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1.
Rev. saúde pública (Online) ; 55: 18, 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1289991

ABSTRACT

ABSTRACT OBJECTIVE: To evaluate locomotor activity in four field populations of Ae. aegypti with different insecticide resistance profiles from the state of São Paulo for two years. METHODS: This study comprised the susceptible Rockefeller strain and four populations from São Paulo, Brazil: two considered populations with "reduced susceptibility" to pyrethroids (Campinas and Marília), and two "resistant populations" (Santos and Ribeirão Preto). First, 2016 and 2017 eggs from these five populations were hatched in laboratory. Virgin females underwent experiments under laboratory conditions at 25°C, with 12:12h light/dark (LD) photoperiod; 24-hour individual activity was recorded using a locomotor activity monitor (LAM). RESULTS: In females from 2016 field populations, both resistant populations showed significant more locomotor activity than the two reduced susceptibility populations and the Rockefeller strain (p < 0.05). As for females from 2017 field populations, reduced susceptibility populations showed a significant increased locomotor activity than the Rockefeller strain, but no significant difference when compared to Santos resistant population (p > 0.05). CONCLUSIONS: Our results indicate that insecticide-resistant Ae. aegypti populations show increased locomotor activity, which may affect the transmission dynamics of their arboviruses.


Subject(s)
Humans , Animals , Female , Pyrethrins/pharmacology , Aedes , Brazil , Insecticide Resistance , Locomotion
2.
Braz. j. otorhinolaryngol. (Impr.) ; 86(5): 587-592, Sept.-Oct. 2020. tab, graf
Article in English | LILACS | ID: biblio-1132628

ABSTRACT

Abstract Introduction: This study presents the effect of cypermethrin on the cochlear function in Wistar rats post-subchronic inhalation exposure. Worldwide several pesticides are described as causing health disorders. Cypermethrin is currently one of the most commonly used, however, little is known about its harmful effects, especially related to hearing. Human studies have associated pesticides with hearing disorders, but they present limited conclusions due to the multiple factors to which the population is exposed, such as noise. Objective: Mimic human exposure to cypermethrin and to verify the effects on cochlear function. Methods: It is a subchronic inhalation animal study (6 weeks, 4 hours/day), using 36 male Wistar aged 60 day. Rats were randomly assigned into three groups: Control (12 rats exposed to inhalation of water); Positive Control for auditory lesion (12 rats administrated with 24 mg/kg intraperitoneal cisplatin); Experimental (12 rats exposed to inhalation of cypermethrin - 0.25 mg/L). Animals were evaluated by distortion product otoacoustic emissions pre- and post-exposure. Results: The frequencies of 8, 10 and 12 kHz in both ears (right p = 0.003; 0.004; 0.008 and left 0.003; 0.016; 0.005 respectively) and at frequencies 4 and 6 in the right ear (p = 0.007 and 0.015, respectively) in the animals exposed to cypermethrin resulted in reduction. Conclusion: Subchronic inhalation exposure to cypermethrin provided ototoxicity in rats.


Resumo Introdução: Este estudo apresenta o efeito da cipermetrina sobre a função coclear em ratos Wistar após exposição por inalação subcrônica. Em todo o mundo, vários pesticidas são descritos como causadores de distúrbios de saúde. A cipermetrina é atualmente um dos mais utilizados, porém pouco se conhece sobre seus efeitos deletérios, principalmente relacionados à audição. Estudos em humanos associaram pesticidas a alterações auditivas, mas apresentaram conclusões limitadas devido aos múltiplos fatores aos quais a população está exposta, como, por exemplo, o ruído. Objetivo: Mimetizar a exposição humana à cipermetrina e verificar os seus efeitos na função coclear. Método: Estudo de inalação subcrônica em animais (6 semanas, 4 horas/dia), 36 ratos machos Wistar com 60 dias. Os ratos foram distribuídos aleatoriamente em três grupos: controle (12 ratos expostos à inalação de água); controle positivo para lesão auditiva (12 ratos com administração de 24 mg/kg de cisplatina intraperitoneal); e experimental (12 ratos expostos a inalação de cipermetrina - 0,25 mg/L). Os animais foram avaliados por emissões otoacústicas por produto de distorção, pré e pós-exposição. Resultados: As frequências de 8, 10 e 12 kHz em ambas as orelhas (direita p = 0,003; 0,004; 0,008 e esquerda 0,003; 0,016; 0,005 respectivamente) e frequências 4 e 6 na orelha direita (p = 0,007 e 0,015, respectivamente) apresentaram redução nos animais expostos à cipermetrina. Conclusão: A exposição subcrônica por inalação à cipermetrina resultou em ototoxicidade em ratos.


Subject(s)
Animals , Male , Rats , Pyrethrins/toxicity , Otoacoustic Emissions, Spontaneous , Cisplatin , Rats, Wistar , Ototoxicity , Antineoplastic Agents
3.
Arq. Inst. Biol ; 87: e1132018, 2020. tab, graf
Article in English | ID: biblio-1130106

ABSTRACT

This study evaluates the effects of combinations of pyrethroids and neonicotinoids on the control of stink bugs at different stages of soybean crop development. The experiment was set up in a factorial randomized block design (4×6: 4 treatments and 6 stages) with 4 repetitions. The following treatments were tested during the V6/V7, R2, R4, R5.1, R5.5 and R 6 phenological stages: 1 ­ control (no application), 2 ­ thiamethoxam + λ-cyhalothrin, 3 ­ acetamiprid + α-cypermethrin, and 4 ­ dinotefuran + α-cypermethrin. Infestation, number of damaged seeds, number of pods, number of pods per plant, and yield (kg/ha) were evaluated. Stink bug infestations were smaller when applications commenced during the vegetative stages (V6-V8). Pod numbers and yields were highest in the dinotefuran + α-cypermethrin treatment with applications from V6/V8 to R4. The active ingredients dinotefuran + α-cypermethrin reduced stink bug populations and increased yields and could therefore be considered in integrated pest management (IPM) programs for soybean crops.(AU)


O objetivo deste trabalho foi avaliar o efeito de combinações de piretroides com neonicotinoides no controle de percevejos em diferentes estádios de desenvolvimento da cultura da soja. O delineamento experimental foi em blocos randomizados, em esquema fatorial 4×6 (4 tratamentos e 6 estádios) com 4 repetições. Os produtos utilizados foram: 1 ­ testemunha (sem aplicação), 2 ­ tiametoxam + λ-cialotrina, 3 ­ acetamiprida + α-cipermetrina, e 4 ­ dinotefuran + α-cipermetrina, e as aplicações foram realizadas a partir dos estádios fenológicos V6/V7,R2, R4, R5.1, R5.5 e R6. Avaliaram-se a infestação, número de grãos danificados, número de vagens, número de vagens por planta e produtividade (kg/ha). A infestação de percevejo foi menor quando se iniciou a aplicação precocemente nos estádios vegetativos (V6-V8).O número de vagens e produtividade foi superior no tratamento dinotefuran + α-cipermetrina nos estádios V6/V8 até R4. Os ingredientes ativos dinotefuran + α-cipermetrina apresentaram resultados positivos na redução da população de percevejo e proporcionaram incremento no rendimento de grão, podendo ser utilizado como opção em programa de manejo integrado de pragas (MIP) na cultura da soja.(AU)


Subject(s)
Soybeans , Pest Control , Cimicidae , Pyrethrins , Neonicotinoids , Fungi
4.
Rev. Soc. Bras. Med. Trop ; 53: e20200680, 2020. tab, graf
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1143869

ABSTRACT

Abstract INTRODUCTION: The use of insecticide-impregnated dog collars is a potentially useful tool for the control of visceral leishmaniasis. The objective of the present study was to perform a cost-effectiveness analysis of a program based on insecticide-impregnated collars compared to traditional visceral leishmaniasis control strategies used in Brazil. METHODS: A cost-effectiveness analysis was performed from the perspective of the Unified Health System, using data from the Visceral Leishmaniasis Control Program implemented in the municipality of Montes Claros, Minas Gerais. The direct costs of the three control strategies, which were 1) canine infection screening + sacrifice, 2) residual chemical control of the vector, and 3) insecticide-impregnated dog collars (Scalibor®), were evaluated over the two-year study period. RESULTS: The total cost of the program in the area subjected to the traditional control strategies (strategies 1 and 2; control area) was R$ 1,551,699.80, and in the area subjected to all three control strategies (intervention area), it was R$ 1,898,190.16. The collar program was considered highly cost-effective at preventing canine visceral leishmaniasis (incremental cost-effectiveness ratio of approximately R$ 578 per avoided dog sacrifice). CONCLUSIONS: These results provide support for the decision by the Brazilian Ministry of Health in 2019 to provide insecticide-impregnated collars for the control of canine visceral leishmaniasis in a pilot project.


Subject(s)
Humans , Animals , Dogs , Pyrethrins , Dog Diseases/prevention & control , Insecticides , Leishmaniasis, Visceral/prevention & control , Leishmaniasis, Visceral/veterinary , Brazil , Pilot Projects , Cost-Benefit Analysis , Nitriles
5.
Mem. Inst. Oswaldo Cruz ; 115: e200313, 2020. tab, graf
Article in English | LILACS | ID: biblio-1154867

ABSTRACT

BACKGROUND Aedes aegypti is the sole vector of urban arboviruses in French Guiana. Overtime, the species has been responsible for the transmission of viruses during yellow fever, dengue, chikungunya and Zika outbreaks. Decades of vector control have produced resistant populations to deltamethrin, the sole molecule available to control adult mosquitoes in this French Territory. OBJECTIVES Our surveillance aimed to provide public health authorities with data on insecticide resistance in Ae. aegypti populations and other species of interest in French Guiana. Monitoring resistance to the insecticide used for vector control and to other molecule is a key component to develop an insecticide resistance management plan. METHODS In 2009, we started to monitor resistance phenotypes to deltamethrin and target-site mechanisms in Ae. aegypti populations across the territory using the WHO impregnated paper test and allelic discrimination assay. FINDINGS Eight years surveillance revealed well-installed resistance and the dramatic increase of alleles on the sodium voltage-gated gene, known to confer resistance to pyrethroids (PY). In addition, we observed that populations were resistant to malathion (organophosphorous, OP) and alpha-cypermethrin (PY). Some resistance was also detected to molecules from the carbamate family. Finally, those populations somehow recovered susceptibility against fenitrothion (OP). In addition, other species distributed in urban areas revealed to be also resistant to pyrethroids. CONCLUSION The resistance level can jeopardize the efficiency of chemical adult control in absence of other alternatives and conducts to strongly rely on larval control measures to reduce mosquito burden. Vector control strategies need to evolve to maintain or regain efficacy during epidemics.


Subject(s)
Animals , Pyrethrins/pharmacology , Insecticide Resistance/drug effects , Insecticide Resistance/genetics , Aedes/drug effects , Mosquito Vectors/drug effects , Insecticides/pharmacology , Mosquito Control/methods , Aedes/genetics , Spatio-Temporal Analysis , Mosquito Vectors/virology , French Guiana , Insect Vectors/drug effects , Insect Vectors/genetics
6.
Rev. bras. parasitol. vet ; 28(4): 802-806, Oct.-Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1057988

ABSTRACT

Abstract Population explosions of the stable fly (Stomoxys calcitrans) have become a serious concern for livestock producers near sugarcane mills in some regions of Brazil due to the insect's massive reproduction on sugarcane byproducts and waste. Despite the limited efficiency of insecticides for controlling stable fly outbreaks, producers still rely on chemical control to mitigate the alarming infestations in affected areas. This study evaluated the susceptibility of S. calcitrans populations to cypermethrin in the state of Mato Grosso do Sul, Brazil. Stable flies were tested from three field populations and two colonies, established from flies previously collected at sugarcane mills. Wild flies were collected with Nzi traps in areas of sugarcane plantations. Both wild and colonized flies were exposed to eleven concentrations of cypermethrin in impregnated filter paper bioassays. All the populations proved to be resistant to cypermethrin, with resistance factors among field populations ranging from 6.8 to 38.6. The intensive use of insecticides has led to the development of pyrethroid resistance in stable fly populations in the proximities of sugarcane mills in the state of Mato Grosso do Sul.


Resumo Explosões populacionais da mosca-dos-estábulos (Stomoxys calcitrans) tornaram-se uma séria preocupação para a pecuária próxima a usinas de cana-de-açúcar em algumas regiões do Brasil, devido à massiva reprodução da mosca em resíduos e subprodutos do processamento da cana. Apesar da limitada eficiência dos inseticidas no controle dos surtos desta mosca, produtores dependem do controle químico para mitigar as alarmantes infestações nas áreas afetadas. Este estudo objetivou avaliar a suscetibilidade de populações de S. calcitrans a piretroides no estado de Mato Grosso do Sul, Brasil. Moscas-dos-estábulos de três populações de campo e duas colônias, estabelecidas a partir de moscas previamente coletadas em usinas de cana-de-açúcar, foram testadas. Moscas selvagens foram coletadas com armadilhas Nzi em áreas de cana. Moscas coletadas foram expostas a onze concentrações de cipermetrina em bioensaios com papel de filtro impregnado. Todas as populações testadas mostraram-se resistentes ao piretroide, com fatores de resistência variando de 6,8 a 38,6 nas populações de campo. O uso intensivo de inseticidas tem levado ao desenvolvimento de resistência da mosca-dos-estábulos a piretroides em populações próximas a usinas de cana-de-açúcar no estado do Mato Grosso do Sul.


Subject(s)
Animals , Pyrethrins/pharmacology , Muscidae/drug effects , Insecticides/pharmacology , Biological Assay , Brazil , Insecticide Resistance , Lethal Dose 50
7.
Article in Chinese | WPRIM | ID: wpr-781256

ABSTRACT

OBJECTIVE@#To study the role of Nrf2/ARE signaling pathway in cypermethrin-induced oxidative stress and apoptosis of cerebral cortex neurons in C57BL/6 mice.@*METHODS@#The cortical neurons of C57BL/6 mice were cultured and identified, and a cypermethrin-induced cell injury model was established by treating the cells with 0, 25, 50 and 100 μmol/L of cypermethrin for 48 h. CCK-8 assay was used to analyze the effects of cypermethrin on the cell viability, and the fluorescence probe DCFH-DA was used for detecting intracellular reactive oxygen species (ROS); flow cytometry was performed for determining the apoptosis rate of the cells. The mRNA and protein expression levels of Nrf2 and its downstream genes HO-1 and NQO1 were detected using qPCR and Western blotting.@*RESULTS@#Exposure to cypermethrin at different doses inhibited the viability of the cultured cortical neurons. With the increase of cypermethrin dose, the viability of the neurons decreased progressively, the intracellular ROS and the cell apoptosis rate increased, and the neuronal injury worsened. At the dose of 50 and 100 μmol/L, cypermethrin significantly down-regulated the expressions of HO-1, NQO1 and Nrf2 at both the mRNA and protein levels in the cells ( < 0.01).@*CONCLUSIONS@#Cypermethrin exposure shows a dose-dependent neurotoxicity by inhibiting Nrf2/ARE signaling pathway, down-regulating the expression of Nrf2 and its downstream genes HO-1, NQO1 mRNA and protein, and inducing oxidative damage and apoptosis in primary mouse cortical neurons, .


Subject(s)
Animals , Carboxylic Ester Hydrolases , Cerebral Cortex , Mice , Mice, Inbred C57BL , NF-E2-Related Factor 2 , Neurons , Pyrethrins , Signal Transduction
8.
Rev. cuba. med. trop ; 70(3): 1-9, set.-dic. 2018. tab
Article in Spanish | LILACS, CUMED | ID: biblio-991100

ABSTRACT

Introducción: Aedes aegypti es vector de virus dengue, chikungunya y Zika en Costa Rica. Su alta incidencia y carencia de vacunas hacen del control vectorial, incluyendo el químico, la única alternativa para disminuir su transmisión. El uso reiterativo de insecticidas propicia su resistencia. Objetivo: Determinar la resistencia y mecanismos de detoxificación enzimática a temefós e insecticidas piretroides en cepas de Ae. aegypti de tres distritos de la Región Pacífico Central de Costa Rica. Métodos: La resistencia a temefós, deltametrina y cipermetrina fue determinada en tres cepas de Barranca, Jacó y Quepos mediante bioensayos en larvas. Para cada insecticida se calculó la concentración letal 50 por ciento (CL50) y un factor de resistencia 50 por ciento(FR50), empleando la cepa Rockefeller como control. Ante la ocurrencia de resistencia, se repitieron los bioensayos utilizando butóxido de piperonilo, S,S,S, tributilfosforotritioato y ácido etacrínico que inhiben monooxigenasas, esterasas y glutatión S transferasa, respectivamente. Resultados: Ninguna cepa mostró resistencia a temefós. Las cepas Barranca y Jacó fueron resistentes a deltametrina (FR50= 7,38; 28,23, respectivamente). La cepa Jacó mostró, adicionalmente, resistencia a cipermetrina (FR50= 7,70). La cepa Quepos no mostró resistencia a ningún piretroide. Solo la cepa Barranca mostró disminución de resistencia a deltametrina asociada al butóxido de piperonilo denotando vinculación con monooxigenasas (FR50: 10,10). Para los otros casos de resistencia, ninguno de los sinergistas disminuyó la resistencia. Conclusiones: Las larvas de Ae. aegypti de las localidades evaluadas no mostraron resistencia a temefós. Respecto a piretroides se evidenció la aparición de resistencia que posiblemente no es mediada por detoxificación enzimática(AU)


Introduction: Aedes aegypti is the vector of dengue, chikungunya, and Zika viruses in Costa Rica. The high incidence and the lack of vaccines make vector control, including chemical control, the only measure to prevent transmission. The repetitive use of insecticides may induce resistance. Objective: To determine resistance and enzymatic detoxifying mechanisms to temephos and pyrethroids insecticides in strains of Ae. aegypti from three districts of the Central Pacific Region of Costa Rica. Methods: Resistance to temephos, deltamethrin, and cypermethrin was determined in three strains of Barranca, Jacó, and Quepos by larval bioassays. In each test, the lethal concentration 50 percent (LC50) and a factor of resistance 50 percent (FR50) were calculated, using the Rockefeller strain as control. When resistance was observed, the bioassays were repeated using piperonyl butoxide, S,S,S, tributylphosphorotritioate, and ethacrynic acid, that inhibit monoxygenases, esterases, and glutathione S- transfererase, respectively. Results: None of the strains were resistant to temephos. Resistance to deltamethrin (FR50= 7.38 and FR50= 28.23, respectively) was determined in the strains from Barranca and Jacó, while resistance to cypermethrin was detected only in Jacó (FR50= 7.70). The Quepos strain was not resistant to any pyrethroid. Only the Barranca strain showed a decrease in the resistance to deltamethrin when piperonyl butoxide was used, linking the resistance to monooxygenase enzymes (FR50: 10.10). For the other cases, none of the synergists decreased the resistance. Conclusions: Larvae of Ae. aegypti from the localities evaluated were not resistant to temephos. With respect to pyrethroids, results show an emergence of resistance that may not be mediated by enzymatic detoxification(AU)


Subject(s)
Vector Control , Pyrethrins/standards , Aedes/pathogenicity , Costa Rica , Vector Control
9.
Acta toxicol. argent ; 26(1): 19-31, mayo 2018. ilus, tab
Article in Spanish | LILACS | ID: biblio-973613

ABSTRACT

Los piretroides son insecticidas ampliamente usados no sólo en el ámbito agropecuario y doméstico sino también en salud pública. Una vez absorbidos, son rápidamente metabolizados a compuestos polares eliminados por vía renal. Uno de los metabolitos común a un gran número de piretroides es el ácido 3-fenoxibenzoico (3-PBA) el cual es utilizado como marcador de exposición. Se presenta en este trabajo, la validación de una metodología analítica para la determinación del 3-PBA utilizando QuEChERS acoplado a microextracción líquido-líquido dispersiva con tricloroetileno como disolvente extractivo y cromatografía líquida de alta resolución con detector de foto-arreglo de diodos. La validación se realizó con muestras aisladas de orina de voluntarios adultos de ambos sexos sin exposición conocida y orina sintética. El método resultó lineal en el intervalo 9 μg L-1-79 μg L-1; los límites de detección y cuantificación fueron de 3 μg L-1 y 9 μg L-1, respectivamente. No se observaron señales de interferentes a los tiempos de retención del 3-PBA y del ácido 2-fenoxibenzoico (2-PBA), estándar interno, en las muestras de orina blanco. Las señales cromatográficas en las muestras enriquecidas fueron espectralmente homogéneas. Las precisiones intradiarias (RSDr%) (n= 5) para 9 μg L-1 estuvieron comprendidas entre 9,3%-9,9% y para 27 μg L-1 entre 5,9%-10,6%. Las precisiciones interdiarias (RSDint%) (n=15) para los mismos niveles de concentración fueron de 11,8% y 9,1%, respectivamente. El rango de porcentajes de recuperación para 9 μg L-1 fue de 87%-119% y para 27 μg L-1 de 70%-91%. Se evaluó la estabilidad del analito en la muestra y en el extracto. El analito resultó estable a -20 °C durante 7 días en la muestra y durante 1 día en el extracto. Los valores de incertidumbre relativa e incertidumbre expandida fueron evaluados mediante la ecuación de Horwitz, los resultados obtenidos fueron para el nivel 9 μg L-1 de 33% y 65% y para el nivel 27 μg L-1 de 28% y 55%. La aplicabilidad del método validado fue evaluada con muestras reales de personas sin exposición laboral conocida, quienes declararon haber usado insecticidas piretroides. El método resultó sensible y selectivo.


Pyrethroid insecticides are used not only in the agricultural and domestic environment, but also in public health. Once absorbed, they are rapidly metabolized into polar compounds eliminated by the kidneys. One of the metabolites common to many pyrethroids is 3-phenoxybenzoic acid (3-PBA) which are used to evaluate exposure. We present in this paper the validation of an analytical methodology for the determination of 3-PBA using QuEChERS coupled to dispersive liquid-liquid microextraction with trichloroethylene as an extractive solvent and high-performance liquid chromatography with a photodiode array detector. Validation was carried out with isolated samples of urine from adult volunteers of both sexes without exposure and synthetic urine. The method was linear in the interval 9 μg L-1-79 μg L-1; the limit of detection and quantitation were 3 μg L-1 and 9 μg L-1, respectively. Interfering signals were not observed in the blank urine samples and the chromatographic signals in the enriched samples were spectrally homogeneous. The within-run precision (RSDr%) (n = 5) for 9 μg L-1 were between 9.3%-9.9% and for 27 μg L-1 between 5.9%-10.6%. The between-run precision (RSDint%) (n = 15) for the same concentration levels were 11.8% and 9.1%, respectively. The recovery for 9 μg L-1 ranged from 87%-119% and for 27 μg L-1 from 70%-91 %. The stability of the analyte was evaluated in the sample and in the extract. The analyte in the sample was stable at -20 °C for 7 days and in the extract was stable for 1 day. The values of relative uncertainty and expanded uncertainty obtained by the Horwitz equation were 33% and 65% for 9 μg L-1, and 28% and 55% for 27 μg L-1. The applicability of the validated method was evaluated with real samples of people without known occupational exposure, who declared having used pyrethroid insecticides. The method was sensitive and selective.


Subject(s)
Humans , Pyrethrins/poisoning , Pyrethrins/toxicity , Biomarkers/urine , Biomarkers/analysis , Chromatography, Liquid/methods , Insecticides/poisoning , Insecticides/toxicity
10.
Rev. Inst. Adolfo Lutz ; (77): 1-10, 2018. mapas, graf, tab, ilus
Article in Portuguese | LILACS, SES-SP, SESSP-ACVSES, SESSP-IALPROD, SES-SP, SESSP-IALACERVO | ID: biblio-1119220

ABSTRACT

O objetivo deste artigo é apresentar os principais resultados do Projeto de Inovação Tecnológica em Saúde realizado entre 2014 e 2015, destacando-se o uso de coleiras impregnadas com deltametrina a 4% em cães em uma região endêmica para leishmaniose visceral (LV), o município de Votuporanga, São Paulo, Brasil. Neste município, anterior à realização do projeto, eram registrados muitos casos caninos e humanos da doença, com elevada taxa de letalidade. Durante o projeto, foram monitorados cerca de 16,5 mil cães, examinadas 25.700 amostras de sangue, considerando-se as perdas e as entradas de novos animais durante os quatro inquéritos sorológicos. Após sua finalização, verificou-se uma diminuição da prevalência e incidência de LV canina, assim como do número de casos humanos. A diminuição dos casos caninos foi correlacionada positivamente aos casos humanos no período de 2011 a 2016 (Correlação de Pearson de 0.914, p-valor<0.05). Além disso, a análise espacial dos resultados corrobora a diminuição ou desaparecimento da concentração de casos caninos e, consequentemente, de fontes e de infecção nas áreas endêmicas à medida que avançaram no tempo e espaço as diferentes etapas de desenvolvimento do projeto. Apesar da drástica redução na incidência da LV canina, ainda permaneceram algumas áreas críticas. Os resultados delineados sugerem a revisão de protocolos e manuais demonstrando a efetividade do uso das coleiras como medida preventiva e potencial no controle da LV. (AU)


This paper aims to present the main results of the Health Technology Innovation Project carried out between 2014 and 2015, which evaluates the use of 4% deltamethrin-impregnated collars in dogs, in an endemic region for visceral leishmaniasis (VL), the municipality of Votuporanga, São Paulo, Brazil. Before this project, Votuporanga had notified canine and human cases of the disease, with a high case fatality rate. We monitored approximately 16.5 thousand dogs, 25,700 blood samples analyzed, considering losses and entrances of new animals during the four serological surveys. After the project, the prevalence and incidence of canine VL decreased as well as the number of human cases. We found a positive correlation between the decrease of infected dogs and human cases from 2011 to 2016 (Pearson correlation of 0.914, p-value <0.05). Furthermore, the spatial analysis of the results indicated areas with canine cases concentration that decreased its intensity or disappeared concomitantly to the project levels in the space-time. Despite the drastic reduction in the incidence of canine VL, some critical areas remain. The current results suggest the review of protocols and manuals demonstrating the effectiveness of the use of collars as a preventive measure and potential in the control of VL. (AU)


Subject(s)
Animals , Dogs , Pyrethrins/administration & dosage , Dog Diseases/prevention & control , Evaluation of the Efficacy-Effectiveness of Interventions , Insecticides/administration & dosage , Leishmaniasis, Visceral/prevention & control , Leishmaniasis, Visceral/veterinary , Spatial Analysis
11.
Rev. bras. parasitol. vet ; 26(4): 500-504, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-1042458

ABSTRACT

Abstract This study evaluated the acaricidal efficiency of synthetic pyrethroids (SP) associated with organophosphates (OP) against Rhipicephalus (Boophilus) microplus populations in the state of Rio Grande do Sul, Southern Brazil. Ticks were collected in 54 cattle farms and tested using in vitro adult immersion test against four commercially available acaricide mixtures of SP and OP. Only one of four acaricides, comprising a mixture of cypermethrin, chlorpyrifos, and fenthion, had a mean efficiency higher than 95%, and was effective in 94.44% (51/54) of the cattle farms tested. The acaricide with a mixture of cypermethrin, chlorpyrifos, and citronelall had the lowest mean efficiency (62.11%), and was effective in 29.62% (16/54) of cattle farms tested. Furthermore, R. (B.) microplus in Southern Brazil exhibited differing degrees of resistance to SP and OP mixtures. The results suggest that the presence of fenthion contributes to the higher efficiency of the formulation with this active principle. This is possibly due to its recent commercial availability, as tick populations have been lower challenged with this product. Monitoring the resistance of ticks to carrapaticides is essential to maximize the efficiency of these products in the control of R. (B.) microplus.


Resumo Este estudo avaliou a eficiência acaricida de piretroides sintéticos (SP) associados a organofosforados (OP) sobre populações de Rhipicephalus (Boophilus) microplus no estado do Rio Grande do Sul, Brasil. Carrapatos foram coletados em 54 fazendas de bovinos, testados in vitro pelo teste de imersão de teleóginas, contra quatro associações acaricidas comercialmente disponíveis de SP e OP. Apenas um dos quatro acaricidas, constituído por associação de cipermetrina, clorpirifós e fenthion, teve eficiência média superior a 95%, sendo eficaz em 94,44% (51/54) das fazendas testadas. O acaricida com associação de cipermetrina, clorpirifós e citronelal teve menor eficiência média (62,11%), sendo efetivo em 29,62% (16/54) das fazendas testadas. Além disso, o R. (B.) microplus no sul do Brasil, apresentou diferentes graus de resistência às associações de SP e OP. Os resultados sugerem que a presença do fenthion contribui para a maior eficiência da formulação com esse princípio ativo. Possivelmente, isso ocorre em função da sua recente introdução no mercado, já que as populações de carrapatos foram pouco desafiadas com este produto. Monitorar a resistência dos carrapatos aos carrapaticidas é fundamental para maximizar a eficiência desses produtos no controle de R. (B.) microplus.


Subject(s)
Organophosphates/administration & dosage , Pyrethrins/administration & dosage , Rhipicephalus/drug effects , Acaricides/administration & dosage , Insecticides/administration & dosage , Pyrethrins/chemical synthesis , Brazil , Insecticides/chemical synthesis
12.
Pesqui. vet. bras ; 37(2): 97-104, fev. 2017. tab
Article in English | ID: biblio-833981

ABSTRACT

A survey of veterinary drug residues in bulk milk tank from Minas Gerais State, Brazil, was carried out through a broad scope analysis. Here, 132 raw milk samples were collected at 45 dairy farms in Minas Gerais from August 2009 to February 2010, and analyzed for 42 analytes, comprising pyrethroids, macrocyclic lactones and antibacterials, using liquid chromatography coupled with mass spectrometry in tandem mode and gas chromatography with electron capture detection. Within all milk samples, at least one veterinary drug residue was identified in 40 milk samples (30.30%) by confirmatory tests, whereas 16 samples (12.12%) showed the presence of at least two residues. With regard to the Brazilian maximum residue levels, 11 milk samples (8.33%) were non-compliant according to Brazilian Legislation. The veterinary drugs detected in the non-compliant milk samples include penicillin V (one sample), abamectin (one sample) and cypermethrin (nine samples). Furthermore, the antibacterial screening methods failed to identify most of the positive samples that were detected by confirmatory tests, leading to a large discrepancy between the screening and confirmatory antimicrobial tests. Thus, the present study indicated that the veterinary drugs residues still represents a great concern for the milk production chain.(AU)


Avaliou-se a presença de 42 analitos, incluindo piretróides, lactonas macrocíclicas e antimicrobianos em 132 amostras de leite de tanque proveniente de 45 propriedades leiteiras localizadas no Estado de Minas Gerais. Para tal, utilizou-se a cromatografia líquida acoplada a espectrofotometria de massas tandem e cromatografia gasosa com detector com captura de elétrons. Dentre todas as amostras de leite, 40 (30,30%) amostras de leite de tanque apresentaram a presença de pelo menos um analito, enquanto 16 amostras (12,12%) de leite demonstraram a presença de pelo menos dois analitos. Considerando os limites estabelecidos pela legislação brasileira, 11 amostras de leite (8,33%) seriam consideradas como não conforme. Ademais, os testes de triagem para detecção de antimicrobianos no leite não conseguiram identificar a maioria das amostras positivas nos testes confirmatórios, levando a grande discrepância entre estes testes. Desta forma, os resultados do presente estudo indicam que os períodos de descarte do leite, especialmente para piretróides, não foram plenamente respeitados por todos os produtores de leite. Além disto, uma discrepância entre os resultados dos testes confirmatórios e os testes de triagem foi observada.(AU)


Subject(s)
Anti-Infective Agents/analysis , Drug Residues/analysis , Lactones/analysis , Milk/chemistry , Pyrethrins/analysis , Anthelmintics , Cattle , Pesticides , Veterinary Drugs/analysis
13.
Mem. Inst. Oswaldo Cruz ; 112(2): 108-115, Feb. 2017. tab
Article in English | LILACS | ID: biblio-841761

ABSTRACT

BACKGROUND New brands of potential long lasting insecticide nets (LLINs) and LLIN treatment kits require field evaluation before they are used in a vector control programme. OBJECTIVES The aim of this study was to evaluate the bio-efficacy, usage, washing practice and physical integrity of nets treated with LLIN treatment kit, ICON MAXX in a phase III field trial in Odisha state, India. METHODS A total of 300 polyester nets treated with ICON MAXX and 140 polyester nets treated conventionally with lambda-cyhalothrin CS 2.5% ITNs were distributed. The bio-efficacy was evaluated with WHO cone bioassay. The chemical analysis of netting pieces was done at the beginning, after 12 and 36 months of the trial. FINDINGS After one year of distribution of nets, the bioassay showed 100% mortality on both ITNs and ICON MAXX treated nets. At 36 months, the overall pass rate was 58.8% and the mean lambda-cyhalothrin content of LLINs was 34.5 mg ai/m2, showing a loss of 44.4% of the original concentration. CONCLUSION ICON MAXX treated LLIN was found to retain bio-efficacy causing 97% knockdown of Anopheles stephensi up to 30 months and met the WHOPES criteria. However, the desired bio-efficacy was not sustained up to 36 months.


Subject(s)
Humans , Animals , Pyrethrins/pharmacology , Mosquito Control/instrumentation , Insecticide-Treated Bednets/statistics & numerical data , Mosquito Vectors/drug effects , Anopheles/drug effects , Time Factors , Biological Assay , India , Laundering/methods , Malaria/prevention & control
14.
Rev. Inst. Med. Trop. Säo Paulo ; 59: e18, 2017. tab, graf
Article in English | LILACS | ID: biblio-842766

ABSTRACT

ABSTRACT The aim of the present study was to examine the resistance of PermaNet® 2.0 bed nets against repeated washing and environmental factors by using bioassay tests. After 5, 15 and 21 washings with detergents and by using bioassay tests, the resistance of 40 PermaNet® 2.0 bed nets was compared with that of 40 bed nets conventionally treated with one K-O tablet. To examine the long-term resistance, 31 PermaNet® 2.0 bed nets were also distributed among villagers, and were re-collected to perform bioassay tests after 1, 2 and 5 years. In the first phase of this study, the insecticidal effect of the conventionally-treated nets significantly decreased due to repeated washings (P < 0.001); however, it was not significant regarding PermaNet® 2.0 bed nets (P = 0.92 in continuous exposure and P = 0.12 in mortality tests). In the long-term phase of this study, the time required for knockdown of PermaNet® 2.0 increased over the first 2 years and then decreased. In addition, the mortality rate decreased over the first 2 years and then increased. In conclusion, it seems that the technique used by the manufacturer for impregnation of PermaNet® 2.0 bed nets has an acceptable efficiency in comparison with conventional techniques.


Subject(s)
Animals , Insecticide-Treated Bednets , Insecticides , Malaria/prevention & control , Mosquito Control/methods , Nitriles , Pyrethrins , Biological Assay , Evaluation Studies as Topic , Laundering , Time Factors
15.
Arq. bras. med. vet. zootec ; 68(6): 1721-1726, nov.-dez. 2016. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-827955

ABSTRACT

The present study attempted to identify climate conditions that are associated with the occurrence of pyrethroid residues using a multivariate principal component analysis (PCA). A total of 132 raw milk samples were collected from dairy farms in Minas Gerais State - Brazil and analyzed for seven analytes using gas chromatography with electron capture detection. Of the 132 milk samples, pyrethroid residues were identified in 14 (10.6%) milk samples, of which 12 (9.1%) and two (1.5%) milk samples had the identification of cypermethrin and deltamethrin, respectively. From those samples, nine (6.8%) milk samples were regarded as non-compliant for cypermethrin with this analyte concentration above the maximum residue limits set by Brazilian legislation. A PCA assessing pyrethroid residues in bulk tank milk demonstrated that the average temperature and the Temperature-Humidity Index were associated with pyrethroids residues in bulk milk tank, although the relative humidity was inversely correlated. Thus, the data analysis indicated that the pyrethrid residues associated with some climate conditions can predict the moments with higher risk of occurrence of pyrethroid residues in bulk tank milk.(AU)


O presente trabalho objetivou identificar fatores climáticos associados à ocorrência de resíduos de piretroides em amostras de leite de tanque por análise multivariada de componentes principais (ACP). Para o presente trabalho, 132 amostras de leite cru foram coletadas em fazendas leiteiras localizadas no estado de Minas Gerais (Brasil) e analisadas por sete analitos por cromatografia gasosa com detector por captura de eletróns para detecção de resíduos de piretroides. Das 132 amostras de leite analisadas, a presença de resíduos de piretroides foi detectada em 14 amostras (10,6%), e em 12 (9,1%) e duas (1,5%) foram detectados cipermetrina e deltametrina, respectivamente. Destas amostras, em nove (6,8%) a concentração de cipermetrina encontrada foi maior que a permitida pela legislação brasileira. A ACP demonstrou que a presença de resíduos de piretroides no leite de tanque ocorreu menos frequentemente nos dias com maior umidade relativa, embora a presença desses resíduos estivesse associada a maior temperatura média e a maior índice de temperatura e umidade. Dessa forma, conclui-se que alguns índices climáticos podem predizer períodos com maior risco de ocorrência de resíduos de piretroides no leite de tanque.(AU)


Subject(s)
Drug Residues/analysis , Hot Temperature , Humidity , Milk/toxicity , Pesticides/analysis , Pyrethrins/analysis , Cattle
16.
Article in English | WPRIM | ID: wpr-59540

ABSTRACT

BACKGROUND: According to US-EPA report, the use of pyrethrins and pyrethroids has increased during the past decade, and their area of use included not only in agricultural settings, but in commerce, and individual household. It is known that urinary 3-PBA, major metabolite of pyrethroid, have some associations with health effect in nervous and endocrine system, however, there’s no known evidence that urinary 3-PBA have associations with obesity. METHOD: We used data of 3671 participants aged above 19 from the Korean National Environmental Health Survey in 2009–2011. In our analysis, multivariate piece-wise regression and logistic regression analysis were used to investigate the association between urinary 3-PBA (3-Phenoxybenzoic Acid) and BMI. RESULT: Log-transformed level of urinary 3-PBA had significantly positive association with BMI at the low-level range of exposure (p < 0.0001), and opposite associations were observed at the high level exposure (p = 0.04) after adjusting covariates. In piece-wise regression analysis, the flexion point that changes direction of the associations was at around 4 ug/g creatinine of urinary 3-PBA. As quintiles based on concentration of urinary 3-PBA increased to Q4, the ORs for prevalence of overweight (BMI ≥ 23 kg/m2) were increased, and the OR of Q5 was lower than that of Q4 (OR = 1.810 for Q4; OR = 1.483 for Q5). In the analysis using obesity (BMI ≥ 25 kg/m2) as outcome variable, significant associations were observed between obesity and quintiles of 3-PBA, however, there were no differences between the OR of Q5 and that of Q4 (OR = 1.659 for Q4; OR = 1.666 for Q5). CONCLUSION: Our analysis suggested that low-level of pyrethroid exposure has positive association with BMI, however, there is an inverse relationship above the urinary 3-PBA level at 4 ug/g creatinine. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s40557-015-0079-7) contains supplementary material, which is available to authorized users.


Subject(s)
Adult , Body Mass Index , Commerce , Creatinine , Endocrine System , Environmental Health , Family Characteristics , Humans , Logistic Models , Methods , Multivariate Analysis , Obesity , Overweight , Prevalence , Pyrethrins
17.
Article in English | WPRIM | ID: wpr-44148

ABSTRACT

Chlorfenapyr is a widely used, moderately hazardous pesticide. Previous reports have indicated that chlorfenapyr intoxication can be fatal in humans. We reported the first non-fatal case of chlorfenapyr-induced toxic leukoencephalopathy in a 44-year-old female with resolution of extensive and abnormal signal intensities in white matter tracts throughout the brain, brain stem, and spinal cord on serial magnetic resonance imaging.


Subject(s)
Adult , Brain/diagnostic imaging , Brain Stem/diagnostic imaging , Female , Humans , Insecticides/toxicity , Leukoencephalopathies/etiology , Magnetic Resonance Imaging , Pyrethrins/toxicity , Spinal Cord/diagnostic imaging , White Matter/diagnostic imaging
18.
Belo Horizonte; s.n; 2016. 77 p.
Thesis in Portuguese | LILACS, ColecionaSUS | ID: biblio-943156

ABSTRACT

A persistência do Triatoma infestans e a transmissão contínua de Trypanosoma cruzinos Vales Inter-Andinos e no Grande Chaco da Bolívia são de grande importância. Na última década, focos silvestres desta espécie foram descritos em amplas áreas, na qual o alcance das estratégias de controle do vetor é limitado, sendo frequentes os relatos de resistência do T. infestans a inseticidas, que incluem populações silvestres e domésticas. O presente estudo teve como objetivo caracterizar o perfil de suscetibilidade (1) e hereditariedade (2) de populações silvestres e domésticas de T. infestans da Bolívia à deltametrina, bem como descrever a área de distribuição das populações resistentes a diferentes piretróides na América do Sul (3). 1) Foram avaliadas nove populações de T. infestans silvestres e domésticas do Grande Chaco e dos Vales Inter-Andinos da Bolívia. Três amostras silvestres de T. infestans(dark morph) do Chaco (Santa Cruz) foram suscetíveis a deltametrina (RR50 de <2), com 100% de mortalidade em resposta a dose diagnóstica (DD). A população doméstica de Villa Montes do Grande Chaco (Tarija) apresentou altos níveis de resistência (RR50 = 129,12 e 0% DD).


Do mesmo modo, as populações domésticas dos Vales Inter-Andinos (Cochabamba) apresentaram RR50 > 9, sendo as populações silvestres menos suscetíveis, com RR50 >5 do que SRL. 2) Cruzamentos experimentais foram realizados entre uma colônia suscetível RR50=0,62 (S), uma resistente RR50=129,12 (R) e com susceptibilidade reduzida RR50=5,04 (SR), em ambas as direções (♀x♂ e ♂x♀). O modo de herança do caráter resistente foi determinado pelo grau de dominância (DO) e dominância efetiva (DML). A hereditariedade (h2) foi estimada a partir da colônia R selecionada durante duas gerações, utilizando a dose diagnóstica (10 ng.i.a./ninfa).


O resultado para DO e DML (<1) indica que a resistência é um caráter de dominância incompleta e de herança autossômica. A Dose Letal 50% (DL50) para F1 de ♀Sx♂R e ♂Sx♀R foi de 0,74 e 3,97 respectivamente, revelando efeito de diluição da resistência inicialmente observada. Por outro lado, foi observado um incremento da RR50 de 2,25 vezes (F1) e 26,83 vezes (F2) na população selecionada em comparação com a colônia parental. 3) Foi compilado um total de 24 artigos que avaliaram a suscetibilidade a diferentes piretróides em 222 populações de T. infestans coletadas no campo dos países de Argentina, Bolívia, Brasil e Paraguai. A relação entre resistência aos inseticidas (avaliada por critérios diferentes) e diferentes variáveis ambientais foi estudada utilizando modelo linear generalizado. A DL50 mostrou uma forte relação linear com a RR50. Análise estatística descritiva demonstrou que a distribuição de frequência da Log (DL50) é bimodal, sugerindo a existência de dois grupos estatísticos (um grupo de menor e outro com maior Log (DL50). Finalmente, o modelo significativo incluindo 5 variáveis ambientais referentes a temperatura e precipitação, revelou concentração das populações com altas DL50 sobre a região identificada como o centro de dispersão de T. infestans. Os dados obtidos neste estudo contribuem com informações sobre a variabilidade do perfil de resistência, ocorrência e distribuição de populações resistentes na Bolívia


Subject(s)
Animals , Chagas Disease/prevention & control , Pyrethrins/therapeutic use , Triatoma/pathogenicity , Triatominae/pathogenicity , Trypanosoma cruzi/parasitology
19.
Journal of the Egyptian Society of Parasitology. 2016; 46 (1): 131-134
in English | IMEMR | ID: emr-180168

ABSTRACT

The extensive use of insecticides in public health and agriculture sectors is the main reason for development of resistance in fleas associated in domestic rodents. The present work was planned to investigate the insecticidal efficacy of Lambda-cyhalothrin, Chlorpyrifos and Fenitrothion against rat flea [Xenopsylla cheopis] infesting rodent species in Giza Governorate, Egypt. The lethal concentration LC[50] and Lc[90] of population percent were obtained from the established regression log concentrate-response lines. Data indicated that the values of lethal concentration [LC[50]] were 0.293, 1.725 and 2.328% for Lambda-cyhalothrin, chlorpyrifos and Fenitrothion, respectively. The values of lethal concentration [Lc[90]] were 0.467, 2.839 and 5.197% for Lambda-cyhalothrin, chlorpyrifos and Fenitrothion, respectively


Subject(s)
Animals , Flea Infestations , Insecticides , Rodent Diseases , Rats , Fenitrothion , Chlorpyrifos , Nitriles , Pyrethrins
20.
Rev. MVZ Córdoba ; 20(supl.1): 4874-4883, Dec. 2015. ilus, tab
Article in English | LILACS, COLNAL | ID: lil-769246

ABSTRACT

Objective. Due to the importance of controlling ectoparasites, associated with the necessity of technical knowledge on the safety of topical treatment with organophosphates, pyrethroids and piperonyl butoxide to the animal organism, this bioassay was carried out to evaluate the clinical safety of the association of dichlorvos (45%) + cypermethrin (5%) + piperonyl butoxide (25%) administered by spray on the skin of cattle, through the study of clinical parameters, biochemical, haematological and behavioral changes. Materials and methods. Sixteen crossbred animals with a mean age of 18 months, males and females grouped into two treatments with eight animals each: T1 (1:800 v/v) and T2 (1:200 v/v). Were collected blood samples at six different times: before treatment (BT), 24, 48, 72, 96 and 192 hours post treatment (HPT). Results. The antiparasitic association administered by spray on the skin did not result in changes in the enzymatic activity of ALT, AST, GGT and ALP, as well as in serum albumin, triglycerides, cholesterol, urea and creatinine, demonstrating the safety of this antiparasitic compound for maintaining hepatic and renal functionality. The erythrocyte, leukocyte and platelet studies showed no changes caused by treatments, and no clinical signs and behavioral changes were observed after treatment. Conclusions. These findings demonstrated good safety margin for spray treatment on the skin with this antiparasitic compound, even when administered at a dilution of 1:200 v/v, which is four times the dose recommended for ectoparasite control.


Objetivo. Debido a la importancia del control de ectoparásitos en bovinos, asociado a la necesidad de conocimientos técnicos sobre la seguridad del tratamiento tópico con organofosforados, piretroides y butóxido de piperonilo, se realizó este bioensayo para la evaluación de la seguridad clínica de la asociación de diclorvos (45%) + cipermetrina (5%) + butóxido de piperonilo (25%), administrado por aspersión en la piel del ganado bovino, a través del estudio de los parámetros clínicos, bioquímicos, hematológicos y comportamentales. Materiales y métodos. Dieciséis animales entre machos y hembras cruzados con edad media de 18 meses, agrupados en dos tratamientos de ocho animales cada uno: T1 (1:800 v/v) y T2 (1:200 v/v). Fueron colectadas muestras de sangre en seis momentos diferentes: antes del tratamiento (BT), 24, 48, 72, 96 y 192 horas post tratamiento (HPT). Resultados. La asociación antiparasitaria administrada por aspersión en la piel no alteró la actividad enzimática de ALT, AST, GGT y FA, así como la albúmina, triglicéridos, colesterol, urea y creatinina, que demuestra la seguridad de este compuesto antiparasitario en la función renal y hepática. El análisis de eritrocitos, leucocitos y plaquetas no mostraron cambios en los tratamientos, tampoco fueron observados signos clínicos y de comportamiento post tratamiento. Conclusiones. Estos resultados demostraron buen margen de seguridad en el tratamiento por aspersión en la piel con este compuesto antiparasitario, incluso cuando se administra en una dilución de 1:200 v/v, que es cuatro veces la dosis recomendada para el control de ectoparásitos.


Subject(s)
Cattle , Organophosphates , Piperonyl Butoxide , Pyrethrins , Sprinkle Irrigation
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