What is the optimal In2Care stations density to achieve Aedes aegypti population reduction in a dengue endemic setting?

<b>Background:</b> Autodissemination traps are among the most innovative strategies for suppressing mosquito vector populations. These traps are particularly effective against <i>Aedes aegypti</i> due to the species' skip oviposition behavior, where eggs from a single clutch are distributed across multiple breeding sites. Evaluating the efficacy of In2Care stations under field conditions, especially in a dengue-endemic setting, is crucial for understanding their potential impact.<b>Methodology/Principal Findings:</b> A total of 3,250 In2Care stations were deployed in Goiânia, the 10th largest city in Brazil, with an estimated population of 1.45 million. The field study lasted 14 months, with each station serviced bi-monthly. To assess the impact of In2Care, 318 ovitraps were installed and inspected weekly to measure changes in the number of positive ovitraps and the average number of eggs laid by <i>Ae. aegypti</i> females in intervention areas compared to control neighborhoods. Over the course of the study, 666,204 eggs were sampled.<b>Conclusions/Significance:</b> The density of In2Care stations varied across neighborhoods, ranging from 220 to 555 stations per km². In the Tremendão area, which had the highest density (~555 stations per km²), the Ovitrap Positivity Index (OPI) decreased from 56.9% to 31.5%, while the average number of eggs per positive paddle dropped from 41.2 to 18.1—representing a 56% reduction in egg counts. Conversely, in SL Universitário, which had the lowest station density (~220 stations per km²), no significant effect was observed. These results demonstrate that In2Care stations can effectively suppress <i>Ae. aegypti</i> populations over large geographic areas, with efficacy likely influenced by trap density.