Programmatic implementation of Ovicol ovitraps for Aedes spp. control in Colombia: operational adherence,...

The global expansion of Aedes aegypti and Aedes albopictus mosquitoes has intensified arboviral epidemics, generating annual socio-economic losses exceeding 2 billion US dollars, mainly in the Americas. The desiccation-resistant egg stage plays a key role in mosquito persistence and spread, yet this developmental stage remains insufficiently targeted by current control strategies. In this context, the objective of this study was to evaluate the operational feasibility and effectiveness of a low-cost, handcrafted ovitrap (Ovicol) using two types of bioattractants, implemented by two territorial health entities (Entidades Territoriales de Salud [ETSs]) in Colombia, and to compare its performance with that of industrial autocidal gravid ovitraps (AGO) and BG-Sentinel (BGS) traps METHODS: Ovicol traps were baited with bird seed or molasses + yeast bioattractants. In Santa Marta, traps were installed in public areas (markets, cemeteries, sports complexes) using diflubenzuron as insecticide; in San José del Guaviare, the traps were deployed in buildings (hotels, schools, health centers) using a combination of diflubenzuron and Bacillus thuringiensis israelensis (BTi) as insecticide treatment. Data were analyzed through descriptive statistics, analysis of variance/chi-square test, nonparametric tests and spatial cluster detection.

In Santa Marta, 41,677 eggs (100% Ae. aegypti) were eliminated and inactivated in 5 weeks. The Oviposition Positivity Index (OPI) ranged from 40.6% to 74.5%, with up to 88% of traps lost to the study at one site due to vandalism. In Guaviare, Ovicol traps registered oviposition within 24 h and outperformed AGO in terms of Aedes detection (65.2% vs. 30.8%, respectively; r = 0.87; P < 0.001). The fermented bird seed attractant achieved higher positivity (Kruskal-Wallis H = 9.42; P = 0.009). Compared with BGS traps, Ovicol showed superior stability in the field, with BGS traps limited by ≥ 70% rate of electrical disconnection during weekends, and low concordance (kappa: - 0.17).

Ovicol is a cost-effective, operationally simple, and eco-sustainable tool for Aedes surveillance and control. By outperforming AGO and complementing BGS traps, Ovicol enhances spatiotemporal resolution for early microfocus detection and targeted response. Acting as a lethal trap, one diflubenzuron tablet (normally for 200 l) can treat approximately 800 Ovicol (0.25 L each), extending coverage to approximately 800 households and achieving an approximately 800-fold increase in larvicide efficiency. These findings support Ovicol's incorporation into national programs to promote sustainable, community-driven integrated vector management.