A scalable mass production cage (Aedes-MPC) for high-density Aedes albopictus rearing under operational SIT conditions

Aedes albopictus is a globally invasive mosquito species and a major vector of arboviruses including dengue, chikungunya, and Zika. Its rapid expansion in urban and peri-urban environments highlights the need for scalable and efficient vector control strategies. The sterile insect technique (SIT), based on the mass release of sterilised males, is a promising environmentally friendly approach, but its effectiveness depends on reliable mass-rearing systems. Although larval production and sex separation have been optimised, adult rearing remains a critical bottleneck for large-scale SIT implementation, as existing cage systems may involve labour-intensive handling, inefficient use of space, and limited flexibility for routine production. We developed a novel thermoformed plastic mass production cage (Aedes-MPC) integrating modular systems for feeding, pupal loading, and egg collection to simplify cage management and improve the scalability and egg productivity of adult mass rearing. A new Aedes-MPC (80 × 80 × 20 cm; 128 L) integrating modular systems for pupal loading, sugar and blood feeding, and egg collection was developed and tested under controlled mass-rearing conditions at the Centro Agricoltura Ambiente (Italy). Three European Aedes albopictus strains (Italy, Greece, Switzerland) were reared over one year using a standardized production schedule. A total of 150 cages were evaluated. Egg productivity, oviposition timing, cumulative output, and cycle duration were assessed across up to five oviposition cycles. Data were analysed using generalized linear models and repeated-measures GLM to test effects of strain origin, production cycle, and cage performance group. All cages completed at least three oviposition cycles, with 90.7 and 32.0% reaching four and five cycles, respectively. Egg production decreased linearly across successive cycles, while cumulative egg production expressed per day of cage operation followed a parabolic trend, peaking between the second and third cycles. Total egg production was significantly influenced by the number of oviposition cycles achieved ( p < 0.001), but not by strain origin. Productivity dynamics were consistent across all strains. Cages completing five cycles showed a shorter cumulative timing of egg collection and higher early productivity as compared to cages that ceased production earlier. The Aedes-MPC supported high and reproducible Ae. albopictus egg production across different strains under operational SIT conditions. Its modular design, high adult capacity, and simplified routine handling make it a promising option for medium- to large-scale production, with potential to improve space use and reduce labour associated with adult colony management. Further optimisation of feeding regimes and oviposition scheduling may further improve productivity and operational efficiency.