Field Effectiveness of Drones to Identify Potential Aedes aegypti Breeding Sites in Household Environments from Tapachula, a Dengue-Endemic City in Southern Mexico

Abstract

Aedes aegypti control programs require more sensitive tools in order to survey domestic and peridomestic larval habitats for dengue and other arbovirus prevention areas. As a consequence of the COVID-19 pandemic, field technicians have faced a new occupational hazard during their work activities in dengue surveillance and control. Safer strategies to monitor larval populations, in addition to minimum householder contact, are undoubtedly urgently needed. Drones can be part of the solution in urban and rural areas that are dengue-endemic. Throughout this study, the proportion of larvae breeding sites found in the roofs and backyards of houses were assessed using drone images. Concurrently, the traditional ground field technician's surveillance was utilized to sample the same house groups. The results were analyzed in order to compare the effectiveness of both field surveillance approaches. Aerial images of 216 houses from El Vergel village in Tapachula, Chiapas, Mexico, at a height of 30 m, were obtained using a drone. Each household was sampled indoors and outdoors by vector control personnel targeting all the containers that potentially served as Aedes aegypti breeding sites. The main results were that the drone could find 1 container per 2.8 found by ground surveillance; however, containers that were inaccessible by technicians in roofs and backyards, such as plastic buckets and tubs, disposable plastic containers and flowerpots were more often detected by drones than traditional ground surveillance. This new technological approach would undoubtedly improve the surveillance of Aedes aegypti in household environments, and better vector control activities would therefore be achieved in dengue-endemic countries.

Keywords: Aedes aegypti; Tapachula; breeding sites; drone; mosquito surveillance.

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1

Geographical representation of the study area, El Vergel neighborhood, north of Tapachula city and municipality, in the far southeast of Chiapas, Mexico. The black rectangles represent the study dwellings.

Figure 2

Drone images of larvae breeding sites on the roofs of houses in El Vergel, Tapachula, Chiapas, in (a) elevated storage tank; (b) tires; (c) others (puddles); (d) disposable plastic containers, (e) flowerpots and (f) plastic bucket & tubs.

Figure 3

Drone images of larvae breeding sites in outdoor (backyard) areas of houses in El Vergel, Tapachula, Chiapas, in (a) disposable plastic container; (b) plastic buckets and tubs; (c) cement washbasins (large); (d) WCs; (e) flowerpots; and (f) other (pools).