During 2020 to 2021 and 2023 to 2025, inspections of more than 1,300 unique storm sewer basins across an approximately 270 sq mi (699.3 sq km) area of Cook County were inspected. During inspections Culex pipiens and Cx. restuans made up 79.0% and 20.8%, respectively, of 11,999 larvae collected during inspections within epidemiological weeks 22 to 43, or June through October. Culex pipiens was the dominant species in basins when average weekly West Nile virus (WNV) percent positive pools were the highest, generally through the months of July through September. This finding suggests that, at a minimum, levels of larvicide control remain near or at 100% mortality in basins during this time of both high Cx. pipiens and high WNV. Ensuring closer to maximum in control in basins during times when Cx. pipiens can be found in basins may also minimize potential for larvicide resistance of that species as sublethal doses would be less common.
The mosquito species Aedes bertrami was collected during an expedition conducted during summer 2017, in a site of a conserved area of the Calakmul Biosphere Reserve, Campeche State, southeastern Mexico. Within this material, a single adult female was first identified as species of Ae. (Protomacleaya). At the time, taxonomically challenging specimens were classified only to genus or subgenus level. The collection was recently reexamined as part of curatorial activities concerning mosquito specimens collected from the Yucatan Peninsula and held at UAAAN-UL. The single adult female previously identified as Ae. (Protomacleaya) sp. was reidentified as Ae. bertrami based on morphological characters. This is the first record of Ae. bertrami in Mexico, and the first record outer from Belize, where the species has only been recorded. With the addition of Ae. bertrami to the mosquito fauna in Mexico, there are 255 species currently recorded in the country, with 25 species in the subgenus Protomacleaya of Aedes, and 12 species in the Terrens Group.
Mechanical aspirators are useful tools for capturing mosquitoes and collecting a greater diversity of species and physiological states than do attractive traps. Here we describe a novel aspirator design for collecting resting mosquitoes in diverse habitats. The aspirator is constructed of readily available components and is powered by a rechargeable 12-V battery.
Nonnative and invasive mosquito species threaten public and veterinary health in the southern USA by introducing pathogens into new regions, making early detection of these species essential. To address this need, the Mosquito Biodiversity Enhancement and Control of Non-native Species (Mosquito BEACONS) Working Group provided training to mosquito surveillance professionals between 2021 and 2024. More than 190 individuals from public health, pest control, and research sectors participated. A 12-question online survey evaluated participant engagement, awareness, and application of skills learned. Twenty-two participants completed the survey, and results indicated that the training led to measurable behavioral changes, with participants applying the learned skills when returning to their home institutions. This study represents the first evaluation of an integrated pest management (IPM) training program focused on invasive species and offers a framework for improving future IPM training evaluations.
Between September 2024 to January 2026, 100 professionals working with mosquito and/or tick vectors and located primarily in the upper Midwest of the United States were interviewed. These interviews were used to assess the work performed in the region and to highlight successes and challenges of the work. The results suggest that collaboration within and across agencies is a strength, whereas a major challenge is that the public and politicians do not understand or appreciate the importance of their work in vector surveillance, vector control, and public outreach.
Lee County Mosquito Control District (LCMCD) implemented helicopter-mounted Light Detection and Ranging (LiDAR) technology to create high-resolution elevation models for refining larval mosquito habitat treatment boundaries in coastal and inland environments. Using a Ranger ULTRA laser scanning system equipped with an IMU-30 inertial measurement unit mounted on an Airbus H125 helicopter, the district mapped approximately 184,567 ha across Lee County during the 2026 dry season (January 13 to May 1), achieving vertical accuracy of 2.0 cm and horizontal point densities exceeding 30 points per square m. The LiDAR-derived elevation data enabled precise delineation of tidal and rainfall-driven flooding zones that may reduce treatment areas and associated larvicide costs while maintaining operational effectiveness. This operational note describes the equipment specifications, flight parameters, data processing methodology, cost-benefit outcomes, and lessons learned from large-scale implementation of LiDAR for integrated mosquito management and represents the first large-scale operational implementation of LiDAR within a mosquito control program.
Mosquito surveillance is essential for monitoring disease risk. However, the high cost of industry-standard traps often limits sampling density in resource-constrained settings. This study evaluated a modified Katchy Indoor Insect Trap, a low-cost ultraviolet-light-emitting diode suction trap, for outdoor field surveillance in Florida. A randomized Latin square design was used to compare the modified Katchy to the New Standard Centers for Disease Control and Prevention (CDC) Miniature Light Trap and the CDC Miniature Downdraft Blacklight Trap across three habitat types over 18 nights in 2024. A total of 4,213 mosquitoes were collected from all three traps. All traps exhibited similar mosquito abundance during the spring and summer months. However, during summer, the modified Katchy trap captured a greater species richness (18 species) than either CDC trap models (10 species each). Trap performance varied across species, and community similarity among trap types shifted seasonally. At approximately $60, including modifications, the Katchy trap represents a cost-effective option that performs comparably to the CDC models tested in this study. Although further multisite longitudinal studies are necessary to assess its performance across diverse ecological settings, these findings suggest that the modified Katchy trap is a promising supplemental surveillance tool for programs seeking to increase trap density under budget constraints.
Mosquito pool surveillance is a cornerstone of arbovirus risk assessment, yet traditional metrics such as the minimum infection rate (MIR) can understate infection probability and, as conventionally reported, do not provide uncertainty quantification that properly accounts for pooling. We analyzed 7 yr (2018-2024) of mosquito pool surveillance data using pooled maximum likelihood estimation (MLE) with transformed Clopper-Pearson confidence intervals to estimate per-mosquito infection probabilities. The dataset comprised 4,930 pools (246,500 mosquitoes) collected across 80 surveillance sites and tested for 6 arbovirus assay targets covering eastern equine encephalitis, St. Louis encephalitis, West Nile, chikungunya, dengue, and Zika viruses. Viral circulation was sparse (5 positive pools, 0.10% overall positivity), but the pooled-likelihood framework still produced interpretable infection-probability estimates together with conservative upper confidence bounds in zero-positive and sparse-positive weeks. Peak infection probabilities ranged from 0.678 per 1,000 mosquitoes for West Nile virus in August 2022 to 2.667 per 1,000 for chikungunya and Zika virus detections in October 2018. In this low-positivity setting, MIR, pooled MLE, and the Firth/Burrows bias-reduced estimator were numerically close in the observed positive weeks, whereas the main practical gain came from interval estimates that made sampling uncertainty explicit. These results support moving from MIR-only summaries to a broader pooling-aware reporting framework in mosquito surveillance. Reporting both per-mosquito infection estimates and interval bounds places sparse detections and zero-positive weeks on a common operational scale and supports interpretation alongside other surveillance indicators.
ABSTRACT:Anopheles pseudopunctipennis is one of the most important malaria vectors in the Americas and historically contributed to transmission in northwestern Argentina. Although Argentina was certified malaria-free in 2019, surveillance of vector populations remains relevant to prevent reintroduction. We used ecological niche models to identify climatically suitable areas for An. pseudopunctipennis in Argentina, using occurrence records and bioclimatic variables from WorldClim 2.1. Records were compiled from the literature, biodiversity databases, and personal collections, and were filtered to remove duplicates, records lacking reliable coordinates, and records with high geographic uncertainty. To reduce the effect of clustered sampling on model calibration, occurrences were spatially thinned at 5 km. Models were calibrated with MaxEnt in the northwestern accessible area of the species in Argentina, testing combinations of feature classes and regularization multipliers. Candidate models were evaluated using omission rate, validation Area Under the Curve, and Akaike Information Criterion with Correction. After filtering, 312 records from 287 localities were retained. The best-supported model used LQHP features with regularization multiplier 1.0 and showed an average 10% omission rate of 0.11, validation AUC of 0.83, and the lowest AICc among candidate models (ΔAICc = 0). Suitable conditions were concentrated mainly in northwestern Argentina, especially in Jujuy, Salta, Tucumán, and Catamarca, with additional suitable areas in parts of Santiago del Estero, San Juan, San Luis, Córdoba, Formosa, and Chaco. These results provide a first approximation of climatically suitable areas for An. pseudopunctipennis in Argentina and may support vector surveillance in a country where malaria has been eliminated but remains at risk of reintroduction.
Anthropogenic activities cause changes in natural environments, affecting the ecology of Anopheles mosquitoes and, therefore, increasing the potential for malaria transmission. Immature Anopheles were collected from different larval habitats in 3 geographical localities of northwestern Argentina: El Oculto, where the wild habitat included a mountain river; Aguas Blancas, where the peri-rural habitat consisted of stream ravines; and San Ramón de la Nueva Orán, where the peri-urban habitat comprised puddles, ponds, and irrigation and drainage channels. The incidence rate of each anopheline species was calculated according to the larval habitat. Additionally, to analyze the effect of environmental variables, the mean of each variable in each larval habitat was determined and related to the incidence of each anopheline species through Pearson's correlation coefficient. A total of 5,553 larvae belonging to the genus Anopheles were collected. The most abundant species was Anopheles pseudopunctipennis (33.35%), followed by An. (Nyssorhynchus) argyritarsis (28.47%), An. (Nys.) evansae (16.64%), and An. (Nys.) strodei (14.62%). Both An. pseudopunctipennis and An. argyritarsis were present across all larval habitats. Considering the larval habitats separately, An. argyritarsis emerged as the most abundant species in both the mountain river (wild habitat) and stream ravines (peri-rural habitat), while An. evansae and An. strodei predominated in the irrigation and drainage channels (peri-urban habitat). In the peri-rural habitat, mean water temperature was positively associated with the presence of An. argyritarsis. In the peri-urban habitat, mean temperature was positively associated with An. strodei and An. evansae, while a strong negative relationship between these 2 species and water pH was also observed. This study showed the importance of longitudinal entomological surveillance, not only in wild and peri-rural environments due to the abundance of main malaria vectors, An. pseudopunctipennis and An. argyritarsis, but also in peri-urban areas. Considering that both vector species can transition to urban sites, as observed in other countries, current and future changes in these habitats require further studies. Consequently, research should focus on the emergence of new larval habitats that could favor a higher abundance of these malaria vector species.
The continued efficacy of adulticide products is critical for effective mosquito control and rapid response during arboviral disease outbreaks. In Collier County, Florida, documented pyrethroid resistance in Aedes aegypti has increased reliance on other chemistries, including products containing the organophosphate naled. To evaluate current susceptibility status to naled, 7 Ae. aegypti populations were collected from "hot spot" locations in Collier County between 2022 and 2026 and assessed using the Centers for Disease Control and Protection Bottle Bioassay. Five populations, including all residential and commercial sites, were classified as susceptible. One population collected from a tire shop demonstrated developing resistance in both 2022 (93.75%) and 2023 (92.49%), while a golf course population exhibited confirmed resistance in 2022 (52.23%) but shifted to developing resistance in 2023 (90.43%) following site redevelopment. Although most populations remain susceptible, the detection of localized reduced susceptibility highlights the dynamic nature of resistance and the importance of continued comprehensive monitoring. These findings suggest that naled should be used with caution against Ae. aegypti, particularly during arbovirus outbreaks where rapid and reliable vector suppression is essential, and support the need for proactive resistance management and insecticide rotation strategies to preserve operational efficacy.
Mosquito oviposition site selection is governed by chemical, physical, microbial, conspecific, and heterospecific cues, which can alter water composition and breeding site quality, yet field-based evaluations of how specific water chemistry parameters influence egg-laying behavior remain limited. Improving the sensitivity of oviposition-based surveillance tools, such as ovitraps, requires identifying chemical cues that reliably attract or deter gravid females under field conditions. We assessed oviposition responses of wild mosquito populations, including Aedes aegypti and Ae. albopictus, to 4 water treatments (geosmin-beetroot peel extract [hereafter geosmin extract], pH, salinity, and sucrose) across a gradient of concentrations at 4 field sites in Indian River County, FL, from September to December 2025. Egg counts were collected weekly from paired ovitraps and analyzed using negative binomial generalized linear mixed models with Dunnett's post-hoc contrasts and oviposition activity indices (OAI). Geosmin extract at the highest dose (3.75 ml) significantly increased oviposition by 123% relative to controls (P < 0.001), making it the only stimulant identified. Salinity produced a strong dose-dependent deterrent effect, with complete oviposition cessation at 3% (OAI = -0.56, P = 0.003). Sucrose showed a consistent deterrent trend, with evidence of significant reduction at the highest concentration. pH modifications showed variable but generally deterrent effects, with pH 9.0 reducing egg counts by 55%. These findings demonstrate that geosmin extract is a promising field-deployable stimulant for improving ovitrap sensitivity in surveillance programs, whereas salinity and sucrose function as effective oviposition deterrents. Notably, this study provides the first field evidence that a crude aqueous extract prepared from red beet (Beta vulgaris) peels, a natural source of geosmin, stimulates oviposition by gravid Ae. albopictus, extending previous work conducted exclusively on Ae. aegypti.
We provide an updated checklist of the mosquito species that occur in Maine. Seven species are added as new state records: Anopheles crucians, Aedes grossbecki, Ae. rempeli, Ae. thibaulti, Culex erraticus, Culiseta inornata, and Psorophora ciliata.
Culicoides biting midges are a major nuisance in coastal residential areas of Australia, yet effective control strategies remain limited. This study evaluated the effectiveness of a residual insecticide treatment applied to a purpose-grown vegetation barrier in reducing biting midge nuisance in adjacent coastal residences, with secondary effects on mosquito abundance also monitored. Biting midge and mosquito populations were monitored continuously using automated smart traps (BG-Counter®) over 18 wk, including 11 wk of pretreatment and 7 wk posttreatment surveillance. During the pretreatment surveillance period, properties adjacent to the vegetation barrier (n = 4) recorded 71% fewer biting midges than nonadjacent properties (n = 2), although this effect was temporally variable (95% confidence interval [CI]: -95% to +55%) and not significant. No reduction in mosquito abundance was observed during the same period. Following treatment of the barrier with a residual insecticide (BiFlex AquaMax®, bifenthrin 100 g/liter), biting midge and mosquito populations declined by 86% (95% CI: 77-92%) and 79% (95% CI: 68-86%), respectively, across the study landscape, including in areas with and without the vegetation barrier. A significant barrier-insecticide interaction for both groups indicated that reductions were greatest in residences adjacent to the vegetation barrier. Decreases in mosquito abundance following application of the residual spray suggests that the vegetation barrier functioned as important harborage habitat, enabling targeted control within and beyond its immediate boundary. These findings support the integration of insecticide-treated vegetation barriers into pest management programs targeting nuisance biting midge and mosquito populations in coastal residential environments.
Mitigating the arboviral threat in Jamaica is predominantly dependent on vector control efforts which target the Aedes aegypti mosquito. This, however, is being hampered because of increased insecticide resistance to synthetic chemicals. Currently, environmentally friendly botanical agents are gaining interest globally as they possess promising mosquitocidal properties. In this study, the larvicidal activity of essential oils extracted from the leaves of Jamaican Hyptis verticillata and Pimenta dioica were evaluated at 24 h against Ae. aegypti, utilizing a modified World Health Organization bioassay. Subsequent gas chromatography-mass spectrometry analysis of the extracts revealed that the most abundant compounds of H. verticillata and P. dioica were cadina-4,10(15)-dien-3-one and eugenol, respectively. A dose-dependent response was noted, and LC50 values of 16.06 ppm and 56.23 ppm were obtained for H. verticillata and P. dioica respectively, against the Rockefeller laboratory strain of Ae. aegypti. Evaluation of H. verticillata against field strains showed that increased pigmentation was among the main phenotypical changes observed post treatment. The calculated resistance ratios varied across sites, with RR50 values ranging from 0.727 in Duhaney Park to 1.578 in Savanna La Mar, indicating overall low resistance across all strains. The current findings support the potential use of essential oils as alternative larvicidal agents in Jamaica.
The Metropolitan Mosquito Control District, based in St. Paul, MN, has been protecting the residents of the Twin Cities metropolitan area of Minnesota from disease and annoyance from mosquitoes and other pests since 1958. Regarding mosquitoes, this mission is carried out by administering a wide-sweeping control program that is almost entirely larvicidal. For control of the Culex species, residual products containing the active ingredient S-methoprene have been heavily used for decades without product rotation in stormwater catch basins and ditches. In the fall of 2025, a preliminary investigation of S-methoprene and pyriproxyfen resistance was conducted using standardized laboratory bioassays. The preliminary data indicate that a field-collected population of Culex pipiens has developed high resistance to S-methoprene, with a resistance ratio at 50% mortality (RR50) value of 56.29 and were tolerant to pyriproxyfen with an RR50 of 4.35. Field-collected Cx. restuans remain susceptible to S-methoprene with an RR50 of 1.79. The preliminary data laid the groundwork needed to warrant further testing to determine where else this resistance is occurring and to what extent.
The Texas Panhandle (26 counties) and High Plains regions (41 counties) have one of the highest West Nile virus (WNV) and St. Louis encephalitis virus (SLEV) human neuro-incidence rates in the USA, yet surveillance for these pathogens is predominately performed through passive measures (e.g., detecting human cases at hospitals and other health clinics). There is an overall lack of active pathogen surveillance (e.g., mosquito surveillance) systems in these regions, leading to knowledge gaps in our understanding of arboviral dynamics in enzootic cycles. To address this limitation, we implemented 2 surveillance projects in 2024: localized surveillance of WNV and SLEV in the city of Lubbock, TX, and regional surveillance throughout the Panhandle and High Plains regions of the state. We used BG sentinel traps and Centers for Disease Control and Prevention light traps baited with dry ice to collect Culex mosquitoes in a multitude of habitats for both projects. All mosquitoes were identified using a dichotomous key, and then female Cx. tarsalis and Cx. quinquefasciatus were tested for WNV and SLEV as super-pools (e.g., samples containing supernatant from up to 7 individual pools that contained between 1 and 50 mosquitoes) using a combination of commercial RNA extraction kits and real-time quantitative polymerase chain reaction. In the Lubbock study, we collected 21,066 Cx. tarsalis and 15,918 Cx. quinquefasciatus, which were tested as 308 and 238 super-pools, respectively. Sixty-three Cx. tarsalis and 36 Cx. quinquefasciatus super-pools tested positive for WNV, and 8 Cx. tarsalis and 4 Cx. quinquefasciatus super-pools tested positive for SLEV. Sixteen Panhandle counties were sampled by DSHS, which collected 1,060 Cx. tarsalis and 56 Cx. quinquefasciatus. A total of 23 super-pools of Cx. tarsalis and Cx. quinquefasciatus were tested, of which only 3 (13%) Cx. tarsalis samples were found to be positive for WNV. Overall we found an abundant number of Culex spp. mosquitoes that tested positive for both viruses, which supports the Texas Panhandle and High Plains regions as high-risk regions for WNV in the United States.
Reliable determination of mosquito age and reproductive status is critical for understanding disease transmission dynamics and evaluating vector control strategies. In this study, we investigated the use of mid-infrared (MIR) spectroscopy combined with multivariate statistical models to predict the gonotrophic state (parity) and chronological age of Aedes triseriatus. Using a reflectance sampling geometry, we acquired IR spectra from the hind tibiae of Ae. triseriatus females to assess gonotrophic status. Spectral data in the 1800-650 cm-1 range were normalized and subjected to second-derivative transformation to minimize baseline variation. Partial least squares discriminant analysis (PLS-DA) was used to classify mosquitoes as parous or nulliparous based on their IR spectra, achieving clear separation between groups in the validation set. The model demonstrated 97% (95% CI: 92%-99%) classification accuracy, with a positive predictive value of 97% (95% CI: 88%-100%) and a negative predictive value of 97% (95% CI: 91%-99%), indicating robust statistical differentiation based on gonotrophic status. Using female Ae. triseriatus aged from 2 to 35 days old we assessed the ability of MIR to predict age. Partial least squares regression (PLS-R) yielded a strong correlation (R = 0.96) between spectral data and mosquito age. Statistical testing (ANOVA, Tukey's HSD) revealed that the model could not reliably distinguish between mosquitoes aged 2 and 7 days but could reliably distinguish Ae. triseriatus ≤ 7 days (1 week) old from those 2-5 weeks of age at the 95% confidence level. Collectively, these findings demonstrate that MIR spectroscopy, coupled with chemometric modeling (PLS analyses), provides a rapid and reproducible method for determining reproductive status and age in Ae. triseriatus. The methods reported here may improve La Crosse virus transmission risk assessments and better refine our understanding of enzootic maintenance and human spillover.
Ongoing surveillance of tick populations is critical for informing the health of humans, livestock, and companion animals. From 2004 to 2019 in the USA and its territories, the National Notifiable Disease Surveillance System data show a 2.1-fold increase in all reportable notifiable tick-borne diseases (TBDs) in humans. Eight tick-borne zoonotic pathogens and 1 syndrome were described for the first time in the USA between 2004 and 2024. In Missouri, 33 counties were surveyed over a 2-year period (2019 and 2021). More than 3,811 ticks were collected during the study: 89.0% Amblyomma americanum, 10.9% Dermacentor variabilis, <0.1% Amblyomma maculatum, <0.1% Haemaphysalis longicornus, and <0.1% Ixodes spp. Significantly greater tick density was found in metropolitan areas as compared to rural counties (P = 0.012). Of the 2 level I ecoregions in Missouri, the Eastern Temperate Forest (ETF) had a significantly greater tick density (P = 0.0045). Even so, D. variabilis had significantly higher density in the Great Plains ecoregion than in ETF (P = 0.031). Ozark Highlands had the highest tick density of the 5 level III ecoregions surveyed (5.12 ticks/100 m2). A moderate, positive correlation between a county's density of A. americanum nymphs and its quadrennial tick-borne disease rate was observed (r = 0.68, P = 0.002). Our study adds new data on established and reported tick populations for 13 counties and examines the relationships of tick density to TBDs and to area designation.
Dengue cases have emerged, reemerged, and surged in the Americas, Africa, Asia, and Europe. The World Health Organization reported more than 80 countries affected by dengue in 2023, with over 6.5 million infections and 7,300 deaths, surpassing prior years. Dengue virus presents extremely high risk of infections to humans in locations where cities are overcrowded and harbor large numbers of container-inhabiting Aedes species. In 2023, both Nepal and Bangladesh suffered unprecedented and extremely high case numbers of more than 51,000 and more than 321,000, respectively. In response, a regional workshop, Advancing the Efficacy of Dengue Prevention and Control, was held in April 2024 in Kathmandu, Nepal, to bring together key stakeholders and experts from Nepal, Bangladesh, and the USA to discuss novel and sustainable dengue management strategies, including how to best engage communities in dengue control. The objective of the workshop was to create a knowledge repository to build capacities at multiple levels within and between nations, to share and compare tools, look for patterns of success, eliminate redundancy, and create a touchpoint for future discussions and interventions to reduce the burden of dengue in the region.
