Where does Aedes albopictus (Diptera: Culicidae) really breed in a Mediterranean residential area? Results from a field study in Valencia, Eastern Spain.

Since its introduction in Spain in 2004, Aedes albopictus has rapidly spread across the country. Its aggressive biting behaviour causes nuisance, limiting outdoor activities. Also, its role as a vector of several arboviruses implies a major public health risk, with several cases of autochthonous dengue having been reported nationwide over the past few years. Control strategies usually focus on interventions in breeding sites. As such, accurate knowledge of the main larval habitats becomes a major priority in infested areas. A detailed identification of breeding sites of Ae. albopictus was carried out in the outdoors of 60 residential properties during July-August 2022 in El Vedat de Torrent (Valencia, Eastern Spain), an area recently colonised by this species. A total of 1444 real and potential breeding sites were examined. The most abundant potential larval habitat were plant pot plates (6.48 units/house), although a low infestation level was found, both for larvae (2.06% positivity, x̄ = 30.5 larvae/container), and pupae (0.51%, x̄ = 2.5 pupae/container). A total of 7715 larvae and 205 pupae were found in a disused flooded water pool depuration system. Animal drinkers, buckets and irrigation water containers were found to be the most common positive containers. No statistical difference was observed among the different container materials. A general statistical increase of 1 larva per 11.7 ml of water in breeding sites was detected. Breeding sites of other species such as Culex pipiens (n = 2) and Culex modestus (n = 1) were also rarely found in this residential area. To our knowledge, this is the first aedic index study carried out in Europe, and it provides valuable information about the main domestic breeding habitats of Ae. albopictus, which can greatly improve control programmes.

Controladores biológicos para la reducción de índices aédicos / Biological controllers for the reduction of aedic indices

Ante la ausencia de vacunas eficaces para las arbovirosis transmitidas por el vector A. aegypti y la resistencia a insecticidas se hace necesario buscar alternativas, donde resalta el control biológico con el uso del larvicida microbiológico Bacillus thuringiensis var. israelensis (Bti). Como objetivo, se propuso determinar los índices aédicos y el uso de Bacillus thuringiensis israelensis como controlador biológico de Aedes aegypti en la localidad de Huánuco, Perú durante el segundo semestre de 2019. La investigación fue experimental de corte transversal con una muestra de 263 viviendas distribuidas en cinco bloques. Como instrumento se usó la observación y reporte de fichas a través de la inspección de cada vivienda en dos momentos, inicial y final, separadas por un lapso de 90 días. Para el análisis de los datos se usó estadística descripctiva a través de Epidat 3.0, obteniendo IA, IR e IB. Como resultado, de las 236 casas inspeccionadas, 51% (120/236) fueron no intervenidas y 49% (116/236) fueron intervenidas con Bacillus thuringiensis, de las casas no intervenidas (120/236) en la fase inicial 59% fueron positivas (con la presencia de algún estadío de A. aegypti) y en la fase final fue de 63%, por otra parte, en las casas intervenidas con Bacillus thuringiensis (CCB) (116/236) en la fase inicial 61% (71/116) estaban positivas y la fase final hubo un descenso a 32% (37/116). En conclusión, se sugiere que la aplicación de Bti constituye un componente adecuado para el manejo de poblaciones larvales de A. aegypti, en la ciudad de Perú(AU)

In the absence of effective vaccines for arboviruses transmitted by the vector A. aegypti and resistance to insecticides, it is necessary to look for alternatives, where biological control stands out with the use of the microbiological larvicide Bacillus thuringiensis var. israelensis (Bti). As an objective, it was proposed to determine the aedic indices and the use of Bacillus thuringiensis israelensis as a biological controller of Aedes aegypti in the town of Huánuco, Peru during the second half of 2019. The research was experimental cross-sectional with a sample of 263 homes distributed in five blocks. As an instrument, the observation and reporting of records was used through the inspection of each dwelling in two moments, initial and final, separated by a period of 90 days. For data analysis, descriptive statistics were used through Epidat 3.0, obtaining IA, IR and IB. As a result, of the 236 houses inspected, 51% (120/236) were not intervened and 49% (116/236) were intervened with Bacillus thuringiensis, of the houses not intervened (120/236) in the initial phase, 59% were positive (with the presence of some stage of A. aegypti) and in the final phase it was 63%, on the other hand, in the houses intervened with Bacillus thuringiensis (CCB) (116/236) in the initial phase 61% (71 /116) were positive and the final phase there was a decrease to 32% (37/116). In conclusion, it is suggested that the application of Bti constitutes an adequate component for the management of larval populations of A. aegypti, in the city of Peru(AU)