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Background Dengue fever, transmitted primarily by Aedes aegypti and Ae. albopictus, remains one of the most pervasive mosquito-borne diseases worldwide. In China, the mosquito oviposition trap (MOT) - based Aedes monitoring system has become a cornerstone for dengue prevention and control. However, during outbreaks, this system faces operational challenges because of its labour-intensive nature and time requirements, limiting its efficiency for rapid vector control assessment. Methods Based on the oviposition behavior of Ae. albopictus, a novel Improved Ovitrap (IMT) was designed, featuring a bucket-shaped body and a thermoplastic elastomer (TPE) oviposition band. Two field investigations were conducted in Guangzhou, Guangdong Province, China. Field Investigation 1 focused on continuous mosquito surveillance to evaluate the effectiveness of the IMT. Distance-incremental spatial autocorrelation analysis was performed to determine the monitoring radius of the IMTs, and suitable sampling fractions were estimated to identify the optimal sampling density. Field Investigation 2 aimed to compare the monitoring effectiveness of the IMT and the standard MOT for Ae. albopictus. Finally, an IMT-based surveillance strategy was proposed for local dengue epidemic control and was preliminarily implemented within case-area targeted intervention (CATI) practices. Results Our research established a significant positive correlation between the newly developed new Ovitrap Index (NOI) and the existing mosquito or oviposition positive index (MOI), which facilitated the creation of a IMT based surveillance strategy for dengue outbreak response. This optimized system recommends deploying six IMTs per standard 120,000 m2 CATI zone, maintaining continuous 24-hour monitoring cycles until official outbreak resolution, and implementing NOI threshold categories (0, 0-10, 10-20, 20-40, and ≥40) analogous to established MOI standards. Following successful implementation during three 2024 Guangdong CATI initiatives, this strategy has proven adaptable to complex urban environments while providing daily surveillance capabilities superior to those of conventional MOI-based systems. Conclusions In the present study, the IMT was developed and evaluated for field surveillance of Ae. albopictus mosquitoes. The core usage parameters of the IMT-based surveillance system, including the working radius and area deployment density, have been determined using systematic field investigations combined with mathematical modelling assessments. Furthermore, a novel strategy utilizing the IMT for evaluating the efficacy of integrated mosquito vector management in CATI during dengue outbreaks has been proposed. Preliminary results have confirmed the feasibility of using the IMT at outbreak sites, providing valuable support for CATI-based implementation. This innovative monitoring system offers an alternative solution and implementation strategy for conducting cost-effective surveillance of the dengue vector Ae. albopictus, as well as for evaluating the efficacy of integrated vector management during outbreaks. Graphical Abstract

Africa and the United States are both large, heterogeneous geographies with a diverse range of ecologies, climates and mosquito species diversity which contribute to disease transmission and nuisance biting. In the United States, mosquito control is nationally, and regionally coordinated and in so much as the Centers for Disease Control (CDC) provides guidance, the Environmental Protection Agency (EPA) provides pesticide registration, and the states provide legal authority and oversight, the implementation is usually decentralized to the state, county, or city level. Mosquito control operations are organized, in most instances, into fully independent mosquito abatement districts, public works departments, local health departments. In some cases, municipalities engage independent private contractors to undertake mosquito control within their jurisdictions. In sub–Saharan Africa (SSA), where most vector-borne disease endemic countries lie, mosquito control is organized centrally at the national level. In this model, the disease control programmes (national malaria control programmes or national malaria elimination programmes (NMCP/NMEP)) are embedded within the central governments’ ministries of health (MoHs) and drive vector control policy development and implementation. Because of the high disease burden and limited resources, the primary endpoint of mosquito control in these settings is reduction of mosquito borne diseases, primarily, malaria. In the United States, however, the endpoint is mosquito control, therefore, significant (or even greater) emphasis is laid on nuisance mosquitoes as much as disease vectors. The authors detail experiences and learnings gathered by the delegation of African vector control professionals that participated in a formal exchange programme initiated by the Pan-African Mosquito Control Association (PAMCA), the University of Notre Dame, and members of the American Mosquito Control Association (AMCA), in the United States between the year 2021 and 2022. The authors highlight the key components of mosquito control operations in the United States and compare them to mosquito control programmes in SSA countries endemic for vector-borne diseases, deriving important lessons that could be useful for vector control in SSA.

Background The Aedes aegypti mosquito, a primary vector of arboviruses such as dengue, Zika, yellow fever, and chikungunya, poses a significant public health threat worldwide. Its adaptability and genetic diversity complicate control efforts, enabling rapid resistance evolution. Pyrethroid insecticides, a cornerstone of vector control, target voltage-gated sodium channels, yet resistance driven by knockdown resistance ( kdr ) mutations and detoxification mechanisms have undermined their efficacy. Methods This review summarizes findings from a targeted literature search, exploring the genetic and molecular mechanisms driving pyrethroid resistance worldwide, focusing on kdr mutations. Results Over twenty distinct kdr alleles were reported across global populations, including those functionally confirmed on the recombinant sodium channel such as V253F, V410L, L982W, I1011M, V1016G and F1534C. Indicators of the global impact of pyrethroid resistance include the field selection of highly resistant populations in which kdr mutation frequencies exceed 90%, deltamethrin resistance ratios as high as 249-fold, and permethrin resistance exceeding 500-fold. In laboratory-selected pyrethroid-resistant strains, resistance ratios can surpass 1,000-fold. Conclusions We provide an updated status of pyrethroid resistance in Ae. aegypti and a framework on how the results of molecular tests and toxicity bioassays can be applied to practical mosquito control programs. Control strategies must integrate multidisciplinary approaches, including Integrated Vector Management (IVM), which emphasizes targeted interventions, community engagement, and sustainable practices. Despite advances in analyzing resistance, very few studies measure frequency of genotypes, determine phenotypic resistance (resistance ratios), and assess standardized field efficacy in the same populations, including field measurements of pesticide deposited, leaving a critical implementation gap. This lack of integration creates major gaps in translating laboratory resistance diagnostics into actionable field control decisions. Empirical data on how cuticular thickening and behavioral avoidance alter post-treatment survivorship are especially sparse, limiting the predictive power of current methodologies. By assessing the current understanding of pyrethroid resistance in Ae. aegypti, this review informs the development of resilient, evidence-based interventions to mitigate the public health impact of diseases transmitted by Ae. aegypti. Graphical Abstract

Background The World Health Organization (WHO) has emphasized the urgent need for alternative strategies to chemical insecticides for controlling mosquito populations, particularly the invasive Aedes species, which are known vectors of arboviruses. Among these alternative approaches, the sterile insect technique (SIT) is experiencing rapid development, with numerous pilot trials being conducted worldwide. Main text This review aims to elucidate the principles of SIT and highlight the significant recent advancements that have facilitated its scalability. I also employ a phased conditional approach to categorize the progression of 39 projects, drawing on peer reviewed studies, press releases and direct communication with project managers. This review indicates that a substantial number of projects illustrate the efficacy of SIT in suppressing Aedes populations, with one project even demonstrating a reduction in dengue incidence. I offer several recommendations to mitigate potential failures and address the challenges of compensation and overcompensation when implementing SIT field trials. Furthermore, I examine the potential implications of male mating harassment on the effectiveness of SIT in reducing disease transmission. Conclusions This comprehensive assessment underscores the promise of SIT as a viable strategy for mosquito control. The insights gained from these trials not only contribute to the understanding of SIT’s effectiveness but also highlight the importance of careful project management and ecological considerations in the pursuit of public health objectives. Graphical Abstract

Background Malaria prevention in Africa is mainly through the use of long-lasting insecticide treated nets (LLINs). The objective of the study was to assess the effect of supplementing LLINs with either larviciding with Bacillus thuringiensis israelensis (Bti) or community education and mobilization (CEM), or with both interventions in the context of integrated vector management (IVM). Methods The study involved a factorial, cluster-randomized, controlled trial conducted in Malindi and Nyabondo sites in Kenya and Tolay site in Ethiopia, to assess the impact of the following four intervention options on mosquitoes and malaria prevalence: LLINs only (arm 1); LLINs and Bti (arm 2); LLINs and CEM (arm 3); and, LLINs combined with Bti and CEM (arm 4). Between January 2013 and December 2015, CDC light traps were used to sample adult mosquitoes during the second, third and fourth quarter of each year in 10 houses in each of 16 villages at each of the three study sites. Larvae were sampled once a fortnight from potential mosquito-breeding habitats using standard plastic dippers. Cross-sectional malaria parasite prevalence surveys were conducted involving a total of 11,846 primary school children during the 3-year period, including 4800 children in Tolay, 3000 in Malindi and 4046 in Nyabondo study sites. Results Baseline relative indoor anopheline density was 0.11, 0.05 and 0.02 mosquitoes per house per night in Malindi, Tolay and Nyabondo sites, respectively. Nyabondo had the highest recorded overall average malaria prevalence among school children at 32.4%, followed by Malindi with 5.7% and Tolay 1.7%. There was no significant reduction in adult anopheline density at each of the three sites, which could be attributed to adding of the supplementary interventions to the usage of LLINs. Malaria prevalence was significantly reduced by 50% in Tolay when using LLINs coupled with application of Bti, community education and mobilization. The two other sites did not reveal significant reduction of prevalence as a result of combining LLINs with any of the other supplementary interventions. Conclusion Combining LLINs with larviciding with Bti and CEM further reduced malaria infection in a low prevalence setting in Ethiopia, but not at sites with relatively higher prevalence in Kenya. More research is necessary at the selected sites in Kenya to periodically determine the suite of vector control interventions and broader disease management strategies, which when integrated would further reduce adult anopheline populations and malaria prevalence beyond what is achieved with LLINs.

Dengue fever remains a significant public health concern in Sri Lanka, leading to recurrent epidemics and imposing substantial socio-economic burdens. This study aimed to assess the efficacy of the Sterile Insect Technique (SIT) against Aedes albopictus (Skuse), the predominant dengue vector in the country, through a pilot field trial of an Integrated Vector Management (IVM) strategy including the SIT. The pilot trial was conducted in the Gampaha district, which reports the second-highest number of dengue cases in the country. A total of 3,300,000 sterile males, exposed to a 50 Gy radiation dose, were released over 33 weeks (100,000/week) within a 30-hectare release area. Entomological assessments were conducted at 115 trapping stations over a period of 71 weeks (October 2020–August 2022). Induced sterility of 98.16% in mosquito eggs was reached within the release area as compared to the control area (binomial generalized linear mixed model, deviance 2.408, df = 2, p  = 0.016), indicating a notable impact of the SIT. The trial achieved nearly 98% suppression of adult vector mosquitoes, with a sustained suppression effect for 13 weeks post cessation of releases. These findings suggest that SIT can be effectively integrated as a potential additional tool into the future IVM strategy in Sri Lanka. La dengue demeure un problème de santé publique majeur au Sri Lanka, entraînant des épidémies récurrentes et imposant un lourd fardeau socio-économique. Cette étude visait à évaluer l’efficacité de la technique de l’insecte stérile (TIS) contre Aedes albopictus (Skuse), le principal vecteur de la dengue dans le pays, grâce à un essai pilote sur le terrain dans le cadre d’une stratégie de gestion intégrée des vecteurs incluant la TIS. Cet essai pilote a été mené dans le district de Gampaha, qui enregistre le deuxième plus grand nombre de cas de dengue du pays. Au total, 3 300 000 mâles stériles, exposés à une dose d'irradiation de 50 Gy, ont été relâchés pendant 33 semaines (100 000/semaine) dans une zone de 30 hectares. Des suivis entomologiques ont été menés dans 115 stations de piégeage sur une période de 71 semaines (octobre 2020-août 2022). Une stérilité induite de 98,16 % des œufs de moustiques a été atteinte dans la zone de lâcher par rapport à la zone témoin (modèle mixte linéaire généralisé binomial, écart-type 2,408, ddl = 2, p  = 0,016), indiquant un impact notable de la TIS. L’essai a permis d’obtenir une suppression de près de 98 % des moustiques vecteurs adultes, avec un effet de suppression persistant pendant 13 semaines après l’arrêt des lâchers. Ces résultats suggèrent que la TIS peut être efficacement intégrée comme un outil supplémentaire potentiel dans la future stratégie de contrôle intégré des vecteurs au Sri Lanka.

Background A significant portion of malaria transmission occurs outdoors, especially in the Asia–Pacific region. Current capacity to control such outdoor biting and resting mosquitoes is inadequate, and an expanded range of tools to deploy in outdoor situations is required. This paper explores the range of options available, their current status and potential for effective implementation. Methods A literature review of the status of classes of interventions to reduce outdoor biting was conducted, including: attractive targeted sugar baits, endectocides, outdoor residual spraying, fogging, mass trapping, genetic modification techniques (3 categories), larval source management, repellents (4 categories), raised platforms, and zooprophylaxy. While not product class-specific, social engagement and behaviour change, and the more encompassing integrated vector management framework are also described as enabling strategies. The product-specific interventions were chosen if they were the subject of multiple peer-reviewed papers, and have some evidence of effectiveness. The status and potential for effective implementation are provided for each. Results There are many vector control interventions that contribute to control populations of outdoor biting mosquitoes or lead to a reduction of transmission potential. Larval Source Management is effective in some contexts but not others, and has WHO endorsement as a Supplemental Method for vector control. Spatial emanators/repellents have recently received WHO recommendation for indoor application, but may also be effective in the peridomestic space and temporary shelters. Topical repellents are effective for short-term exposure but less for long-term community protection. Endectocides offer potential in focal locations, especially as they bring benefits in helminth control for domestic animals and has good community acceptance, Gene drive holds the possibility for incisive vector control but remains a longer-term vision. Conclusion There is no universally applicable tool to prevent outdoor transmission. Each has its own utility, depending on local context. The best approach is integrating complementary techniques and community engagement to provide a broad shield of response against outdoor biting mosquitoes. As the WHO Integrated Vector Management framework recommends, it is through a broad approach of combined interventions, along with community engagement, improved data for decision-making, cross-sectoral collaboration and capacity building that can more effectively address outdoor biting of malaria vectors.

In the last 2 decades, there has been an increase in the geographic range and frequency of vector-borne diseases. Management of mosquito populations has become challenging due to increasing rates of resistance to existing insecticidal products and formulations. Several alternative tools have emerged to suppress or replace mosquito populations. One of these tools is the In2Care Mosquito Station (In2Care station). This dual-action station contains the insect growth regulator pyriproxyfen which disrupts the development of immatures and the entomopathogenic fungus Beauveria bassiana (B. bassiana) strain GHA which kills exposed adult mosquitoes. The In2Care stations have previously been shown to effectively control Aedes aegypti in field settings at a density of 6 stations/acre rather than the label-recommended 10 stations/acre. To further test the efficacy of low station density deployment, we deployed In2Care stations in the Pleasant Street Historic District of Gainesville, Florida, at a density of 3 stations/acre over a period of 2 years in the presence or absence of ground larvicidal applications.The deployment of stations resulted in no measurable impact on Ae. aegypti and Culex quinquefasciatus adult or immature abundance suggesting that the low-density deployment of In2Care stations is insufficient to reduce Ae. aegypti and Cu. quinquefasciatus abundance within treatment areas. Graphical Abstract

Culex quinquefasciatus is an important mosquito vector responsible for the transmission of filarial worms, arthropod-borne viruses like Oropouche, St. Louis encephalitis, and West Nile and protozoans that cause avian malaria. Due to insecticide resistance documented in Cx. quinquefasciatus populations worldwide, integrated vector management programs can benefit from new strategies to control this species. The In2Care Mosquito Station (In2Care station), a commercially available dissemination station containing pyriproxyfen (PPF) and Beauveria bassiana spores, has been shown to be effective against skip-ovipositing Aedes aegypti and Aedes albopictus in previously conducted semifield and field trials.To determine the potential of Cx. quinquefasciatus adult females to autodisseminate PPF and if the In2Care station could be used for Cx. quinquefasciatus control, we assessed its efficacy in a semifield setting against wild Cx. quinquefasciatus. We found that the In2Care station was attractive to gravid Cx. quinquefasciatus females, with a significantly higher percentage of egg rafts laid in the In2Care station compared to alternative ovipots. Adult females successfully autodisseminated PPF from the In2Care station to surrounding ovipots, leading to a significant increase in mosquito emergence inhibition. Additionally, adult Cx. quinquefasciatus exposure to B. bassiana spores significantly reduced mosquito survivorship. These results suggest that the In2Care station may be effective against Cx. quinquefasciatus in addition to Ae. aegypti and Ae. albopictus. Additional field evaluations are needed to assess impacts at the population level.

Background Due to outdoor and residual transmission and insecticide resistance, long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) will be insufficient as stand-alone malaria vector control interventions in many settings as programmes shift toward malaria elimination. Combining additional vector control interventions as part of an integrated strategy would potentially overcome these challenges. Larval source management (LSM) and structural house improvements (HI) are appealing as additional components of an integrated vector management plan because of their long histories of use, evidence on effectiveness in appropriate settings, and unique modes of action compared to LLINs and IRS. Implementation of LSM and HI through a community-based approach could provide a path for rolling-out these interventions sustainably and on a large scale. Methods/design We will implement community-based LSM and HI, as additional interventions to the current national malaria control strategies, using a randomised block, 2 × 2 factorial, cluster-randomised design in rural, southern Malawi. These interventions will be continued for two years. The trial catchment area covers about 25,000 people living in 65 villages. Community participation is encouraged by training community volunteers as health animators, and supporting the organisation of village-level committees in collaboration with The Hunger Project, a non-governmental organisation. Household-level cross-sectional surveys, including parasitological and entomological sampling, will be conducted on a rolling, 2-monthly schedule to measure outcomes over two years (2016 to 2018). Coverage of LSM and HI will also be assessed throughout the trial area. Discussion Combining LSM and/or HI together with the interventions currently implemented by the Malawi National Malaria Control Programme is anticipated to reduce malaria transmission below the level reached by current interventions alone. Implementation of LSM and HI through a community-based approach provides an opportunity for optimum adaptation to the local ecological and social setting, and enhances the potential for sustainability. Trial Registration Registered with The Pan African Clinical Trials Registry on 3 March 2016, trial number PACTR201604001501493.