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1.
São Paulo; s.n; 2023. 44 p.
Thesis in Portuguese | LILACS | ID: biblio-1511090

ABSTRACT

Objetivos: Identificar espécies de anofelinos presentes na região do Vale do Ribeira, Sudeste de São Paulo, e a circulação de plasmódios por estes anofelinos. Método: Foram utilizadas armadilhas CDC com atração luminosa e armadilhas de Shannon no período que compreende das 17:00 às 22:00 horas e atração por humano protegido realizadas das 9:00 às 12:00 horas durante três dias consecutivos em seis campanhas, realizadas de setembro de 2021 a novembro de 2022. Os espécimes capturados foram identificados morfologicamente, separados por espécie e tiveram seu DNA genômico extraído em grupos de até 10 mosquitos, considerando os métodos de captura, locais, datas e horas. Os grupos de DNA genômico foram analisados utilizando tecnologia de PCR em tempo real para amplificar fragmento de 157 a 165 pares de bases da unidade 18S do DNA ribossômico, que permite identificar a presença de plasmódios. As amostras positivas foram submetidas a técnicas de PCR aninhado de fragmento do gene citocromo b do genoma mitocondrial. De oito amostras analisadas, duas foram positivas e tiveram seus amplicons sequenciados empregando tecnologia de Sanger. Resultados: Foram coletados 5.577 mosquitos classificados no gênero Kerteszia (99,62%) e gênero Anopheles (0,38%), agrupados em 811 grupos. Foram identificados oito grupos positivos para plasmódios, sendo um para Plasmodium vivax / Plasmodium simium, um para Plasmodium malariae / Plasmodium brasilianum, dois para Plasmodium falciparum e quatro grupos positivos apenas para Plasmodium spp. O sequenciamento Sanger confirmou a infecção por P. vivax / P. simium em uma amostra, e P. malariae / P. brasilianum em outra. A proporção total de anofelinos infectados por Plasmodium spp. foi 0,5% (4/811), 0,2% dos anofelinos coletados apresentavam infecção por P. falciparum (2/811), 0,1% apresentavam infecção por P. vivax (1/811) e a mesma proporção de infectados por P. malariae (1/811). A razão mínima de infecção (RMI) para Plasmodium spp. nos anofelinos coletados foi 0,125, para P. vivax foi 0,02, assim como para P. malariae e, para P. falciparum foi 0,035. As estimativas de razão entre mosquitos infectados e mosquitos coletados foram 0,007 para Plasmodium spp., 0,0002 para P. vivax, 0,0005 para P. falciparum e 0,0005 para P. malariae. A razão de infecção absoluta por P. vivax foi 0,02 em março de 2022 e 0,01 por P. falciparum em novembro de 2022 no mesmo ponto de coleta. Conclusão: Foi identificada a presença de plasmódios zoonóticos em área de reserva da Mata Atlântica do sudeste brasileiro, onde a presença de hospedeiros humanos é restrita aos moradores, turistas, trabalhadores da reserva e pesquisadores. A densidade de mosquitos infectados por P. falciparum foi maior do que a de P. vivax e P. malariae. O encontro de mosquitos, naturalmente, infectados por estas espécies de plasmódios indica a necessidade de programas de educação ambiental delineados aos frequentadores e moradores da região da reserva e do entorno. Acresce considerar a necessidade de pesquisas detalhadas sobre as taxas de Plasmodium ocorrendo na área estudada e na Mata Atlântica, com sequenciamentos dos genomas das espécies que são encontradas em localidades diversas do Brasil e América Latina.


Objectives: Identify species of anophelines present in the Vale do Ribeira region, Southeast of São Paulo, and the circulation of plasmodia by these anophelines. Method: CDC light traps and Shannon traps were used in the period from 5:00 p.m. to 10:00 p.m. and attraction by protected human carried out from 9:00 a.m. to 12:00 p.m. for three consecutive days in 6 campaigns, carried out from September 2021 to November 2022. The captured specimens were morphologically identified, separated by species, and had their genomic DNA extracted in pools of up to 10 mosquitoes, considering capture methods, locations, dates and time. By utilizing real-time PCR technology, a 157 to 165 base pairs segment of the 18S ribosomal DNA unit was amplified to identify plasmodia within the genomic DNA pools. The positive samples were submitted to nested PCR techniques of cytochrome b gene fragment of the mitochondrial genome. Of 8 samples analyzed, two were positive and had their amplicons sequenced using Sanger technology. Results: A total of 5,577 mosquitoes belonging to the genus Kerteszia (99.62%) and to the genus Anopheles (0.38%) were collected, grouped into 811 pools. Eight positive pools for plasmodia were identified, one for Plasmodium vivax / Plasmodium simium, one for Plasmodium malariae / Plasmodium. brasilianum, two for Plasmodium falciparum and four pools positive only for Plasmodium spp. Sanger sequencing confirmed P. vivax / P. simium infection in one sample, and P. malariae / P. brasilianum in the other. The total proportion of anophelines infected with Plasmodium spp. was 0.5% (4/811), 0.2% of the collected anophelines had P. falciparum infection (2/811), 0.1% had P. vivax infection (1/811) and the same proportion of infected with P. malariae (1/811). The minimum infection rate (MIR) for Plasmodium spp. in anophelines collected was 0.125, for P. vivax was 0.02, as well as for P. malariae, and for P. falciparum it was 0.035. The ratio estimates between infected and collected mosquitoes were 0.007 for Plasmodium spp., 0.0002 for P. vivax, 0.0005 for P. falciparum, and 0.0005 for P. malariae. The absolute infection ratio for P. vivax was 0.02 in March 2022 and 0.01 for P. falciparum infection in November 2022 at the same collection point. Conclusion: The presence of zoonotic plasmodia was identified in a reserve area of the Atlantic Forest in southeastern Brazil, where the presence of human hosts is restricted to residents, tourists, reserve workers and researchers. The density of mosquitoes infected with P. falciparum was higher than that of P. vivax and P. malariae. The finding of mosquitoes naturally infected by these species of plasmodia shows the need for environmental education programs designed for visitors and residents of the reserve region and surroundings. In addition, consider the need for detailed research on the rates of Plasmodium occurring in the studied area and in the Atlantic Forest, with sequencing of the genomes of the species that are found in different locations in Brazil and Latin America.


Subject(s)
Plasmodium , Malaria , Anopheles
2.
Braz. j. biol ; 83: e248122, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1355851

ABSTRACT

Abstract Being vector of West Nile Virus and falariasis the control of Culex quinquefasciatus is likely to be essential. Synthetic insecticide treatment is looking most effective for vectors mosquito control. However, these products are toxic to the environment and non-target organisms. Consequently, ecofriendly control of vectors mosquito is needed. In this regard botanical insecticide is looking more fruitful. Therefore, the present research aimed to investigate the effectiveness of methanolic extract and various fractions, including, n-hexane, ethyl-acetate, chloroform, and aqueous fraction, obtained from methanolic extract of Ailanthus altissima, Artemisia scoparia, and Justicia adhatoda using separating funnel against larval, pupal, and adult stages of Culex quinquefasciatus. The larvae and pupae of Culex quinquefasciatus were exposed to various concentrations (31.25-1000 ppm) of methanolic extract and its fractions for 24 hours of exposure period. For knock-down bioassay (filter paper impregnation bioassay) different concentration of the methanolic extract and its various fractions (i.e. 0.0625, 0.125, 0.25, 0.5 and 1mg/mL) were applied for 1 hour exposure period. The results were statistically analysed using standard deviation, probit analysis, and linear regression. The R2 values of larvae, pupae, and adult range from 0.4 to 0.99. The values of LC50 (concentration causing 50% mortality) for late 3rd instar larvae after 24 hours exposure period range from 93-1856.7 ppm, while LC90 values range from 424 -7635.5ppm. The values of LC50for pupae range form 1326.7-6818.4ppm and and values of LC90 range from 3667.3-17427.9ppm, respectively. The KDT50 range from 0.30 to 2.8% and KDT90 values range from1.2 to 110.8%, respectively. In conclusion, Justicia adhatoda may be effective for controlling populations of vector mosquito.


Resumo Por ser o vetor do vírus do Nilo Ocidental e da falaríase, o controle de Culex quinquefasciatus Say é provavelmente essencial. O tratamento com inseticida sintético parece ser mais eficaz para o controle dos mosquitos vetores. No entanto, esses produtos são tóxicos para o meio ambiente e organismos não visados. Consequentemente, o controle ecológico dos mosquitos vetores é necessário. Nesse sentido, o inseticida botânico parece mais produtivo. Portanto, a presente pesquisa teve como objetivo investigar a eficácia do extrato metanólico e de várias frações, incluindo n-hexano, acetato de etila, clorofórmio e fração aquosa, obtidos do extrato metanólico de Ailanthus altissima (Mill.) Swingle, Artemisia scoparia Waldst. & Kit. e Justicia adhatoda L. usando funil de separação contra os estágios larval, pupal e adulto de C. quinquefasciatus. As larvas e pupas de C. quinquefasciatus foram expostas a várias concentrações (31,25-1000 ppm) de extrato metanólico, e suas frações por 24 horas de período de exposição. Para o bioensaio knock-down (bioensaio de impregnação de papel de filtro), diferentes concentrações do extrato metanólico e suas várias frações (ou seja, 0,0625, 0,125, 0,25, 0,5 e 1 mg / mL) foram aplicadas por um período de exposição de 1 hora. Os resultados foram analisados ​​estatisticamente usando desvio padrão, análise Probit e regressão linear. Os valores de R2 de larvas, pupas e adultos variaram de 0,4 a 0,99. Os valores de LC50 (concentração que causa 50% de mortalidade) para larvas de terceiro estádio tardio após 24 horas de período de exposição variaram de 93-1856,7 ppm, enquanto os valores de LC90 variaram de 424-7635,5ppm. Os valores de LC50 para pupas variaram de 1326,7-6818,4 ppm e os valores de LC90 variaram de 3667,3-17427,9 ppm, respectivamente. O KDT50 variou de 0,30 a 2,8% e os valores de KDT90 variaram de 1,2 a 110,8%, respectivamente. Por fim, a espécie J. adhatoda pôde ser eficaz para controlar populações de mosquitos vetores.


Subject(s)
Animals , Culex , Insecticides/pharmacology , Anopheles , Plant Extracts/pharmacology , Plant Leaves , Mosquito Vectors , Larva
3.
Braz. j. biol ; 83: 1-9, 2023. map, ilus, tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1468870

ABSTRACT

The present study was conducted to evaluate the diversity, distribution (C) and relative abundance (RA) of the mosquito fauna (Diptera: Culicidae) of Malakand and Dir Lower, Pakistan. Collection of specimens (n = 1087) was made during September 2018 to July 2019 at six different habitats including freshwater bodies, rice fields, animal sheds, indoors, drains and sewage waters. Specimens were collected through light traps, pyrethrum spray, aspirators and nets and subsequently killed, preserved and then arranged in entomological boxes for identification. Three genera were identified namely Culex, Anopheles and Aedes. A total of fourteen species were identified namely: Cx. quinquefasciatus (Say, 1823), An. stephensi (Liston, 1901), Cx. tritaeniorhynchus (Giles, 1901), Ae. vittatus (Bigot, 1861), An. maculatus (Theobald, 1901), An. fluviatilis (James, 1902), Cx. vishnui (Theobald, 1901), Ae. aegypti (Linnaeus, 1762) An. subpictus (Grassi, 1899), An. dthali (Patton, 1905), An. culicifascies (Giles, 1901), An. pallidus (Theobald, 1901), Ae. albopictus (Skuse, 1894) and An. annularis (van der Wulp, 1884). Cx. quinquefasciatus was found constantly distributed in the study area with RA = 16.5% and C = 100%. An. annularis was found as a satellite species, sporadically distributed in the study area having RA = 0.9% and C = 17%. Diversity indices of mosquitoes in the studied habitats were found as, Shannon-Wiener Index (2.415), Simpson Index (9.919), Fisher's Index (2.269) and Margalef's Index (1.859). A statistically significant difference was recorded in mosquito diversity in the six habitats (Kruskal-Wallis, chi-squared, H = 17.5, df = 5, P = 0.003 at α = 0.05). The present study encompasses [...].


O presente estudo foi conduzido para avaliar a diversidade, distribuição (C) e abundância relativa (RA) da fauna de mosquitos (Diptera: Culicidae) de Malakand e Dir Lower, Paquistão. A coleta de espécimes (n = 1087) foi feita durante o período de setembro de 2018 a julho de 2019 em seis habitats diferentes, incluindo corpos d’água, campos de arroz, galpões de animais, ambientes internos, ralos e águas residuais. Os espécimes foram coletados por meio de armadilhas luminosas, spray de piretro, aspiradores e redes e posteriormente mortos, preservados e depois dispostos em caixas entomológicas para identificação. Três gêneros foram identificados, nomeadamente Culex, Anopheles e Aedes. Um total de 14 espécies foi identificado, a saber: Cx. quinquefasciatus (Say, 1823), An. stephensi (Liston, 1901), Cx. tritaeniorhynchus (Giles, 1901), Ae. vittatus (Bigot, 1861), An. maculatus (Theobald, 1901), An. fluviatilis (James, 1902), Cx. vishnui (Theobald, 1901), Ae. aegypti (Linnaeus, 1762), An. subpictus (Grassi, 1899), An. dthali (Patton, 1905), An. culicifascies (Giles, 1901), An. pallidus (Theobald, 1901), Ae. albopictus (Skuse, 1894) e An. annularis (Van der Wulp, 1884). Cx. quinquefasciatus foi encontrado constantemente distribuído na área de estudo com AR = 16,5% e C = 100%. A. annularis foi encontrada como espécie satélite, distribuída esporadicamente na área de estudo com RA = 0,9% e C = 17%. Os índices de diversidade de mosquitos nos habitats estudados foram encontrados como índice de Shannon-Wiener (2,415), índice de Simpson (9,919), índice de Fisher (2,269) e índice de Margalef (1,859). Uma diferença estatisticamente significativa foi registrada na diversidade de mosquitos nos seis habitats (Kruskal-Wallis, qui-quadrado, H = 17,5, df = 5, P = 0,003 em α = 0,05). O presente estudo abrange a fauna de mosquitos de Malakand, Paquistão, com respeito à diversidade, abundância relativa e distribuição em [...].


Subject(s)
Animals , Aedes/classification , Anopheles/classification , Biodiversity , Culex/classification , Culicidae
4.
J. Health Biol. Sci. (Online) ; 10(1): 1-15, 01/jan./2022. tab, ilus
Article in Portuguese | LILACS | ID: biblio-1411686

ABSTRACT

Objetivos: Realizar um levantamento das contribuições científicas produzidas entre 2017 e 2021 acerca do efeito larvicida de óleos essenciais e extratos vegetais no controle de Aedes spp, Anopheles spp e Culex spp. Métodos: de setembro a outubro de 2022, foi realizado um levantamento de artigos científicos publicados entre os anos de 2017 e 2021, nas bases de dados Portal Periódicos Capes, Scielo, Science Direct e Scopus. Foram utilizados os descritores "larvicide", "essential oil" e "plant extracts" com a interposição do operador boleano "AND". Resultados: inicialmente, foram obtidos 246 artigos, dos quais 110 foram excluídos (68 não estavam disponíveis na íntegra e 42 apareceram em mais de uma base de dados). Dos 136 artigos restantes, 36 foram excluídos por não terem realizado ensaio larvicida. Dos 100 artigos remanescentes, 63 foram excluídos por não mencionarem valores de CL50, enquanto 3 não especificaram a estrutura vegetal de obtenção dos produtos naturais, restando, portanto, 34 artigos para análise. Foram utilizadas 57 espécies vegetais para a obtenção dos produtos vegetais utilizados contra larvas de Aedes spp; 11 espécies nos ensaios contra Anopheles spp, e 36 espécies nos ensaios contra Culex spp. Os óleos essenciais predominaram nos ensaios contra Aedes spp, enquanto os extratos, contra Anopheles spp. A maior parte dos produtos testados exibiu CL50 < 100 ppm. Conclusão: a atividade larvicida demonstrada por uma grande variedade de extratos vegetais e óleos essenciais representa uma alternativa promissora ao tradicional controle químico feito à base de inseticidas sintéticos em programas de manejo integrado de vetores.


Objectives: Conduct a survey of the scientific contributions produced between 2017 and 2021 on the larvicidal effect of essential oils and plant extracts in the control of Aedes spp, Anopheles spp, and Culex spp. Methods: from September to October 2022, a survey was carried out of scientific articles published between 2017 and 2021 in the Portal Periódicos Capes, Scielo, Science Direct, and Scopus databases. The descriptors "larvicide", "essential oil" and "plant extracts" were used with the Boolean operator "AND". Results: initially, 246 articles were obtained, of which 110 were excluded (68 were not available, and 42 appeared in more than one database). Of the remaining 136 articles, 36 were excluded because they did not perform a larvicide assay. Of the 100 remaining articles, 63 were excluded for not mentioning LC50 values, while three did not specify the plant structure for obtaining natural products, thus leaving 34 articles for analysis. A total of 57 plant species were used to obtain plant products used against Aedes spp larvae; 11 species in the tests against Anopheles spp, and 36 species in the tests against Culex spp. Essential oils predominated in the tests against Aedes spp, while extracts against Anopheles spp. Most of the products tested exhibited an LC50 < 100 ppm. Conclusion: the larvicidal activity demonstrated by a wide variety of plant extracts and essential oils represents a promising alternative to traditional chemical control based on synthetic insecticides in integrated vector management programs.


Subject(s)
Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Aedes/drug effects , Culex/drug effects , Larva/drug effects , Anopheles/drug effects , Larvicides , Biological Control Agents/pharmacology
5.
Bol. malariol. salud ambient ; 62(2): 190-201, 2022. tab, graf
Article in Spanish | LILACS, LIVECS | ID: biblio-1379273

ABSTRACT

Las comunidades vegetales en la zona de Tingo María, Perú, se encuentran sometidas a los efectos del cambio climático, generando modificaciones en su biodiversidad, impactando su ecosistema. Por otra parte, se ha referido que actividades que ocasionan perturbación de bosques tropicales pueden favorecer la persistencia de vectores de enfermedades metaxénicas como la malaria, la cual representa un problema de salud pública por la alta tasa de morbimortalidad en la región. Se realizó un estudio descriptivo para evaluar los rasgos funcionales del bosque perturbado de Tingo María, observando que la especie vegetal Parkia panurensis presentó mayor promedio en altura total; 47% de las especies presentaron una densidad básica alta de árboles en pie; la familia Euphorbiaceae y la especie Senefeldera inclinata presentaron el valor más alto de biomasa, mientras que Micropholis guyanensis y Pierre Subsp. Guyanensis mostraron el mayor porcentaje y cobertura de copa, respectivamente; Asimismo, Pseudopiptadenia suaveolens presentó la mayor longitud de copa, Eugenia egensis mostró mayor diámetro y Senefeldera inclinata tuvo mejor índice de valor de importancia. Además, se demostró alta circulación de vectores de malaria en la zona, siendo An. Pseudopunctipennis, An. Benarrochi, An. Darling y An. Evansae los más frecuentes, mientras que los géneros de insectos más comunes resultaron ser Anófeles, Aedes, Coqueletilia y Cúlex. Los rasgos funcionales de las especies vegetales les han permitido adaptarse a las condiciones adversas, no obstante, la presencia de abundantes vectores de malaria, hace necesario implementar estrategias de impacto ambiental, que reduzcan el riesgo de malaria en la región(AU)


Plant communities in the area of Tingo María, Peru, are subject to the effects of climate change, generating modifications in their biodiversity, impacting their ecosystem. On the other hand, it has been reported that activities that cause disturbance of tropical forests can favor the persistence of vectors of metaxenic diseases such as malaria, which represents a public health problem due to the high rate of morbidity and mortality in the region. A descriptive study was carried out to evaluate the functional traits of the disturbed forest of Tingo María, observing that the plant species Parkia panurensis presented a higher average total height; 47% of the species presented a high basic density of standing trees; the Euphorbiaceae family and the species Senefeldera inclinata presented the highest biomass value, while Micropholis guyanensis and Pierre Subsp. Guyanensis showed the highest percentage and crown cover, respectively; Likewise, Pseudopiptadenia suaveolens had the longest crown length, Eugenia egensis had the largest diameter and Senefeldera inclinata had the best importance value index. In addition, high circulation of malaria vectors was demonstrated in the area, being An. pseudopunctipennis, An. benarrochi, An. darling and An. evansae the most frequent, while the most common insect genera were Anopheles, Aedes, Coqueletilia and Culex. The functional traits of plant species have allowed them to adapt themselves to adverse conditions, however, the presence of abundant malaria vectors makes it necessary to implement environmental impact strategies that reduce the risk of malaria in the region(AU)


Subject(s)
Plasmodium , Disease Vectors , Malaria , Anopheles , Climate Change , Forests , Public Health , Ecosystem , Biodiversity
6.
Braz. j. biol ; 82: e241338, 2022. tab
Article in English | LILACS, VETINDEX | ID: biblio-1278470

ABSTRACT

Mosquito-borne diseases result in the loss of life and economy, primarily in subtropical and tropical countries, and the emerging resistance to insecticides is increasing this threat. Botanical insecticides are promising substitutes for synthetic insecticides. This study evaluated the larvicidal and growth index of Culex pipiens of four solvent extracts of Terminalia chebula, Aloe perryi, and Peganum harmala against Cx. pipiens. None of the 12 extracts exhibited larvicidal potential against third instars except the ethyl acetate extract of P. harmala. After 24 h of exposure, the LC50 value was 314.88 ppm, and the LC90 value was 464.19 ppm. At 320 ppm, the hatchability was 25.83%, and it resulted in 100% mortality. In addition, the eggs treated with the EtOAc extract of P. Harmala exhibited a long larval period compared with the control. The larval period continued for 12 days, and the pupal period took three days in the treatment groups. The growth index data also exhibited a decrease (0.00­7.53) in the treated groups compare with 8.5 in the control. The transformation of eggs into adults decreased with increasing concentrations. This paper is the first report on the development and growth index of Cx. pipiens potential using P. harmala seeds.


As doenças transmitidas por mosquitos resultam na perda de vidas e economia, principalmente em países subtropicais e tropicais, e a resistência emergente aos inseticidas está aumentando essa ameaça. Os inseticidas botânicos são substitutos promissores dos inseticidas sintéticos. Este estudo avaliou o índice larvicida e de crescimento de Culex pipiens de quatro extratos solventes de Terminalia chebula, Aloe perryi e Peganum harmala contra Cx. pipiens. Nenhum dos 12 extratos exibiu potencial larvicida contra o terceiro ínstar, exceto o extrato de acetato de etila de P. harmala. Após 24 horas de exposição, o valor LC50 era 314,88 ppm e o valor LC90 era 464,19 ppm. A 320 ppm, a eclodibilidade foi de 25,83% e resultou em 100% de mortalidade. Além disso, os ovos tratados com o extrato de EtOAc de P. harmala exibiram um longo período larval em comparação com o controle. O período larval continuou por 12 dias, e o período pupal durou três dias nos grupos de tratamento. Os dados do índice de crescimento também exibiram uma diminuição (0,00-7,53) nos grupos tratados em comparação com 8,5 no controle. A transformação de ovos em adultos diminuiu com o aumento das concentrações. Este artigo é o primeiro relatório sobre o índice de desenvolvimento e crescimento de Cx. potencial de pipiens usando sementes de P. harmala.


Subject(s)
Animals , Aedes , Culex , Peganum , Insecticides , Anopheles , Seeds , Plant Extracts/pharmacology , Larva
7.
Bol. malariol. salud ambient ; 61(4): 565-587, dic. 2021. ilus., tab.
Article in Spanish | LILACS, LIVECS | ID: biblio-1392424

ABSTRACT

Este estudio forma parte de la primera etapa de una serie de estudios sobre la ecología, biodiversidad y biogeografía de los mosquitos de la familia Culicidae de Venezuela, principalmente en Bolívar y Delta Amacuro. El objetivo del estudio fue caracterizar la composición de especies, la abundancia y la biodiversidad de mosquitos (Diptera; Culicidae) en el municipio Gran Sabana del estado Bolívar. Las capturas de mosquitos adultos se realizaron con aspiradores bucales mediante capturas por atracción al cebo humano y con trampas de luz negra. Se determinó la riqueza de especies, su abundancia relativa e índices ecológicos de diversidad Shannon-Wiener (H'), equidad de Simpson (E) y dominancia-D, del área general de estudio y sitios o comunidades de muestreo. Los resultados del estudio, generaron el registro de 7.860 ejemplares adultos de Culicidae identificados a nivel de especie, pertenecientes a 69 especies y 17 géneros, de ellos 7.797 (99,19%) fueron hembras adultas capturadas picando o con trampas de luz y 63 (0,81%) fueron machos capturados con trampas de luz. El 16,6% (1.297) de las hembras fue atraído por trampas de luz y el 83,4% (6.500) por cebo humano. Entre las especies más abundantes del estudio están: Culex quinquefasciatus (26,67 %), Anopheles peryassui (12,32 %), Aedes aegypti (11,87 %), Coquilletidia juxtamansonia (8,28 %), Anopheles braziliensis (6,97 %) Anopheles triannulatus s.l. (6,39 %), Coquilletidia nigricans (2,88 %), Coquilletidia venezuelensis (2,51 %) y Anopheles albitarsis s.l. (2,44 %), las cuales en conjunto representan 80,33 % del total de adultos capturado. Se discuten algunos aspectos sobre su ecología, importancia médica y el riesgo epidemiológico que representan para el país algunas especies reportadas. La diversidad de Shannon-Wiener (H') del área general de estudio fue de 2,665, la equidad de Simpson (E) fue igual a 0,8787222 y la dominancia (D) fue de 0,1213. El mayor índice de diversidad (Shannon-Wiener) ocurrió en Chiririka (2,675), seguido de Betania (2,409), Santa Elena Capital (2,354), Manak-Krü (2,203) y Waramasén (2,181). En cuanto a la riqueza de especies por localidad, las comunidades con mayor riqueza de especies fueron: Santa Elena (Capital), Waramasén y Chiririka con 50, 35 y 30 especies respectivamente, seguidas por San Antonio del Morichal con 23 y Kinok-Pon Parú, con 22 especies(AU)


This is the first part of a series of studies related to biodiversity, ecological and biogeographic aspects of the mosquitoes of Culicidae family in Venezuela. The objective of this study was the ecological characterization of species composition, diversity and abundance of Culicidae mosquitoes (Diptera: Culicidae) in the Gran Sabana Municipality, Bolívar State. Mosquitoes were captured in adult collections, with aspirators on human landing catches and with black light traps. A total of 7.860 adult's mosquitoes were collected and 69 species and 17 genera of Culicidae were identified. A total of 7.797 mosquitoes (99.19%) were females and 63 (0,81%) were males. Some 16,6 % (1.297) of females mosquitoes were attracted to the light traps and 83,4% (6.500) to human bait. The most abundant species in adult stage were: Culex quinquefasciatus (26,67%), Anopheles peryassui (12,32 %), Aedes aegypti (11,87 %), Coquilletidia juxtamansonia (8,28%), Anopheles braziliensis (6,97%), Anopheles triannulatus s.l. (6,39%), Coquilletidia nigricans (2,88%), Coquilletidia venezuelensis (2,51%) and Anopheles albitarsis s.l. (2,44%). Their medical importance of some mosquito species is commented, and some ecological and epidemiological aspects of the mosquito reported are discussed. The diversity index (Shannon-Wiener) of the estudy area was 2,665, the Simpson equity index was 0, 8787222 and the index of dominance was 0, 1213. The higher diversity index was registered in Chiririka (2,675), Betania (2,409), Santa Elena Capital (2,354), Manak-Krü (2,203) and Waramasén (2,181). The higher species richness was registered in Santa Elena (50 species), Waramasén (35 species), Chiririka (30 species), San Antonio del Morichal (23 species) and Kinok-Pon Parú (22 species) (AU)


Subject(s)
Animals , Aedes , Culex , Biodiversity , Anopheles , Culicidae , Culicidae/classification , Venezuela , Diptera , Mosquito Vectors/classification
9.
Mem. Inst. Oswaldo Cruz ; 116: e200497, 2021. graf
Article in English | LILACS | ID: biblio-1154873

ABSTRACT

BACKGROUND Flight tones play important roles in mosquito reproduction. Several mosquito species utilise flight tones for mate localisation and attraction. Typically, the female wingbeat frequency (WBF) is lower than males, and stereotypic acoustic behaviors are instrumental for successful copulation. Mosquito WBFs are usually an important species characteristic, with female flight tones used as male attractants in surveillance traps for species identification. Anopheles darlingi is an important Latin American malaria vector, but we know little about its mating behaviors. OBJECTIVES We characterised An. darlingi WBFs and examined male acoustic responses to immobilised females. METHODS Tethered and free flying male and female An. darlingi were recorded individually to determine their WBF distributions. Male-female acoustic interactions were analysed using tethered females and free flying males. FINDINGS Contrary to most mosquito species, An. darlingi females are smaller than males. However, the male's WBF is ~1.5 times higher than the females, a common ratio in species with larger females. When in proximity to a female, males displayed rapid frequency modulations that decreased upon genitalia engagement. Tethered females also modulated their frequency upon male approach, being distinct if the interaction ended in copulation or only contact. MAIN CONCLUSIONS This is the first report of An. darlingi flight acoustics, showing that its precopulatory acoustics are similar to other mosquitoes despite the uncommon male:female size ratio, suggesting that WBF ratios are common communication strategies rather than a physical constraint imposed by size.


Subject(s)
Animals , Male , Female , Mosquito Vectors , Malaria/transmission , Anopheles , Reproduction
10.
Mem. Inst. Oswaldo Cruz ; 116: e210064, 2021. graf
Article in English | LILACS | ID: biblio-1279459

ABSTRACT

Unforeseen Plasmodium infections in the Atlantic Forest of Brazilian Extra-Amazonian region could jeopardise malaria elimination. A human malaria case was registered in Três Forquilhas, in the Atlantic Forest biome of Rio Grande do Sul, after a 45 years' time-lapsed without any malaria autochthonous notification in this southern Brazilian state. This finding represents the expansion of the malaria distribution areas in Brazil and the southernmost human malaria case record in South America in this decade. The coexistence of the bromeliad-breeding vector Anopheles (Kerteszia) cruzii and non-human primates in the Atlantic Forest regularly visited by the patient claimed for the zoonotic origin of this infection. The reemergence of Atlantic Forest human malaria in Rio Grande do Sul was also discussed.


Subject(s)
Animals , Malaria/epidemiology , Anopheles , Brazil/epidemiology , Forests , Mosquito Vectors
11.
Rev. Soc. Bras. Med. Trop ; 54: e08352020, 2021. graf
Article in English | LILACS | ID: biblio-1288107

ABSTRACT

Abstract INTRODUCTION: Bioprospection of plant products is used to discover new insecticides. METHODS: The larvicidal activity of ethanolic extract and triterpene (tingenone B) from the bark of Maytenus guianensis and their effect on pupation and emergence were evaluated against Aedes aegypti. RESULTS: Crude extract LC50 was 11.3 ppm and caused ejection of the larvae intestine; tingenone B LC50 was 14.8 ppm. Pupation was reduced by 20% and 10%, respectively; however, the emergence was not affected. CONCLUSIONS: The crude bark extract exhibited a higher larvicidal effect against the vector.


Subject(s)
Aedes , Celastraceae , Maytenus , Insecticides/pharmacology , Anopheles , Plant Extracts/pharmacology , Plant Leaves , Mosquito Vectors , Larva
12.
Rev. Soc. Bras. Med. Trop ; 54: e00922020, 2021. tab, graf
Article in English | SES-SP, ColecionaSUS, LILACS | ID: biblio-1143892

ABSTRACT

Abstract INTRODUCTION: Despite their widespread usage, synthetic insecticides and larvicides are harmful for controlling disease-causing mosquitoes owing to the development of resistance. The leaves of Eugenia astringens, Myrrhinium atropurpureum, and Neomitranthes obscura were collected from Marambaia and Grumari restingas. The safety and larvicidal efficacy of their extracts were tested against Aedes (Stegomyia) aegypti L. and Simulium (Chirostilbia) pertinax Kollar. METHODS: The dry leaves were subjected to static maceration extraction using 90% methanol. A. aegypti and S. pertinax larvae were exposed to 7.5, 12.5, and 25.0 µL/mL of the extracts (n= 30). The larvicidal activity after 24 h and 48 h, and the mortality, were determined. The median lethal concentration (CL50) was estimated by a Finney's probit model. RESULTS: M. atropurpureum and E. astringens extracts exhibited the strongest larvicidal effects against A. aegypti. M. atropurpureum extracts (25 µL/mL) caused mortalities of over 50% and 100% after 24 h and 48 h, respectively (CL50 = 11.10 and 9.68 ppm, respectively). E. astringens extracts (25 µL/mL) caused mortalities of 50% and 63.33% after 24 h and 48 h, respectively. High concentrations of N. obscura extracts induced a maximum mortality of 46.66% in A. aegypti larvae after 48 h (CL50= 25 ppm). The larvae of S. pertinax showed 100% mortality following exposure to all the plant extracts at all the tested concentrations after 24 h. CONCLUSIONS: The extracts of M. atropurpuerum exhibited the strongest larvicidal activity against A. aegypti. The larvae of S. pertinax were sensitive to all the extracts at all the tested concentrations.


Subject(s)
Animals , Simuliidae , Aedes , Culex , Myrtaceae , Insecticides/pharmacology , Anopheles , Plant Extracts/pharmacology , Plant Leaves , Larva
13.
Rev. med. vet. zoot ; 67(3): 253-261, sep.-dic. 2020. tab
Article in Spanish | LILACS, COLNAL | ID: biblio-1251920

ABSTRACT

RESUMEN Objetivo: determinar la frecuencia de dirofilariosis en caninos de la localidad 3 de la ciudad de Cartagena. Materiales y métodos: estudio correlacional de corte transversal. Se tomaron muestras de sangre de 128 perros con el consentimiento previo e informado de sus dueños. Se registró la información sociodemográfica y los síntomas. A las muestras se les realizo observación directa, extendido de sangre periferia coloreado con Wright y la técnica de Knott. Resultados: se estableció que 19,5% de los perros se encontraban parasitados con Dirofilaria sp. Los signos sugestivos de dirofilariosis más frecuentes fueron pérdida de peso y disminución del apetito (10,9% cada uno). El 76% de los caninos eran mestizos. Conclusiones: la frecuencia de dirofilariosis se concentra principalmente en barrios de escasos recursos, los síntomas identificados son sugestivos de una dirofilariosis canina.


ABSTRACT Objective: to determine the frequency of dirofilariosis in canines from locality 3 of Cartagena city. Materials and methods: cross-sectional correlational study. Blood samples were taken for 128 dogs prior informed consent by their owners. Sociodemographic information and symptoms were registered. The samples have been analyzed using direct examination, Wright stained blood smear and Knott technique. Results: it was established that 19.5% of dogs were parasitized by Dirofilaria sp. Most common signs suggestive of Dirofilariosis were weight loss, and decreased appetite (10.9% each). 76% were mixed race dogs. Conclusions: the frequency of dirofilariosis focused on lower income neighborhoods. The identified symptoms are suggestive of canine dirofilariasis.


Subject(s)
Animals , Dogs , Signs and Symptoms , Blood , Prevalence , Dirofilaria immitis , Dogs , Pets , Cross-Sectional Studies , Tropical Ecosystem , Aedes , Culex , Anopheles , Culicidae
14.
Salud pública Méx ; 62(4): 379-387, jul.-ago. 2020. tab, graf
Article in English | LILACS | ID: biblio-1377329

ABSTRACT

Abstract: Objective: To determine the species distribution, abundance, and diversity of culicids in the Yucatan Peninsula (YP); their potential distribution, using ecological niche modeling (ENM), and the risk of contact with urban and rural populations. Materials and methods: A cross-sectional study was carried out through the YP. The diversity of species was determined with the Shannon index. The potential distribution of the culicids was determined through the ENM, as well as the risk of urban and rural populations through contact with vectors. Results: A total of 10 699 specimens, 15 genera and 52 species were registered. Campeche and the Biosphere Reserve of Calakmul exhibited the highest diversity. Conclusions: The ENM predict a high suitability in all the YP of Ae. aegypti, An. albimanus, An. pseudopuntipennis, Cx. coronator, and Cx. quinquefasciatus. The vector species that exhibited the highest risk of contact in the YP were Cx. quinquefasciatus, Ae. aegypti and Ae. albopictus.


Resumen: Objetivo: Determinar la distribución, abundancia y di versidad de los culícidos de la Península de Yucatán (PY), su distribución potencial utilizando modelos de nicho ecológico (MNE) y el riesgo de contacto con poblaciones urbanas y rurales. Material y métodos: Se realizó un estudio transversal. La diversidad fue determinada por el índice de Shannon. La distribución potencial de los culícidos se deter minó a través de MNE, así como el riesgo de las poblaciones urbanas y rurales al contacto con los vectores. Resultados: En total, se registraron 10 699 especímenes, 15 géneros y 52 especies. Campeche y la Reserva de la Biosfera de Calakmul presentaron la mayor diversidad. Conclusiones: El MNE predice una alta idoneidad en toda la PY para Ae. aegypti, An. albimanus, An. pseudopuntipennis, Cx. coronador y Cx. quinque fasciatus. Las especies de vectores que presentaron el mayor riesgo de contacto en la PY fueron Cx. quinquefasciatus, Ae. aegypti y Ae. albopictus.


Subject(s)
Animals , Biodiversity , Mosquito Vectors , Culicidae , Cross-Sectional Studies , Population Density , Aedes , Culex , Insect Vectors , Anopheles , Mexico
15.
Salud pública Méx ; 62(4): 388-401, jul.-ago. 2020. tab, graf
Article in English | LILACS | ID: biblio-1377330

ABSTRACT

Abstract: Objective: To determine the abundance and geographic distribution of the main malaria vectors, which are influenced by habitat characteristics and ecological factors that directly impact adult density and the dynamics of malaria transmission in Mexico. Materials and methods: Samples of larvae were collected from 19 states in Mexico. Each larval habitat was characterized in situ determining the following parameters: water depth, turbidity, percentage of vegetation cover, amount of detritus, presence of algae, light intensity, type of vegetation, amount of predators, habitat stability, altitude, and hydrologic type. Results: A total of 21 687 larvae corresponding to 13 anopheline species were obtained from 149 aquatic habitats. The most abundant species were Anopheles pseudopunctipennis (52.91%), An. albimanus (39.14%) and An. franciscanus (5.29%). The multiple logistic regression analysis showed a negative association between An. pseudopunctipennis and water turbidity (ß=-1.342; Wald=6.122; p=0.013) and the amount of detritus (ß=-2.206; Wald=3.642; p=0.050). While in An. albimanus, there was a significant positive association with water turbidity (ß=1.344; Wald=4.256; p=0.039), a negative correlation was found with the altitude (ß=-3.445; Wald=5.407; p=0.020). The highest mosquito species diversity index was found in Chiapas (Fisher's α=1.20) and the lowest diversity in Chihuahua (Fisher's α=0.26). The greatest richness was found in streams (n=11). Conclusions: The two most abundant species were: An. albimanus and An. pseudopunctipennis. Detailed knowledge of the distribution and characteristics of their larval habitats will be useful for the effective implementation of control strategies in Mexico.


Resumen Objetivo: Determinar la abundancia y la distribución geográfica de los principales vectores de la malaria, las cuales están influenciadas por las características del hábitat y los factores ecológicos que afectan directamente la densidad de los adultos y la dinámica de la transmisión de la malaria en México. Material y métodos: Se obtuvieron muestras de larvas de 19 estados de México. Cada hábitat larvario se caracterizó in situ determinando los siguientes parámetros: profundidad del agua, turbidez, porcentaje de cobertura vegetal, cantidad de detritus, presencia de algas, intensidad de luz, tipo de vegetación, cantidad de depredadores, estabilidad del hábitat, altitud y tipo hidrológico. Resultados: Se identificaron un total de 21 687 larvas pertenecientes a 13 especies de anofelinos, de 149 hábitats acuáticos. Las tres especies más abundantes fueron Anopheles pseudopunctipennis (52.91%), An. albimanus (39.14%) y An. franciscanus (5.29%). El análisis de regresión logística múltiple mostró una asociación negativa para An. pseudopunctipennis y la turbidez del agua (ß=-1.342; Wald= 6.122; p=0.013) y la cantidad de detritus (ß=-2.206; Wald= 3.642; p=0.050). Para An. albimanus se encontró una asociación positiva significativa con la turbidez del agua (ß=1.344; Wald= 4.256; p=0.039) y una correlación negativa con la altitud (ß=-3.445; Wald=5.407; p=0.020). El índice de diversidad más alto se encontró en Chiapas (α de Fisher=1.20) y la diversidad más baja en Chihuahua (α de Fisher=0.26). La mayor riqueza se encontró en los arroyos (n=11). Conclusiones: Las dos especies más abundantes fueron An. albimanus y An. pseudopunctipennis. El conocimiento detallado de la distribución y características de sus hábitats larvales será útil para la implementación efectiva de las estrategias de control en México.


Subject(s)
Animals , Ecosystem , Mosquito Vectors , Anopheles , Species Specificity , Water/parasitology , Regression Analysis , Population Density , Larva , Malaria/transmission , Mexico
16.
Article in Spanish | LILACS, BDNPAR | ID: biblio-1293251

ABSTRACT

Las mutaciones KDR en el gen del canal del sodio (VGSC) han sido ya detectadas en al menos 13 especies de mosquitos Anopheles en su mayoría especies de África, pero aún resta por determinar los cebadores específicos para la detección en especies de Latinoamérica. En nuestro país la especie Anopheles darlingi es el vector principal de la malaria, y el A. albitarsis, el vector secundario. Se emplearon muestras de mosquitos Anoheles de las especies A. strodei, A. albitarsis, A. fluminensis, A. evansae, A. nuneztovari, A. nyssorhynchela lutzi y A. oswaldoi capturadas en los departamentos de Caaguazú y Alto Paraná en Paraguay. Para la amplificación y secuenciación se usaron cebadores reportados para el gen VGSC de A. albimanus en Guatemala, que resultaron ser específicos solo para la especie A. strodei. La secuencia revela el codón TTA que codifica para una Leucina como la secuencia TTG, reportada para la versión susceptible en la posición L1014. El fragmento amplificado es de aproximadamente 225 pares de bases. A nuestro entender, esta es la primera caracterización del gen VGSC en mosquitos Anopheles del Paraguay y para la especie A. strodei


KDR mutations in the sodium channel gene (VGSC) have already been detected in at least 13 species of Anopheles mosquitoes, mostly African species, but the molecular techniques for detection in Latin American species have yet to be determined. In our country, Anopheles darlingi species is the main vector of Malaria, and A. albitarsis, the secondary vector. We used samples of Anoheles from the species A. strodei, A. albitarsis, A. fluminensis, A. evansae, A. nuneztovari, A. nyssorhynchela lutzi and A. oswaldoi collected at the departments of Caaguazú and Alto Paraná in Paraguay. For the amplification and sequentiation, primers reported for the VGSC gen of A. strodei in Guatemala were used and were specific only for A. strode in this case. The sequence revealed the TTA codon that codifies for a leucine as the TTG sequence, reported for the susceptible version at position L1014. The amplified fragment is approximately 225 base pairs. To our knowledge, this is the first characterization of the VGSC gene in Anopheles mosquitoes in Paraguay and for the species A. strodei


Subject(s)
Animals , Polymerase Chain Reaction , Anopheles , Sodium Channels , Mosquito Vectors
17.
Bol. malariol. salud ambient ; 60(1): 101-108, jul 2020. ilus., tab.
Article in Spanish | LILACS, LIVECS | ID: biblio-1509534

ABSTRACT

La malaria en Venezuela es altamente heterogénea y focalizada. En 2016 se reportaron más de 242 mil casos nuevos en el país, de los cuales 73% provenían del estado Bolívar, 42% del municipio Sifontes y 29% de la parroquia San Isidro. Entre octubre 2016 y mayo 2017 se realizó en la parroquia San Isidro un estudio exploratorio, con el fin de establecer una línea basal entomológica en malaria que permitiera la evaluación posterior de Rociamientos Intradomiciliarios de Insecticida y Mosquiteros Tratados con insecticida de Larga Duracion.Las capturas de mosquitos adultos con Trampas Mosquito Magnet Independence™, atrayente humano y en reposo pre-hematofágico, permitieron determinar que en esta parroquia, hay por lo menos tres especies de anofelinos con actividad hematofágica antropofílica, An. darlingi, An. albitarsis s.l. y An. nuneztovari s.l., cuyos hábitos de reposo y actividad de picada fueron descritos. Asimismo, el muestreo de hábitats larvales permitió determinar que las lagunas residuales de la actividad minera son los más importantes y que An. albitarsis s.l. y An. triannulatus s.l. son las especies de mayor prevalencia en estos hábitats. Estos hallazgos permiten actualizar la data entomológica de este foco caliente de malaria y sientan las bases para la evaluación y seguimiento de las medidas de control de vectores implementadas(AU)


Malaria in Venezuela is highly heterogeneous and focused. In 2016, more than 242,000 malaria cases were reported in the country, from which 73% came from Bolivar state, 42% from Sifontes municipality and 29% from the San Isidro parish. Between October 2016 and May 2017, an exploratory study was carried out in order to establishing an entomologic baseline that would allow posterior evaluations of indoors insecticide spraying and long lasting insecticidal nets. Adults captures with Mosquito Magnet Independence™ traps, human landing, and pre-feedingresting habits allowed to determine that in San Isidro there are at least three anopheline species with significant anthropophilic activity: An darlingi, An. albitarsis s.l. and An. nuneztovari s.l. Resting habits and biting activities were described for the three species. Likewise, larval sampling were carried out which allowed to identify that abandoned gold mine dugouts are the most important habitatsfor these species. Particularly, An. albitarsis s.l. and An. triannulatus s.l. were the most prevalent anophelines colonizing these breeding sites. Our results update entomologic data of this malaria hot spot area and establish the baseline for further evaluations ofthe vector control measures implemented(AU)


Subject(s)
Animals , Entomology/methods , Malaria/prevention & control , Venezuela , Mosquito Vectors , Anopheles
18.
Rev. Soc. Bras. Med. Trop ; 53: e20190018, 2020. graf
Article in English | LILACS | ID: biblio-1092184

ABSTRACT

Abstract INTRODUCTION: The larvicidal potential of Saussurea costus (Falc.) Lipsch. was studied against the early 4th instar larvae of Anopheles stephensi Liston., Aedes aegypti Linn.,and Culex quinquefasciatus Say. because of the emergence of mosquito resistance to conventional synthetic insecticides. METHODS: At concentrations of 12.5-200 ppm, larvicidal activities were studied under laboratory conditions. RESULTS: After 24 h of exposure, the methanol extract of the roots recorded the highest larvicidal activity against An. stephensi, with LC50 and LC90values of 7.96 and 34.39 ppm, respectively. CONCLUSIONS: We are developing potent larvicidal compound(s) from S. costus for controlling the mosquito larval population.


Subject(s)
Animals , Plant Extracts/pharmacology , Aedes/drug effects , Culex/drug effects , Saussurea/chemistry , Insecticides/pharmacology , Larva/drug effects , Anopheles/drug effects , Insecticides/isolation & purification
20.
Rev. Soc. Bras. Med. Trop ; 53: e20190211, 2020. tab, graf
Article in English | LILACS | ID: biblio-1057287

ABSTRACT

Abstract INTRODUCTION Anopheles stephensi is the main malaria vector in Southeast Asia. Recently, plant-sourced larvicides are attracting great interests. METHODS: The essential oil was extracted from the leaf of Cinnamomum camphora (L.), and a bioassay was conducted to determine the larvicidal efficacy. The chemical composition of the essential oil was determined by GC-MS analysis. RESULTS: The oil showed strong, dose-dependent larvicidal activities. The onset of larvicidal efficiency was rapid. The LC50 and LC95 were determined as 0.146% and 1.057% at 1 h, 0.031% and 0.237% at 12 h, 0.026% and 0.128% at 24 h, respectively. The oil contains 32 compounds. CONCLUSIONS The essential oil of C. camphora leaf has an excellent larvicidal potential for the control of A. stephensi.


Subject(s)
Animals , Oils, Volatile/pharmacology , Cinnamomum camphora/chemistry , Mosquito Vectors/drug effects , Insecticides/pharmacology , Larva/drug effects , Anopheles/drug effects , Biological Assay , Oils, Volatile/isolation & purification , Mosquito Vectors/classification , Insecticides/isolation & purification , Lethal Dose 50 , Anopheles/classification
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