Urban populations of Aedes aegypti from central Argentina: micro-geographic genetic differentiation and estimation of effective dispersal by spatial autocorrelation

<i>Aedes aegypti,</i> the main vector of dengue and other arboviruses, was declared eradicated from Argentina in 1964; however, in 1987 it was detected again and nowadays it occurs in most of the country territory. To understand the transmission of vector-borne diseases, knowledge of the dispersal of vector populations is essential to evaluate the risk of pathogen transmission. We conducted a micro-geographic population genetic analysis of Ae. aegypti in 20 neighborhoods from Córdoba, the second largest city in Argentina, using 10 microsatellite loci. A marked genetic differentiation between population pairs was revealed using Weir and Cockerham’s θ and Bayesian approaches. The absence of an isolation by distance pattern might be due to the introduction of different genetic stocks through passive transport . Finally, spatial autocorrelation was significantly high for individuals separated by distances of up to 200 m, indicating that the effective dispersal would not exceed this range. The high levels of polymorphism and the genetic structure observed among populations in the city would result from the short range of movement of this vector and a continuous inflow of migrants from neighboring countries. These observations highlight the importance of knowing the genetic structure of <i>Ae. aegypti</i> populations and their dispersal patterns in order to implement vector control programs.<br>