Infection of Aedes mosquitoes by native Wolbachia in urban cemeteries of Southern Mexico / Infección de mosquitos Aedes con Wolbachia nativa en cementerios urbanos del sur de México

Abstract: Objective: To evaluate the prevalence of Wolbachia infections in Aedes spp. field populations from cemeteries of Southern Mexico. Materials and methods: Six cemeteries were selected to be sampled in the central part of the Soconusco region, Chiapas. Aedes albopictus and Ae. aegypti mosquitoes were collected during the rainy season of 2015. Females were analyzed individually by PCR to determine the presence of Wolbachia. Results: A field overall prevalence of 38% was found; only Ae. albopictus mosquitoes were positive. Conclusion: Local strains of Wolbachia were detected and have the potential to be applied as a biological method for vector control.

Resumen: Objetivo: Evaluar la presencia de Wolbachia en poblaciones de campo de Aedes spp. en cementerios del Sur de México. Material y métodos: Se seleccionaron seis cementerios como sitios de colecta para las poblaciones silvestres de Aedes albopictus y Ae. aegypti, en la región del Soconusco, Chiapas, durante la época de lluvias 2015. Se determinó la infección por Wolbachia en hembras individuales por PCR. Resultados: Se obtuvo una infección de 38% por Wolbachia en Ae. albopictus. Conclusión: Existen cepas locales de Wolbachia en los mosquitos y poseen el potencial de aplicarse como medida de control biológico de vectores.

Prevention and control of Aedes transmitted infections in the post-pandemic scenario of COVID-19: challenges and opportunities for the region of the Americas

The coronavirus disease of 2019 (COVID-19) pandemic challenges public health systems around the world. Tropical countries will face complex epidemiological scenarios involving the simultaneous transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with viruses transmitted by Aedes aegypti. The occurrence of arboviral diseases with COVID-19 in the Latin America and the Caribbean (LAC) region presents challenges and opportunities for strengthening health services, surveillance and control programs. Financing of training, equipment and reconversion of hospital spaces will have a negative effect on already the limited resource directed to the health sector. The strengthening of the diagnostic infrastructure reappears as an opportunity for the national reference laboratories. Sharing of epidemiological information for the modeling of epidemiological scenarios allows collaboration between health, academic and scientific institutions. The fear of contagion by COVID-19 is constraining people with arboviral diseases to search for care which can lead to an increase in serious cases and could disrupt the operation of vector-control programs due to the reluctance of residents to open their doors to health personnel. Promoting intense community participation along with the incorporation of long lasting innovations in vector control offers new opportunities for control. The COVID-19 pandemic offers challenges and opportunities that must provoke positive behavioral changes and encourage more permanent self-care actions.

Health education in Aedes aegypti: case study / Educación en salud en torno al Aedes aegypti: un reporte de experiencia / Educação em saúde sobre o Aedes aegypti: relato de experiência

ABSTRACT Objectives: Reporting the experience of health education regarding Aedes aegypti in the Federal District. Methods: This is a case report, with descriptive approach, about the experience of nursing practice with education actions against the Aedes aegypti in communities of the Federal District, carried out between 2015 and 2018. Subjects of the research were undergraduate students in nursing, healthcare professionals, and the community. Results: There have been 24 educational interventions against Aedes aegypti, adapted to the needs of each population, using a "giant" sculpture of the mosquito, theater performances, lectures, booklets, and home visits. Conclusions: The project trained teachers, healthcare professionals, graduate students in nursing, and the community through the empowerment of this population, aiming at combating the Aedes aegypti vector.

RESUMEN Objetivos: Reportar la experiencia en torno a la educación en salud relacionada con el Aedes aegypti en el Distrito Federal (Brasil). Métodos: Se trata de un reporte de experiencia, de abordaje descriptivo, sobre la vivencia de la práctica de enfermería con acciones educativas contra el Aedes aegypti en comunidades del Distrito Federal, realizado en el período entre 2015 y 2018. Participaron en este estudio los estudiantes del grado en enfermería, los profesionales de los servicios de salud y la comunidad. Resultados: Se realizaron 24 acciones educativas contra el Aedes aegypti, las cuales se adaptaron a las necesidades de cada público y se utilizó una escultura "gigante" del mosquito, presentaciones de teatro, charlas, cartillas y visitas domiciliarias. Conclusiones: El proyecto capacitó a los docentes, a los profesionales de salud, a los estudiantes de grado en enfermería y a la comunidad, por medio del empoderamiento para combatir el vector Aedes aegypti.

RESUMO Objetivos: Relatar a experiência sobre educação em saúde em relação ao Aedes aegypti no Distrito Federal. Métodos: Trata-se de um relato de experiência, com abordagem descritiva, sobre a vivência da prática de enfermagem com ações educativas contra o Aedes aegypti em comunidades do Distrito Federal, realizada entre 2015 a 2018. Os sujeitos da pesquisa foram os graduandos de enfermagem, os profissionais dos serviços de saúde e a comunidade. Resultados: Realizaram-se 24 atuações educativas contra o Aedes aegypti, adaptadas às necessidades de cada público, utilizando-se uma escultura "gigante" do mosquito, apresentações de teatro, palestras, cartilhas e visitas domiciliares. Conclusões: O projeto capacitou docentes, profissionais de saúde, graduandos de enfermagem e comunidade por meio do empoderamento dessa população, com vistas ao combate ao vetor Aedes aegypti.

Un acercamiento al conocimiento de los hábitats larvarios de Aedes (Stegomyia) aegypti (Diptera: Culicidae) en el entorno doméstico en Jarabacoa, República Dominicana / An approach to larval habitats of Aedes (Stegomyia) aegypti (Diptera: Culicidae) in the domestic environment of Jarabacoa, Dominican Republic

Introducción: A nivel mundial, Aedes aegypti es el culícido más importante en cuanto a la transmisión de arbovirus de impacto en salud pública. Objetivo: Profundizar en los conocimientos ecológicos de Ae. aegypti en República Dominicana, a través de los recipientes o contenedores que utiliza para desarrollar sus formas preimaginales. Métodos: El estudio se extendió desde octubre a diciembre de 2017. Se muestrearon aleatoriamente 100 viviendas, en las que se revisaron todos los recipientes con potencialidad para albergar larvas y/o pupas de mosquitos, dentro y fuera del domicilio. Se cuantificó el tipo y total de cada depósito positivo según su ubicación en cada vivienda, para calcular el porcentaje de representatividad, junto al Índice Pupal por Depósitos específicos (IPDe) para cada receptáculo con pupas. Resultados: Se detectó presencia de Ae. aegypti en el 41 por ciento de las casas visitadas. De los 419 recipientes analizados, 74 resultaron positivos a larvas y/o pupas (17,66 por ciento). Se clasificaron 28 tipos de depósitos atendiendo a su función y material. Cuantitativamente, los depósitos permanentes fueron los más representativos con un 54,05 por ciento. Las mayores capturas se realizaron en el peridomicilio. El tanque plástico fue el más relevante, pues aportó el 28,37 por ciento del total de depósitos positivos, así como un elevado IPDe. Conclusiones: Los resultados evidencian elevados niveles de infestación en los domicilios de Jarabacoa que deben ser controlados a fin de disminuir el riesgo en la transmisión de arbovirosis. El control de los recipientes artificiales, como los contenedores desechables, los neumáticos y sobre todo los tanques de agua, es la piedra angular de cualquier esfuerzo para prevenir estas enfermedades(AU)

Introduction: Aedes aegypti is the most important culicid worldwide in terms of transmission of arbovirus infections of a high impact on public health. Objective: Broaden ecological knowledge about Aedes aegypti in the Dominican Republic, particularly about the containers and other sites where immature development occurs. Methods: The study extended from October to December 2017. One hundred households were randomly surveyed, checking all the containers with a potential to host mosquito larvae and/or pupae both inside and outside the house. Quantification was made of the type and total of positive containers according to their location in each household, to estimate the percentage of representativeness and the pupal index per container identified (PICI) when pupae were found in them. Results: Aedes aegypti was found to be present in 41 percent of the houses visited. Of the 419 containers analyzed, 74 were positive for larvae and/or pupae (17.66 percent). Containers were classified into 28 types according to their function and material. Quantitatively, permanent containers were the best represented with 54.05 percent. The largest captures were made in the area around the house. Plastic water tanks were the most relevant, with 28.37 percent of the total positive containers and a high PICI. Conclusions: Results show high levels of infestation in Jarabacoa households. These should be controlled to reduce the risk of arbovirus infection transmission. Control of artificial breeding sites, such as disposable containers, tires and especially water tanks, is the cornerstone of any effort to prevent these diseases(AU)

Precauciones en el uso de los espirales antimosquitos / Precautions in the use of anti-mosquitoes coils

La emergencia y reemergencia de enfermedades transmitidas por vectores (ETV) es un suceso de gran relevancia en la actualidad, debido al cambio climático, a la urbanización no planificada, y al incremento y variación de la temperatura global.1) El vector Aedes Aegypti, es el mayor responsable de algunas ETV como dengue, chikunguya, y zika.1 A nivel mundial, el virus del dengue provoca 390 millones de infecciones anuales,2 con un número estimado de 20 000 fallecidos.3 Latinoamérica, en los últimos años, viene experimentando un incremento dramático de casos y muerte por dengue.1 Esta situación, provoca que las personas intenten mantener las principales medidas de prevención contra estas enfermedades. La finalidad de los programas de prevención, vigilancia y control vectorial a nivel mundial, es controlar la proliferación del vector que causa el dengue y otras ETV. Las prácticas proporcionadas por la Organización Mundial de la Salud (OMS) incluyen el uso de espirales antimosquitos (EAM), que son ampliamente utilizados por la comunidad. Sin embargo, poco se dice sobre el riesgo para la salud que representan esos productos.1 Los EAM están compuestos por piretroides (pesticidas artificiales, eficaces contra diversos géneros de mosquitos) que, al hacer combustión, produce humo con partículas pequeñas (< 1 µm) que pueden ingresar hasta los alveolos y causar problemas pulmonares, vómitos, diarrea, convulsiones, parálisis, entre otros.4 El International Programme on Chemical Safety, en 1989, afirmó: si el uso de EAM se da bajo las condiciones de uso recomendadas, es poco probable que represente un peligro para la salud; de igual manera, la OMS clasifica a los piretroides como levemente peligrosos.5 Un estudio aplicado en ratas reveló que el uso del EAM está relacionado a un mayor riesgo de producir daño pulmonar severo,6 y otro estudio...(AU)

Presencia larval de Culex (Culex) interrogator (Dyar and Knab) (Diptera: Culicidae) en Cuba / Larval presence of Culex (Culex) interrogator (Dyar and Knab) (Diptera: Culicidae) in Cuba

Actualmente se conocen más de 3 500 especies de mosquitos y cada día se registran otras de importancia en la transmisión de enfermedades al hombre y los animales. El objetivo de este trabajo es registrar por primera vez la presencia larval de Cx interrogator en la provincia de Santiago de Cuba y en Cuba. Para ello se realizaron los muestreos larvarios en sitios de cría naturales y artificiales con frecuencia semanal durante el 2013-2017, según lo establecido por el Programa de Vigilancia y Control de otros culícidos para la provincia de Santiago de Cuba y adjunto al Programa de Control de Aedes aegypti y Aedes albopictus en Cuba. Las larvas se enviaron al Laboratorio Provincial de Entomología de Santiago de Cuba para su clasificación utilizando claves morfológicas. Posteriormente el material biológico fue enviado al Laboratorio de Referencia Nacional del Instituto de Medicina Tropical Pedro Kourí donde se verificó la identificación taxonómica. Culex interrogator fue colectado en los municipios Palma Soriano y San Luis en el 2013 en Santiago de Cuba, y Songo la Maya y II Frente en 2015 y 2017, respectivamente, todos pertenecientes a la provincia Santiago de Cuba. Los sitios de cría correspondieron a fosas sépticas, sótanos inundados debajo de edificios, lagunas de oxidación, pomos plásticos, zanjas, charcos y cañadas. Se encontró asociado en sitios de cría naturales con Culex nigripalpus, Culex quinquefasciatus y Anopheles albimanus. En conclusión, Cx interrogator constituye un nuevo registro para la entomofauna cubana, de ahí la importancia de ampliar los conocimientos sobre su distribución, asociación con otras especies de culícidos y posible rol en la transmisión de enfermedades al hombre(AU)

Nowadays there are more than 3 500 known species of mosquitoes and everyday are registered some more of importance in disease transmission to men and animals every day. The aim of this study is to register for the first time larval presence of Cx. interrogator in Santiago de Cuba province and in Cuba. In this regard, larval sampling was carried out by the established Surveillance and Control Program of other mosquitoes in Santiago de Cuba province and attached to the Control Program of Aedes aegypti and Aedes albopictus in Cuba; its was carried out in natural and artificial breeding sites with weekly frequency during 2013-2017. The larvae were sent to the Provincial Laboratory of Enthomology of Santiago de Cuba for classification using morphological keys. Subsequently, the biological material was sent to the National Reference Laboratory of Pedro Kourí Institute where the taxonomic identification was verified. Culex interrogator was collected in Palma Soriano and San Luis municipalities in 2013, in Santiago de Cuba, and Songo la Maya and II Frente in 2015 and 2017, respectively, all belonging to Santiago de Cuba province. The breeding sites were septic tanks, flooded basements under buildings, oxidation ponds, plastic bottles, ditches, puddles and streams. This mosquito was found in natural breeding sites associated to Culex nigripalpus, Culex quinquefasciatus and Anopheles albimanus. As a conclusion, it can be said that Cx. interrogator constitutes a new registry for Cuban entomofauna, hence the importance of expanding knowledge about its distribution, association with other culicid´s species and its possible role in the transmission of diseases to man(AU)

Entomopathogenic fungi and their potential for the management of Aedes aegypti (Diptera: Culicidae) in the Americas

Classical biological control has been used extensively for the management of exotic weeds and agricultural pests, but never for alien insect vectors of medical importance. This simple but elegant control strategy involves the introduction of coevolved natural enemies from the centre of origin of the target alien species. Aedes aegypti - the primary vector of the dengue, yellow fever and Zika flaviviruses - is just such an invasive alien in the Americas where it arrived accidentally from its West African home during the slave trade. Here, we introduce the concept of exploiting entomopathogenic fungi from Africa for the classical biological control of Ae. aegypti in the Americas. Fungal pathogens attacking arthropods are ubiquitous in tropical forests and are important components in the natural balance of arthropod populations. They can produce a range of specialised spore forms, as well as inducing a variety of bizarre behaviours in their hosts, in order to maximise infection. The fungal groups recorded as specialised pathogens of mosquito hosts worldwide are described and discussed. We opine that similar fungal pathogens will be found attacking and manipulating Ae. aegypti in African forests and that these could be employed for an economic, environmentally-safe and long-term solution to the flavivirus pandemics in the Americas.

Toxicity of Cry2 proteins from Bacillus thuringiensis subsp. thuringiensis strain T01-328 against Aedes aegypti (Diptera: Culicidae) / Toxicidade das proteínas Cry2 do Bacillus thuringiensis subsp. thuringiensis T01-328 contra Aedes aegypti (Diptera: Culicidae)

Bacillus thuringiensis subsp. israelensis has been used to control the Aedes aegypti (Diptera: Culicidae) mosquito larvae, the vector of virus diseases such as dengue, Chikungunya and Zika fever, which have become a major public health problem in Brazil and other tropical countries since the climate favors the proliferation and development of the transmitting vector. Because B. thuringiensis has shown potential for controlling insects of the Diptera order, this work aimed at testing the Bacillus thuringiensis subsp. thuringiensis strain T01-328 and its proteins Cry2Aa and Cry2Ab for control A. aegypti and at comparing the results to the B. thuringiensis subsp. israelensis specific dipteran strain. To this end, bioassays using spore-crystal of both strains, and Cry2Aa and Cry2Ab proteins from the heterologous expression in Escherichia coli, were performed against A. aegypti larvae. The results showed that the B. thuringiensis thuringiensis ­T01-328 has insecticidal activity against the larvae, but it is less toxic than B. thuringiensis subsp. israelensis. Cry2Aa and Cry2Ab proteins expressed heterologously were effective for controlling A. aegypti larvae. Therefore, the results indicate that the Cry2Aa and Cry2Ab proteins of the B. thuringiensis thuringiensis T01-328 can be used as an alternative to assist in the control of A. aegypti.(AU)

Bacillus thuringiensis subsp. israelensis vem sendo empregada no controle do díptero Aedes aegypti, vetor do vírus causador de doenças como dengue, febre Chikungunya e Zika, que se tornou um dos grandes problemas de saúde pública no Brasil e em outros países de clima tropical, que favorece a proliferação e o desenvolvimento do transmissor. Em virtude do potencial de B. thuringiensis no controle de dípteros, a proposta deste trabalho foi testar as proteínas Cry2Aa e Cry2Ab da linhagem de Bacillus thuringiensis subsp. thuringiensis T01-328 no controle de A. aegypti, em comparação à linhagem díptero específica B. thuringiensis subsp. israelensis. Para tanto, foram realizados bioensaios com larvas de A. aegypti com o esporo-cristal de ambas as linhagens, bem como com as proteínas Cry2Aa e Cry2Ab com expressão heteróloga em Escherichia coli. A linhagem B. thuringiensis thuringiensis T01-328 apresentou atividade inseticida contra as larvas, porém foi menos tóxica que a B. thuringiensis subsp. israelensis. As proteínas Cry2Aa e Cry2Ab expressas de forma heteróloga foram eficazes no controle de A. aegypti. Os resultados obtidos sugerem as proteínas Cry2Aa e Cry2Ab da linhagem B. thuringiensis thuringiensis T01-328 como alternativas para contribuir no controle do A. aegypti.(AU)

El clima organizacional, un aspecto importante a tener en cuenta en los trabajadores del grupo de control de vectores / The organizational climate as an important aspect to be taken into account in workers of the vector control groups

La investigación sobre el clima organizacional, se constituye en un proceso necesario para tomar decisiones ante problemas que puedan limitar el desempeño de una organización y de manera especial, en aquellas que deben asumir de forma exitosa, sensibles y complejas tareas,1,2 por lo que se hace necesario la evaluación del mismo en los grupos de control de vectores, es decir, a los trabajadores de la llamada campaña antiaegypti. Cuando los trabajadores del grupo perciben un clima organizacional no satisfactorio trae, como consecuencia que los resultados de su trabajo no sean favorables, por lo que, los operarios durante la realización de su labor pueden cometer fraude y este a su vez convertirse en un problema medioambiental, ya que al no identificar los riesgos detectados en la comunidad y no cumplir con lo establecido según las funciones de trabajo por el cargo que desempeñan, contribuye a la proliferación del mosquito y a elevarse los índices de infestación. Se conoce que el Ministerio de Salud Pública de Cuba se encuentra en un proceso de reorganización institucional y el avance hacia el desarrollo de la gestión de recursos humanos, pero esto solo es posible en la medida en que cambie la cultura organizacional que sustente la nueva dirección y organización institucional...(AU)

Effects of environment, dietary regime and ageing on the dengue vector microbiota: evidence of a core microbiota throughout Aedes aegypti lifespan

Abstract Mosquito midgut microbiota is a key component of vector competence, as gut bacteria can disturb pathogen development. In this study, we addressed the microbiota composition of Aedes aegypti during its lifespan, under field conditions. We also investigated the possible effects of environment, dietary regime and ageing on the gut community composition. We employed culture independent and dependent approaches to characterise vector microbiota. There was evidence of a lifelong stable core microbiota after mosquitoes were released into an urban settlement, where they presumably fed on a range of vertebrate hosts and carbohydrate sources. This core was formed mainly of bacteria belonging to the genera Pseudomonas, Acinetobacter, Aeromonas and Stenotrophomonas and to the families Oxalobacteraceae, Enterobacteriaceae and Comamonadaceae. We showed that both dietary regime and age were associated with the abundance of some bacterial groups in the Ae. aegypti microbiota. The majority of the bacterial groups we identified have been detected in the midgut of Ae. aegypti from laboratory and wild populations, indicating a possible core microbiota associated with this mosquito species. Our findings suggest that Ae. aegypti harbours a stable bacterial community during its adult life, similar to mosquito populations from distinct geographic areas, which may be further explored for arbovirus biocontrol strategies.

Índices de infestación aedica e identificación de conocimientos, actitudes y prácticas sobre dengue en llanterías del Departamento del Atlántico, Colombia / Aedes aegypti larval infestation index and identification of awareness, attitudes and practices related to Dengue in tire shops in Atlántico, Colombia

Objetivo Identificar los conocimientos, actitudes y prácticas sobre dengue en propietarios y trabajadores de llantería, así como los niveles de infestación del vector en llanterías del Departamento del Atlántico. Métodos Se realizó un estudio tipo descriptivo. Las variables se describieron a partir de porcentajes y medidas de tendencia central y dispersión. Se calculó el índice de infestación larvario para llanterías y el índice de depósitos en cada uno de los municipios muestreados. Se visitaron e inspeccionaron 111 llanterías; el 26,1 % (29/111) de estas se encontraron positivas para formas larvarias del vector Ae. aegypti. Los municipios de Piojó, Santo Tomas, Santa Lucia, Sabanagrande y Luruaco presentaron los índices de infestación larvaria en llanterías más altos (IIL: 50-100 %). Resultados Con respecto al dengue, el 90,9 % de los entrevistados lo consideró un problema para ellos y sus familias. El 94,6 % conoce que es transmitido por mosquitos; el 91,1 % conoce a la larva del vector como "sarapico", el 3,6 % como "gusarapo". El 98,2 % consideró que existe una relación entre la larva y el mosquito Ae. aegypti. El 100 % reconoce las llantas como un criadero para el mosquito. El 85,7 % consideró la fiebre como el síntoma más frecuente, el 83% manifestó asistir al puesto de salud para curar la enfermedad. El 90,8 % arroja las llantas no utilizables como basura. Conclusión En la población estudiada existen buenos conocimientos acerca del dengue y su vector; sin embargo, existen problemas de actitudes y prácticas para su prevención.(AU)

Objective To identify the awareness, attitudes and practices related to dengue in owners and workers of tire ships, as well as the levels of mosquito infestation in tire shops in Atlántico department - Colombia. Methods We conducted a descriptive study. The variables were described as percentages and measures of central tendency and dispersion. Index of larval infestation and containers were calculated in each of the municipalities studied. We visited and inspected 111 tire shops. 26.1 % (29/111) of these were found positive for Ae. aegypti larvae. The municipalities of Piojó, Santo Tomás, Santa Lucia, Sabanagrande and Luruaco were characterized by a higher larval infestation index. Results Regarding dengue, 90.9 % of respondents considered it a problem for them and their families. 94.6 % know that is transmitted by mosquitoes. 91.1 % know the vector larvae under the name "sarapico", 3.6 % as "gusarapo". 98.2 % felt that there is a relationship between the larva and Ae. aegypti mosquito. 100 % of participantes recognized tires to be a breeding for mosquitoes. 85.7% believed fever to be the most common symptom. 83 % reported accessing the health post to cure the disease. 90.8 % throw out unusable tires as if they were garbage. Conclusion In the population studied, there is good awareness of dengue and its vector. Nevertheless, there are problems related to attitudes and prevention practices.(AU)

Relación inter específica de Aedes albopictus (Diptera: Culicidae) con especies de culícidos en La Habana, Cuba / Interspecific relationship between Aedes albopictus (Diptera: Culicidae) and Culicidae species in Havana, Cuba

INTRODUCCIÓN: Aedes aegypti y Aedes albopictus vectores reconocidos de dengue son consideradas especies invasivas que están ampliamente distribuidas en zonas tropicales y parte de regiones templadas del planeta. OBJETIVOS: determinar la relación inter específica de Ae. albopictus con las comunidades de mosquitos de la provincia de La Habana en dos períodos de tiempo, 1995 -1999 y 2010-2012. MÉTODOS: se utilizaron los registros anuales de las muestras larvarias de mosquitos del laboratorio de Entomología de la provincia La Habana que forma parte del Programa Nacional de Control de Ae. aegypti. RESULTADOS: se determinó una coexistencia entre Ae. albopictus y Ae. aegypti al igual que con Culex quinquefasciatus favorecido en el caso de la primera por la fuerte presión con insecticida a que esta sujeta Ae. aegypti durante todo el año y con la segunda por la tolerancia fisiológica a los insecticidas que posee y ser considerada una especie oportunista, mientras que fue evidente el desplazamiento de Aedes mediovittatus por Ae. albopictus en los sitios de cría. CONCLUSIONES: se espera que continúe la coexistencia entre Ae. albopictus y Ae. aegypti en la provincia La Habana debido al ciclo estacional lluvia-seca presente en Cuba, la disponibilidad de criaderos existente producto de deficiencias en el saneamiento ambiental y problemas en el abasto de agua además del control permanente sobre Ae. aegypti que influye solo parcialmente en las poblaciones de Ae. albopictus.

INTRODUCTION: Aedes aegypti and Aedes albopictus recognized dengue vectors are considered invasive species that are widely distributed in tropical and temperate regions of the planet. The current distribution of the two Aedesmosquitoes overlap and are affected by interspecific larval competition in their container habitats. OBJECTIVE: to determine the interspecific relationship of Ae. albopictus with mosquitoes communities in Havana province in Cuba in two time periods , 1995 -1999 and 2010-2012. METHODS: annual records of mosquito larval samples from Entomology Laboratory Havana province were used for this study. RESULTS: coexistence between Ae. albopictus and Ae. aegypti as well as with Culex quinquefasciatus was demonstrated favored in the case of the first by strong insecticide pressure is subject Ae. aegypti throughout the year and the second by be considered an opportunistic species and the physiological tolerance to insecticides reported for it, whereas replacement of Ae. mediovittatus by Ae. albopictus was observed. CONCLUSIONS: our study demonstrated the coexistence between Ae. albopictus and Ae. aegypti in Havana province favored by the rainy - dry seasonal cycle present in Cuba , the availability of existing breeding sites product sanitation deficiencies and problems in the water supply, in addition to the permanent control of Ae. aegypti that only influencing populations of Ae. albopictus partially.

Depósitos observados con larvas de Aedes aegypti durante el uso operacional del biolarvicida Bactivec / Aedes aegypti larvae found in reservoirs during the operational use of Bactivec biolarvicide

Introducción: la determinación de los sitios de cría de Aedes aegypti constituye un factor de importancia para la aplicación de estrategias de control. Objetivo: identificar los depósitos utilizados por Aedes aegypti durante el período de uso operacional del biolarvicida Bactivec en el municipio Mariel. Métodos: de mayo 2008-2009, durante el período operacional del biolarvicida Bactivec, se realizó la búsqueda de criaderos positivos al culícido en áreas urbanas y semiurbanas de los consejos populares Boca/Mojica/Henequén, Mariel, Sabana/Zayas, Quiebra Hacha y Cabañas. Se identificaron todos los recipientes positivos al vector en las áreas en las que fueron colectados, se determinó el porcentaje de participación de cada tipo de recipiente en relación con el total de muestras positivas. Resultados: se identificaron 35 tipos de depósitos utilizados como sitio de cría del culícido. Los recipientes no útiles eliminables representaron el 54,28 porciento, los de almacenamiento de agua 14,29 porciento y los útiles 11,43 porciento; la presencia del vector del dengue en criaderos naturales y aguas contaminadas fue de 8,57 porciento. Conclusiones: los depósitos no útiles resultaron los más utilizados por el culícido para la puesta, seguido por los de almacenamiento de agua, los cuales se trataron con el biolarvicida. Se destaca la presencia de Aedes aegypti en aguas contaminadas, que también fueron tratadas con Bactivec

Introduction: the detection of breeding sites of Aedes aegypti is an important factor for the implementation of control strategies. Objective: to identify the reservoirs where Aedes aegypti mosquito was observed during the period of operational use of Bactivec larvicide in Mariel municipality. Methods: during the period of operational use of Bactivec biolarvicide from May 2008 to 2009, breeding sites positive for this mosquito were searched for in urban and semiurban areas of the people's councils Boca/Mojica/Henequen, Mariel, Sabana/Zayas, Quiebra Hacha y Cabanas. All the positive reservoirs were identified in those areas where they were collected and the percentage of involvement of each type of reservoir with respect to the total amount of positive samples was estimated. Results: thirty five types of reservoirs used as the breeding site of the mosquito were identified. The useless disposable reservoirs accounted for 54.28 percent, water storage reservoirs for 14.29 and the useful ones for 11.43 percent. The presence of the dengue vector in natural breeding sites and in polluted waters reached 8.57 percent. Conclusions: the useless reservoirs turned to be the most used by the Culicidae for egg-laying, following by the water storage ones which were treated with biolarvicide. Aedes aegypti was heavily present in polluted waters, which were also treated with Bactivec

Influencia de factores bióticos sobre la eficacia de Bacillus thuringiensis var. israelensis contra Aedes aegypti (Diptera: Culicidae) / Influence of biotic factors on the efficacy of Bacillus thuringiensis var. Israelensis against Aedes aegypti (Diptera: Culicidae)

Introducción: Bacillus thuringiensis H-14 ha mostrado alta eficacia sobre las larvas de Aedes aegypti, pero su efectividad puede ser influida por numerosos factores. El conocimiento de estos es de gran importancia porque permite optimizar los parámetros de aplicación en condiciones reales, para garantizar la eficiencia de los tratamientos y reducir el impacto ambiental. Objetivo: evaluar la influencia de los factores bióticos sobre la eficacia de Bacillus thuringiensis H-14 contra las larvas de Aedes aegypti. Métodos: se realizó un estudio experimental mediante bioensayos de laboratorio, siguiendo la metodología de la Organización Mundial de la Salud. Se evaluó la influencia de la disponibilidad de alimento, densidad y estadio larvario sobre la eficacia de Bacillus thuringiensis H-14 para Aedes aegypti. Se utilizó un biolarvicida comercial (Bactivec, Labiofam) y una cepa de referencia de Aedes aegypti (Rockefeller). Resultados: la eficacia de Bacillus thuringiensis H-14 fue menor en la medida en que avanzó la densidad y el estadio de desarrollo larvario, lo que puede estar en relación con la conducta de alimentación y la disponibilidad del principio activo. La presencia abundante de alimento también limita la eficacia por un efecto de competencia. Conclusiones: la eficacia de Bacillus thuringiensis H-14 se afectó por la disponibilidad de alimento, el estadio de desarrollo y la densidad larvaria, por lo que debe tenerse en cuenta esto para las aplicaciones del biolarvicida en el terreno.

Introduction: Bacillus thuringiensis H-14 has shown high efficacy on Aedes aegypti larvae. But a number of factors could affect its effectiveness. Knowing these factors is of vital importance for improving the application parameters in real conditions in order to guarantee the treatment's efficiency and to reduce environmental impact. Objective: to evaluate the influence of some biotic factors on Bacillus thuringiensis H-14 efficacy against Aedes aegypti (Rockefeller). Methods: an experimental study was conducted following the WHO guidelines. The influence of the food availability, the larval density and the larval staging was evaluated on laboratory bioassays. A commercial Bacillus thuringiensis H-14 formulation against a reference Aedes aegypti strain was used. Results: the efficacy of Bacillus thuringiensis H-14 decreased in a linear manner with increasing larval density and development stage. This could be related to food intake and availability of the active principle. Competition in food intake resulted in lower efficacy of Bacillus thuringiensis H-14 applications. Conclusions: the Bacillus thuringiensis H-14 efficacy was affected for the availability of food, the larval development stage and the larval density, so all this should be borne in mind when applying the biolarvicide in situ.

High prevalence and lack of diversity of Wolbachia pipientis in Aedes albopictus populations from Northeast Brazil

The use of Wolbachia as a tool to control insect vectors has recently been suggested. In this context, studies on the prevalence and diversity of this bacterium in wild populations are relevant. Here, we evaluated the diversity of two Wolbachiagenes (ftsZ and wsp) and the prevalence of this endosymbiont in wild Aedes albopictus. Using semi-nested polymerase chain reaction, our results showed that 99.3 percent of the individuals were superinfected with Wolbachia. In regards to genetic diversity, the two genes showed no variation within or among mosquito populations. An analysis of other Wolbachia markers may help to clarify the relationship between insect and endosymbiont.

Avaliação de parâmetros moleculares para vigilância entomológica do aeds (stegomyia)aegypti ( Linnaeus, 1762) / Evaluation of molecular parameters for entomological surveillance of AEDs (Stegomyia) aegypti (Linnaeus, 1762)

Apesar do combate recorrente ao mosquito vetor da dengue, o Aedes aegypti, mais de 80% dos estratos da cidade de Salvador-BA apresentam condição de alerta ou risco de surto de dengue. Visto que as abordagens tradicionais para controle do mosquito vetor da dengue não têm produzido os efeitos esperados, o presente estudo avaliou parâmetros moleculares para vigilância entomológica do A. aegypti utilizando ferramentas de geotecnologia e de genética de populações como forma de apoiar o trabalho de campo e ações integradas das instâncias responsáveis pelo controle da dengue. O desenho do estudo apresentou um componente transversal, descrevendo dados sobre a genética de população de larvas de A. aegypti coletadas em Salvador e amostras controle coletadas no ano de 2009 em Jacobina e Vitória da Conquista, além da cepa Rockfeller, e um longitudinal, sobre amostras de quatro áreas (Plataforma, Itapagipe, Tancredo Neves e Itapuã) durante quatro ciclos do LIRAa Salvador entre 2007 a 2009. O DNA de cada larva foi isolado pelo método DNAzol® e genotipado por 5 marcadores SSR através da técnica de PCR e eletroforese capilar. A distribuição espacial dos criadouros foi realizada utilizando-se ortofotos pelo programa Arcview v. 9.3. Para a análise da diferenciação populacional e teste de hipótese foram utilizados os programas GenePop, GenAlEx e Spade, e para inferência populacional utilizamos o programa structure. Os marcadores encontraram-se, em geral, em equilíbrio de H-W e comportaram-se como independentes. Quando utilizamos a estatística Φpt e RST foi possível discriminar significantemente (p<0,05) populações geneticamente diferenciadas de A. aegypti a nível de município, áreas do município de Salvador e estratos pertencentes a estas áreas. O programa structure indicou K igual a 2 populações como ideal para representar os dados, considerando a população de Salvador uma miscigenação de populações de A. aegypti de outras regiões do estado. Os resultados do estudo longitudinal mostraram uma diferenciação entre os ciclos de 2008.3 e 2009.4. As medidas de Ne variaram consideravelmente por área e ciclo evidenciando o efeito de gargalo de garrafa em diferentes períodos em cada área, apesar de não haver correlação com o IIP. A partir dos resultados obtidos, concluímos que o controle vetorial produz alterações sobre a estrutura populacional do A. aegypti, mas que não são efetivas. O uso do georreferenciamento e de informações genéticas do vetor poderiam contribuir para a definição das áreas de abrangência das populações do A. aegypti e para a tomada de decisões a respeito do manejo do tratamento.

Atividade tóxica de isolados de Bacillus Thuringiensis a larvas de Aedes Aegypti (l.) (diptera: culicidae) / Toxic activity of Bacillus Thuringiensis isolates to Aedes Aegypti (l.) (diptera: culicidae) larvae

Aedes aegypti (L.), the main vector of dengue fever in Brazil, has been controlled with the use of massive chemical products, contributing to the development of resistance and decreasing the insect control efficiency. The control of dipterans with bioinsecticides based on Bacillus thuringiensis has been satisfactory, due to the production of insecticidal proteins denominated Cry (crystal), Cyt (cytolytic) toxins and Chi (chitinase), and to the synergistic effects among them. The present work aimed to select B. thuringiensis isolates efficient against A. aegypti larvae. A bacterial collection containing 1,073 isolates of B. thuringiensis, obtained from different locations of Brazilian territory, had the DNA isolated and submitted to PCR amplifications using specific primers for cry4Aa, cry4Ba, cry11Aa, cry11Ba, cyt1Aa, cyt1Ab, cyt2Aa and chi genes. For the LC50 and LC90 determination, the entomopathogenic isolates were evaluated by selective and quantitative bioassays. Only 45 isolates (4.2 percent) presented amplicons for the cry and cyt genes. The chi gene sequence was detected in 25 (54.3 percent) of those isolates. From the 45 isolates submitted to the selective bioassays, 13 caused 100 percent mortality of A. aegypti larvae. The identification of cry, cyt and chi genes of B. thuringiensis and the toxicity analysis on A. aegypti led to the selection of a set of isolates that have the potential to be used in the formulation of new bioinsecticides.

Studies on mosquito borne dieases in Egypt and Qatar

Mosquitoes identification, distribution and densities in representative Egyptian Governorates and five Qatarain Municipalities [Al Rayyan, Doha, Al Daayan, Al Khor and Al Zahakira and Al Shamal] were studied. In Qatar the larvae were Culex pipiens complex, C. univettatus, C. pusillus, Aedes caspies, Anopheles multicolor and A. stephensi. C. pipiens and C. univettatus were mainly in Al Rayyan, Doha, and Al Khor and Al Zahakira. C. pusillus was in Doha and Al Daayan while A. caspies was in Al Daayan and Al Shamal. Anopheles multicolor and A. stephensi were mainly in Al Shamal with low density in Al Rayyan [only in Ain- Khalid locution]. The Egyptian mosquitoes were C. pipiens, C. antennatus, C. thelerei, C. univittatus, C. perexiguus, C. poicilipes, C. pusillus, Aedes caspius, Ae. detritus, A. sergentii, A. pharoensis, A. multicolor, A. detail, A. algeriensis, A. tene-brosus, A. gambiae [formerly], A. superpictus, A. tarkhadi, A. hispaniola, A. rhodesiensis, A. stephensi, A. coustani and Culiseta longiareolata. As an example in Sharkia Governorate, larvae were C. pipiens [68.77%], Ae. caspius [15.75%], Culiseta sp. [=Theobaldia] and C. pusillus. In Greater Cairo, parts of Qualyoubia G., C. pipiens was the most dominant and the least was C. perexiguus. In parts of Giza G., C. pipiens was the most dominant and least was Cs. longiareolata. In Cairo G., C. pipiens was the most dominant and least was Ae. caspius. The overall in Greater Cairo was C. pipiens [61.74%], Cs. longiareolata [15.56%], Ae. caspius [15.3%], C. pusillus [4.0%] and C. perexiguus [3.16%]

Impact of larviciding with a Bacillus thuringiensis israelensis formulation, VectoBac WG, on dengue mosquito vectors in a dengue endemic site in Selangor State, Malaysia.

The field bioefficacy of a wettable granule (WG) formulation of Bacillus thuringiensis israelensis (Bti), VectoBac WG (Bti strain AM65-52) against dengue vectors, Aedes aegypti and Ae albopictus; was evaluated in a suburban residential area (TST) and in a temporary settlement site (KB) in the state of Selangor, Malaysia. Pre-control ovitrap surveillance of the trial sites indicated a high population of both types of Aedes mosquitoes. The populations were monitored continuously by weekly ovitrapping. Bti was sprayed biweekly at a dosage of 500 g/ha by using a mist-blower. The spray application was targeted into outdoor larval habitats. If required, Bti formulation was also applied directly into indoor water-holding containers at 8 g/1,000 l. Based on ovitrap surveillance, a significant reduction in Aedes populations was evident 4 weeks after initiating the first Bti treatment. The ovitrap index (OI) and the larvae density decreased drastically in both trial sites. In TST, the indoor OI was significantly reduced from 57.50 +/- 7.50% to 19.13 +/- 5.49% (p<0.05), while the outdoor OI decreased from 38.89 +/- 11.11% to 15.36 +/- 5.93%. In KB, similarly, the OI was significantly reduced by more than half, from 66.66 +/- 6.67% to 30.26 +/- 2.99% (p< 0.05). In all cases, the reduction in OI was paralleled by reduction in larval density.