries have been published over the last decade. The characteristics of these environments in regard to the availability of resources for mosquito development were discussed. Also, studies about early detection of Aedes vectors, ecological issues, and mosquito control performed in cemeteries were reviewed. Among 31 mosquito species found breeding in cemeteries from 16 countries, the invasive Ae. aegypti and Ae. albopictus were the most frequent ones. Species of the genus Ochlerotatus, Culex, Toxorhynchites, Culiseta, Armigeres, Lutzia, Uranotaenia, and Tripteroides were also reported. Overall, cemeteries are highly suitable habitats for artificial container-breeding mosquitoes due to the great availability of the different resources that they need (i.e. sugar substances, blood, shelter and water-filled containers). In addition, these places are mostly ideal settings to perform studies in urbanized areas because of high mosquito abundance, heterogeneity of macro- and microhabitats, and an easier access in comparison with private premises. However, the feasibility of a cemetery as a study area must be evaluated in each case considering the objectives of the study and cemetery characteristics. PMID:17300639

Vezzani, Darío

2007-02-01

247

Susceptibility Status of Anopheles sundaicus Mosquitoes Against Insecticides Cypermethrin in Garut Regency  

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Full Text Available At the time of high vector populations and malaria transmission is in progress, it is necessary to use insecticides to control vector using the house spraying. To get the results as objective the eradication of the vector that is able to suppress the vector population so that no longer play a role in malaria transmission, the insecticide used should be effective against mosquitoes and the mosquitoes are still susceptible to the insecticide used. To determine the level of malaria vector mosquito susceptibility to insecticides, in the terri-tory of Garut district has conducted susceptibility tests of Anopheles sundaicus mosquitoes to insecticides Cypermethrin held in November up to December 2008. Mosquitoes tested were captured in the form of larvae from ponds and estuaries in Karyamukti Cibalong Garut, and then reared in the field insektarium. The adult level were then tested for their susceptibility. Mosquito susceptibility tests conducted using the WHO Susceptibility Test Kit as many as four repetitions performed simultaneously, while the insecticide used in the form of imprag-nated paper with a dose of 0.05%. From tests it is known that mosquito mortality rate up to 100% test. This indicates that the mosquito An. sundaicus in Garut regency of West Java, is still susceptible to the insecticide Cypermenthrin. Therefore, it can still be used in the eradication of malaria vectors in the recommended dosage of 0.20 g/m2.

Nunung Seniawati

2010-06-01

248

PERCEPTIONS REGARDING MOSQUITO BORNE DISEASES IN AN URBAN AREA OF RAJKOT CITY  

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Full Text Available Background: Mosquito borne diseases is a growing urban problem because of unplanned urbanization, industrialization and excessive population growth coupled with rural to urban migration. For developing a suitable and effective health education strategy, it is inevitable to understand the level of knowledge of the community, their attitude and practices regarding mosquito borne diseases. Materials and Methods: The present study was carried out in an urban field practice area of Urban Health Centre in Rajkot city. Total 500 houses were selected for study by systematic random sampling. Data was collected using a semi-structured questionnaire during transmission season of vector borne diseases. The results were analyzed using the SPSS 17 software. Results: 90% respondents agreed that mosquitoes are a problem. 30.4% didn?t know breeding sites of mosquitoes. Only 11.6% of people associated clean water collections with mosquito breeding. Regarding diseases transmitted by mosquito, 62% answered malaria, 37.4% were not aware and 8.8% people mentioned about Filariasis, Dengue or Japanese encephalitis. 4.7% granted mosquito control as responsibility of community. 61.4 % were using repellents for prevention against mosquito bites and 39% not taking any preventive measure. 67.8% consulted private practitioner for treatment. Conclusion: Intensified efforts towards creating public awareness and mobilizing the community regarding the preventive measures they can take are needed. [National J of Med Res 2011; 1(2.000: 45-47

Amul B. Patel

2011-04-01

249

A simple non-powered passive trap for the collection of mosquitoes for arbovirus surveillance.  

Science.gov (United States)

Mosquitoes often are collected as part of an arbovirus surveillance program. However, trapping and processing of mosquitoes for arbovirus detection is often costly and difficult in remote areas. Most traps, such as the gold standard Center for Disease control light trap, require batteries that must be charged and changed overnight. To overcome this issue we have developed several passive traps for collection of mosquitoes that have no power requirements. The passive traps capture mosquitoes as they follow a CO2 plume up a polyvinyl chloride pipe leading to a clear chamber consisting of a plastic crate. We believe the translucent, clear windows created by the crate inhibits escape. Once inside the crate mosquitoes readily feed on honey-treated Flinders Technology Associates cards that then can be processed by polymerase chain reaction for viral ribonucleic acid. Of the two designs tested, the box or crate-based passive trap (passive box trap, PBT) generally caught more mosquitoes than the cylinder trap. In Latin square field trials in Cairns and Florida, PBTs collected mosquitoes at rates of 50 to 200% of Center for Disease Control model 512 light traps. Mosquito collections by PBTs can be increased by splitting the CO2 gas line so it services two traps, or by placing an octenol lure to the outside of the box. Very large collections can lead to crowding at honey-treated cards, reducing feeding rates. Addition of fipronil to the honey killed mosquitoes and did not impact feeding rates nor the ability to detect Kunjin viral ribonucleic acid by polymerase chain reaction; this could be used to minimize crowding affects on feeding caused by large collections. The passive traps we developed are made from inexpensive, commonly available materials. Passive traps may thus be suitable for collection of mosquitoes and potentially other hematophagous dipterans for pathogen surveillance. PMID:23427669

Ritchie, Scott A; Cortis, Giles; Paton, Christopher; Townsend, Michael; Shroyer, Donald; Zborowski, Paul; Hall-Mendelin, Sonja; Van Den Hurk, Andrew F

2013-01-01

250

Contrasting patterns of tolerance between chemical and biological insecticides in mosquitoes exposed to UV-A.  

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Mosquitoes are vectors of major human diseases, such as malaria, dengue or yellow fever. Because no efficient treatments or vaccines are available for most of these diseases, control measures rely mainly on reducing mosquito populations by the use of insecticides. Numerous biotic and abiotic factors are known to modulate the efficacy of insecticides used in mosquito control. Mosquito breeding sites vary from opened to high vegetation covered areas leading to a large ultraviolet gradient exposure. This ecological feature may affect the general physiology of the insect, including the resistance status against insecticides. In the context of their contrasted breeding sites, we assessed the impact of low-energetic ultraviolet exposure on mosquito sensitivity to biological and chemical insecticides. We show that several mosquito detoxification enzyme activities (cytochrome P450, glutathione S-transferases, esterases) were increased upon low-energy UV-A exposure. Additionally, five specific genes encoding detoxification enzymes (CYP6BB2, CYP6Z7, CYP6Z8, GSTD4, and GSTE2) previously shown to be involved in resistance to chemical insecticides were found over-transcribed in UV-A exposed mosquitoes, revealed by RT-qPCR experiments. More importantly, toxicological bioassays revealed that UV-exposed mosquitoes were more tolerant to four main chemical insecticide classes (DDT, imidacloprid, permethrin, temephos), whereas the bioinsecticide Bacillus thuringiensis subsp. israelensis (Bti) appeared more toxic. The present article provides the first experimental evidence of the capacity of low-energy UV-A to increase mosquito tolerance to major chemical insecticides. This is also the first time that a metabolic resistance to chemical insecticides is linked to a higher susceptibility to a bioinsecticide. These results support the use of Bti as an efficient alternative to chemical insecticides when a metabolic resistance to chemicals has been developed by mosquitoes. PMID:23911355

Tetreau, Guillaume; Chandor-Proust, Alexia; Faucon, Frédéric; Stalinski, Renaud; Akhouayri, Idir; Prud'homme, Sophie M; Raveton, Muriel; Reynaud, Stéphane

2013-09-15

251

One Injection of DsRed Followed by Bites from Transgenic Mosquitoes Producing DsRed in the Saliva Elicits a High Titer of Antibody in Mice  

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It has been proposed that transgenic mosquitoes can be used as a “flying syringe” for infectious disease control. We succeeded in generating a transgenic (TG) mosquito, Anopheles stephensi, excreting and discharging DsRed in saliva. DsRed was deposited on the membrane where the TG mosquito probed with its proboscis. Repeated feeding by the TG mosquitoes induced anti-DeRed as well as anti-SG antibodies in mice. This indicates that the TG mosquitoes can immunize the animal. Moreover, in thi...

Matsuoka, Hiroyuki; Sano, Gen-ichiro; Hattori, Ryuta; Tomita, Hiroyuki; Yamamoto, Daisuke S.; Hirai, Makoto

2012-01-01

252

Señales físico químicas involucradas en la búsqueda de hospederos y en la inducción de picadura por mosquitos / Physic-chemical signals involved in host localization and induction of disease vector mosquito bites  

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Full Text Available SciELO Public Health | Language: Spanish Abstract in spanish Las hembras de los mosquitos vectores de enfermedades utilizan señales físicas y químicas para localizar su fuente de alimentación sanguínea en hospederos vertebrados. Los mosquitos zoofílicos responden preferentemente al CO2 y al octenol liberados en la respiración y excreciones, mientras que los m [...] osquitos antropofílicos responden al ácido láctico y a una variedad de compuestos del sudor. Estos compuestos son modificados por microrganismos saprófitos de las glándulas sebáceas de la piel. Otros factores presentes en las viviendas contribuyen a la integración de microsistemas constituidos por olores característicos, que explican los diferentes niveles de atracción de mosquitos y la focalización de la transmisión del paludismo a una porción de casas en localidades de áreas endémicas. La identificación de estos atrayentes químicos y sus moléculas receptoras en mosquitos puede ser utilizada como complemento de nuevos métodos para la vigilancia epidemiológica, para atraer a los mosquitos a trampas de colecta o para incrementar su contacto con insecticidas usados en su control, así como en la manipulación genética para desviar las picaduras de los mosquitos hacia otros hospederos vertebrados. Abstract in english Disease vector female mosquitoes respond to physic-chemical signals to localize vertebrate hosts for blood meals. Zoophylic mosquitoes preferentially respond to CO2 and octenol released in the breath and bodily fluids, while anthropophylic mosquitoes respond to lactic acid and a variety of sweat com [...] pounds. These compounds are modified by saprophytic microorganisms in the skin sebaceous glands. Other factors present in human dwellings contribute to the integration of microsystems with characteristic odors that have different attraction for mosquitoes, explaining the focalization of malaria transmission in few households in endemic areas. The identification of the chemical attractants and their molecular receptors could be used to complement new methods to attract mosquitoes to traps during epidemiological surveys, to increase their contact with insecticides in control interventions, and for genetic manipulation to divert mosquito bites towards other animal populations.

José Luis, Torres-Estrada; Mario H, Rodríguez.

253

Señales físico químicas involucradas en la búsqueda de hospederos y en la inducción de picadura por mosquitos / Physic-chemical signals involved in host localization and induction of disease vector mosquito bites  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish Las hembras de los mosquitos vectores de enfermedades utilizan señales físicas y químicas para localizar su fuente de alimentación sanguínea en hospederos vertebrados. Los mosquitos zoofílicos responden preferentemente al CO2 y al octenol liberados en la respiración y excreciones, mientras que los m [...] osquitos antropofílicos responden al ácido láctico y a una variedad de compuestos del sudor. Estos compuestos son modificados por microrganismos saprófitos de las glándulas sebáceas de la piel. Otros factores presentes en las viviendas contribuyen a la integración de microsistemas constituidos por olores característicos, que explican los diferentes niveles de atracción de mosquitos y la focalización de la transmisión del paludismo a una porción de casas en localidades de áreas endémicas. La identificación de estos atrayentes químicos y sus moléculas receptoras en mosquitos puede ser utilizada como complemento de nuevos métodos para la vigilancia epidemiológica, para atraer a los mosquitos a trampas de colecta o para incrementar su contacto con insecticidas usados en su control, así como en la manipulación genética para desviar las picaduras de los mosquitos hacia otros hospederos vertebrados. Abstract in english Disease vector female mosquitoes respond to physic-chemical signals to localize vertebrate hosts for blood meals. Zoophylic mosquitoes preferentially respond to CO2 and octenol released in the breath and bodily fluids, while anthropophylic mosquitoes respond to lactic acid and a variety of sweat com [...] pounds. These compounds are modified by saprophytic microorganisms in the skin sebaceous glands. Other factors present in human dwellings contribute to the integration of microsystems with characteristic odors that have different attraction for mosquitoes, explaining the focalization of malaria transmission in few households in endemic areas. The identification of the chemical attractants and their molecular receptors could be used to complement new methods to attract mosquitoes to traps during epidemiological surveys, to increase their contact with insecticides in control interventions, and for genetic manipulation to divert mosquito bites towards other animal populations.

José Luis, Torres-Estrada; Mario H, Rodríguez.

254

Evaluation of commercial products for personal protection against mosquitoes.  

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Human landing catch studies were conducted in a semi-field setting to determine the efficacy of seven commercial products used for personal protection against mosquitoes. Experiments were conducted in two empty, insecticide free, mesh-enclosed greenhouses, in Israel, with either 1500 Aedes albopictus or 1500 Culex pipiens released on consecutive study nights. The products tested in this study were the OFF!(®) Clip-On™ Mosquito Repellent (Metofluthrin 31.2%) and the Terminix(®) ALLCLEAR(®) Sidekick Mosquito Repeller (Cinnamon oil 10.5%; Eugenol 13%; Geranium oil 21%; Peppermint 5.3%; Lemongrass oil 2.6%), which are personal diffusers; Super Band™ Wristband (22% Citronella oil) and the PIC(®) Citronella Plus Wristband (Geraniol 15%; Lemongrass oil 5%, Citronella oil 1%); the Sonic Insect Repeller Keychain; the Mosquito Guard Patch (Oil of Lemon Eucalyptus 80mg), an adhesive-backed sticker for use on textiles; and the Mosquito Patch (vitamin B1 300mg), a transdermal patch. It was determined that the sticker, transdermal patch, wristbands and sonic device did not provide significant protection to volunteers compared with the mosquito attack rate on control volunteers who were not wearing a repellent device. The personal diffusers: - OFF!(®) Clip-On™ and Terminix(®) ALLCLEAR(®) Sidekick - provided superior protection compared with all other devices in this study. These diffusers reduced biting on the arms of volunteers by 96.28% and 95.26% respectively, for Ae. albopictus, and by 94.94% and 92.15% respectively, for Cx. pipiens. In a second trial conducted to compare these devices directly, biting was reduced by the OFF!(®) Clip-On™ and the Terminix(®) ALLCLEAR(®) by 87.55% and 92.83%, respectively, for Ae. albopictus, and by 97.22% and 94.14%, respectively, for Cx. pipiens. There was no significant difference between the performances of the two diffusers for each species. PMID:23092689

Revay, Edita E; Junnila, Amy; Xue, Rui-De; Kline, Daniel L; Bernier, Ulrich R; Kravchenko, Vasiliy D; Qualls, Whitney A; Ghattas, Nina; Müller, Günter C

2013-02-01

255

Plasmodium knowlesi in humans, macaques and mosquitoes in peninsular Malaysia  

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Full Text Available Abstract Background Since a large focus of human infection with Plasmodium knowlesi, a simian malaria parasite naturally found in long-tailed and pig tailed macaques, was reported in Sarawak, Malaysian Borneo, it was pertinent to study the situation in peninsular Malaysia. A study was thus initiated to screen human cases of Plasmodium malariae using molecular techniques, to determine the presence of P. knowlesi in non- human primates and to elucidate its vectors. Methods Nested polymerase chain reaction (PCR was used to identify all Plasmodium species present in the human blood samples sent to the Parasitology laboratory of Institute for Medical Research. At the same time, non-human primates were also screened for malaria parasites and nested PCR was carried out to determine the presence of P. knowlesi. Mosquitoes were collected from Pahang by human landing collection and monkey-baited-traps situated on three different levels. All mosquitoes were identified and salivary glands and midguts of anopheline mosquitoes were dissected to determine the presence of malaria parasites and nested PCR was carried out on positive glands. Sequencing of the csp genes were carried on P. knowlesi samples from humans, monkeys and mosquitoes, positive by PCR. Results and Discussion Plasmodium knowlesi was detected in 77 (69.37% of the 111 human samples, 10 (6.90% of the 145 monkey blood and in 2 (1.7% Anopheles cracens. Sequence of the csp gene clustered with other P. knowlesi isolates. Conclusion Human infection with Plasmodium knowlesi is occurring in most states of peninsular Malaysia. An. cracens is the main vector. Economic exploitation of the forest is perhaps bringing monkeys, mosquitoes and humans into increased contact. A single bite from a mosquito infected with P. knowlesi is sufficient to introduce the parasite to humans. Thus, this zoonotic transmission has to be considered in the future planning of malaria control.

NorParina Ismail

2008-08-01

256

Avaliação de termonebulizações de propoxur contra mosquitos através de testes biológicos Evaluation of thermonebulization of propoxur used against mosquitoes by means of biological tests  

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A eficácia de termonebulização do inseticida propoxur no controle de Aedes aegypti foi avaliada através de testes realizados no Município de São José do Rio Preto, Estado de São Paulo (Brasil). Estudos comparativos monitorados por mosquitos - Culex quinquefasciatus - presos em gaiolas, indicaram que o horário de aplicação do inseticida teve forte influência na mortalidade dos mosquitos, que não ultrapassou 43% quando as aplicações foram feitas entre 17 h e 17:30 h, enquanto que...

1988-01-01

257

Rural buyers' perception about mosquito repellants  

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Full Text Available Mosquito repellants prevent mosquito bites and prevention of "man-mosquito contact" is a critical factor in transmission and spread of any disease through mosquitoes particularly in rural area. There has been a long standing 'bias' towards rural buyers. The rural markets are considered rigid in the nature but it is not the case in real sense. Marketing to rural buyers is not only a challenge to the marketers but to the manufacturers, communicators, national planners and economists as well. That is why it has been necessary to understand the various aspects of selected rural areas and consumption pattern for such a fast growing market i.e. mosquito repellants and rural buyers’ perception towards such urban products. The present paper aims to find out the factors influencing the purchase decisions of rural buyers for mosquito repellants and to study the perceptions of present and potential rural buyers' of selected mosquito repellant brands.

D. MEHTA

2010-06-01

258

Temporal and spatial habitat preferences and biotic interactions between mosquito larvae and antagonistic crustaceans in the field.  

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Investigations on natural antagonists of mosquito larvae found that micro-crustaceans (e.g., Cladocera) control mosquito populations under experimental conditions. However, their relevance for mosquito control under field situations remains widely unclear because important information about habitat preferences and time of occurrence of crustaceans and mosquito larvae are still missing. In order to fill this knowledge gap, a field study was undertaken in different wetland areas of Saxony, Germany, in different habitats (i.e., grassland, forest, and reed-covered wetlands). We found negative interactions between larvae of Ae. vexans and predatory Cyclopoida (Crustacean: Copepoda), which both were dominant during the first two weeks of hydroperiod, at ponds located at grassland habitats. Larvae of Cx. pipiens were spatially associated with competing Cladocera, but they colonized ponds more rapidly. Populations of Cladocera established from the third week of hydroperiod and prevented Cx. pipiens colonization thereafter. Ostracoda were highly abundant during the whole hydroperiod, but their presence was restricted to habitats of reed-covered wetland at one geographical area. Mosquito larvae hardly occurred at those ponds. In general, we found that ponds at the reed-covered wetlands provided better conditions for the initial development of crustaceans and hence, mosquito larval colonization was strongly inhibited. Grassland habitat, in contrast, favored early development of mosquito larvae. This study showed that micro-crustaceans are relevant for mosquito management but their impact on mosquito larvae varies between species and depends on environmental conditions. PMID:24820562

Kroeger, Iris; Liess, Matthias; Duquesne, Sabine

2014-06-01

259

Preventing the Spread of Malaria and Dengue Fever Using Genetically Modified Mosquitoes  

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In this candid interview, Anthony A. James explains how mosquito genetics can be exploited to control malaria and dengue transmission. Population replacement strategy, the idea that transgenic mosquitoes can be released into the wild to control disease transmission, is introduced, as well as the concept of genetic drive and the design criterion for an effective genetic drive system. The ethical considerations of releasing genetically-modified organisms into the wild are also discussed.

James, Anthony A.

2007-01-01

260

Wolbachia Induces Density-Dependent Inhibition to Dengue Virus in Mosquito Cells  

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Wolbachia is a maternal transmitted endosymbiotic bacterium that is estimated to infect up to 65% of insect species. The ability of Wolbachia to both induce viral interference and spread into mosquito vector population makes it possible to develop Wolbachia as a biological control agent for dengue control. While Wolbachia induces resistance to dengue virus in the transinfected Aedes aegypti mosquitoes, a similar effect was not observed in Aedes albopictus, which naturally carries Wolbachia in...

Lu, Peng; Bian, Guowu; Pan, Xiaoling; Xi, Zhiyong

2012-01-01

 
 
 
 
261

Field Cage Studies and Progressive Evaluation of Genetically-Engineered Mosquitoes  

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The absence of a commercially-available dengue vaccine or anti-viral drug makes control of Aedes aegypti, the principal dengue mosquito vector, the only available method to prevent this disease. Sustained, effective application of vector control, however, has been difficult and this led to the call for innovative strategies, including genetic approaches. Here, the authors investigated the ability of a genetically-engineered strain of Ae. aegypti to eliminate wild mosquito populations in large...

2013-01-01

262

An Integrated Linkage, Chromosome, and Genome Map for the Yellow Fever Mosquito Aedes aegypti  

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About half of the human population is under risk of dengue infection. Because of the absence of a vaccine or drug treatment, the prevention of this disease largely relies on controlling its major vector mosquito Aedes aegypti. Availability of the complete genome sequence for this mosquito offers the potential to help in the identification of novel disease control strategies. An efficient vector of arboviruses, Ae. aegypti is also a convenient model for laboratory studies. A number of genetic ...

Timoshevskiy, Vladimir A.; Severson, David W.; Debruyn, Becky S.; Black, William C.; Sharakhov, Igor V.; Sharakhova, Maria V.

2013-01-01

263

Higher Mosquito Production in Low-Income Neighborhoods of Baltimore and Washington, DC: Understanding Ecological Drivers and Mosquito-Borne Disease Risk in Temperate Cities  

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Full Text Available Mosquito-vectored pathogens are responsible for devastating human diseases and are (reemerging in many urban environments. Effective mosquito control in urban landscapes relies on improved understanding of the complex interactions between the ecological and social factors that define where mosquito populations can grow. We compared the density of mosquito habitat and pupae production across economically varying neighborhoods in two temperate U.S. cities (Baltimore, MD and Washington, DC. Seven species of mosquito larvae were recorded. The invasive Aedes albopictus was the only species found in all neighborhoods. Culex pipiens, a primary vector of West Nile virus (WNV, was most abundant in Baltimore, which also had more tire habitats. Both Culex and Aedes pupae were more likely to be sampled in neighborhoods categorized as being below median income level in each city and Aedes pupae density was also greater in container habitats found in these lower income neighborhoods. We infer that lower income residents may experience greater exposure to potential disease vectors and Baltimore residents specifically, were at greater risk of exposure to the predominant WNV vector. However, we also found that resident-reported mosquito nuisance was not correlated with our measured risk index, indicating a potentially important mismatch between motivation needed to engage participation in control efforts and the relative importance of control among neighborhoods.

Danielle Bodner

2013-04-01

264

Culicinae (Diptera: Culicidae Mosquitoes in Chabahar County, Sistan and Baluchistan Province, Southeastern Iran  

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Full Text Available   Abstract Background: Mosquito-borne diseases are a major public health threat in Iran. The objective of this study was to de­ter­mine the fauna of culicinae mosquitoes for future mosquito control programs."nMethods: Three genera and eleven species of the subfamily Culicinae (Diptera: Culicidae were collected by dipping tech­nique and identified in Chabahar County, Sistan and Baluchistan Province, southeastern Iran, during January, Feb­ru­ary, and March 2007."nResults: The collected species included:  Aedes vexans (new occurrence record for the province, Culex  arbieeni, Cx. bitaeniorhynchus, Cx. deserticola, Cx. hortensis, Cx. perexiguus, Cx. pipiens, Cx.  pseudovishnui, Cx. pusillus, Cx. quinquefasciatus, Cx. sinaiticus, Cx. theileri, Cx. tritaeniorhynchus, Culiseta longiareolata, Ochlerotatus cabal­lus, Oc. caspius, and Uranotaenia unguiculata."nConclusion: Our observations indicate that, in South of Iran hot and wet climatic conditions support the persistence of culicinae mosquitoes. As our study, regular monitoring of culicinae mosquitoes in this area could be the most use­ful for mosquito control and mosquito-borne disease prevention.

SH Moosa-Kazemi

2009-07-01

265

Bacteria as a source of oviposition attractant for Aedes aegypti mosquitoes.  

Science.gov (United States)

Since a safe and effective mass vaccination program against dengue fever is not presently available, a good way to prevent and control dengue outbreaks depends mainly on controlling the mosquito vectors. Aedes aegypti mosquito populations can be monitored and reduced by using ovitraps baited with organic infusions. A series of laboratory experiments were conducted which demonstrated that the bacteria in bamboo leaf infusion produce volatile attractants and contact chemical stimulants attractive to the female mosquitoes. The results showed that the female mosquitoes laid most of their eggs (59.9 ± 8.1 vs 2.9 ± 2.8 eggs, Pbamboo leaf infusions when compared to distilled water. When the fresh infusion was filtered with a 0.45 ?m filter membrane, the female mosquitoes laid significantly more eggs (64.1 ± 6.6 vs 4.9 ± 2.6 eggs, Pbamboo leaf infusion serve as potent oviposition stimulants for gravid Aedes mosquitoes. Aedes aegypti laid significantly more eggs (63.3 ± 6.5 vs 3.1 ± 2.4 eggs, P<0.001) in bacteria suspension compared to sterile R2A medium. Our results suggest microbial activity has a role in the production of odorants that mediate the oviposition response of gravid mosquitoes. PMID:24862053

Arbaoui, A A; Chua, T H

2014-03-01

266

Measurement of landing mosquito density on humans.  

Science.gov (United States)

In traditional vector surveillance systems, adult mosquito density and the rate of mosquito-human host contact are estimated from the mosquito numbers captured in mechanical traps. But the design of the traps, their placement in the habitat and operating time, microclimate, and other environmental factors bias mosquito responses such that trapped mosquito numbers may be at variance with the numbers actually making human contact. As an alternative to mechanical traps, direct measurement of landing mosquito density enables real-time estimation of the mosquito-human-host-contact parameter. Based on this paradigm, we studied methods to measure mosquito landing responses to a human host. Our results showed: (a) an 18% difference (Planding responses of Culex nigripalpus Theobald and Cx. quinquefasciatus Say with increased sampling time; (c) no difference (P>0.55) in the average number of Ae. albopictus landing on the arm (8.6±1.6min(-1)) compared with the leg (9.2±2.5min(-1)) of the same human subject; (d) differences among day-to-day landing patterns for the mosquito species we studied but measurable periodicity (Planding mosquito density from air temperature (Planding density on a human subject. PMID:24769003

Barnard, Donald R; Dickerson, Catherine Z; Murugan, Kadarkarai; Xue, Rui-De; Kline, Daniel L; Bernier, Ulrich R

2014-08-01

267

Toxicological Effects of Inhaled Mosquito Coil Smoke on the Rat Spleen: A Haematological and Histological Study  

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The effect of inhaling mosquito coil smoke on the haematology and histology of the rats spleen was studied. A total of 30 albino rats of the Wister strain were used in this study, they were divided into six groups of five rats each. Rats in Group I served as control (no exposure to mosquito coil smoke). While Groups II-VI were exposed to mosquito coil smoke for 12 h, 7, 14, 21 and 28 days, respectively. At the end of each experimental period, blood was collected from each rat for the analysis...

Garba, S. H.; Shehu, M. M.; Adelaiye, A. B.

2007-01-01

268

Larval midgut modifications associated with Bti resistance in the yellow fever mosquito using proteomic and transcriptomic approaches  

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Abstract Background Bacillus thuringiensis var. israelensis (Bti) is a natural larval mosquito pathogen producing pore-forming toxins targeting the midgut of Diptera larvae. It is used worldwide for mosquito control. Resistance mechanisms of an Aedes aegypti laboratory strain selected for 30 generations with field-collected leaf litter containing Bti toxins were investigated in larval midguts at two levels: 1. gene transcription us...

Tetreau Guillaume; Bayyareddy Krishnareddy; Jones Christopher M; Stalinski Renaud; Riaz Muhammad A; Paris Margot; David Jean-Philippe; Adang Michael J; Després Laurence

2012-01-01

269

Field evaluation of four widely used mosquito traps in Central Europe  

Science.gov (United States)

Background To monitor adult mosquitoes several trapping devices are available. These are differently constructed and use various mechanisms for mosquito attraction, thus resulting in different trapping sensitivities and efficacies for the various species. Mosquito monitoring and surveillance programs in Europe use various types of mosquito traps, but only a few comparisons have been conducted so far. This study compared the performance of four commercial trapping devices, which are commonly used in Europe. Methods Four different traps, Biogents Sentinel trap (BG trap), Heavy Duty Encephalitis Vector Survey trap (EVS trap), Centres for Disease Control miniature light trap (CDC trap) and Mosquito Magnet Patriot Mosquito trap (MM trap) were compared in a 4?×?4 latin square study. In the years 2012 and 2013, more than seventy 24-hour trap comparisons were conducted at ten different locations in northern and southern Germany, representing urban, forest and floodplain biotopes. Results Per 24-hour trapping period, the BG trap caught the widest range of mosquito species, the highest number of individuals of the genus Culex as well as the highest number of individuals of the species Ochlerotatus cantans, Aedes cinereus/geminus, Oc. communis and Culex pipiens/torrentium. The CDC trap revealed best performance for Aedes vexans, whereas the MM trap was most efficient for mosquitoes of the genus Anopheles and the species Oc. geniculatus. The EVS trap did not catch more individuals of any genus or species compared to the other three trapping devices. The BG trap caught the highest number of individuals per trapping period in urban environments as well as in wet forest, while the CDC trap caught the highest number of individuals in the floodplain biotopes. Additionally, the BG trap was most efficient for the number of mosquito species in urban locations. Conclusion The BG trap showed a significantly better or similar performance compared to the CDC, EVS or MM trap with regard to trapping efficacy for most common mosquito species in Germany, including diversity of mosquito species and number of mosquitoes per trapping period. Thus, the BG trap is probably the best solution for general monitoring or surveillance programs of adult mosquitoes in Central Europe.

2014-01-01

270

Wash resistance and repellent properties of Africa University mosquito blankets against mosquitoes  

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Full Text Available The effect of permethrin-treated Africa University (AU mosquito blankets on susceptible female Anopheles gambiae sensu lato mosquitoes was studied under laboratory conditions at Africa University Campus in Mutare, Zimbabwe. Wash resistance (ability to retain an effective dose that kills ?80% of mosquitoes after a number of washes and repellence (ability to prevent ?80% of mosquito bites properties were studied. The AU blankets were wash resistant when 100% mortality was recorded up to 20 washes, declining to 90% after 25 washes. Untreated AU blankets did not cause any mortality on mosquitoes. However, mosquito repellence was 96%, 94%, 97.9%, 87%, 85% and 80.7% for treated AU blankets washed 0, 5, 10, 15, 20 and 25 times, respectively. Mosquito repellence was consistently above 80% from 0-25 washes. In conclusion, AU blankets washed 25 times were effective in repelling and killing An. gambiae sl mosquitoes under laboratory conditions.

M. Zimba

2013-04-01

271

Wash resistance and repellent properties of Africa University mosquito blankets against mosquitoes  

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The effect of permethrin-treated Africa University (AU) mosquito blankets on susceptible female Anopheles gambiae sensu lato mosquitoes was studied under laboratory conditions at Africa University Campus in Mutare, Zimbabwe. Wash resistance (ability to retain an effective dose that kills ?80% of mosquitoes after a number of washes) and repellence (ability to prevent ?80% of mosquito bites) properties were studied. The AU blankets were wash resistant when 100% mortality was reco...

Lukwa, N.; Makuwaza, A.; Chiwade, T.; Mutambu, S. L.; Zimba, M.; Munosiyei, P.

2013-01-01

272

Organic enrichment of breeding sources for sustained productivity of mosquitoes (Diptera: Culicidae).  

Science.gov (United States)

Alfalfa pellets and chicken lay mash were used to obtain polluted water for continuous and sustained oviposition by Culex mosquitoes. Water in fiberglass tubs enriched with 0.1 and 0.25 percent (w/v) of either material received heavy oviposition by gravid mosquitoes. The higher level of enrichment resulted in greater oviposition than lower concentrations which in turn received significantly more oviposition than the controls with no enrichment. Oviposition continued in the enriched tubs for more than 43 days where Culex quinquefasciatus and Culex stigmatosoma constituted a major proportion of the eggs laid while Culex tarsalis, as expected, oviposited at much lower rates than the other two species. Supplemental enrichment of mosquito breeding sources with organic material can thus provide uniform and sustained availability of some mosquito larvae for the evaluation of persistent control agents and other related studies. PMID:9221736

Rodcharoen, J; Mulla, M S; Chaney, J D

1997-06-01

273

New Nebraska mosquito distribution records.  

Science.gov (United States)

Larval collections in Nebraska during 2000 established 2 new state distribution records for Ochlerotatus epactius and Anopheles perplexens and confirmed the presence of Culiseta melanura, bringing the total number of mosquito species reported from Nebraska to 50. Fifteen new county records for 10 species are noted, including the 1st report of Aedes albopictus from Lancaster County, marking its westernmost collection in Nebraska to date. PMID:11804465

Moore, J P

2001-12-01

274

Impact of slow-release Bacillus sphaericus granules on mosquito populations followed in a tropical urban environment.  

Science.gov (United States)

A floating, slow-release, granular formulation of Bacillus sphaericus (Neide) was used to control mosquito larvae in two suburban areas of two tropical cities: Ouagadougou and Bobo-Dioulasso, Burkina Faso. A circular area of 2 km2, diameter 1,600 m, was treated in each city using a similar, smaller area 1 km away as an untreated control. Mosquito captures were made in houses in four concentric circles, from the periphery to the center; each circle was 50 m in width. Mosquitoes were captured in CDC light traps or from human landings. More than 95% of the mosquitoes were Culex quinquefasciatus (Say) (Diptera: Culicidae). The human landing catches provided twice as many mosquitoes as did the CDC traps/night/house. The treatments resulted in important reductions relative to the control area and to preintervention captures. The reduction was more prominent in the inner circle (up to 90%) than in the outer circle (50-70%), presumably because of the impact of immigrating mosquitoes from nontreated breeding sites around the intervention area. This effect was more pronounced for light trap catches than from human landings. The impact of treatment was also measured as the mean ratio of mosquito density in the two outer circles to that of the two inner circles. This ratio was approximately 1:1 before the intervention and reached 1:0.43 during the intervention. This comparison does not depend on the assumption that, in the absence of intervention, the mosquito population development in the two areas would have been identical, but does depend on the homogeneity of the intervention area. The study showed that it is possible to organize mosquito control in a tropical, urban environment by forming and rapidly training teams of young people to carry out the mosquito control mostly using a biopesticide that can be applied without any tools except an iron bar to lift lids on some cesspits. PMID:19198519

Skovmand, Ole; Ouedraogo, Thierry D A; Sanogo, Edith; Samuelsen, Helle; Toé, Lea P; Baldet, Thierry

2009-01-01

275

Relationships between anopheline mosquitoes and topography in West Timor and Java, Indonesia  

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Abstract Background Malaria is a serious health issue in Indonesia. Mosquito control is one aspect of an integrated malaria management programme. To focus resources on priority areas, information is needed about the vectors and their habitats. This research aimed to identify the relationship between anopheline mosquitoes and topography in West Timor and Java. Methods Study areas were selected in three topographic types in West Timor and Java. These were: coastal...

Ndoen Ermi; Wild Clyde; Dale Pat; Sipe Neil; Dale Mike

2010-01-01

276

Evaluation of low density polyethylene and nylon for delivery of synthetic mosquito attractants  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Synthetic odour baits present an unexploited potential for sampling, surveillance and control of malaria and other mosquito vectors. However, application of such baits is impeded by the unavailability of robust odour delivery devices that perform reliably under field conditions. In the present study the suitability of low density polyethylene (LDPE) and nylon strips for dispensing synthetic attractants of host-seeking Anopheles gambiae mosquitoes ...

Mukabana Wolfgang R; Mweresa Collins K; Omusula Philemon; Orindi Benedict O; Smallegange Renate C; Ja, Loon Joop; Takken Willem

2012-01-01

277

The use of transcriptional profiles to predict adult mosquito age under field conditions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Age is a critical determinant of an adult female mosquito's ability to transmit a range of human pathogens. Despite its central importance, relatively few methods exist with which to accurately determine chronological age of field-caught mosquitoes. This fact is a major constraint on our ability to fully understand the relative importance of vector longevity to disease transmission in different ecological contexts. It also limits our ability to evaluate novel disease control strategies that s...

Cook, Peter E.; Hugo, Leon E.; Iturbe-ormaetxe, In?aki; Williams, Craig R.; Chenoweth, Stephen F.; Ritchie, Scott A.; Ryan, Peter A.; Kay, Brian H.; Blows, Mark W.; O Neill, Scott L.

2006-01-01

278

Evaluation of low density polyethylene and nylon for delivery of synthetic mosquito attractants.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

BACKGROUND: Synthetic odour baits present an unexploited potential for sampling, surveillance and control of malaria and other mosquito vectors. However, application of such baits is impeded by the unavailability of robust odour delivery devices that perform reliably under field conditions. In the present study the suitability of low density polyethylene (LDPE) and nylon strips for dispensing synthetic attractants of host-seeking Anopheles gambiae mosquitoes was evaluated. METHODS: Baseline e...

Mukabana, W. R.; Mweresa, C. K.; Omusula, P.; Orindi, B. O.; Smallegange, R. C.; Loon, J. J. A.; Takken, W.

2012-01-01

279

Transgenic mosquitoes and the fight against malaria: managing technology push in a turbulent GMO world  

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Genetic modification (GM) of mosquitoes (which renders them genetically modified organisms, GMOs) offers opportunities for controlling malaria. Transgenic strains of mosquitoes have been developed and evaluation of these to 1) replace or suppress wild vector populations and 2) reduce transmission and deliver public health gains are an imminent prospect. The transition of this approach from confined laboratory settings to open field trials in disease-endemic countries (DECs) is a staged proces...

2007-01-01

280

Risk Factors for Mosquito House Entry in the Lao PDR  

Science.gov (United States)

Background Construction of the Nam Theun 2 hydroelectric project and flooding of a 450 km2 area of mountain plateau in south-central Lao PDR resulted in the resettlement of 6,300 people to newly built homes. We examined whether new houses would have altered risk of house entry by mosquitoes compared with traditional homes built from poorer construction materials. Methodology/Principal Findings Surveys were carried out in the Nam Theun 2 resettlement area and a nearby traditional rice farming area in 2010. Mosquitoes were sampled in bedrooms using CDC light traps in 96 resettlement houses and 96 traditional houses and potential risk factors for mosquito house entry were recorded. Risk of mosquito house entry was more than twice as high in traditional bamboo houses compared with those newly constructed from wood (Putative Japanese Encephalitis (JE) vector incidence rate ratio (IRR)?=?2.26, 95% CI 1.38–3.70, P?=?0.001; Anopheline IRR?=?2.35, 95% CI: 1.30–4.23, P?=?0.005). Anophelines were more common in homes with cattle compared against those without (IRR?=?2.32, 95% CI: 1.29–4.17, P?=?0.005).Wood smoke from cooking fires located under the house or indoors was found to be protective against house entry by both groups of mosquito, compared with cooking in a separate room beside the house (Putative JE vector IRR?=?0.43, 95% CI: 0.26–0.73, P?=?0.002; Anopheline IRR?=?0.22, 95% CI: 0.10–0.51, P<0.001). Conclusions/Significance Construction of modern wooden homes should help reduce human-mosquito contact in the Lao PDR. Reduced mosquito contact rates could lead to reduced transmission of diseases such as JE and malaria. Cattle ownership was associated with increased anopheline house entry, so zooprophylaxis for malaria control is not recommended in this area. Whilst wood smoke was protective against putative JE vector and anopheline house entry we do not recommend indoor cooking since smoke inhalation can enhance respiratory disease.

Hiscox, Alexandra; Khammanithong, Phasouk; Kaul, Surinder; Sananikhom, Pany; Luthi, Ruedi; Brey, Paul T.; Lindsay, Steve W.

2013-01-01

 
 
 
 
281

Transmission of malaria to mosquitoes blocked by bumped kinase inhibitors.  

Science.gov (United States)

Effective control and eradication of malaria will require new tools to prevent transmission. Current antimalarial therapies targeting the asexual stage of Plasmodium do not prevent transmission of circulating gametocytes from infected humans to mosquitoes. Here, we describe a new class of transmission-blocking compounds, bumped kinase inhibitors (BKIs), which inhibit microgametocyte exflagellation. Oocyst formation and sporozoite production, necessary for transmission to mammals, were inhibited in mosquitoes fed on either BKI-1-treated human blood or mice treated with BKI-1. BKIs are hypothesized to act via inhibition of Plasmodium calcium-dependent protein kinase 4 and predicted to have little activity against mammalian kinases. Our data show that BKIs do not inhibit proliferation of mammalian cell lines and are well tolerated in mice. Used in combination with drugs active against asexual stages of Plasmodium, BKIs could prove an important tool for malaria control and eradication. PMID:22565309

Ojo, Kayode K; Pfander, Claudia; Mueller, Natascha R; Burstroem, Charlotte; Larson, Eric T; Bryan, Cassie M; Fox, Anna M W; Reid, Molly C; Johnson, Steven M; Murphy, Ryan C; Kennedy, Mark; Mann, Henning; Leibly, David J; Hewitt, Stephen N; Verlinde, Christophe L M J; Kappe, Stefan; Merritt, Ethan A; Maly, Dustin J; Billker, Oliver; Van Voorhis, Wesley C

2012-06-01

282

Gametocytes infectiousness to mosquitoes: variable selection using random forests, and zero inflated models  

CERN Document Server

Malaria control strategies aiming at reducing disease transmission intensity may impact both oocyst intensity and infection prevalence in the mosquito vector. Thus far, mathematical models failed to identify a clear relationship between Plasmodium falciparum gametocytes and their infectiousness to mosquitoes. Natural isolates of gametocytes are genetically diverse and biologically complex. Infectiousness to mosquitoes relies on multiple parameters such as density, sex-ratio, maturity, parasite genotypes and host immune factors. In this article, we investigated how density and genetic diversity of gametocytes impact on the success of transmission in the mosquito vector. We analyzed data for which the number of covariates plus attendant interactions is at least of order of the sample size, precluding usage of classical models such as general linear models. We then considered the variable importance from random forests to address the problem of selecting the most influent variables. The selected covariates were ...

Genuer, Robin; Toussile, Wilson

2011-01-01

283

Residual effectiveness of lambda-cyhalothrin harbourage sprays against foliage-resting mosquitoes in north Queensland.  

Science.gov (United States)

The residual efficacy of lambda-cyhalothrin sprayed on foliage was evaluated against various mosquito species in sections of forest in Cairns, Queensland, Australia Weekly sweep-net collections in treated and untreated areas before and after spraying showed 87-100% reductions in mosquito numbers for the first 9 wk postspray. After that period, reductions fluctuated but remained >71% up to 14 wk posttreatment. Mosquito mortality ranged from 96 to 100% in contact bioassays of treated leaves during the 14 wk study. Our results demonstrate that spraying harborage vegetation with lambda-cyhalothrin is an extremely effective strategy for the control of sylvan and peridomestic mosquito species in tropical north Queensland. PMID:24724295

Muzari, Odwell M; Adamczyk, Rebecca; Davis, Joseph; Ritchie, Scott; Devine, Gregor

2014-03-01

284

Larvicidal activity of neem oil (Azadirachta indica) formulation against mosquitoes  

Science.gov (United States)

Background Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Azadirachta indica (Meliaceae) and its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of neem-based biopesticide for the control of mosquitoes. Methods Larvicidal efficacy of an emulsified concentrate of neem oil formulation (neem oil with polyoxyethylene ether, sorbitan dioleate and epichlorohydrin) developed by BMR & Company, Pune, India, was evaluated against late 3rd and early 4th instar larvae of different genera of mosquitoes. The larvae were exposed to different concentrations (0.5–5.0 ppm) of the formulation along with untreated control. Larvicidal activity of the formulation was also evaluated in field against Anopheles, Culex, and Aedes mosquitoes. The formulation was diluted with equal volumes of water and applied @ 140 mg a.i./m2 to different mosquito breeding sites with the help of pre calibrated knapsack sprayer. Larval density was determined at pre and post application of the formulation using a standard dipper. Results Median lethal concentration (LC50) of the formulation against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti was found to be 1.6, 1.8 and 1.7 ppm respectively. LC50 values of the formulation stored at 26°C, 40°C and 45°C for 48 hours against Ae. aegypti were 1.7, 1.7, 1.8 ppm while LC90 values were 3.7, 3.7 and 3.8 ppm respectively. Further no significant difference in LC50 and LC90 values of the formulation was observed against Ae. aegypti during 18 months storage period at room temperature. An application of the formulation at the rate of 140 mg a.i./m2 in different breeding sites under natural field conditions provided 98.1% reduction of Anopheles larvae on day 1; thereafter 100% reduction was recorded up to week 1 and more than 80% reduction up to week 3, while percent reduction against Culex larvae was 95.5% on day 1, and thereafter 80% reduction was achieved up to week 3. The formulation also showed 95.1% and, 99.7% reduction of Aedes larvae on day 1 and day 2 respectively; thereafter 100% larval control was observed up to day 7. Conclusion The neem oil formulation was found effective in controlling mosquito larvae in different breeding sites under natural field conditions. As neem trees are widely distributed in India, their formulations may prove to be an effective and eco-friendly larvicide, which could be used as an alternative for malaria control.

Dua, Virendra K; Pandey, Akhilesh C; Raghavendra, Kamaraju; Gupta, Ashish; Sharma, Trilochan; Dash, Aditya P

2009-01-01

285

Larvicidal activity of neem oil (Azadirachta indica formulation against mosquitoes  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Azadirachta indica (Meliaceae and its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of neem-based biopesticide for the control of mosquitoes. Methods Larvicidal efficacy of an emulsified concentrate of neem oil formulation (neem oil with polyoxyethylene ether, sorbitan dioleate and epichlorohydrin developed by BMR & Company, Pune, India, was evaluated against late 3rd and early 4th instar larvae of different genera of mosquitoes. The larvae were exposed to different concentrations (0.5–5.0 ppm of the formulation along with untreated control. Larvicidal activity of the formulation was also evaluated in field against Anopheles, Culex, and Aedes mosquitoes. The formulation was diluted with equal volumes of water and applied @ 140 mg a.i./m2 to different mosquito breeding sites with the help of pre calibrated knapsack sprayer. Larval density was determined at pre and post application of the formulation using a standard dipper. Results Median lethal concentration (LC50 of the formulation against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti was found to be 1.6, 1.8 and 1.7 ppm respectively. LC50 values of the formulation stored at 26°C, 40°C and 45°C for 48 hours against Ae. aegypti were 1.7, 1.7, 1.8 ppm while LC90 values were 3.7, 3.7 and 3.8 ppm respectively. Further no significant difference in LC50 and LC90 values of the formulation was observed against Ae. aegypti during 18 months storage period at room temperature. An application of the formulation at the rate of 140 mg a.i./m2 in different breeding sites under natural field conditions provided 98.1% reduction of Anopheles larvae on day 1; thereafter 100% reduction was recorded up to week 1 and more than 80% reduction up to week 3, while percent reduction against Culex larvae was 95.5% on day 1, and thereafter 80% reduction was achieved up to week 3. The formulation also showed 95.1% and, 99.7% reduction of Aedes larvae on day 1 and day 2 respectively; thereafter 100% larval control was observed up to day 7. Conclusion The neem oil formulation was found effective in controlling mosquito larvae in different breeding sites under natural field conditions. As neem trees are widely distributed in India, their formulations may prove to be an effective and eco-friendly larvicide, which could be used as an alternative for malaria control.

Dua Virendra K

2009-06-01

286

Transmission of malaria to mosquitoes blocked by bumped kinase inhibitors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Effective control and eradication of malaria will require new tools to prevent transmission. Current antimalarial therapies targeting the asexual stage of Plasmodium do not prevent transmission of circulating gametocytes from infected humans to mosquitoes. Here, we describe a new class of transmission-blocking compounds, bumped kinase inhibitors (BKIs), which inhibit microgametocyte exflagellation. Oocyst formation and sporozoite production, necessary for transmission to mammals, were inhibit...

2012-01-01

287

What environmental factors are important determinants of structure, species richness, and abundance of mosquito assemblages?  

Science.gov (United States)

Despite numerous ecological studies with mosquitoes, it remains unclear what environmental factors are the most important determinants of structure, species richness, and abundance of mosquito assemblages. In the current study, we investigated relations between these characteristics of mosquito larvae assemblages and environmental factors in a large set of different habitats. Particular objectives were (1) to rank the factors regarding their explanatory power, and (2) to quantify the contribution of major sets of factors such as habitat spatial/hydrological (H), water physico-chemical (W), and aquatic vegetation characteristics (V). Variance partitioning and forward selection based on ordinations and multiple regressions were applied to the data set on 79 water-bodies in southwestern Siberia covering a wide gradient of environmental characteristics and diverse mosquito assemblages. The results showed that richness and abundance inter-correlated poorly (r2 = 0.21), and assemblage structure, richness, and abundance depended on different sets of predictors. Explanatory importance of the three sets of environmental factors differed among the three assemblage variables: H, W, and V had equal importance for assemblage structure, while richness and abundance depended on H and V more than on W. The study showed that contradiction between the aims of conservation (support biodiversity) and mosquito control (reduce mosquito abundance) can be avoided, as relevant environmental factors can be used to define habitats with high richness and low abundance (i.e., high conservation value and low nuisance and disease transmission risk) for conservation activities, and conversely for control measures. PMID:20380292

Beketov, Mikhail A; Yurchenko, Yury A; Belevich, Olga E; Liess, Matthias

2010-03-01

288

Effects of insect growth regulators on the mosquito-parasitic nematode Romanomermis iyengari.  

Science.gov (United States)

Pyriproxyfen, a juvenile hormone analogue, diflubenzuron, a chitin synthesis inhibitor, and azadirachtin, an ecdysone agonist, are three insect growth regulators (IGRs) considered as selective and effective insecticides for mosquitoes. Romanomermis iyengari (Welch) is a mosquito-parasitic mermithid that can provide biological control against many medically important mosquito species. The compatibility of these two control tactics was tested by evaluating the sublethal effects of exposure to IGR on nematode developmental stages (preparasitic, parasitic, and preparasitic + parasitic) using Culex pipiens larvae as the host. Sublethal concentrations of IGRs were 90 % emergence inhibition of host mosquito. Preparasitic exposure to pyriproxyfen, azadirachtin, and diflurbenzuron had no effect on infectivity, parasite load, sex ratio, or male size but reduced nematode female length and increased male sex ratio at one parasite/larva. When IGRs treatments were made against the parasitic and preparasitic + parasitic stages, pyriproxyfen and azadirachtin reduced R. iyengari infectivity, parasite load, and male nematode length, whereas pyriproxyfen exposure increased male sex ratio and reduced the female R. iyengari length. Thus, IGRs have significant negative impacts on different stages of mosquito mermithid that can destabilize the balance of host-parasite population interaction. Therefore, IGRs should be used with caution in mosquito habitats where these parasites have established. PMID:23180130

Suman, Devi Shankar; Brey, Christopher W; Wang, Yi; Sanad, Manar; Shamseldean, Muhammed S M; Gaugler, Randy

2013-02-01

289

Oviposition-Modifying Substances for Mosquitoes.  

Science.gov (United States)

The objectives of this research project are to study the chemistry and the biology of oviposition-modifying substances for mosquitoes, to investigate the possibility of applying them in the management of mosquito populations, and to evaluate the role of o...

Y. S. Hwang

1980-01-01

290

PMI Activity TZ-1,2: IRS and LLIN: Integration of Methods and Insecticide Mode of Actions for Control of African Malaria Vector Mosquitoes  

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Long lasting Insecticidal nets (LLINs) and indoor residual spraying (IRS) are the preferred techniques for malaria vector control in Africa, where their application has a proven contribution to the recent significant reductions in the burden of the disease. Even though both methods are commonly used together in the same households, evidence of improved malaria control due to the use of combinations as opposed to use of either method alone has been minimal and inconclusive.To measure the mode ...

2012-01-01

291

Effect of rice husbandry on mosquito breeding at Mwea Rice Irrigation Scheme with reference to biocontrol strategies.  

Science.gov (United States)

A study was carried out at Mwea Rice Irrigation Scheme, Kenya, to assess the impact of rice husbandry on mosquito breeding and identify indigenous biocontrol agents with potential for controlling mosquito breeding in the scheme. The study established a close relationship between the schedule of the farming practices (particularly the flooding phase) and mosquito breeding. Two groups of agents, entomopathogenic bacteria (Bacillus thuringiensis var. israelensis) and larvivorous fish, were identified. Laboratory evaluation of the agents produced encouraging results. The bacterial isolates showed broad-spectrum larvicidal potency against Anopheles, Culex and Aedes mosquito larvae and 2 of the fish species, Tilapia zilli and Oreochromis niloticus, demonstrated a strong predation for a mosquito larval diet. To facilitate their use in effective biocontrol strategies, the agents would require further evaluation under field conditions. PMID:8096871

Asimeng, E J; Mutinga, M J

1993-03-01

292

A systematic review of mosquito coils and passive emanators: defining recommendations for spatial repellency testing methodologies  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propose scientific consensus on terminologies and methodologies used for evaluation of product formats that could contain spatial chemical actives, including indoor residual spraying (IRS, long lasting insecticide treated nets (LLINs and insecticide treated materials (ITMs. PubMed, (National Centre for Biotechnology Information (NCBI, U.S. National Library of Medicine, NIH, MEDLINE, LILAC, Cochrane library, IBECS and Armed Forces Pest Management Board Literature Retrieval System search engines were used to identify studies of pyrethroid based coils and emanators with key-words “Mosquito coils” “Mosquito emanators” and “Spatial repellents”. It was concluded that there is need to improve statistical reporting of studies, and reach consensus in the methodologies and terminologies used through standardized testing guidelines. Despite differing evaluation methodologies, data showed that coils and emanators induce mortality, deterrence, repellency as well as reduce the ability of mosquitoes to feed on humans. Available data on efficacy outdoors, dose–response relationships and effective distance of coils and emanators is inadequate for developing a target product profile (TPP, which will be required for such chemicals before optimized implementation can occur for maximum benefits in disease control.

Ogoma Sheila B

2012-12-01

293

A systematic review of mosquito coils and passive emanators: defining recommendations for spatial repellency testing methodologies.  

Science.gov (United States)

Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propose scientific consensus on terminologies and methodologies used for evaluation of product formats that could contain spatial chemical actives, including indoor residual spraying (IRS), long lasting insecticide treated nets (LLINs) and insecticide treated materials (ITMs). PubMed, (National Centre for Biotechnology Information (NCBI), U.S. National Library of Medicine, NIH), MEDLINE, LILAC, Cochrane library, IBECS and Armed Forces Pest Management Board Literature Retrieval System search engines were used to identify studies of pyrethroid based coils and emanators with key-words "Mosquito coils" "Mosquito emanators" and "Spatial repellents". It was concluded that there is need to improve statistical reporting of studies, and reach consensus in the methodologies and terminologies used through standardized testing guidelines. Despite differing evaluation methodologies, data showed that coils and emanators induce mortality, deterrence, repellency as well as reduce the ability of mosquitoes to feed on humans. Available data on efficacy outdoors, dose-response relationships and effective distance of coils and emanators is inadequate for developing a target product profile (TPP), which will be required for such chemicals before optimized implementation can occur for maximum benefits in disease control. PMID:23216844

Ogoma, Sheila B; Moore, Sarah J; Maia, Marta F

2012-01-01

294

Evaluation of low density polyethylene and nylon for delivery of synthetic mosquito attractants  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Synthetic odour baits present an unexploited potential for sampling, surveillance and control of malaria and other mosquito vectors. However, application of such baits is impeded by the unavailability of robust odour delivery devices that perform reliably under field conditions. In the present study the suitability of low density polyethylene (LDPE and nylon strips for dispensing synthetic attractants of host-seeking Anopheles gambiae mosquitoes was evaluated. Methods Baseline experiments assessed the numbers of An. gambiae mosquitoes caught in response to low density polyethylene (LDPE sachets filled with attractants, attractant-treated nylon strips, control LDPE sachets, and control nylon strips placed in separate MM-X traps. Residual attraction of An. gambiae to attractant-treated nylon strips was determined subsequently. The effects of sheet thickness and surface area on numbers of mosquitoes caught in MM-X traps containing the synthetic kairomone blend dispensed from LDPE sachets and nylon strips were also evaluated. Various treatments were tested through randomized 4?×?4 Latin Square experimental designs under semi-field conditions in western Kenya. Results Attractant-treated nylon strips collected 5.6 times more An. gambiae mosquitoes than LDPE sachets filled with the same attractants. The attractant-impregnated nylon strips were consistently more attractive (76.95%; n?=?9,120 than sachets containing the same attractants (18.59%; n?=?2,203, control nylon strips (2.17%; n?=?257 and control LDPE sachets (2.29%; n?=?271 up to 40?days post-treatment (P? Conclusion Nylon strips continuously dispense synthetic mosquito attractants several weeks post treatment. This, added to the superior performance of nylon strips relative to LDPE material in dispensing synthetic mosquito attractants, opens up the opportunity for showcasing the effectiveness of odour-baited devices for sampling, surveillance and control of disease vectors.

Mukabana Wolfgang R

2012-09-01

295

Can Wolbachia be used to control malaria?  

Directory of Open Access Journals (Sweden)

Full Text Available Malaria is a mosquito-borne infectious disease caused by Plasmodium parasites transmitted by the infectious bite of Anopheles mosquitoes. Vector control of malaria has predominantly focused on targeting the adult mosquito through insecticides and bed nets. However, current vector control methods are often not sustainable for long periods so alternative methods are needed. A novel biocontrol approach for mosquito-borne diseases has recently been proposed, it uses maternally inherited endosymbiotic Wolbachia bacteria transinfected into mosquitoes in order to interfere with pathogen transmission. Transinfected Wolbachia strains in Aedes aegypti mosquitoes, the primary vector of dengue fever, directly inhibit pathogen replication, including Plasmodium gallinaceum, and also affect mosquito reproduction to allow Wolbachia to spread through mosquito populations. In addition, transient Wolbachia infections in Anopheles gambiae significantly reduce Plasmodium levels. Here we review the prospects of using a Wolbachia-based approach to reduce human malaria transmission through transinfection of Anopheles mosquitoes.

Thomas Walker

2011-08-01

296

Can Wolbachia be used to control malaria?  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Malaria is a mosquito-borne infectious disease caused by Plasmodium parasites transmitted by the infectious bite of Anopheles mosquitoes. Vector control of malaria has predominantly focused on targeting the adult mosquito through insecticides and bed nets. However, current vector control methods are [...] often not sustainable for long periods so alternative methods are needed. A novel biocontrol approach for mosquito-borne diseases has recently been proposed, it uses maternally inherited endosymbiotic Wolbachia bacteria transinfected into mosquitoes in order to interfere with pathogen transmission. Transinfected Wolbachia strains in Aedes aegypti mosquitoes, the primary vector of dengue fever, directly inhibit pathogen replication, including Plasmodium gallinaceum, and also affect mosquito reproduction to allow Wolbachia to spread through mosquito populations. In addition, transient Wolbachia infections in Anopheles gambiae significantly reduce Plasmodium levels. Here we review the prospects of using a Wolbachia-based approach to reduce human malaria transmission through transinfection of Anopheles mosquitoes.

Walker, Thomas; Moreira, Luciano Andrade.

297

Reduction of mosquito biting-pressure: spatial repellents or mosquito traps? A field comparison of seven commercially available products in Israel.  

Science.gov (United States)

The present study assessed the personal protection efficiency of seven commercially available mosquito control devices (MCD) under field conditions in Israel. Trials were performed in a high biting-pressure area inhabited by large populations of mosquito and biting midge species, using human volunteers as bait in landing catch experiments. Results show that under minimal air-movement, three spatial repellent based products (ThermaCELL(®) Patio Lantern, OFF!(®) PowerPad lamp, and Terminix(®) ALLCLEAR Tabletop Mosquito Repeller) significantly reduced the biting-pressure (t-test - P<0.01) when positioned at short distances from a volunteer (3, 7.5, and 10ft.), with the ThermaCELL unit being most effective (96.1, 89.9, and 76.66% reduction, respectively). No significant differences were seen between the three aforementioned devices at distances of 3 and 7.5ft., while at a distance of 10ft., only the ThermaCELL patio lantern repelled significantly more mosquitoes then the Terminix ALLCLEAR Tabletop Mosquito Repeller (t-test, P<0.05). In contrast, mosquito traps using attracting cues to bait mosquitoes (Dynatrap(®), Vortex(®) Electronic Insect Trap, Blue Rhino(®) SV3100) either significantly increased or had no effect on the biting-pressure at short distances compared with the unprotected control. Trials conducted over large areas showed that only the Blue Rhino trap was able to significantly reduce the biting-pressure (40.1% reduction), but this was only when operating four units at the corners of an intermediate sized area. PMID:23545129

Revay, Edita E; Kline, Daniel L; Xue, Rui-De; Qualls, Whitney A; Bernier, Ulrich R; Kravchenko, Vasiliy D; Ghattas, Nina; Pstygo, Irina; Müller, Günter C

2013-07-01

298

Human to Mosquito Transmission of Dengue Viruses  

Science.gov (United States)

The successful transmission of dengue virus from a human host to a mosquito vector requires a complex set of factors to align. It is becoming increasingly important to improve our understanding of the parameters that shape the human to mosquito component of the transmission cycle so that vaccines and therapeutic antivirals can be fully evaluated and epidemiological models refined. Here we describe these factors, and discuss the biological and environmental impacts and demographic changes that are influencing these dynamics. Specifically, we examine features of the human infection required for the mosquito to acquire the virus via natural blood feeding, as well as the biological and environmental factors that influence a mosquito’s susceptibility to infection, up to the point that they are capable of transmitting the virus to a new host.

Carrington, Lauren B.; Simmons, Cameron P.

2014-01-01

299

Modeling habitat and environmental factors affecting mosquito abundance in Chesapeake, Virginia  

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The models I present in this dissertation were designed to enable mosquito control agencies in the mid-Atlantic region that oversee large jurisdictions to rapidly track the spatial and temporal distributions of mosquito species, especially those species known to be vectors of eastern equine encephalitis and West Nile virus. I was able to keep these models streamlined, user-friendly, and not cost-prohibitive using empirically based digital data to analyze mosquito-abundance patterns in real landscapes. This research is presented in three major chapters: (II) a series of semi-static habitat suitability indices (HSI) grounded on well-documented associations between mosquito abundance and environmental variables, (III) a dynamic model for predicting both spatial and temporal mosquito abundance based on a topographic soil moisture index and recent weather patterns, and (IV) a set of protocols laid out to aid mosquito control agencies for the use of these models. The HSIs (Chapter II) were based on relationships of mosquitoes to digital surrogates of soil moisture and vegetation characteristics. These models grouped mosquitoes species derived from similarities in habitat requirements, life-cycle type, and vector competence. Quantification of relationships was determined using multiple linear regression models. As in Chapter II, relationships between mosquito abundance and environmental factors in Chapter III were quantified using regression models. However, because this model was, in part, a function of changes in weather patterns, it enables the prediction of both 'where' and 'when' mosquito outbreaks are likely to occur. This model is distinctive among similar studies in the literature because of my use of NOAA's NEXRAD Doppler radar (3-hr precipitation accumulation data) to quantify the spatial and temporal distributions in precipitation accumulation. \\ Chapter IV is unique among the chapters in this dissertation because in lieu of presenting new research, it summarizes the preprocessing steps and analyses used in the HSIs and the dynamic, weather-based, model generated in Chapters II and III. The purpose of this chapter is to provide the reader and potential users with the necessary protocols for modeling the spatial and temporal abundances and distributions of mosquitoes, with emphasis on Culiseta melanura, in a real-world landscape of the mid-Atlantic region. This chapter also provides enhancements that could easily be incorporated into an environmentally sensitive integrated pest management program.

Bellows, Alan Scott

300

Transcriptome of the adult female malaria mosquito vector Anopheles albimanus  

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Full Text Available Abstract Background Human Malaria is transmitted by mosquitoes of the genus Anopheles. Transmission is a complex phenomenon involving biological and environmental factors of humans, parasites and mosquitoes. Among more than 500 anopheline species, only a few species from different branches of the mosquito evolutionary tree transmit malaria, suggesting that their vectorial capacity has evolved independently. Anopheles albimanus (subgenus Nyssorhynchus is an important malaria vector in the Americas. The divergence time between Anopheles gambiae, the main malaria vector in Africa, and the Neotropical vectors has been estimated to be 100 My. To better understand the biological basis of malaria transmission and to develop novel and effective means of vector control, there is a need to explore the mosquito biology beyond the An. gambiae complex. Results We sequenced the transcriptome of the An. albimanus adult female. By combining Sanger, 454 and Illumina sequences from cDNA libraries derived from the midgut, cuticular fat body, dorsal vessel, salivary gland and whole body, we generated a single, high-quality assembly containing 16,669 transcripts, 92% of which mapped to the An. darlingi genome and covered 90% of the core eukaryotic genome. Bidirectional comparisons between the An. gambiae, An. darlingi and An. albimanus predicted proteomes allowed the identification of 3,772 putative orthologs. More than half of the transcripts had a match to proteins in other insect vectors and had an InterPro annotation. We identified several protein families that may be relevant to the study of Plasmodium-mosquito interaction. An open source transcript annotation browser called GDAV (Genome-Delinked Annotation Viewer was developed to facilitate public access to the data generated by this and future transcriptome projects. Conclusions We have explored the adult female transcriptome of one important New World malaria vector, An. albimanus. We identified protein-coding transcripts involved in biological processes that may be relevant to the Plasmodium lifecycle and can serve as the starting point for searching targets for novel control strategies. Our data increase the available genomic information regarding An. albimanus several hundred-fold, and will facilitate molecular research in medical entomology, evolutionary biology, genomics and proteomics of anopheline mosquito vectors. The data reported in this manuscript is accessible to the community via the VectorBase website (http://www.vectorbase.org/Other/AdditionalOrganisms/.

Martínez-Barnetche Jesús

2012-05-01

 
 
 
 
301

Elevation of dopamine level reduces host-seeking activity in the adult female mosquito Aedes albopictus  

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Full Text Available Abstract Background Mosquito-borne viruses are transmitted to human hosts via blood-feeding behavior of female mosquitoes. Female mosquitoes seek a host to take blood meals (host-seeking behavior. In order to prevent virus infections, it is important to understand how they modulate host-seeking behavior. Dopamine (DA in the central nervous system acts as a neuromediator that regulates a variety of behaviors in insects. In female mosquitoes, host-seeking behavior increases when DA levels in the head decline after emergence. However, it remains unclear whether DA directly modulates host-seeking behavior in female mosquitoes. The aim of this study was to examine whether changes in DA levels in the head affects host-seeking activity in the adult female mosquito Aedes albopictus (Ae. albopictus. Findings We compared host-seeking behavior in one group of emerging female adults treated with l-?-3,4-dihydroxyphenylalanine (l-DOPA, the precursor of DA, (l-DOPA group, with that in an untreated control (control group after confirming elevation of head DA in l-DOPA group by using high-performance liquid chromatography. The content of head DA in l-DOPA group significantly remained higher than that in controls on all days examined. The host-seeking activity in the control group showed a gradual increase over the 6-day experimental period. In contrast, there was no such increase in the host-seeking activity in the l-DOPA group. Therefore, the host-seeking activity of l-DOPA group was significantly lower than that of the controls between day 3 and 6 post-emergence. Conclusion Our results indicate that elevation of DA level reduces host-seeking activity in adult female mosquito Ae. albopictus.

Fukumitsu Yuki

2012-05-01

302

Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control  

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Abstract Background Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM) that may include the sterile insect technique (SIT). To support the planning and implementation of future AW-IPM activ...

2009-01-01

303

Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background - Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM) that may include the sterile insect technique (SIT). To support the planning and implementation of future AW-IPM activities, larval surveys were carrie...

Ageep, T. B.; Cox, J.; Hassan, M. M.; Knols, B. G. J.; Benedict, M. Q.; Malcolm, C. A.; Babiker, A.; El Sayed, B. B.

2009-01-01

304

Transcription profiling of resistance to Bti toxins in the mosquito Aedes aegypti using next-generation sequencing.  

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The control of mosquitoes transmitting infectious diseases relies mainly on the use of chemical insecticides. However, resistance to most chemical insecticides threatens mosquito control programs. In this context, the spraying of toxins produced by the bacteria Bacillus thuringiensis subsp. israelensis (Bti) in larval habitats represents an alternative to chemical insecticides and is now widely used for mosquito control. Recent studies suggest that resistance of mosquitoes to Bti toxin may occur locally but mechanisms have not been characterized so far. In the present study, we investigated gene transcription level variations associated with Bti toxin resistance in the mosquito Aedes aegypti using a next-generation sequencing approach. More than 6 million short cDNA tags were sequenced from larvae of two strains sharing the same genetic background: a Bti toxins-resistant strain and a susceptible strain. These cDNA tags were mapped with a high coverage (308 reads per position in average) to more than 6000 genes of Ae. aegypti genome and used to quantify and compare the transcription level of these genes between the two mosquito strains. Among them, 86 genes were significantly differentially transcribed more than 4-fold in the Bti toxins resistant strain comparatively to the susceptible strain. These included gene families previously associated with Bti toxins resistance such as serine proteases, alkaline phosphatase and alpha-amylase. These results are discussed in regards of potential Bti toxins resistance mechanisms in mosquitoes. PMID:22115744

Paris, Margot; Melodelima, Christelle; Coissac, Eric; Tetreau, Guillaume; Reynaud, Stephane; David, Jean-Philippe; Despres, Laurence

2012-02-01

305

BIOACTIVIDAD DE ACEITES ESENCIALES DE Minthostachys mollis CONTRA MOSQUITOS  

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Full Text Available El control químico de vectores es una herramienta principal de prevención de enfermedades transmitidas por mosquitos. Los aceites esenciales (AE de plantas pueden ser una alternativa a los compuestos sintéticos. Se extrajeron por arrastre con vapor AE de Minthostachys mollis y se evaluó su actividad insecticida contra larvas, pupas y adultos de mosquitos, según protocolos estándar de la Organización Mundial de la Salud. Se evaluaron concentraciones entre 10 y 160 ppm del AE y se registró la mortalidad a las 1, 2, 3 y 24 h de exposición. La dosis de 160 ppm mostró una clara actividad insecticida en larvas y adultos, pero no en pupas. Los resultados sugieren que este aceite puede tener potencial como insecticida y merita mayores estudios.

Julio A. Zygadlo

2007-01-01

306

Competition for amino acids between Wolbachia and the mosquito host, Aedes aegypti.  

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The endosymbiont Wolbachia represents a promising method of dengue control, as it reduces the ability of the primary vector, the mosquito Aedes aegypti, to transmit viruses. When mosquitoes infected with the virulent Wolbachia strain wMelPop are fed non-human blood, there is a drastic reduction in mosquito fecundity and egg viability. Wolbachia has a reduced genome and is clearly dependent on its host for a wide range of nutritional needs. The fitness defects seen in wMelPop-infected A. aegypti could be explained by competition between the mosquito and the symbiont for essential blood meal nutrients, the profiles of which are suboptimal in non-human blood. Here, we examine cholesterol and amino acids as candidate molecules for competition, as they have critical roles in egg structural development and are known to vary between blood sources. We found that Wolbachia infection reduces total cholesterol levels in mosquitoes by 15-25%. We then showed that cholesterol supplementation of a rat blood meal did not improve fecundity or egg viability deficits. Conversely, amino acid supplementation of sucrose before and after a sheep blood meal led to statistically significant increases in fecundity of approximately 15-20 eggs per female and egg viability of 30-40%. This mosquito system provides the first empirical evidence of competition between Wolbachia and a host over amino acids and may suggest a general feature of Wolbachia-insect associations. These competitive processes could affect many aspects of host physiology and potentially mosquito fitness, a key concern for Wolbachia-based mosquito biocontrol. PMID:24337107

Caragata, Eric P; Rancès, Edwige; O'Neill, Scott L; McGraw, Elizabeth A

2014-01-01

307

Fauna and Monthly Activity of Anopheles Mosquitoes in Mahshahr District, Khuzestan Province. 2013  

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Full Text Available Abstract Background and objective: Anopheles mosquitoes are the sole biologic vectors of malaria. Research on the anophelinaemosquitoesfauna and monthly activity is important in some aspects such as, in vector control.In this study, species composition and monthly activity of anopheles mosquitoes inMahshahr district has been studied. Materials and methods: Larvae and adult mosquitoes were captured in a descriptive study from selected villages. Adults were captured using total catch and hand catch methods, also larvae were captured by Ladle handling method. Larvae and adults were identified microscopically using illustrated keys for Iranian mosquitoes. Results: Totally 1746 larvae and 1167 adults of Anopheles mosquitoes were captured. Four species were identified as the Anopheles fauna in five villages consisting of Anophelesstephensi (70.55%, An. pulcherrimus (1.16%, An. dthali(5.60%, An. superpictus(22.69%.The peak of activity of Anopheles larvaeis in June and September and its monthly activity is in April to January. Conclusion: Anophelesstephensiwhich is main malaria vector in different parts of theworld and Iran, having high potential fortransmission and possibility of establishing a transmission cycle with low abundance is the characteristics ofthis species. Specific studies such as determination of biting and resting habits and host preference of adult mosquitoes inthis area is recommended

Reza Farhadinejad

2013-10-01

308

Diagnostic methods for detection & isolation of dengue viruses from vector mosquitoes.  

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Dengue is a deadly mosquito-borne infection warranting urgent attention for its containment particularly in the tropical and subtropical countries. In the absence of a vaccine or any specific drug for its treatment, an early diagnosis is considered indispensable to prevent any casualty. Detection of viruses in human sera particularly in endemic areas is cumbersome, difficult and also not desirable. Therefore, as an alternative approach, detection of the dengue virus antigen in mosquitoes has provided a reliable tool to (i) comprehend the types of viruses circulating in nature; and (ii) help in designing vector-specific control strategies. A mélange of diagnostic techniques are currently available with some advantages or disadvantages. Traditionally, cell cultures and suckling mice have been employed for virus isolations. While the virus isolation method in baby mice is time consuming, slow and expensive, the mosquito cell cultures offer a good degree of specificity. Mosquito inoculation techniques have been reported for detection and propagation of flaviviruses. Though this technique is sensitive for routine virological confirmation of dengue fever, it requires large number of infected mosquitoes, besides being time consuming. Insect bioassays (Toxo-IFA) are generally cumbersome requiring special facilities and are not suitable for large-scale epidemiological surveillance. ELISA has been shown to be a rapid and sensitive alternative to insect bioassays for monitoring arboviruses in wild populations. Reverse transcriptase polymerase chain reaction (RT-PCR) is a recent molecular diagnostic technology used for detecting virus infections in mosquitoes, which gives rapid results but is expensive and prone to contamination. This review describes the development of various techniques involved in detection and isolation of dengue viruses in mosquitoes. Definite diagnosis of the impending dengue epidemic can be made using ELISA for virological surveillance system on dengue virus antigen in the mosquito vectors. Therefore, ELISA offers a potential tool and a convenient system for quickly screening large number of samples up to the serotype level which can be employed effectively and efficiently for large scale dengue surveillance programmes on wild caught mosquito vectors. ELISA positive samples can be screened further by Toxo-IFA system for virus isolation. On the other hand, techniques like mosquitoes cell culture, mosquito inoculation (Toxo-IFA) and RT-PCR techniques can be employed for dengue virus amplification. PMID:16873905

Philip Samuel, P; Tyagi, B K

2006-05-01

309

Control of pyrethroid and DDT-resistant Anopheles gambiae by application of indoor residual spraying or mosquito nets treated with a long-lasting organophosphate insecticide, chlorpyrifos-methyl  

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Full Text Available Abstract Background Scaling up of long-lasting insecticidal nets (LLINs and indoor residual spraying (IRS with support from the Global Fund and President's Malaria Initiative is providing increased opportunities for malaria control in Africa. The most cost-effective and longest-lasting residual insecticide DDT is also the most environmentally persistent. Alternative residual insecticides exist, but are too short-lived or too expensive to sustain. Dow Agrosciences have developed a microencapsulated formulation (CS of the organophosphate chlorpyrifos methyl as a cost-effective, long-lasting alternative to DDT. Methods Chlorpyrifos methyl CS was tested as an IRS or ITN treatment in experimental huts in an area of Benin where Anopheles gambiae and Culex quinquefasiactus are resistant to pyrethroids, but susceptible to organophosphates. Efficacy and residual activity was compared to that of DDT and the pyrethroid lambdacyalothrin. Results IRS with chlorpyrifos methyl killed 95% of An. gambiae that entered the hut as compared to 31% with lambdacyhalothrin and 50% with DDT. Control of Cx. quinquefasciatus showed a similar trend; although the level of mortality with chlorpyrifos methyl was lower (66% it was still much higher than for DDT (14% or pyrethroid (15% treatments. Nets impregnated with lambdacyhalothrin were compromized by resistance, killing only 30% of An. gambiae and 8% of Cx. quinquefasciatus. Nets impregnated with chlorpyrifos methyl killed more (45% of An gambiae and 15% of Cx. quinquefasciatus, but its activity on netting was of short duration. Contact bioassays on the sprayed cement-sand walls over the nine months of monitoring showed no loss of activity of chlorpyrifos methyl, whereas lambdacyhalothrin and DDT lost activity within a few months of spraying. Conclusion As an IRS treatment against pyrethroid resistant mosquitoes chlorpyrifos methyl CS outperformed DDT and lambdacyhalothrin. In IRS campaigns, chlorpyrifos methyl CS should show higher, more-sustained levels of malaria transmission control than conventional formulations of DDT or pyrethroids. The remarkable residual activity indicates that cost-effective alternatives to DDT are feasible through modern formulation technology.

Chabi Joseph

2010-02-01

310

Historical applications of induced sterilisation in field populations of mosquitoes  

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Full Text Available Abstract Research on sterile mosquito technology from 1955 to the 1980s provided a substantial body of knowledge on propagation and release of sterile mosquitoes. Radiation sterilisation and chemosterilisation have been used effectively to induce dominant lethality and thereby sterilise important mosquito vectors in the laboratory. Experimental releases of chemosterilised males provided complete control of Anopheles albimanus in a small breeding population (14-15 sq km in El Salvador. Releases of radiation sterilised males failed to control either Aedes aegypti or Anopheles quadrimaculatus in the USA. Releases of radiation-sterilised and chemosterilised male Culex quinquefasciatus in the USA and India were successful in some instances. Development of genetic sexing systems for Anopheles and improved physical separation methods for Culex have made it possible to rear and release males almost exclusively (> 99% minimizing the release of potential vectors, the females. Factors that affected efficacy in some field programmes included reduction of competitiveness by radiation, immigration of fertilized females from outside the release zones, and inability of laboratory-bred males to perform in the wild. Despite significant progress, institutional commitments to carry the process further were generally lacking in the late 1970s and until recently. Now, with renewed interest and support for further assessment of this technology, this paper summarizes the current knowledge base, prioritizes some areas of investigation, and challenges scientists and administrators to maintain an awareness of progress, remain realistic about the interpretation of new findings, and make decisions about the sterile insect technique on the basis of informed scientific documentation. Areas recommended for priority research status include the establishment of genetic sexing mechanisms that can be transferred to other mosquito species, re-examination of radiation sterilisation, aerial release technology and mass rearing.

Knols Bart GJ

2009-11-01

311

Dengue and Chikungunya Vector Control Pocket Guide.  

Science.gov (United States)

This technical guide (TG) was written to consolidate information and procedures for surveillance and control of mosquitoes that transmit dengue and chikungunya viruses. This TG focuses on mosquitoes that transmit dengue but also makes reference to chikung...

A. Hanley C. Stoops G. Clark G. White

2012-01-01

312

Diversity and function of bacterial microbiota in the mosquito holobiont  

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Mosquitoes (Diptera: Culicidae) have been shown to host diverse bacterial communities that vary depending on the sex of the mosquito, the developmental stage, and ecological factors. Some studies have suggested a potential role of microbiota in the nutritional, developmental and reproductive biology of mosquitoes. Here, we present a review of the diversity and functions of mosquito-associated bacteria across multiple variation factors, emphasizing recent findings. Mosquito microbiota is consi...

Minard, Guillaume; Mavingui, Patrick; Moro, Claire Valiente

2013-01-01

313

The Vector Population Monitoring Tool (VPMT): High-Throughput DNA-Based Diagnostics for the Monitoring of Mosquito Vector Populations  

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Regular monitoring of mosquito vector populations is an integral component of most vector control programmes. Contemporary data on mosquito species composition, infection status, and resistance to insecticides are a prerequisite for effective intervention. For this purpose we, with funding from the Innovative Vector Control Consortium (IVCC), have developed a suite of high-throughput assays based on a single “closed-tube” platform that collectively comprise the “Vector Population Monito...

2010-01-01

314

Can mosquitoes fly in the rain?  

CERN Multimedia

Collisions with raindrops are one of many obstacles insects face during flight. In this fluid dynamics video, we present a series of high-speed films of impacts between mosquitoes and raindrops. We also present drop impacts upon insect mimics, which are unsupported styrofoam balls of the same mass as mosquitoes. High-speed videography and particle tracking during collision are employed to determine the insect position versus time. We determine the magnitude of acceleration by considering the momentum transfer and impact duration. Experiments with live mosquitoes indicate a surprising ability to quickly recover flight post-collision, despite accelerations of 30-300 gravities over durations of 1 ms.

Dickerson, Andrew; Madhavan, Nihar; Hu, David

2011-01-01

315

The discerning predator: decision rules underlying prey classification by a mosquito-eating jumping spider  

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Evarcha culicivora is an East African jumping spider that feeds indirectly on vertebrate blood by choosing blood-fed female Anopheles mosquitoes as prey. Previous studies have shown that this predator can identify its preferred prey even when restricted to using only visual cues. Here, we used lures and virtual mosquitoes to investigate the optical cues underlying this predator's prey-choice behaviour. We made lures by dissecting and then reconstructing dead mosquitoes, combining the head plu...

Nelson, Ximena J.; Jackson, Robert R.

2012-01-01

316

Quantifying the impact of mosquitoes on quality of life and enjoyment of yard and porch activities in New Jersey.  

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The recent expansion of Aedes albopictus, a day-biting mosquito, to densely inhabited areas in the northeastern Atlantic states of the USA has dramatically increased the problem that mosquitoes create for urban and suburban residents. We quantified the impact of mosquitoes on residents' quality of life within the context of a comprehensive area-wide integrated pest management program to control Ae. albopictus in two counties (Mercer and Monmouth) in New Jersey. We interviewed residents of 121 randomly selected households in both counties between October and November 2010. We asked residents about their experience with mosquitoes in their neighborhood and the importance of the ability to relax outdoors without mosquitoes compared to other neighborhood characteristics (1?=?not important, 5?=?extremely important). We rated residents' utility based on paired comparisons to known states from the EuroQol health description system. The majority (54.6%) of respondents considered mosquitoes to be a problem. Respondents reported an average of 7.1 mosquito bites in a typical week during that summer. Mosquitoes prevented 59.5% of residents from enjoying their outdoor activities at least to some extent. Residents rated the mosquito acceptability (mean ± standard deviation) during that summer on a scale of 0 (mosquito invasion) to 100 (no mosquitoes) at 56.7±28.7, and their overall utility at 0.87±0.03. This is comparable to living with up to two risk factors for diabetes (i.e., abdominal obesity, body mass index of 28 or more, reported cholesterol problems, diagnosis of hypertension, or history of cardiovascular disease) or women experiencing menstrual disorders. Respondents rated the importance of enjoying outdoor activities without mosquitoes (4.69±0.80) comparable to that of neighborhood safety (4.74±0.80) and higher than that of a clean neighborhood (4.59±0.94). In conclusion, New Jersey residents reported that mosquitoes decreased their utility by 0.13, comparable to the loss from worrisome health risk factors, underscoring the importance of controlling this problem. PMID:24603670

Halasa, Yara A; Shepard, Donald S; Fonseca, Dina M; Farajollahi, Ary; Healy, Sean; Gaugler, Randy; Bartlett-Healy, Kristen; Strickman, Daniel A; Clark, Gary G

2014-01-01

317

A rationale to design longer lasting mosquito repellents.  

Science.gov (United States)

Mosquito repellents represent a cleaner and safer alternative for population control and reduce the diseases they carry in large areas of the world. Recently, research has been focused on repellents of natural origins, both crude essential oils and their main constituents. We have observed that, although a large number of compounds can be efficiently used as mosquito repellents, their efficacy is never higher than those of commercial products DEET and Icaridin. Reasoning that probably specific and exceptionally active repellents might not exist, we focused our research on products that could provide longer protection times with respect to current commercial formulations while being used at lower concentrations. Based on the structure of menthone, a moderate natural repellent, we designed and synthesised some cyclic ketals that, because of their reduced volatility, could be effective for longer periods. In particular, a 1 % solution of one of such derivatives can still reduce mosquito bites by 90 % after 2 h, while DEET provides the same performance only for 15 min, when used at the same concentration. The approach we illustrate can be applied to other compounds and other systems and offers the additional advantage that derivatives of reduced volatility are also endowed with weaker odours. PMID:24599300

Iovinella, Immacolata; Pelosi, Paolo; Conti, Barbara

2014-05-01

318

Chromosome phylogenies of malaria mosquitoes.  

Science.gov (United States)

Malaria mosquitoes often belong to complexes of sibling species, members of which are morphologically and genetically similar to each other. However, members within these complexes can vary significantly in their ecological adaptations and abilities to transmit the malaria parasite. The high degree of genetics similarity among sibling species makes the reconstruction of phylogenetic relationships within species complexes difficult. This paper reviews studies that infer the ancestral--descendant relationships among sibling species using molecular markers and chromosomal inversions. A methodology based on analyzing breakpoints of fixed overlapping inversions is shown to be useful for rooting phylogenies in complexes of sibling species, if the chromosomal arrangements in outgroup species are known. The construction of detailed phylogenies for malaria vectors will help to identify the association of evolutionary genomic changes with the origin of human blood choice and specific ecological adaptations. PMID:23875455

Sharakhov, I V

2013-01-01

319

Laboratory evaluation of predation on mosquito larvae by Australian mangrove fish.  

Science.gov (United States)

A series of laboratory experiments compared predation rates of three native eastern Australian mangrove fish species (Psuedomugil signifer, Hyseleotris galii, Pseudogobius sp.) and the exotic Gambusia holbrooki on 2(nd) and 4(th) instar Aedes vigilax larvae, in order to determine their potential as mosquito control agents in mangrove forests. All four species preyed on significant numbers of both 2(nd) and 4(th) instar larvae. All showed a similar pattern of larval consumption, gorging on larvae in the first hour of each experiment, before reducing to a relatively constant background feeding rate. Gambusia holbrooki showed the highest larval consumption rates, but is unsuitable as a mosquito control agent due to it being an exotic pest species in Australia. Of the three native species, P. signifer showed the greatest potential as a mosquito control agent, having consumption rates comparable to G. holbrooki, and was the only species that did not show a significant reduction in larval consumption in the night experiments. PMID:24820573

Griffin, Lachlan

2014-06-01

320

Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control  

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Full Text Available Abstract Background Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM that may include the sterile insect technique (SIT. To support the planning and implementation of future AW-IPM activities, larval surveys were carried out to provide key data on spatial and seasonal dynamics of local vector populations. Methods Monthly cross-sectional larval surveys were carried out between March 2005 and May 2007 in two localities (Dongola and Merowe adjacent to the river Nile. A stratified random sampling strategy based on the use of Remote Sensing (RS, Geographical Information Systems (GIS and the Global Positioning System (GPS was used to select survey locations. Breeding sites were mapped using GPS and data on larval density and breeding site characteristics were recorded using handheld computers. Bivariate and multivariate logistic regression models were used to identify breeding site characteristics associated with increased risk of presence of larvae. Seasonal patterns in the proportion of breeding sites positive for larvae were compared visually to contemporaneous data on climate and river height. Results Of a total of 3,349 aquatic habitats sampled, 321 (9.6% contained An. arabiensis larvae. The frequency with which larvae were found varied markedly by habitat type. Although most positive sites were associated with temporary standing water around the margins of the main Nile channel, larvae were also found at brickworks and in areas of leaking pipes and canals – often far from the river. Close to the Nile channel, a distinct seasonal pattern in larval populations was evident and appeared to be linked to the rise and fall of the river level. These patterns were not evident in vector populations breeding in artificial water sources away from the river. Conclusion The GIS-based survey strategy developed in this study provides key data on the population dynamics of An. arabiensis in Northern State. Quantitative estimates of the contributions of various habitat types and their proximity to settlements provide a basis for planning a strategy for reducing malaria risk by elimination of the vector population.

Malcolm Colin A

2009-06-01

 
 
 
 
321

Natural plant sugar sources of Anopheles mosquitoes strongly impact malaria transmission potential.  

Science.gov (United States)

An improved knowledge of mosquito life history could strengthen malaria vector control efforts that primarily focus on killing mosquitoes indoors using insecticide treated nets and indoor residual spraying. Natural sugar sources, usually floral nectars of plants, are a primary energy resource for adult mosquitoes but their role in regulating the dynamics of mosquito populations is unclear. To determine how the sugar availability impacts Anopheles sergentii populations, mark-release-recapture studies were conducted in two oases in Israel with either absence or presence of the local primary sugar source, flowering Acacia raddiana trees. Compared with population estimates from the sugar-rich oasis, An. sergentii in the sugar-poor oasis showed smaller population size (37,494 vs. 85,595), lower survival rates (0.72 vs. 0.93), and prolonged gonotrophic cycles (3.33 vs. 2.36 days). The estimated number of females older than the extrinsic incubation period of malaria (10 days) in the sugar rich site was 4 times greater than in the sugar poor site. Sugar feeding detected in mosquito guts in the sugar-rich site was significantly higher (73%) than in the sugar-poor site (48%). In contrast, plant tissue feeding (poor quality sugar source) in the sugar-rich habitat was much less (0.3%) than in the sugar-poor site (30%). More important, the estimated vectorial capacity, a standard measure of malaria transmission potential, was more than 250-fold higher in the sugar-rich oasis than that in the sugar-poor site. Our results convincingly show that the availability of sugar sources in the local environment is a major determinant regulating the dynamics of mosquito populations and their vector potential, suggesting that control interventions targeting sugar-feeding mosquitoes pose a promising tactic for combating transmission of malaria parasites and other pathogens. PMID:21283732

Gu, Weidong; Müller, Günter; Schlein, Yosef; Novak, Robert J; Beier, John C

2011-01-01

322

A new larval tray and rack system for improved mosquito mass rearing.  

Science.gov (United States)

The requirement for efficient mosquito mass rearing technology has been one of the major obstacles preventing the large scale application of the Sterile Insect Technique against mosquitoes. At the Food and Agriculture Organization/International Atomic Energy Agency (FAO/ IAEA) Insect Pest Control Laboratories we developed a larval rearing unit based on the use of a stainless steel rack that operates 50 thermoformed ABS plastic trays and is expected to be able to successfully rear 140,000-175,000 Anopheles arabiensis (Patton) adult mosquitoes per rack. The mechanized rearing unit is simple to handle, maintains minimal water temperature variation and negligible water evaporation and allows normal larval development. The mosquito mass-rearing tray was designed to provide a large surface area of shallow water that would closely mimic natural breeding sites. The trays stack into a dedicated rack structure and filling and draining were easily performed. The close stacking of the trays in the rack and the possibility to tightly line up several racks makes this rearing unit a valid solution for maximal use of the space thus reducing construction, heating, and cooling costs. The low amount of labor required to operate the system also reduces labor costs that represent one of the main expenditures in any mass rearing facility operation. Preliminary experiments performed on Aedes albopictus (Skuse) also confirm the possibility of successfully extending the use of this technology to other mosquito species. Our larval rearing unit could enhance any mosquito control strategy in which large-scale releases of mosquitoes are needed to suppress or replace natural populations. PMID:22679867

Balestrino, F; Benedict, M Q; Gilles, J R L

2012-05-01

323

Avaliação de termonebulizações de propoxur contra mosquitos através de testes biológicos / Evaluation of thermonebulization of propoxur used against mosquitoes by means of biological tests  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A eficácia de termonebulização do inseticida propoxur no controle de Aedes aegypti foi avaliada através de testes realizados no Município de São José do Rio Preto, Estado de São Paulo (Brasil). Estudos comparativos monitorados por mosquitos - Culex quinquefasciatus - presos em gaiolas, indicaram que [...] o horário de aplicação do inseticida teve forte influência na mortalidade dos mosquitos, que não ultrapassou 43% quando as aplicações foram feitas entre 17 h e 17:30 h, enquanto que para as aplicações feitas após às 19 h a mortalidade média foi de 73%. Nos testes realizados à noite foi constatada uma mortalidade média não inferior a 95% nas gaiolas posicionadas em dependências com as portas e janelas abertas e naquelas onde as portas e janelas estavam fechadas observou-se uma mortalidade média não superior a 13%. Mudando-se a concentração do inseticida de 1:12 para 1:9, a mortalidade dos mosquitos não diferiu de forma significativa. Abstract in english The thermonebulization efficcacy of the insecticide propoxur used in Aedes aegypti control was evaluated by means of tests carried out in S. José do Rio Preto, S. Paulo, Brazil. Comparative studies monitored by caged mosquitoes - Culex quinquefasciatus - indicated that the applications of the insect [...] icide influenced mosquito mortality greatly, this did not exceed 43% when application were performed between 5 p.m. and 5.30 p.m., but for applications carried out after 7 p.m. the mortality mean was 73%. In tests performed at night it was observed that mean mortality was not inferior to 95% in the cages situated in presences with doors and windows open and in those in which the doors and windows were closed a mean mortality not higher than 13% was observed. Mosquito mortality did not differ significantly when the concentration of the insecticide was increased from 1:12 to 1:9.

Amir Bertoni, Gebara; Maria do Carmo Ramalho R. de, Almeida.

324

Avaliação de termonebulizações de propoxur contra mosquitos através de testes biológicos Evaluation of thermonebulization of propoxur used against mosquitoes by means of biological tests  

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Full Text Available A eficácia de termonebulização do inseticida propoxur no controle de Aedes aegypti foi avaliada através de testes realizados no Município de São José do Rio Preto, Estado de São Paulo (Brasil. Estudos comparativos monitorados por mosquitos - Culex quinquefasciatus - presos em gaiolas, indicaram que o horário de aplicação do inseticida teve forte influência na mortalidade dos mosquitos, que não ultrapassou 43% quando as aplicações foram feitas entre 17 h e 17:30 h, enquanto que para as aplicações feitas após às 19 h a mortalidade média foi de 73%. Nos testes realizados à noite foi constatada uma mortalidade média não inferior a 95% nas gaiolas posicionadas em dependências com as portas e janelas abertas e naquelas onde as portas e janelas estavam fechadas observou-se uma mortalidade média não superior a 13%. Mudando-se a concentração do inseticida de 1:12 para 1:9, a mortalidade dos mosquitos não diferiu de forma significativa.The thermonebulization efficcacy of the insecticide propoxur used in Aedes aegypti control was evaluated by means of tests carried out in S. José do Rio Preto, S. Paulo, Brazil. Comparative studies monitored by caged mosquitoes - Culex quinquefasciatus - indicated that the applications of the insecticide influenced mosquito mortality greatly, this did not exceed 43% when application were performed between 5 p.m. and 5.30 p.m., but for applications carried out after 7 p.m. the mortality mean was 73%. In tests performed at night it was observed that mean mortality was not inferior to 95% in the cages situated in presences with doors and windows open and in those in which the doors and windows were closed a mean mortality not higher than 13% was observed. Mosquito mortality did not differ significantly when the concentration of the insecticide was increased from 1:12 to 1:9.

Amir Bertoni Gebara

1988-02-01

325

Avaliação de termonebulizações de propoxur contra mosquitos através de testes biológicos / Evaluation of thermonebulization of propoxur used against mosquitoes by means of biological tests  

Scientific Electronic Library Online (English)

Full Text Available SciELO Public Health | Language: Portuguese Abstract in portuguese A eficácia de termonebulização do inseticida propoxur no controle de Aedes aegypti foi avaliada através de testes realizados no Município de São José do Rio Preto, Estado de São Paulo (Brasil). Estudos comparativos monitorados por mosquitos - Culex quinquefasciatus - presos em gaiolas, indicaram que [...] o horário de aplicação do inseticida teve forte influência na mortalidade dos mosquitos, que não ultrapassou 43% quando as aplicações foram feitas entre 17 h e 17:30 h, enquanto que para as aplicações feitas após às 19 h a mortalidade média foi de 73%. Nos testes realizados à noite foi constatada uma mortalidade média não inferior a 95% nas gaiolas posicionadas em dependências com as portas e janelas abertas e naquelas onde as portas e janelas estavam fechadas observou-se uma mortalidade média não superior a 13%. Mudando-se a concentração do inseticida de 1:12 para 1:9, a mortalidade dos mosquitos não diferiu de forma significativa. Abstract in english The thermonebulization efficcacy of the insecticide propoxur used in Aedes aegypti control was evaluated by means of tests carried out in S. José do Rio Preto, S. Paulo, Brazil. Comparative studies monitored by caged mosquitoes - Culex quinquefasciatus - indicated that the applications of the insect [...] icide influenced mosquito mortality greatly, this did not exceed 43% when application were performed between 5 p.m. and 5.30 p.m., but for applications carried out after 7 p.m. the mortality mean was 73%. In tests performed at night it was observed that mean mortality was not inferior to 95% in the cages situated in presences with doors and windows open and in those in which the doors and windows were closed a mean mortality not higher than 13% was observed. Mosquito mortality did not differ significantly when the concentration of the insecticide was increased from 1:12 to 1:9.

Amir Bertoni, Gebara; Maria do Carmo Ramalho R. de, Almeida.

326

Techniques of Mosquitoes Collecting and Laboratory Rearing  

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Full Text Available The field collecting and laboratory rearing of mosquitoes is essential for mosquito research. The mosquito specimens with perfect completeness and species richness are the foundation for extensive study on their biology, ecology, morphological taxonomy, molecular biology and insecticide resistance; however, the techniques for field colleting and laboratory rearing are still to be further improved and perfected. With many years of practice and improvement, the present paper introduces the ideal and operable tools of field collecting and laboratory rearing. Most importantly, here it summarizes in detail the collecting environment and method of mosquito larvae, pupae and adults, the techniques of the individual (with single-tube and laboratory rearing of larvae and pupae and the progeny rearing of adults, the preservation method of larval and pupal exuviae and adults, and the field transportation method of all stages of mosquitoes. These technologies and methods are of instructive significance for mosquito field investigation and the acquirement of body-completed specimens and biological-ecological information.

TANG Yao

2012-11-01

327

Señales físico químicas involucradas en la búsqueda de hospederos y en la inducción de picadura por mosquitos  

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Full Text Available Las hembras de los mosquitos vectores de enfermedades utilizan señales físicas y químicas para localizar su fuente de alimentación sanguínea en hospederos vertebrados. Los mosquitos zoofílicos responden preferentemente al CO2 y al octenol liberados en la respiración y excreciones, mientras que los mosquitos antropofílicos responden al ácido láctico y a una variedad de compuestos del sudor. Estos compuestos son modificados por microrganismos saprófitos de las glándulas sebáceas de la piel. Otros factores presentes en las viviendas contribuyen a la integración de microsistemas constituidos por olores característicos, que explican los diferentes niveles de atracción de mosquitos y la focalización de la transmisión del paludismo a una porción de casas en localidades de áreas endémicas. La identificación de estos atrayentes químicos y sus moléculas receptoras en mosquitos puede ser utilizada como complemento de nuevos métodos para la vigilancia epidemiológica, para atraer a los mosquitos a trampas de colecta o para incrementar su contacto con insecticidas usados en su control, así como en la manipulación genética para desviar las picaduras de los mosquitos hacia otros hospederos vertebrados.

Torres-Estrada José Luis

2003-01-01

328

Epidemiology of tree-hole breeding mosquitoes in the tropical rainforest of Imo State, south-east Nigeria.  

Science.gov (United States)

The study of tree-hole breeding mosquitoes was carried out in the tropical rainforest of Imo State Nigeria (two rural areas and two forest reserves in some parts of Orlu Senatorial Zone) between May-October 2002. Using standard entomological procedures, two macrohabitats (natural tree-holes and bamboo traps) and two microhabitats (leaf axils of cocoyams/pineapples and leaf axils of plantain/banana) were sampled for various mosquito species. Mosquitoes were recovered from all the various biotypes sampled. Types of mosquitoes species encountered, their relative abundance, as well as genera varied significantly during the study (p<0.05). Four genera of mosquitoes: Aedes, Culex, Anopheles and Toxorhynchites were recovered while 16 species of mosquitoes encountered include: Aedes aegypti, Ae. africanus, Ae. simpsoni, Ae. albopictus, Ae. stokesi, Ae. taylori, Ae. apicoargenteus, Culex quinquefasciatus, Cx. nebulosus, Cx. trigripes, Cx. decens, Anopheles gambiae, An. funiestus, An. coustani and Toxorhynchites viridibasis. Most of the mosquitoes showed oviposition preferences for one or more habitats. The presence of Ae. africanus, Ae. simpsoni and Ae. aegypti indicate that the study areas were at risk of yellow fever epidemic. The presence of Anopheles and Culex species ensured endemicity of malaria and filariasis, while the recovery of Ae. albopictus in this region suggests a possible outbreak of dengue fever in future if not properly controlled. PMID:17655174

Anosike, Jude C; Nwoke, Bertram E B; Okere, Anthony N; Oku, Ene E; Asor, Joe E; Emmy-Egbe, Ifeyinwa O; Adimike, Desmond A

2007-01-01

329

Riqueza de especies de mosquitos, distribución y sitios de cría en el municipio Boyeros / Wealth of mosquito species, their distribution and breeding sites in Boyeros municipality  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Introducción: la identificación de las especies de mosquitos en cada municipio en Cuba forma parte del Programa de Control de Aedes aegypti y Aedes albopictus, lo cual representa un factor importante en la aparición de eventos epidemiológicos o zoonóticos que involucren estos insectos. Objetivo: con [...] ocer la riqueza de especies de mosquitos y su distribución en el municipio Boyeros. Métodos: el trabajo se desarrolló en el municipio Boyeros, La Habana en el período 1982-2011. Las muestras de mosquitos se colectaron por los trabajadores del programa de control de Aedes aegypti y Aedes albopictus. Resultados: la riqueza de especies de mosquitos fue de 35, de estas 10 se encuentran distribuidas en todas las áreas del municipio. El área con mayor riqueza de especie fue Mulgoba seguida por Wajay, y la de menor correspondió a Boyeros. Se colectaron 8 especies en depósitos artificiales y naturales como hueco de árboles; mientras que 22 se colectaron en reservorios de aguas naturales, lagunas de oxidación, zanjas, arroyos, lagunatos y ríos. Del total de especies, 5 solo fueron colectadas en estadio adulto. Conclusiones: la emergencia y reemergencia de algunas enfermedades transmitidas por mosquitos es uno de los aspectos que más seguimiento tiene en estos momentos en el continente americano, por lo que conocer la fauna de mosquitos del municipio así como su distribución es importante. De presentarse algún brote o epidemia que involucren a estos insectos obligaría a establecer las estrategias de control, para evitar la propagación de enfermedades de transmisión vectorial. Abstract in english Introduction: the identification of mosquito species in each municipality of Cuba is part of the Aedes aegypti and Aedes albopictus control program. This is an important factor in the occurrence of epidemiological or zoonotic events involving these insects. Objective: to identify the wealth of mosqu [...] ito species and their distribution in Boyeros municipality. Methods: the study was developed in Boyeros municipality from 1982 to 2011. The mosquito samples were taken by the Aedes aegypti and Aedes albopictus control program workers. Results: the wealth of mosquito species includes 35 species of which 10 are distributed in all the areas of the municipality. The area with the largest wealth of species was Mulgoba, followed by Wajay, and the smallest one was found in Boyeros. Eight species were collected in artificial and natural reservoirs such as tree holes, whereas 22 were observed in natural water reservoirs, oxidation lagoons, ditches, streams and rivers. Of all the species, just 5 were collected in their adult stage. Conclusions: emergency and reemergence of some mosquito-borne diseases is one of the more watched aspects at this time in the American continent, thus the mosquito fauna of the municipality and its distribution is fundamental. If any outbreak or epidemic involving these insects occurs, it would be compulsory to set up control strategies to prevent the spread of vector-borne diseases.

Valdés Miró, Vivian; Reyes Arencibia, Mayra; Marquetti Fernández, María del Carmen; González Broche, Raúl.

330

Larvicidal Activity of Tephrosia vogelii Crude Extracts on Mosquito Larval Stages  

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Full Text Available The use of natural products and biological insect control methods is gaining importance because of concerns about the environment, since they are more easily biodegradable. In some parts of Uganda, organic farmers have adopted the use of Tephrosia vogelii, a shrubby, leguminous and woody plant for control of storage pests. However, the efficacy of Tephrosia vogelii crude extracts in the control of Dipteran insect larvae under field conditions has not been well tested. Their use for the control of insect vectors such as mosquitoes has not also been fully evaluated. Tephrosia vogelii plant materials were collected from two selected sites, one on a higher altitude than the other using polythene study. The material was chopped, properly labeled and air-dried in a shade for two weeks. Four solvents where used for extraction: Water, Petroleum ether, Chloroform, Methanol. The extract was dried in an oven at about 32-33°C for several days, after which it was weighed and stored in the fridge at 4°C until the time of exposing the mosquito larvae. Shoot Evening Methanol (SEM was the most effective among methanol extracts; killing an average of 4.57 mosquito larvae in 8 min while Shoot Evening Water (SEW was the most effective of water extracts killing an average of 2.57 mosquito larvae in 8 min; hence the SEM was considered to be nearly two times more efficacious than SEW on mosquito larvae, at a concentration of 25%: 10.8% or 2.3:1 SEM: SEW, respectively. Tephrosia vogelii crude extracts could potentially therefore be used to control the larval stages of mosquitoes.

2007-01-01

331

Laboratory evaluation of Bacillus thuringiensis (Vectobac WDG) against mosquito larvae, Culex pipiens and Culiseta longiareolata.  

Science.gov (United States)

Mosquitoes are vectors of many human diseases and cause environmental nuisances. Due to their Large geographical distribution and abundance, Culex pipiens and Culiseta longiareolata represent the most important mosquito species in ALgeria and many countries in the world. They are generally controlled by conventional insecticides. The high reproductive ability and development of insecticide resistance of mosquito species are Leading to a search for novel molecules. As so, Vectobac that is based on the insecticidal toxins of Bacillus thuringiensis isroelensis (Bti), may provide economical control of mosquito larvae. In this study, we tested the activity of Vectobac (WDG) at different concentrations, ranging between 2 and 30 microg/L, against the different Larval stages (L1-L4) of Cx. pipiens and C. longiareolata. Bioassays were done on newly moulted Larvae under Laboratory conditions according to the guidelines of WHO. In Cx. pipiens, mortality was scored already after 24 h, and in addition developmental effects were observed like inhibition of growth with incomplete moulting and failure of adult emergence. From a dose-response curve LC50 were calculated: 9.22 microg/L for L1 and 35.33 microg/L for L4. For C. longiareolata, the respective LC50's were 6.05 microg/L and 23 microg/L for L1 and L4. The results are discussed in relation to the susceptibility of the two mosquito species tested, lethaL doses, direct toxicity, and effects on growth and development. PMID:19226801

Boudjelida, H; Aïssaoui, L; Bouaziz, A; Smagghe, G; Soltani, N

2008-01-01

332

Olfactory responses and field attraction of mosquitoes to volatiles from Limburger cheese and human foot odor.  

Science.gov (United States)

Olfactory responses of female Aedes aegypti (Linnaeus) to various odor stimuli were studied in a dual-port olfactometer. Responses (i.e., the percent of ca. 75 available female mosquitoes in flight chamber entering each olfactometer port) were studied toward clean conditioned air (control), human foot skin emanations (collected on socks by wearing them for three days), human hand, and Limburger cheese. Mean percent response was greatest to the human hand (80.1%), followed by the human worn sock (66.1%), Limburger cheese (6.4%), and control (sock alone attracted very few mosquitoes but a synergistic response occurred to the sock + carbon dioxide baited traps for most species of mosquitoes in six genera (Aedes, Anopheles, Coquillettidia, Culex, Culiseta, and Psorophora). This synergistic effect persisted even when the socks were exposed to environmental conditions for eight consecutive days. Limburger cheese alone did not attract mosquitoes to traps compared to unbaited traps, and there appeared to be a slight repellent effect for most mosquito species when used in combination with carbon dioxide. PMID:9879074

Kline, D L

1998-12-01

333

Examining the determinants of mosquito-avoidance practices in two Kenyan cities  

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Full Text Available Abstract Background This study assesses the behavioural and socio-economic factors associated with avoiding mosquitoes and preventing malaria in urban environments in Kenya. Methods Data from two cities in Kenya were gathered using a household survey and a two-stage cluster sample design. The cities were stratified based on planning and drainage observed across the urban areas. This helped control for the strong environmental and topographical variation that we assumed influences mosquito ecology. Individual interviews given to each household included questions on socio-economic status, education, housing type, water source, rubbish disposal, mosquito-prevention practices and knowledge of mosquitoes. In multivariate regression, factors measuring wealth, education level, and the communities' level of planning and drainage were used to estimate the probability that a household engages in multiple mosquito-avoidance activities, or has all members sleeping under a bed net. Results Our analysis shows that people from wealthier, more educated households were more likely to sleep under a net, in Kisumu (OR = 6.88; 95% CI = 2.56,18.49 and Malindi (OR = 3.80; 95% CI = 1.91,7.55. Similarly, the probability that households use several mosquito-prevention activities was highest among the wealthiest, best-educated households in Kisumu (OR = 5.15; 95% CI = 2.04,12.98, while in Malindi household wealth alone is the major determinant. Conclusion We demonstrate the importance of examining human-mosquito interaction in terms of how access to resources may enhance human activities. The findings illustrate that the poorest segments of society are already doing many things to protect themselves from being bitten, but they are doing less than their richer neighbours.

Githeko Andrew K

2002-11-01

334

The role of cow urine in the oviposition site preference of culicine and Anopheles mosquitoes  

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Abstract Background Chemical and behavioural ecology of mosquitoes plays an important role in the development of chemical cue based vector control. To date, studies available have focused on evaluating mosquito attractants and repellents of synthetic and human origins. This study, however, was aimed at seasonal evaluation of the efficiency of cow urine in producing oviposition cues to Anopheles gambiae s.l. and Culex quinquefasciatus in both laboratory and f...

Kweka Eliningaya J; Owino Eunice A; Mwang'onde Beda J; Mahande Aneth M; Nyindo Mramba; Mosha Franklin

2011-01-01

335

Risk factors for house-entry by culicine mosquitoes in a rural town and satellite villages in The Gambia  

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Abstract Background Screening doors, windows and eaves of houses should reduce house entry by eusynanthropic insects, including the common African house mosquito Culex pipiens quinquefasciatus and other culicines. In the pre-intervention year of a randomized controlled trial investigating the protective effects of house screening against mosquito house entry, a multi-factorial risk factor analysis study was used to identify factors influencing house entry by culicine...

Kirby Matthew J; West Philippa; Green Clare; Jasseh Momodou; Lindsay Steve W

2008-01-01

336

Implementation of a novel PCR based method for detecting malaria parasites from naturally infected mosquitoes in Papua New Guinea  

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Abstract Background Detection of Plasmodium species in mosquitoes is important for designing vector control studies. However, most of the PCR-based detection methods show some potential limitations. The objective of this study was to introduce an effective PCR-based method for detecting Plasmodium vivax and Plasmodium falciparum from the field-caught mosquitoes of Papua New Guinea. Methods A method has been developed to concurrently de...

Hasan Arif U; Suguri Setsuo; Sattabongkot Jetsumon; Fujimoto Chigusa; Amakawa Masao; Harada Masakazu; Ohmae Hiroshi

2009-01-01

337

Larval Habitat Characteristics of the Genus Anopheles (Diptera: Culicidae) and a Checklist of Mosquitoes in Guilan Province, Northern Iran  

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Background: Ecological data are important in the vector control management of mosquitoes. There is scattered pub­lished information about the larval habitat characteristics and ecology of the genus Anopheles (Diptera: Culicidae) in Iran and most of available data is in relation to malaria vectors in southern Iran.Methods: This cross sectional investigation was carried out to study the mosquito fauna and ecology in Guilan Province, northern Iran, during April–December 2000. Larvae were coll...

Azari-hamidian, S.

2011-01-01

338

An elaborated feeding cycle model for reductions in vectorial capacity of night-biting mosquitoes by insecticide-treated nets  

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Abstract Background Insecticide Treated Nets (ITNs) are an important tool for malaria control. ITNs are effective because they work on several parts of the mosquito feeding cycle, including both adult killing and repelling effects. Methods Using an elaborated description of the classic feeding cycle model, simple formulas have been derived to describe how ITNs change mosquito behaviour and the intensity of malaria transmission, as summarized by vectorial capacit...

2007-01-01

339

Cyt1A of Bacillus thuringiensis Delays Evolution of Resistance to Cry11A in the Mosquito Culex quinquefasciatus  

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Insecticides based on Bacillus thuringiensis subsp. israelensis have been used for mosquito and blackfly control for more than 20 years, yet no resistance to this bacterium has been reported. Moreover, in contrast to B. thuringiensis subspecies toxic to coleopteran or lepidopteran larvae, only low levels of resistance to B. thuringiensis subsp. israelensis have been obtained in laboratory experiments where mosquito larvae were placed under heavy selection pressure for more than 30 generations...

2005-01-01

340

Risk factors for house-entry by culicine mosquitoes in a rural town and satellite villages in The Gambia  

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Background: Screening doors, windows and eaves of houses should reduce house entry by eusynanthropic insects, including the common African house mosquito Culex pipiens quinquefasciatus and other culicines. In the pre-intervention year of a randomized controlled trial investigating the protective effects of house screening against mosquito house entry, a multi-factorial risk factor analysis study was used to identify factors influencing house entry by culicines of nuisance biting and medical i...

Kirby, M. J.; West, P.; Green, C.; Jasseh, M.; Lindsay, S. W.

2008-01-01

 
 
 
 
341

Larval midgut modifications associated with Bti resistance in the yellow fever mosquito using proteomic and transcriptomic approaches  

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Background: Bacillus thuringiensis var. israelensis ( Bti ) is a natural larval mosquito pathogen producing pore-forming toxins targeting the midgut of Diptera larvae. It is used worldwide for mosquito control. Resistance mechanisms of an Aedes aegypti laboratory strain selected for 30 generations with field-collected leaf litter containing Bti toxins were investigated in larval midguts at two levels: 1. gene transcription using DNA microarray and RT-qPCR and 2. differential expression of bru...

2012-01-01

342

Mosquito surveys and West Nile virus screening in two different areas of southern Portugal, 2004-2007.  

Science.gov (United States)

Longitudinal mosquito surveys were carried out in southern Portugal from 2004 to 2007, in a wetland area (Comporta, District of Setúbal) and around the perimeter of a dam irrigation plant that created the largest artificial lake in Europe, 250 km(2) (Alqueva, Districts of Evora and Beja). Our aim was to study the diversity, abundance, and seasonal dynamics of mosquitoes, comparing these two different areas, to screen mosquitoes for West Nile Virus (WNV), an arboviral agent already detected in Portugal, because these areas are populated with abundant avian fauna. Monthly collections of adult mosquitoes were carried out by Centers for Disease Control light-traps with CO(2) and by indoor resting collections. Mosquitoes were identified and screened for arboviruses by reverse transcriptase (RT)-polymerase chain reaction directed toward amplification of a 217-bp fragment of the NS5 gene. Mosquito peak densities were observed in July-August in Comporta and May-June, with a plateau in July-October, in Alqueva. However, densities were far higher in Comporta area (220,821 specimens) than in Alqueva area (9442 specimens), with a clear difference in species distribution, as in Comporta the predominant species was Culex theileri (85%), followed by Aedes caspius (6%), Anopheles atroparvus (4%), and Culex pipiens sensu latu (s.l.) (3%), whereas in Alqueva the predominant species was Cx. pipiens s.l. (56%), followed by An. atroparvus (18%), Cx. theileri (14%), and Culiseta longiareolata (9%). Female mosquitoes (8842 in 175 pools) of the species Ae. caspius, An. atroparvus, Culex mimeticus, Cx. pipiens Sensu latu (s.l.), Cx. theileri, and Culex univittatus were screened and found to be negative for WNV genomic RNA. Although there was no detection of WNV sequences in mosquitoes, vigilance should continue as the circulation of virus has been previously detected more than once in Portugal, in humans, animals, and mosquitoes, and in other surrounding Mediterranean countries. PMID:20854020

Almeida, António Paulo G; Freitas, Ferdinando B; Novo, Maria Teresa; Sousa, Carla A; Rodrigues, João C; Alves, Ricardo; Esteves, Aida

2010-10-01

343

Detection of arboviruses and other micro-organisms in experimentally infected mosquitoes using massively parallel sequencing.  

Science.gov (United States)

Human disease incidence attributed to arbovirus infection is increasing throughout the world, with effective control interventions limited by issues of sustainability, insecticide resistance and the lack of effective vaccines. Several promising control strategies are currently under development, such as the release of mosquitoes trans-infected with virus-blocking Wolbachia bacteria. Implementation of any control program is dependent on effective virus surveillance and a thorough understanding of virus-vector interactions. Massively parallel sequencing has enormous potential for providing comprehensive genomic information that can be used to assess many aspects of arbovirus ecology, as well as to evaluate novel control strategies. To demonstrate proof-of-principle, we analyzed Aedes aegypti or Aedes albopictus experimentally infected with dengue, yellow fever or chikungunya viruses. Random amplification was used to prepare sufficient template for sequencing on the Personal Genome Machine. Viral sequences were present in all infected mosquitoes. In addition, in most cases, we were also able to identify the mosquito species and mosquito micro-organisms, including the bacterial endosymbiont Wolbachia. Importantly, naturally occurring Wolbachia strains could be differentiated from strains that had been trans-infected into the mosquito. The method allowed us to assemble near full-length viral genomes and detect other micro-organisms without prior sequence knowledge, in a single reaction. This is a step toward the application of massively parallel sequencing as an arbovirus surveillance tool. It has the potential to provide insight into virus transmission dynamics, and has applicability to the post-release monitoring of Wolbachia in mosquito populations. PMID:23460918

Hall-Mendelin, Sonja; Allcock, Richard; Kresoje, Nina; van den Hurk, Andrew F; Warrilow, David

2013-01-01

344

Development of biodegradable aluminium carboxymethylcellulose matrices for mosquito larvicides.  

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The use of ecofriendly biodegradable controlled-release formulations of mosquito larvicides could reduce the frequency of application and losses due to degradation of the insecticide compared with conventional formulations. Among the 20 matrices developed by entrapping the organophosphorus mosquito larvicide, fenthion, in carboxymethylcellulose ionotropically cross-linked with aluminium ions which were studied for release profiles, two matrices, CRF3b and CRF5b, were found to be stable for 16 and 14 weeks under simulated field conditions. The average concentration of fenthion released per week ranged from 0.06 to 3.5 mg litre(-1) for CRF3b and 0.09 to 2.72 mg litre(-1) for CRF5b. Of these two formulations, CRF3b was the more stable, maintaining the concentration of the active ingredient at the level required to effect mosquito control. The cumulative release of fenthion per pellet was 80% from CRF3b and 72% from CRF5b. Based on the study with fenthion, two similar matrices for triflumuron, a benzoylphenylurea insect growth regulator, STAR3b and STAR5b were developed. These matrices were stable up to 16 weeks with the average concentration of triflumuron released per week ranging from 0.05 to 3.44 mg litre(-1) for STAR3b and 0.07 to 2.71 mg litre(-1) for STARSb. The cumulative release of triflumuron per pellet was 75% from STAR3b and 76% from STAR5b. From the results of this study under simulated conditions, it is estimated that the application of four pellets of either fenthion or triflumuron per square metre of the breeding surface may play a useful role in controlling Culex quinquefasciatus Say in larval habitats for about 4 months. PMID:15260300

Mathew, Nisha; Kalyanasundaram, Muthuswami

2004-07-01

345

Usage and Perceived Side Effects of Personal Protective Measures against Mosquitoes among Current Users in Delhi.  

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Background. Mosquito-borne diseases constitute an important cause of morbidity and mortality. The use of personal protective measures (PPM) like mats, bednets, screening, repellents, liquid vaporizers, mosquito coils, and so forth has been advocated as an effective tool in control of mosquito-borne diseases, but data about the safety profile of personal protective measures is still scarce. Objective. To study the usage and side effects of personal protective measures against mosquitoes among current users in Delhi. Materials and Methods. A community-based cross-sectional study among 350 adult individuals selected by systematic sampling method. Data was collected using pretested semistructured questionnaire after taking written informed consent. Data was analysed using SPSS version 17. Chi-square/Fisher's Exact test was used for qualitative variables to find association and P value <0.05 was considered significant. Results. Out of 350 families selected, 210 belonged to rural area and 140 to urban area. Personal protective measures were used by 219 (62.5%) subjects. Liquid vaporizer was the most preferred method (41.4%). Most common perceived side effect of personal protective measures was headache (7.7%). Other perceived side effects were cough (3.2%), sore throat (2.7%), allergy (1.3%), and eye irritation (0.9%) predominantly among coil users. Conclusion. There is a need to have a close watch for side effects of personal protective measures among users. Further research is also needed to develop safe and effective personal protective measures against mosquitoes. PMID:24616805

Kohli, Charu; Kumar, Rajesh; Meena, G S; Singh, M M; Sahoo, Jyotiranjan; Ingle, G K

2014-01-01

346

COMPARATIVE ASSESSMENT OF MOSQUITO BIOCONTROL EFFICIENCY BETWEEN GUPPY (POECILIA RETICULATA AND PANCHAX MINNOW (APLOCHEILUS PANCHAX  

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Full Text Available The present work was designed to compare the mosquito biocontrol efficiency of guppy and panchax minnow, the two popular fish species which so far have been used for mosquito biocontrol here in India. Study of the predation efficiency in relation to fish size and larval size has revealed significant better predation efficiency of panchax minnow over guppy in all size groups except for pupae in small size group fishes. Study of the comparative predation efficiency under vegetative cover has revealed significant (P<0.01 higher predation efficiency for panchax minnow over guppy. Study of the comparative predation efficiency under different depth of water has revealed superior predation efficiency of guppy under shallow water depth whereas panchax minnow has shown significantly better predation efficiency with increasing water depth. So, panchax minnow is a better mosquito biocontrol agent in waterbodies with vegetative covering and in comparatively deep water bodies whereas guppy can be used for mosquito control in very shallow water depth. But overall the study has depicted the superiority of panchax minnow over guppy as mosquito biocontrol agent.

Sandipan Gupta and Samir Banerjee

2013-01-01

347

A viral over-expression system for the major malaria mosquito Anopheles gambiae.  

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Understanding pathogen/mosquito interactions is essential for developing novel strategies to control mosquito-borne diseases. Technical advances in reverse-genetics, such as RNA interference (RNAi), have facilitated elucidation of components of the mosquito immune system that are antagonistic to pathogen development, and host proteins essential for parasite development. Forward genetic approaches, however, are limited to generation of transgenic insects, and while powerful, mosquito transgenesis is a resource- and time-intensive technique that is not broadly available to most laboratories. The ability to easily "over-express" genes would enhance molecular studies in vector biology and expedite elucidation of pathogen-refractory genes without the need to make transgenic insects. We developed and characterized an efficient Anopheles gambiae densovirus (AgDNV) over-expression system for the major malaria vector Anopheles gambiae. High-levels of gene expression were detected at 3 days post-infection and increased over time, suggesting this is an effective system for gene induction. Strong expression was observed in the fat body and ovaries. We validated multiple short promoters for gene induction studies. Finally, we developed a polycistronic system to simultaneously express multiple genes of interest. This AgDNV-based toolset allows for consistent transduction of genes of interest and will be a powerful molecular tool for research in Anopheles gambiae mosquitoes. PMID:24875042

Suzuki, Yasutsugu; Niu, Guodong; Hughes, Grant L; Rasgon, Jason L

2014-01-01

348

Identification and Characterization of Seminal Fluid Proteins in the Asian Tiger Mosquito, Aedes albopictus  

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The Asian tiger mosquito (Aedes albopictus) is an important vector for pathogens that affect human health, including the viruses that cause dengue and Chikungunya fevers. It is also one of the world's fastest-spreading invasive species. For these reasons, it is crucial to identify strategies for controlling the reproduction and spread of this mosquito. During mating, seminal fluid proteins (Sfps) are transferred from male mosquitoes to females, and these Sfps modulate female behavior and physiology in ways that influence reproduction. Despite the importance of Sfps on female reproductive behavior in mosquitoes and other insects, the identity of Sfps in Ae. albopictus has not previously been reported. We used transcriptomics and proteomics to identify 198 Sfps in Ae. albopictus. We discuss possible functions of these Sfps in relation to Ae. albopictus reproduction-related biology. We additionally compare the sequences of these Sfps with proteins (including reported Sfps) in several other species, including Ae. aegypti. While only 72 (36.4%) of Ae. albopictus Sfps have putative orthologs in Ae. aegypti, suggesting low conservation of the complement of Sfps in these species, we find no evidence for an elevated rate of evolution or positive selection in the Sfps that are shared between the two Aedes species, suggesting high sequence conservation of those shared Sfps. Our results provide a foundation for future studies to investigate the roles of individual Sfps on feeding and reproduction in this mosquito. Functional analysis of these Sfps could inform strategies for managing the rate of pathogen transmission by Ae. albopictus.

Boes, Kathryn E.; Ribeiro, Jose M. C.; Wong, Alex; Harrington, Laura C.; Wolfner, Mariana F.; Sirot, Laura K.

2014-01-01

349

On the analysis of effectiveness in mass application of mosquito repellent for dengue disease prevention  

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Dengue disease has been known as one of dangerous vector-borne diseases and become serious threat in many tropical countries. With no vaccine and antiviral available until nowadays, and frequent appearance of extraordinary dengue outbreaks, many governments are forced to declare national problem for dengue. At this moment, the only method available to prevent dengue disease transmission is to combat the disease-carrying mosquitoes as well as to reduce the contact between human and mosquitoes. The fast growing dengue transmission in many countries in recent years indicates that the mosquito control programs are far from successful. The use of mosquito repellent is one possible instrument which could be used as an effective mass treatment to prevent the dengue outbreak during endemic period. Here in this paper a Susceptible-Infectious-Recovered (S-I-R) dengue transmission model with repellent mass treatment is being applied to portions of children and adult compartments. Analysis of the basic reproductive ratio (Ro) of the model is done. It is shown, with reasonable choices of portions of treated children and adults, in combination with reduction of mosquito population, the basic reproductive ratio can be significantly reduced and occurrence of endemic can be avoided. Numerical simulations are shown for various treatment scenarios.

Aldila, D.; Soewono, E.; Nuraini, N.

2012-05-01

350

Identification and Characterization of Seminal Fluid Proteins in the Asian Tiger Mosquito, Aedes albopictus.  

Science.gov (United States)

The Asian tiger mosquito (Aedes albopictus) is an important vector for pathogens that affect human health, including the viruses that cause dengue and Chikungunya fevers. It is also one of the world's fastest-spreading invasive species. For these reasons, it is crucial to identify strategies for controlling the reproduction and spread of this mosquito. During mating, seminal fluid proteins (Sfps) are transferred from male mosquitoes to females, and these Sfps modulate female behavior and physiology in ways that influence reproduction. Despite the importance of Sfps on female reproductive behavior in mosquitoes and other insects, the identity of Sfps in Ae. albopictus has not previously been reported. We used transcriptomics and proteomics to identify 198 Sfps in Ae. albopictus. We discuss possible functions of these Sfps in relation to Ae. albopictus reproduction-related biology. We additionally compare the sequences of these Sfps with proteins (including reported Sfps) in several other species, including Ae. aegypti. While only 72 (36.4%) of Ae. albopictus Sfps have putative orthologs in Ae. aegypti, suggesting low conservation of the complement of Sfps in these species, we find no evidence for an elevated rate of evolution or positive selection in the Sfps that are shared between the two Aedes species, suggesting high sequence conservation of those shared Sfps. Our results provide a foundation for future studies to investigate the roles of individual Sfps on feeding and reproduction in this mosquito. Functional analysis of these Sfps could inform strategies for managing the rate of pathogen transmission by Ae. albopictus. PMID:24945155

Boes, Kathryn E; Ribeiro, José M C; Wong, Alex; Harrington, Laura C; Wolfner, Mariana F; Sirot, Laura K

2014-06-01

351

Preliminary analysis of several attractants and spatial repellents for the mosquito, Aedes albopictus using an olfactometer.  

Science.gov (United States)

Mosquito attractants and spatial repellents hold great promise in controlling mosquito pests. In assessing the effectiveness of mosquito attractants and repellents, a good olfactometer system, and optimized testing conditions, are essential. In this research, we demonstrated the usefulness of an olfactometer system, and optimized testing conditions for Aedes albopictus (Diptera: Culicidae). We found no significant difference in the biting activity of the insect between 8:00 and 22:00. Furthermore, 5-10 day old mosquitoes were relatively strongly attracted, with bloodsucking rate 75.8%. The random capture rate (entered trap in absence of odor) was less than 20% for the 20-40 tested insects. Capture rates and systematic errors increased as the number of testing insects increased. Wind speed affected the capture rate significantly, whereas variations in temperature between 25-28°C did not result in significant difference. The wind speed of 0.2 m/s exhibited a higher capture rate, which was significantly different from those at either 0.1 m/s or 0.4 m/s (P citronellal, citral, and linalool all exhibited some inhibition effect on mosquitoes to successfully trace human odor or 1% of L-lactic acid in dichloromethane. The results of these two tests indicate that the L-lactic acid/dichloromethane mixture may be used as an effective attractant to evaluate the effect of possible spatial repellents on Ae. albopictus. PMID:23418948

Hao, Huiling; Sun, Jingcheng; Dai, Jianqing

2012-01-01

352

Preliminary Analysis of Several Attractants and Spatial Repellents for the Mosquito, Aedes albopictus using an Olfactometer  

Science.gov (United States)

Mosquito attractants and spatial repellents hold great promise in controlling mosquito pests. In assessing the effectiveness of mosquito attractants and repellents, a good olfactometer system, and optimized testing conditions, are essential. In this research, we demonstrated the usefulness of an olfactometer system, and optimized testing conditions for Aedes albopictus (Diptera: Culicidae). We found no significant difference in the biting activity of the insect between 8:00 and 22:00. Furthermore, 5–10 day old mosquitoes were relatively strongly attracted, with bloodsucking rate 75.8%. The random capture rate (entered trap in absence of odor) was less than 20% for the 20–40 tested insects. Capture rates and systematic errors increased as the number of testing insects increased. Wind speed affected the capture rate significantly, whereas variations in temperature between 25–28°C did not result in significant difference. The wind speed of 0.2 m/s exhibited a higher capture rate, which was significantly different from those at either 0.1 m/s or 0.4 m/s (P citronellal, citral, and linalool all exhibited some inhibition effect on mosquitoes to successfully trace human odor or 1% of L-lactic acid in dichloromethane. The results of these two tests indicate that the L-lactic acid/dichloromethane mixture may be used as an effective attractant to evaluate the effect of possible spatial repellents on Ae. albopictus.

Hao, Huiling; Sun, Jingcheng; Dai, Jianqing

2012-01-01

353

Repellent Action Of Neem (Azadiracta India Seed Oil Against Aedes Aegypti Mosquitoes  

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Full Text Available Neem (Azadiracta India seed oil in appropriate amount when smeared on the surface of the hand showed excellent repellent action against Aedes aegypti mosquitoes. When 1 ml of oil was spread on the hand, with an approximate area of 160 sq cm the percentage of alighting and blood fed mosquitoes in the experimental cages varied from 14 to 78 and 4 to 46 respectively. This percentage decreased to 6 to 18 and 0 to 16 respectively when the amount of oil applied was 1.5 ml. Only 0-4% of the mosquitoes alighted on the skin of which 2% only took the blood meal when 2 ml of the oil was used to cover the hand. In the control cages cent percent of the mosquitoes alighted and sucked blood. The repellent action was directly proportional to the hour of exposure to the oil. It was also observed that even after alighting on a oil- smeared skin a sizeable proportion of mosquitoes were not able to imbibe blood meal. Neem seed oil was non-toxic, non- irritating to skin.

Hati A K

1995-01-01

354

Mosquito larvae change their feeding behavior in response to kairomones from some predators.  

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The efficacy of using predators for the biological control of mosquito disease vectors will be reduced if mosquito larvae respond to predator presence. The larvae of two mosquito species were investigated to study whether they responded to predator kairomones by increasing surface filter-feeding, which is a less active and thus less risky feeding strategy than bottom feeding. Culex quinquefasciatus Say is normally found in highly polluted water, where it will have little contact with predators. Except for some third instars, its larvae showed no response to four different types of predators. Culiseta longiareolata Macquart, living in rain-filled rock pools, is frequently attacked by a range of predators. All instars tested (second, third, and fourth instars) strongly responded to chemicals from dragonfly nymphs (Crocothemis erythraea Brullé), damselfly nymphs (Ischnura evansi Morton), and the fish Aphanius dispar Ruppel. However, they did not respond to final-instar water scorpions (Nepa cinerea L.), which would not feed on the mosquito larvae. Second- and third-instar Cs. longiareolata produced the same response to chopped up mosquito larvae as they did to dragonfly nymphs, but fourth instars produced a significantly stronger response to dragonfly nymphs-both those unfed and those fed in situ. Thus, Cs. longiareolata not only identified different predators and responded accordingly, but also responded to conspecific alarm pheromones. Cx quinquefasciatus showed little response to predators or to alarm pheromones from damaged conspecific larvae. PMID:24724285

Roberts, Derek

2014-03-01

355

Usage and Perceived Side Effects of Personal Protective Measures against Mosquitoes among Current Users in Delhi  

Science.gov (United States)

Background. Mosquito-borne diseases constitute an important cause of morbidity and mortality. The use of personal protective measures (PPM) like mats, bednets, screening, repellents, liquid vaporizers, mosquito coils, and so forth has been advocated as an effective tool in control of mosquito-borne diseases, but data about the safety profile of personal protective measures is still scarce. Objective. To study the usage and side effects of personal protective measures against mosquitoes among current users in Delhi. Materials and Methods. A community-based cross-sectional study among 350 adult individuals selected by systematic sampling method. Data was collected using pretested semistructured questionnaire after taking written informed consent. Data was analysed using SPSS version 17. Chi-square/Fisher's Exact test was used for qualitative variables to find association and P value <0.05 was considered significant. Results. Out of 350 families selected, 210 belonged to rural area and 140 to urban area. Personal protective measures were used by 219 (62.5%) subjects. Liquid vaporizer was the most preferred method (41.4%). Most common perceived side effect of personal protective measures was headache (7.7%). Other perceived side effects were cough (3.2%), sore throat (2.7%), allergy (1.3%), and eye irritation (0.9%) predominantly among coil users. Conclusion. There is a need to have a close watch for side effects of personal protective measures among users. Further research is also needed to develop safe and effective personal protective measures against mosquitoes.

Kumar, Rajesh; Meena, G. S.; Singh, M. M.; Sahoo, Jyotiranjan; Ingle, G. K.

2014-01-01

356

Mosquito larvicidal and antimicrobial activity of protein of Solanum villosum leaves  

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Full Text Available Abstract Background Mosquitoes are associated with the transmission of malaria, dengue, Japanese encephalitis, filariasis and other viral diseases throughout the globe, apart from being a nuisance pest. Biological control alone or as a part of integrated vector management stands to be a better alternative to the chemical controls aimed against pest mosquitoes. At the same time it is necessary to control bacteria by synthetic or natural means (plant products. Hence the present study was designed to screen the effect of mosquito larvicidal and antimicrobial activitiy of protein isolated from matured leaves of Solanum villosum against mosquito immatures and some pathogenic bacteria. Methods Aqueous solvent extract of fresh mature leaves of S. villosum was tested against 3rd instar larvae of Anopheles stephensi, Culex quinquefasciatus and Stegomyia aegypti mosquitoes and against four pathogenic bacteria. The protein fraction was isolated and tested for mosquitocidal and antibacterial activities. Amino acid analysis was performed on isolated protein using PICO.TAG amino acid system. SDS-PAGE was also done to detect the bands of amino acid on the basis of their molecular weights. Results Proteins isolated from mature leaves of S. villosum were found to have larvicidal and antimicrobial properties. Analysis of the isolated protein identified fifteen amino acids of which eight were essential amino acids. SDS-PAGE detected seven bands corresponding to different molecular weights in the range of 69–109 KDa. Conclusion Proteins of mature leaves of S. villosum exhibited moderate larvicidal and antimicrobial activities. The study provides considerable scope in exploiting local indigenous resources for isolation of antimicrobial and mosquito larvicidal proteins.

Chandra Goutam

2008-12-01

357

Mayaro virus isolated from a Trinidadian mosquito, Mansonia venezuelensis.  

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A strain of Mayaro virus has been isolated in Trinidad from the mosquito Mansonia venezuelensis. This is the first record of isolation of this agent from naturally infected mosquitoes, caught in the wild. PMID:13792204

AITKEN, T H; DOWNS, W G; ANDERSON, C R; SPENCE, L; CASALS, J

1960-04-01