Eggsearcher Infodengue

This app is an initiative of the infodengue project.

The use of ovitraps for surveillance of natural populations of Aedes mosquitoes is a high-sensitivity, high-specificity method [refs] of extreme relevance for the study of such populations and their impact in the epidemiology of arboviroses they transmit, such as Dengue, Zika and Chikungunya, among many others [refs]. As for the many arborviroses transmitted by aedes mosquitoes there is no vaccine or other effective means of reducing infection, Control of the vector populations has been the most used tool to reduce transmission of these diseases. In order to control these populations we must first determine its spatio-temporal dynamics and the availability of good surveillance tools such as the ovitrap is fundamental for the study of such populations[refs].

Ovitraps are also a very cheap tool to construct and can be easily manufactured anywhere[refs] from basic components such as a small plastic flower pot, and a stick of wood or strip of cloth (see figure 1).

One of the major obstacles to the widespread use of the ovitrap as a continuous surveillance tool, is the labour cost of the operation of a sizeable grid of ovitraps. Ovitraps need to be manually checked approximately every week, with
the collection of the egg support (wood stick, or cloth). The egg support is take to a lab where a trained technician manually counts the eggs under a stereo microscope. There can be many hundreds or even thousands of eggs in single support making this task extremely time consuming and expensive, in terms of labour-hours. When working with large grids of ovitraps, comprising hundreds or thousands of traps, this limits the temporal sampling of the population to once every month or every two months. With the mosquito being an r-strategist, this slow sampling rate cannot capture the fine dynamics of their populations.

In this paper, we introduce an open-source hardware and software system aimed at making possible the deploy wide grids of ovitraps with a high sampling rate by speeding up the counting process and thus eliminating the use of microscopes and the many hours of highly skilled labor. By using our system, egg counting can be done on site, in a matter of seconds.