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Simple Summary: Household surveys of communities for potential oviposition containers by mosquito control teams offer effective mechanisms for reducing arbovirus transmission. Here, we combined standard community surveys with GIS mapping to identify premises with Aedes-positive containers and classify container types near the end of the dry season in Trinidad, West Indies. The entomological indices based on key containers (tanks, drums, tubs/basins/buckets) showed that two of the four locations surveyed were already at a high risk for arbovirus transmission going into the wet season. GIS mapping provided inspection teams with specific locations that had Aedes-positive containers and highlighted premises that were not accessible. This information can facilitate the identification of areas within communities that may be at greater risk and should be prioritized for future surveys and control efforts; it also highlights the need to inform and increase community participation. Dengue and other arboviruses remain a global threat, and enhanced efforts to control the mosquitoes that transmit them are urgently needed. A survey of potential manmade Aedes aegypti (L.) and Aedes albopictus (Skuse) oviposition containers was performed in four communities near the end of the typical dry season in 2018 in Trinidad, West Indies. The purpose was to conduct individual premise surveys and use GIS mapping to visualize premises within communities that had Aedes-positive containers, as this information could be used for the prioritization of mosquito control efforts in potential high risk areas as the wet season progressed. Accessible premises were surveyed following standard inspection protocols used by the Insect Vector Control Division (IVCD), Ministry of Health (MOH). The results indicated that two of the four locations would be at high risk for arbovirus transmission going into the wet season. The GIS mapping of premises with Aedes-positive containers facilitated the identification of potential hot spots for arbovirus transmission risk within communities that should be prioritized for enhanced monitoring and vector control efforts, emphasizing the need to increase community participation in standard surveys by IVCD. [ABSTRACT FROM AUTHOR]

Simple Summary: Mosquito-borne infectious diseases threaten millions of people worldwide, and it is critical that we identify new methods for controlling these insects. We recently developed a new class of mosquito insecticides that consists of yeasts which produce interfering RNA that is custom-designed to turn off mosquito genes yet does not hurt other organisms. Here, we test a newly optimized robust yeast strain which is suitable for industry-scale yeast production. Following heat inactivation and drying, the yeast was shipped to St. Augustine, Trinidad and Bangkok, Thailand, where it was evaluated in outdoor studies performed in tropical settings. The yeast effectively killed a variety of different types of mosquito larvae that died following yeast consumption. It could also be supplied to adult mosquitoes in a sugar bait solution, resulting in high levels of mosquito death. The yeast killed mosquitoes more quickly in outdoor experiments than in laboratory trials. These promising results indicate that yeast insecticides could one day be used globally as a new means of eco-friendly mosquito control and disease prevention. Eco-friendly new mosquito control innovations are critical for the ongoing success of global mosquito control programs. In this study, Sh.463_56.10R, a robust RNA interference (RNAi) yeast insecticide strain that is suitable for scaled fermentation, was evaluated under semi-field conditions. Inactivated and dried Sh.463_56.10R yeast induced significant mortality of field strain Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus larvae in semi-field larvicide trials conducted outdoors in St. Augustine, Trinidad, where 100% of the larvae were dead within 24 h. The yeast was also stably suspended in commercial bait and deployed as an active ingredient in miniature attractive targeted sugar bait (ATSB) station sachets. The yeast ATSB induced high levels of Aedes and Culex mosquito morbidity in semi-field trials conducted in Trinidad, West Indies, as well as in Bangkok, Thailand, in which the consumption of the yeast resulted in adult female mosquito death within 48 h, faster than what was observed in laboratory trials. These findings support the pursuit of large-scale field trials to further evaluate the Sh.463_56.10R insecticide, a member of a promising new class of species-specific RNAi insecticides that could help combat insecticide resistance and support effective mosquito control programs worldwide. [ABSTRACT FROM AUTHOR]

Simple Summary: Current mosquito control efforts are insufficient for preventing mosquito-borne illnesses. Attractive targeted sugar bait (ATSB) technology is an emerging mosquito control method that involves luring mosquitoes to feed on a sugar suspension containing a poison. Here, we comprehensively review the existing literature to evaluate the potential utility of ATSBs for mosquito control. We highlight milestones in the development of ATSBs, focusing on the selection of toxic ingredients and attractive components, methods of deployment, and efficacy studies. We discuss the potential utilization of ATSBs in combination with other control technologies and identify existing gaps in the ongoing development of this promising technology. We conclude that the deployment of ATSBs in integrated mosquito control programs will help address mosquito control challenges and prevent diseases that result from pathogens transmitted by mosquitoes. Due to the limitations of the human therapeutics and vaccines available to treat and prevent mosquito-borne diseases, the primary strategy for disease mitigation is through vector control. However, the current tools and approaches used for mosquito control have proven insufficient to prevent malaria and arboviral infections, such as dengue, Zika, and lymphatic filariasis, and hence, these diseases remain a global public health threat. The proven ability of mosquito vectors to adapt to various control strategies through insecticide resistance, invasive potential, and behavioral changes from indoor to outdoor biting, combined with human failures to comply with vector control requirements, challenge sustained malaria and arboviral disease control worldwide. To address these concerns, increased efforts to explore more varied and integrated control strategies have emerged. These include approaches that involve the behavioral management of vectors. Attractive targeted sugar baits (ATSBs) are a vector control approach that manipulates and exploits mosquito sugar-feeding behavior to deploy insecticides. Although traditional approaches have been effective in controlling malaria vectors indoors, preventing mosquito bites outdoors and around human dwellings is challenging. ATSBs, which can be used to curb outdoor biting mosquitoes, have the potential to reduce mosquito densities and clinical malaria incidence when used in conjunction with existing vector control strategies. This review examines the available literature regarding the utility of ATSBs for mosquito control, providing an overview of ATSB active ingredients (toxicants), attractants, modes of deployment, target organisms, and the potential for integrating ATSBs with existing vector control interventions. [ABSTRACT FROM AUTHOR]

Simple Summary: It is critical that we identify new methods of preventing mosquito-borne infectious diseases, which threaten millions of people worldwide. In this investigation, we describe characterization of a new insecticide that turns off the mosquito Iroquois (Irx) gene, which is required for mosquito survival. The pesticide is synthesized in yeast, which can be fed to adult mosquitoes in a sugar bait solution or to juvenile mosquitoes that eat the yeast when it is placed in water where mosquitoes breed. Although the yeast kills several different types of mosquitoes, it was not found to affect the survival of other types of arthropods that consumed the yeast. These results indicate that yeast insecticides could one day be used for environmentally friendly mosquito control and disease prevention. Concerns for widespread insecticide resistance and the unintended impacts of insecticides on nontarget organisms have generated a pressing need for mosquito control innovations. A yeast RNAi-based insecticide that targets a conserved site in mosquito Irx family genes, but which has not yet been identified in the genomes of nontarget organisms, was developed and characterized. Saccharomyces cerevisiae constructed to express short hairpin RNA (shRNA) matching the target site induced significant Aedes aegypti larval death in both lab trials and outdoor semi-field evaluations. The yeast also induced high levels of mortality in adult females, which readily consumed yeast incorporated into an attractive targeted sugar bait (ATSB) during simulated field trials. A conserved requirement for Irx function as a regulator of proneural gene expression was observed in the mosquito brain, suggesting a possible mode of action. The larvicidal and adulticidal properties of the yeast were also verified in Aedes albopictus, Anopheles gambiae, and Culexquinquefasciatus mosquitoes, but the yeast larvicide was not toxic to other nontarget arthropods. These results indicate that further development and evaluation of this technology as an ecofriendly control intervention is warranted, and that ATSBs, an emerging mosquito control paradigm, could potentially be enriched through the use of yeast-based RNAi technology. [ABSTRACT FROM AUTHOR]