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1.
Acta Trop ; 242: 106891, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36907292

RESUMO

Mosquitoes are extensively responsible for the transmission of pathogens. Novel strategies using Wolbachia could transform that scenario, since these bacteria manipulate mosquito reproduction, and can confer a pathogen transmission-blocking phenotype in culicids. Here, we screened the Wolbachia surface protein region by PCR in eight Cuban mosquito species. We confirmed the natural infections by sequencing and assessed the phylogenetic relationships among the Wolbachia strains detected. We identified four Wolbachia hosts: Aedes albopictus, Culex quinquefasciatus, Mansonia titillans, and Aedes mediovittatus (first report worldwide). Knowledge of Wolbachia strains and their natural hosts is essential for future operationalization of this vector control strategy in Cuba.


Assuntos
Aedes , Wolbachia , Animais , Wolbachia/genética , Filogenia , Cuba , Mosquitos Vetores/microbiologia , Aedes/microbiologia
2.
Parasit Vectors ; 15(1): 453, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36471389

RESUMO

BACKGROUND: Hawai'i's native forest avifauna is experiencing drastic declines due to climate change-induced increases in temperature encroaching on their upper-elevation montane rainforest refugia. Higher temperatures support greater avian malaria infection rates due to greater densities of its primary vector, the southern house mosquito Culex quinquefasciatus, and enhance development of the avian malaria parasite Plasmodium relictum. Here we propose the use of the incompatible insect technique (IIT) or the combined IIT/sterile insect technique (SIT) for the landscape-scale (i.e., area-wide) control of Cx. quinquefasciatus, and have developed a calculator to estimate the costs of IIT and IIT/SIT applications at various sites in Hawai'i. METHODS: The overall cost of the infrastructure, personnel, and space necessary to produce incompatible adult males for release is calculated in a unit of ~ 1 million culicid larvae/week. We assessed the rearing costs and need for effective control at various elevations in Hawai'i using a 10:1 overflooding ratio at each elevation. The calculator uses a rate describing the number of culicids needed to control wild-type mosquitoes at each site/elevation, in relation to the number of larval rearing units. This rate is a constant from which other costs are quantified. With minor modifications, the calculator described here can be applied to other areas, mosquito species, and similar techniques. To test the robustness of our calculator, the Kaua'i-specific culicid IIT/SIT infrastructure costs were also compared to costs from Singapore, Mexico, and China using the yearly cost of control per hectare, and purchasing power parity between sites for the cost of 1000 IIT/SIT males. RESULTS: As a proof of concept, we have used the calculator to estimate rearing infrastructure costs for an application of IIT in the Alaka'i Wilderness Reserve on the island of Kaua'i. Our analysis estimated an initial investment of at least ~ $1.16M with subsequent yearly costs of approximately $376K. Projections of rearing costs for control at lower elevations are ~ 100 times greater than in upper elevation forest bird refugia. These results are relatively comparable to those real-world cost estimates developed for IIT/SIT culicid male production in other countries when inflation and purchasing power parity are considered. We also present supplemental examples of infrastructure costs needed to control Cx. quinquefasciatus in the home range of 'i'iwi Drepanis coccinea, and the yellow fever vector Aedes aegypti. CONCLUSIONS: Our cost calculator can be used to effectively estimate the mass rearing cost of an IIT/SIT program. Therefore, the linear relationship of rearing infrastructure to costs used in this calculator is useful for developing a conservative cost estimate for IIT/SIT culicid mass rearing infrastructure. These mass rearing cost estimates vary based on the density of the targeted organism at the application site.


Assuntos
Aedes , Culex , Malária Aviária , Passeriformes , Animais , Masculino , Culex/parasitologia , Malária Aviária/parasitologia , Havaí , Mosquitos Vetores , Passeriformes/parasitologia , Insetos
3.
Rev. cuba. med. trop ; 68(2): 111-124, may.-ago. 2016. tab
Artigo em Espanhol | LILACS, CUMED | ID: biblio-844984

RESUMO

Introducción: el aumento de enfermedades transmitidas por mosquitos se ha asociado a cambios globales: el crecimiento de la población, la urbanización y el cambio climático. Dentro de las alternativas para evitar epidemias están el control químico y biológico. Objetivos: determinar las concentraciones efectivas de tres compuestos químicos para el control de larvas de Aedes aegypti en la región costa norte de Jalisco, México, y evaluar la capacidad predatoria de diversas especies acuáticas sobre larvas de mosquitos. Métodos: se evaluaron cinco concentraciones de temefos (1,5; 1; 0,1; 0,05 y 0,01 g/L), hipoclorito de sodio (5,5; 0,55; 0,05; 0,005 y 0,0005 g/L) y detergente (10; 5; 1; 0,5; 0,1 g/L). Se determinó la muerte de las larvas a 1, 3, 6 y 24 h y se calculó la CL50. Se evaluaron cuatro especies de peces, un crustáceo y una larva de díptero culícido. Se les suministraron diferentes cantidades de larvas (5, 10, 30, 50 y 80) por quintuplicado y se registró su consumo a diferentes tiempos (1, 3, 5, 9 y 24 h). Resultados: el temefos provocó el 100 por ciento de mortalidad en todas las concentraciones probadas. El NaClO provocó mortalidad del 100 por ciento en las dos concentraciones más altas. El detergente fue más eficiente a las tres concentraciones mayores. Los peces demostraron un consumo de casi el 100 por ciento en la mayoría de las densidades probadas. La larva de díptero culícido demostró un consumo cercano al 80 por ciento, el crustáceo solo consumió el 53 por ciento Conclusiones: el uso del temefos debe continuar siendo el larvicida químico de elección en Puerto Vallarta, México. La utilización de peces nativos se sugiere como adecuada para el control biológico(AU)


Introduction: the increase of diseases transmitted by mosquitoes has been associated to global changes such as the population growth, urbanization and climate change. Among the alternatives to avoid epidemics are the chemical and biological control. Objectives: to determine effective concentrations of three chemical compounds to control Aedes aegypti larvae in the northern coastal region of Jalisco and to evaluate the predatory ability of various aquatic species on mosquito larvae. Methods: five concentrations of temephos of (1.5, 1, 0.1; 0.05 and 0.01 g/L), sodium hypochlorite (5.5, 0.55, 0.05, 0,005 and 0.0005 g/L) and detergent (10, 5, 1, 0.5, 0.1 g/L) were evaluated. Larval death was estimated at different times (1, 3, 5, 9 and 24 h) and the LC50 was calculated. Four fish species, one crustacean and one dipteral culicid larva were evaluated. All were provided with different numbers of larvae (5, 10, 30, 50 and 80) five times and the larval consumption was recorded at different times (1, 3, 5, 9 and 24 h). Results: temephos caused 100 percent mortality of larvae in all tested concentrations. The NaClO caused 100 percent mortality at the two highest concentrations. The detergent was more efficient at the three higher concentrations. Fish proved to be efficient predators of larvae, as they consumed almost 100 percent of larvae in most of tested densities. The diptera culicid larva reached around 80 percent consumption whereas crustacean consumed only 53 percent. Conclusions: the use of temephos should remain the chemical larvicide of choice in Puerto Vallarta region. Native fish are suggested to be used as appropriate biological control agents(AU)


Assuntos
Temefós , Controle Biológico de Vetores/métodos , Aedes , Larva , México
4.
J Med Entomol ; 52(5): 770-82, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26336249

RESUMO

The incredible mosquito species diversity in the Neotropics can provoke major confusion during vector control programs when precise identification is needed. This is especially true in French Guiana where studies on mosquito diversity practically ceased 35 yr ago. In order to fill this gap, we propose here an updated and comprehensive checklist of the mosquitoes of French Guiana, reflecting the latest changes in classification and geographical distribution and the recognition of current or erroneous synonymies. This work was undertaken in order to help ongoing and future research on mosquitoes in a broad range of disciplines such as ecology, biogeography, and medical entomology. Thirty-two valid species cited in older lists have been removed, and 24 species have been added including 12 species (comprising two new genera and three new subgenera) reported from French Guiana for the first time. New records are from collections conducted on various phytotelmata in French Guiana and include the following species: Onirion sp. cf Harbach and Peyton (2000), Sabethes (Peytonulus) hadrognathus Harbach, Sabethes (Peytonulus) paradoxus Harbach, Sabethes (Peytonulus) soperi Lane and Cerqueira, Sabethes (Sabethinus) idiogenes Harbach, Sabethes (Sabethes) quasicyaneus Peryassú, Runchomyia (Ctenogoeldia) magna (Theobald), Wyeomyia (Caenomyiella) sp. cf Harbach and Peyton (1990), Wyeomyia (Dendromyia) ypsipola Dyar, Wyeomyia (Hystatomyia) lamellata (Bonne-Wepster and Bonne), Wyeomyia (Miamyia) oblita (Lutz), and Toxorhynchites (Lynchiella) guadeloupensis (Dyar and Knab). At this time, the mosquitoes of French Guiana are represented by 235 species distributed across 22 genera, nine tribes, and two subfamilies.


Assuntos
Distribuição Animal , Culicidae/classificação , Culicidae/fisiologia , Animais , Feminino , Guiana Francesa , Masculino
5.
Medisan ; 17(2): 166-173, feb. 2013.
Artigo em Espanhol | LILACS | ID: lil-667898

RESUMO

Se efectuó un estudio observacional, descriptivo y transversal, a fin de caracterizar algunas variables entomológicas de la vigilancia de culícidos transmisores de paludismo en Santiago de Cuba, desde 2006 hasta 2010. El universo de estudio se agrupó según los métodos establecidos para las colectas larvales de Anopheles albimanus. Se realizaron 602 encuestas larvarias donde existían focos de culícidos sujetos a vigilancia. Finalmente se demostró que 19,6 % de los criaderos fueron positivos a la especie antes citada. Asimismo, la densidad larvaria general fue de 13,4 larvas/m² y la específica de 1,8 larvas/m², con una tendencia al incremento de la positividad en estos criaderos. Se recomendó mantener una estrecha vigilancia en las áreas donde circulaba este vector.


An observational, descriptive and cross-sectional study was carried out, in order to characterize some entomological variables of the surveillance of culicids transmitting malaria in Santiago de Cuba, from 2006 to 2010. The study universe was formed according to the established methods for the larval collections of Anopheles albimanus. There were 602 larval interviews carried out in the culicids breeding under surveillance. Finally it was demonstrated that 19.6 % of the breedings were positive for the above mentioned species. Also, the larval general density was 13.4 larvae/m² and the specific of 1.8 larvae/m², with a tendency to the increase of positive results in these breedings. It was recommended to maintain a closed surveillance in the areas where this vector circulated.

6.
Rev. bras. entomol ; 55(1): 134-137, Jan.-Mar. 2011. ilus, graf
Artigo em Inglês | LILACS-Express | LILACS, Sec. Est. Saúde SP | ID: lil-586073

RESUMO

Wing diagnostic characters for Culex quinquefasciatus and Culex nigripalpus (Diptera, Culicidae). Culex quinquefasciatus and Culex nigripalpus are mosquitoes of public health interest, which can occur sympatrically in urban and semi-urban localities. Morphological identification of these species may be difficult when specimens are not perfectly preserved. In order to suggest an alternative taxonomical diagnosis, wings of these species were comparatively characterized using geometric morphometrics. Both species could be distinguished by wing shape with accuracy rates ranging from 85-100 percent. Present results indicate that one can identify these species relying only on wing characters when traditional taxonomical characters are not visible.


Caracteres alares diagnósticos de Culex quinquefasciatus and Culex nigripalpus (Diptera, Culicidae). Culex quinquefasciatus e Culex nigripalpus são mosquitos de interesse à saúde pública e que podem ocorrer em simpatria em ambientes urbanos e semi-urbanos. A identificação morfológica dessas espécies pode ser difícil nos casos em que os espécimes não estão bem preservados. Com o intuito de sugerir um método diagnóstico taxonômico, asas de indivíduos dessas espécies foram caracterizadas comparativamente utilizando-se morfometria geométrica. Ambas as espécies puderam ser distinguidas pela forma alar com índices de confiabilidade entre 85-100 por cento. Os resultados presentes indicam que é possível identificar essas espécies baseando-se apenas no formato alar, nos casos em que os caracteres taxonômicos tradicionais não são visíveis.

7.
J Nematol ; 16(4): 371-5, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19294040

RESUMO

Heydenius dominicus n. sp. is described as a new species of fossil mermithid nematode from Dominican Republic amber. The species is represented by two specimens of parasitic juveniles that left their insect host and became embedded in the resin. The nematodes are associated with an adult male limoniid (Diptera: Limoniidae) and an adult female mosquito (Diptera: Culicidae). The parasites are thought to have emerged from the mosquito host. This is the first report of a fossil mermithid from a Neotropical area.

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