ABSTRACT
Resumen: Objetivo: Evaluar el efecto de repelencia espacial contra Ae. aegypti de dos compuestos químicos impregnados en diferentes tipos de telas. Material y métodos: El estudio se realizó en el periodo 2015-2016 en el Centro Regional de Investigación en Salud Pública, del Instituto Nacional de Salud Pública. Se utilizó el Sistema de Procesamiento de Alto-rendimiento para evaluar la respuesta de Ae. aegypti a transflutrina y linalol, impregnados individualmente a diferentes concentraciones en popelina, algodón y poliéster. También se determinó el efecto de sus mezclas, lavado sobre la residualidad y porcentaje de protección. Resultados: La mayor respuesta de repelencia espacial fue para el tratamiento linalol-algodón al 0.1% (RE= 70 ± 5.77%). La mezcla de linalol 0.1% y transflutrina 0.001% presentó un porcentaje de repelencia espacial similar para los tres tipos de tela. El tratamiento transflutrina-popelina 0.001% mantuvo una residualidad de cinco días. El linalol al 0.1% produjo 62.50% de protección en presencia de un estímulo de atracción. Conclusión: Se sugiere la impregnación de linalol al 0.1% en ropa como medida de protección de las picaduras de Ae. aegypti.
Abstract: Objective: Evaluate the effect of spatial repellency against Ae. aegypti of two chemical compounds impregnated in different types of fabrics. Materials and methods: The study was carried out in the year 2015-2016 in the Centro Regional de Investigación en Salud Pública, del Instituto Nacional de Salud Pública. The high-throughput screening system was used to evaluate the response of Ae. aegypti to transfluthrin and linalool, impregnated individually at different concentrations in poplin, cotton and polyester. The effect of their mixtures was also determined, washing on residuality and percentage of protection. Results: The highest spatial repellency response was for 0.1% linalool-cotton treatment (RE = 70 ± 5.77%). The mixture of 0.1% linalool and 0.001% transfluthrin presented a similar spatial repellence percentage for the three types of fabric. The transfluthrin-poplin treatment 0.001% maintained a residual of five days. 0.1% linalool produced a 62.50% protection in the presence of an attraction stimulus. Conclusion: It is suggested the impregnation of 0.1% linalool in clothing as a protection measure for Ae. aegypti.
Subject(s)
Animals , Textiles , Aedes , Cyclopropanes , Fluorobenzenes , Acyclic Monoterpenes , Insect Repellents , Insecticides , Clothing , Mosquito VectorsABSTRACT
Resumen: Objetivo: Evaluar la efectividad de la mezcla de flupyradifurona 26.3 g/L y transflutrina 52.5 g/L aplicada como niebla térmica a mosquitos Aedes vectores de virus dengue, Zika y chikungunya. Material y métodos: Se colocaron grupos de 15 mosquitos de Ae. aegypti (susceptibles y resistentes a piretroides) dentro de jaulas, en sala, recámara y cocina. Posteriormente, se aplicó la mezcla de flupyradifurona y transflutrina dentro de las viviendas a una dosis de 2 y 4 mg/m3, respectivamente. Resultados: La mezcla de flupyradifurona y transflutrina causó mortalidades de 97 a 100% sobre las cepas de mosquitos Aedes y su efectividad fue la misma en los diferentes compartimentos de las viviendas. Conclusiones: La mezcla de flupyradifurona y transflutrina, aplicada en niebla térmica, es una herramienta prometedora para el control de poblaciones de mosquitos Aedes independientemente de su estado de resistencia a insecticidas.
Abstract: Objective: To evaluate the efficacy of thermal fogging of a mixture of flupyrafirudone (26.3 g/L) and transfluthrin (52.5 g/L) against dengue, Zika y chikungunya Aedes mosquito vectors. Materials and methods: Groups of 15 caged Ae. aegypti (susceptible and pyrethroid resistant) mosquitoes were placed in living room, kitchen and bedroom inside houses, after which a dose of 2 and 4 mg/m3 of flupyradifurone and transfluthrine, respectively, was applied as thermal fog. After one hour of exposure mosquitoes were transferred to the laboratory and mortality was recorded after 24 h. Results: The mixture killed 97 to 100% of mosquitoes from the strains and the efficacy was similar independently of their place within the premises. Conclusions: The mixture of flupyrafirudone and transfluthrin applied as thermal fog is a promising tool to control Aedes mosquito populations independently of the pyrethroid-insecticide resistance status.
Subject(s)
Animals , Pyridines , 4-Butyrolactone/analogs & derivatives , Insecticide Resistance , Aedes , Cyclopropanes , Fluorobenzenes , Insecticides , Chikungunya virus , Mosquito Control/methods , Aedes/virology , Aerosols , Dengue Virus , Drug Combinations , Zika Virus , Mosquito Vectors , Housing , MexicoSubject(s)
Humans , Animals , Male , Female , Child , Adolescent , Lice Infestations/epidemiology , Pediculus , Scalp Dermatoses/epidemiology , Indians, North American , Lice Infestations/parasitology , Lice Infestations/transmission , Scalp Dermatoses/parasitology , Socioeconomic Factors , Sex Factors , Prevalence , Cross-Sectional Studies , Risk Factors , Age Factors , Mexico/epidemiologyABSTRACT
Context and Objective: Chagas disease is considered a worldwide emerging disease; it is endemic in Mexico and the state of Coahuila and is considered of little relevance. The objective of this study was to determine the seroprevalence of T. cruzi infection in blood donors and Chagas cardiomyopathy in patients from the coal mining region of Coahuila, Mexico. Design and Setting: Epidemiological, exploratory and prospective study in a general hospital during the period January to June 2011. Methods: We performed laboratory tests ELISA and indirect hemagglutination in three groups of individuals: 1) asymptomatic voluntary blood donors, 2) patients hospitalized in the cardiology department and 3) patients with dilated cardiomyopathy. Results: There were three levels of seroprevalence: 0.31% in asymptomatic individuals, 1.25% in cardiac patients and in patients with dilated cardiomyopathy in 21.14%. Conclusions: In spite of having detected autochthonous cases of Chagas disease, its importance to local public health remains to be established as well as the details of the dynamics of transmission so that the study is still in progress.
Contexto e Objetivo: A doença de Chagas é mundialmente considerada uma doença emergente, é endêmica no México e no estado de Coahuila e considerada de pouca relevância. O objetivo do estudo foi determinar a soroprevalência da infecção pelo T. cruzi em doadores de sangue e cardiomiopatia chagásica em pacientes da região carbonífera de Coahuila, México. Desenho e Local: Estudo epidemiológico, exploratório e prospectivo em um hospital geral no período de janeiro a junho de 2011. Métodos: Foram realizados testes de laboratório ELISA e hemoglutinação indireta em três grupos de indivíduos: 1) doadores de sangue voluntários assintomáticos, 2) pacientes internados na área de cardiologia e 3) pacientes com cardiomiopatia dilatada. Resultados: Foram achados três níveis de soroprevalência: 0,31% em indivíduos doadores de sangue assintomáticos, 1,25% em pacientes cardiopatas e, em pacientes com cardiomiopatia dilatada 21,14%. Conclusão: Detectamos casos autóctones de doença de Chagas em área considerada não endêmica. Deve ser determinada sua importância na saúde pública regional e local, para estabelecer os detalhes do mecanismo de transmissão. O estudo ainda está em desenvolvimento.
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Antibodies, Protozoan/blood , Blood Donors/statistics & numerical data , Chagas Disease/epidemiology , Trypanosoma cruzi/immunology , Coal Mining , Chagas Cardiomyopathy/diagnosis , Chagas Cardiomyopathy/epidemiology , Chagas Disease/diagnosis , Enzyme-Linked Immunosorbent Assay , Hemagglutination Tests , Mexico/epidemiology , Prospective Studies , Seroepidemiologic StudiesABSTRACT
Objetivos. Evaluar la respuesta conductual de la generación F1 de Aedes aegyti (L) colectados en el área metropolitana de Monterrey (Nuevo León, México) frente a tres adulticidas piretroides de uso frecuente en salud pública. Materiales y métodos. Se utilizó un sistema modular novedoso denominado HITSS (High-Throughput Screening System), para evaluar dos respuestas de comportamiento (irritación de contacto y repelencia espacial), así como la toxicidad de tres insecticidas DDT, permetrina y bifentrina a diferentes concentraciones (0,025, 0,25, 25 y 250 nmol/cm2). Resultados. En la concentración 2,5 nmol/cm2, el DDT (4,3 +/- 2,4) y la permetrina (8,0 +/- 1,4) son los insecticidas que tienen mayor efecto irritante (p < 0,05); la bifentrina requiere dosis 20 veces más alta para lograr efectos similares. En repelencia espacial, los tres insecticidas evaluados producen respuestas similares en todas las concentraciones; para DDT de 7 a 14%; permetrina de 9 a 15% y bifentrina de 19 a 27%. La permetrina y bifentrina a concentraciones 0,025 nmol/cm2, producen efectos knockdown superiores a 34%, con una mortalidad 19%, el DDT requiere concentraciones diez veces más altapara lograr efectos similares. Conclusiones. El sistema HITTS puede ser usado para evaluar la respuesta conductual frente a insecticidas.
Objectives. To assess the behavioural response of the F1 generation of Aedes aegyti (L) collected in the Metropolitanarea of Monterrey (Nuevo Leon, Mexico) vs. three adulticides pyrethroids frequently used in public health. Materials and methods. We used a novel modular system called HITSS (High-Throughput Screening System) to evaluate two behavioral responses (contact irritation and spatial repellency), as well as the toxicity of three insecticides DDT, permeathrin and bifenthrin at different concentrations (0.025, 0.25, 25 and 250 nmol/cm2). Results. In the concentration 2.5 nmol/cm2, DDT (4.3 +/- 2.4) and permethrin (8.0 +/- 1.4) were the insecticides that are more irritating effect (p < 0.05); the bifenthrin requires 20 times higher doses to achieve similar effects. In spatial repellency, the three insecticides tested have had a similar responses at all concentrations; DDT: 7 to 14%, permethrin: 9 to 15% and bifenthrin: 19% to 27%. Permethrin and bifenthrin in 0.025 nmol/cm2 concentrations, effects knockdown above 34% with a mortality rate 19%, DDT requires 10 times higher concentrations to achieve similar effects. Conclusions. HITTS system can be used to assess the behavioural response to insecticides.
Subject(s)
Humans , Densovirinae , Insecticides , Insect Repellents , ToxicityABSTRACT
OBJETIVO: Detectar la presencia del virus del oeste del Nilo (VON) en aves, equinos y seres humanos en el noreste de México. MATERIAL Y MÉTODOS: Se buscó en diferentes localidades del noreste de México la presencia de anticuerpos antivirus del oeste del Nilo (anti-VON) en suero de 33 aves, 24 caballos y 237 personas mediante pruebas de ELISA durante el periodo de julio de 2003 a julio de 2006. En los sueros humanos se buscó también el RNA-VON mediante RT-PCR. RESULTADOS: Se encontraron tres aves seropositivas y 15 equinos. En el hombre, 40 por ciento de los sueros fue positivo para anticuerpos IgG y ninguno para anticuerpos IgM. CONCLUSIONES: El VON se encuentra activo en México y se suma a otras enfermedades emergentes transmitidas por vectores que representan un reto a la investigación y a los programas de prevención.
OBJECTIVE: To investigate the presence of WNV in birds, horses and humans in northeast Mexico. MATERIAL AND METHODS: Serum samples from 33 birds, 24 horses and 237 humans were screened by ELISA for Anti-WNV antibodies. Human serum samples were also screened for WNV RNA using an RT-PCR assay. RESULTS: Positive sera were found in three birds and 15 horses. Forty percent of the human serum samples were positive for IgG antibodies and 0 percent for IgM antibodies and viral RNA. CONCLUSIONS: The results of this study show that WNV is present in northeast Mexico and it is a new emergent infectious agent that represents a challenge for research and prevention programs in Mexico.
Subject(s)
Animals , Humans , Birds/blood , Horses/blood , West Nile virus/isolation & purification , MexicoABSTRACT
With the purpose of evaluating the risk of transmission of the Chagas disease in the State of Colima, México, an entomological survey was performed to obtain triatominae and the rate of infection by Trypanosoma cruzi determined by examination of its dejections. Two hundred eighteen houses located in 16 villages were sampled. In each house the intradomestic and peridomestic habitats were examined by the man-hour-house method, sensor boxes and mouse-baited traps. Also, 12 silvatic places were explored around the same areas using the same techniques as the ones sampled. In total, 456 specimens were captured, of which 139 correspond to Triatoma phyllosoma pallidipennis; 80 to T. p. longipennis; one specimen of T. dimidiata and 236 nymphs of Triatoma sp. Two hundred ninety seven insects were captured in the intradomestic habitat, 132 in the peridomestic and 26 in the silvatic. The index of positive houses was 27 percent, located in the central area of the state. The rate of natural infection with T. cruzi showed 25.6 percent. This results confirmed the presence of two important vectors of the Chagas disease in Colima. Its preference for the domestic habitat and its high levels of natural infection with T. cruzi suggested the existence of a significant risk for its transmission in this area of the country
Subject(s)
Humans , Animals , Chagas Disease , Insect Vectors , Triatoma , Trypanosoma cruzi , Housing , Mexico , Risk Factors , TriatominaeABSTRACT
Flebotomo atraidos por cebo humano fueron conectados en un foco de leishmaniais cutanea localizada en el estado de Campeche, Mexico. Colectas fueron llevadas a cabo mensalmente de Febrero 1994 a Enero de 1995 entre las 18:00 a 22:00 h. Lutzomyia cruciata fue la unica especie capturada. El mayor pico plobacional fue encontrado en Marzo con picos similares en Febrero, Diciembre 1994 y Enero 1995. La tasa maxima de picadura de Lu. cruciata estuvo compreendida entre 18:00 e 19:00 h Las hembras hambientes de Lu. cruciata, fueron directamente relacionadas con niveles de humedad relativa entre 88 a 100 por cento. Bajas y altas temperaturas tuvieron un efecto negativo sobre la actividad de Lu. cruciata. Se discute el posible papel de Lu. criciata como vector de leishmaniasis en el estado de Campeche, Mexico
Subject(s)
Humans , Animals , Insect Bites and Stings , Leishmaniasis, Cutaneous/epidemiology , Population Dynamics , Climate Change , Insect Vectors , Mexico , Psychodidae/parasitology , Time FactorsABSTRACT
Se discute el papel del Aedes aegypti (Lineo) en la epidemiología del dengue en México usando como referencia el modelo de la capacidad vectorial. Se presentan comentarios sobre las ventajas y desventajas de cada uno de los componentes de este modelo al momento de su determinación en campo. Se enfatiza cómo la suma de errores metodológicos y de muestreo, afecta finalmente el resultado de la capacidad vectorial. Se subraya la necesidad de incrementar el conocimiento en la biología del Aedes aegypti, como una respuesta a las necesidades de la epidemiología en su tarea de predecir y explicar brotes de dengue, y se comenta sobre variables potenciales de importancia epidemiológica de origen entomológico que del modelo cuantitativo no considera. Finalmente, se menciona la introducción del Aedes albopictus (Skuse) en México y cómo esto viene a complicar más la comprensión de la transmisión del dengue
The role of Aedes aegypti (Lineo) in the epidemiology of dengue fever in Mexico is herein discussed based on the vectorial capacity model. Comments on the advantages and disadvantages of each model component at the time of field determinations are also presented. Emphasis is made on the impact of sampling and method bias on the results of vectorial capacity studies. The paper also addresses the need to increase vector biology knowledge as an input for epidemiological work to explain and predict dengue fever outbreaks. Comments on potential entomological variables not considered by the quantitative model are included. Finally, we elaborate on the introduction of Aedes albopictus (Skuse) in Mexico as a new risk factor and on its implications for the understanding of dengue fever transmission in Mexico.