Spatial distribution pattern of oviposition in the mosquito Aedes aegypti in relation to urbanization in Buenos Aires: southern fringe bionomics of an introduced vector

Abstract

The distribution of Aedes aegypti (L) (Diptera: Culicidae) oviposition in Buenos Aires City is spatially heterogeneous. Oviposition activity was monitored for a year with a grid of 279 traps at 850-m intervals that were serviced weekly. Geostatistics were used for the spatial analysis and generalized linear regression to model oviposition as a function of demographic and environmental variables. The proportion of weeks infested and the total number of eggs showed spatial continuity and were higher in areas that had higher densities of houses and were closer to industrial sites; they were lower in areas with higher human populations or higher densities of flats. When all sites were considered, the spatial structure showed a strong trend, but after regression, the residuals presented lower spatial dependence. When only infested sites were considered, the oviposition variables were spatially autocorrelated and the regression residuals showed little or no spatial dependence. The spatial pattern of Ae. aegypti oviposition in a highly urbanized city such as Buenos Aires seems to be related to the urbanization gradient. These urban environments might present different resource availability or continuity between patches of resources.

Modelización del efecto de la variabilidad climática local sobre la transmisión de dengue en Medellín (Colombia) mediante análisis de series temporales

“…La transmisión de la enfermedad es multicausal, y en ella intervienen diferentes factores entomológicos, socioeconómicos y climáticos (3,4). En particular, se ha evidenciado que estos últimos juegan un papel importante en la distribución espacial y temporal de la enfermedad (5,6).…”

Tire-breeding mosquitoes of public health importance along an urbanisation gradient in Buenos Aires, Argentina

“…Our findings are in accordance with the oviposition pattern of Ae. aegypti in Buenos Aires City described by Carbajo et al (2006); lower infestation levels were found in areas with higher human populations or higher densities of flats.…”

“…Within the Federal District, the spatial pattern of Ae. aegypti oviposition was associated with an urbanisation gradient (Carbajo et al 2006) and the presence of immatures at the microhabitat scale was related to shaded and vegetated surroundings (Vezzani et al 2005). However, these studies were restricted to highly urbanised areas and the knowledge of both mosquito vectors in small towns, as well as in used tires, is truly limited in the region.…”

Genetic structure of Aedes aegypti in the city of Córdoba (Argentina), a recently reinfested area

“…Sampling points were located more than 4 km apart, a distance much larger than the flight range of the species, but within residential neighbourhoods that had low human densities and consisted mostly of houses with gardens and backyards. In Buenos Aires (the capital city of Argentina), Carbajo et al (2006) found that oviposition activity was higher in areas with a larger proportion of houses and lower human density, compared to more urbanized areas with high-rise buildings and higher human density. A positive association was also found between oviposition and industrial sites, possibly due to a high density of water containers.…”