Japanese Encephalitis Virus Surveillance in U.S. Army Installations in the Republic of Korea from 2021 to 2023.

Japanese encephalitis is a disease caused by the Japanese encephalitis virus (JEV) and is a concern for U.S. military personnel stationed in the Republic of Korea (ROK). The recent literature reports a potential shift from GI to GV as the dominant genotype circulating in east Asia. In the ROK, GV has been reported in a few Culex spp., but not in the main JEV vector, Cx. tritaeniorhynchus. The goal of this surveillance was to shed light on the current knowledge of the epidemiology of JEV in the ROK by analyzing mosquito collection data from three consecutive years, 2021-2023, and molecularly detecting and genotyping JEV in all Culex spp. collected in several military locations across the ROK. In this study, we detected only JEV GI in Cx. tritaeniorhynchus in 2021 samples. In contrast, all 2022 and 2023 positive samples were GV and detected in Cx. bitaeniorhynchus, Cx. orientalis, and Cx. pipiens. Results support a shift in JEV genotype in the ROK and suggest that for GV, Culex spp. other than Cx. tritaeniorhynchus may be playing an important role.

Tiny silver bullets: silver nanoparticles are insecticidal to Culicoides sonorensis (Diptera: Ceratopogonidae) biting midge larvae.

Insecticide formulations with safer environmental profiles and limited off-target effects are desirable to manage medical and veterinary pests. Silver nanoparticles are insecticidal against mosquitos, nonbiting midges, and other insects. The biting midge, Culicoides sonorensis Wirth and Jones, is a vector of agriculturally important pathogens in much of the United States, and this study aimed to examine the insecticidal properties of silver nanoparticles in larvae of this species. Mortality of third-instar larvae was assessed daily for 7 days after exposure to concentrations of silver nanoparticles, sorghum polymer particles, and hybrid silver-sorghum polymer particles. Both silver nanoparticles and silver-sorghum polymer particles were insecticidal, but sorghum polymer particles alone did not significantly contribute to larval mortality. Concentrations of 100 mg/liter of silver nanoparticles achieved >50% mortality at day 7, and 200 mg/liter treatments achieved >75% larval mortality within 24 h. The antimicrobial properties of silver nanoparticles were also examined, and culturable bacteria were recovered from larval-rearing media at 200 mg/liter but not at 400 mg/liter of silver nanoparticles. These data suggest that C. sonorensis larval mortality is primarily caused by silver nanoparticle toxicity and not by the reduction of bacteria (i.e., a larval food source). This work describes the first use of silver nanoparticles in C. sonorensis and shows the potential insecticide applications of these nanoparticles against this agricultural pest. The grain-polymer particles also successfully carried insecticidal silver nanoparticles, and their utility in loading diverse compounds could be a novel toxin delivery system for biting midges and similar pests.

Modeling the 2014-2015 Vesicular Stomatitis Outbreak in the United States Using an SEIR-SEI Approach.

Vesicular stomatitis (VS) is a vector-borne livestock disease caused by the vesicular stomatitis New Jersey virus (VSNJV). This study presents the first application of an SEIR-SEI compartmental model to analyze VSNJV transmission dynamics. Focusing on the 2014-2015 outbreak in the United States, the model integrates vertebrate hosts and insect vector demographics while accounting for heterogeneous competency within the populations and observation bias in documented disease cases. Key epidemiological parameters were estimated using Bayesian inference and Markov chain Monte Carlo (MCMC) methods, including the force of infection, effective reproduction number (Rt), and incubation periods. The model revealed significant underreporting, with only 10-24% of infections documented, 23% of which presented with clinical symptoms. These findings underscore the importance of including competence and imperfect detection in disease models to depict outbreak dynamics and inform effective control strategies accurately. As a baseline model, this SEIR-SEI implementation is intended to serve as a foundation for future refinements and expansions to improve our understanding of VS dynamics. Enhanced surveillance and targeted interventions are recommended to manage future VS outbreaks.

MINIstock: Model for INsect Inclusion in sustainable agriculture: USDA-ARS's research approach to advancing insect meal development and inclusion in animal diets.

Animal agriculture is under pressure to increase efficiency, sustainability, and innovation to meet the demands of a rising global population while decreasing adverse environmental effects. Feed cost and availability are 2 of the biggest hurdles to sustainable production. Current diets depend on sources of grain and animal byproduct protein for essential amino acids which have limited sustainability. Insects have arisen as an attractive, sustainable alternative protein source for animal diets due to their favorable nutrient composition, low space and water requirements, and natural role in animal diets. Additionally, insects are capable of bioremediating waste streams including agricultural and food waste, manure, and plastics helping to increase their sustainability. The insect rearing industry has grown rapidly in recent years and shows great economic potential. However, state-of-the-art research is urgently needed to overcome barriers to adoption in commercial animal diets such as regulatory restrictions, production scale issues, and food safety concerns. To address this need, the USDA Agricultural Research Service "MINIstoc: Model for INsect Inclusion" project was created to bring together diverse scientists from across the world to synergistically advance insect meal production and inclusion in animal diets. Here, we provide a short review of insects as feed while describing the MINIstock project which serves as the inspiration for the Journal of Economic Entomology Special Collection "Insects as feed: sustainable solutions for food waste and animal production practices."

Conceptualization, design, and construction of a novel insect mass trapping device: the USDA Biomass Harvest Trap (USDA-BHT).

The use of insects as animal feed has the potential to be a green revolution for animal agriculture as insects are a rich source of high-quality protein. Insect farming must overcome challenges such as product affordability and scalability before it can be widely incorporated as animal feed. An alternative is to harvest insect pests from the environment using mass trapping devices and use them as animal feed. For example, intensive agricultural environments generate large quantities of pestiferous insects and with the right harvest technologies, these insects can be used as a protein supplement in traditional animal daily rations. Most insect trapping devices are limited by the biomass they can collect. In that context, and with the goal of using wild collected insects as animal feed, the United States Department of Agriculture-Biomass Harvest Trap (USDA-BHT) was designed and built. The USDA-BHT is a valuable mass trapping device developed to efficiently attract, harvest, and store flying insects from naturally abundant agricultural settings. The trap offers a modular design with adjustable capabilities, and it is an inexpensive device that can easily be built with commonly available parts and tools. The USDA-BHT is also user-friendly and has customizable attractants to target various pest species.

Harvesting insect pests for animal feed: potential to capture an unexploited resource.

The demand for animal protein grows as the human population increases. Technological and genetic advances in traditional animal agriculture will not produce enough protein to meet future needs without significant innovations such as the use of insects as protein sources. Insect farming is growing insects, whereas insect harvesting is collecting insects from their natural habitats to produce high-quality protein for animal feed or human food. Intensive agricultural environments produce tremendous quantities of pestiferous insects and with the right harvest technologies these insects can be used as a protein supplement in traditional animal daily rations. An avenue to exploit these insects is to use traps such as the United States Department of Agriculture-Biomass Harvest Trap (USDA-BHT) to efficiently attract, harvest, and store insects from naturally abundant agricultural settings. The modular design allows for a low cost, easy to build and fix device that is user friendly and has customizable attractants to target various pest species. Although insect harvesting faces substantial challenges, including insect biomass quantity, seasonal abundance and preservation, food safety, and economic and nutritional evaluation, the potential for utilizing these pests for protein shows tremendous promise. In this forum, insect harvesting is discussed, including its potential, limitations, challenges, and research needs. In addition, the use of a mass trapping device is discussed as a tool to increase the biomass of insects collected from the environment.

Assessment of the USDA Biomass Harvest Trap (USDA-BHT) device as an insect harvest and mosquito surveillance tool.

Insects are a promising source of high-quality protein, and the insect farming industry will lead to higher sustainability when it overcomes scaling up, cost effectiveness, and automation. In contrast to insect farming (raising and breeding insects as livestock), wild insect harvesting (collecting agricultural insect pests), may constitute a simple sustainable animal protein supplementation strategy. For wild harvest to be successful sufficient insect biomass needs to be collected while simultaneously avoiding the collection of nontarget insects. We assessed the performance of the USDA Biomass Harvest Trap (USDA-BHT) device to collect flying insect biomass and as a mosquito surveillance tool. The USDA-BHT device was compared to other suction traps commonly used for mosquito surveillance (Centers for Disease Control and Prevention (CDC) light traps, Encephalitis virus surveillance traps, and Biogents Sentinel traps). The insect biomass harvested in the USDA-BHT was statistically higher than the one harvested in the other traps, however the mosquito collections between traps were not statistically significantly different. The USDA-BHT collected some beneficial insects, although it was observed that their collection was minimized at night. These findings coupled with the fact that sorting time to separate the mosquitoes from the other collected insects was significantly longer for the USDA-BHT, indicate that the use of this device for insect biomass collection conflicts with its use as an efficient mosquito surveillance tool. Nevertheless, the device efficiently collected insect biomass, and thus can be used to generate an alternative protein source for animal feed.

Assessing dengue risk globally using non-Markovian models.

Dengue is a vector-borne disease transmitted by Aedes mosquitoes. The worldwide spread of these mosquitoes and the increasing disease burden have emphasized the need for a spatio-temporal risk map capable of assessing dengue outbreak conditions and quantifying the outbreak risk. Given that the life cycle of Aedes mosquitoes is strongly influenced by habitat temperature, numerous studies have utilized temperature-dependent development rates of these mosquitoes to construct virus transmission and outbreak risk models. In this study, we contribute to existing research by developing a mechanistic model for the mosquito life cycle that accurately captures its non-Markovian nature. Beginning with integral equations to track the mosquito population across different life cycle stages, we demonstrate how to derive the corresponding differential equations using phase-type distributions. This approach can be further applied to similar non-Markovian processes that are currently described with less accurate Markovian models. By fitting the model to data on human dengue cases, we estimate several model parameters, allowing the development of a global spatiotemporal dengue risk map. This risk model employs temperature and precipitation data to assess the environmental suitability for dengue outbreaks in a given area.

Mosquitoes harvested from rice fields as alternative protein ingredient in broiler feed: insights from the first pilot study.

Global population continuous growth and increasing consumers' demands for protein-rich diets have posed sustainability challenges for traditional livestock feed sources. Consequently, exploring alternative and sustainable protein sources has become imperative to address the environmental burden and resource limitations associated with conventional ingredients. With respect to food security assurance, insects have emerged as a promising solution due to their exceptional nutritional profile, rapid reproduction rates, and low environmental impact. In the present pilot study, 10% of a soybean meal-based diet was replaced by adult mosquitoes harvested from rice fields. The objective was to assess the effect of this partial substitution on meat quality aspects and consumer acceptance. A total of 40 Cobb hybrid broiler chickens were randomly placed in a control and a mosquito-fed group. The study was conducted for 42 days and carcass physicochemical, nutritional, and microbiological characteristics, as well as sensory attributes were evaluated. Overall, results regarding quality attributes were comparable between the control and the treatment group. The organoleptic evaluation showed that the thighs from the mosquito-fed group had the highest overall consumer acceptance. These outcomes indicate that mosquitoes could be successfully used as a protein source for broiler feed without compromising the quality and acceptability of the meat.

Variable gut pH as a potential mechanism of tolerance to Bacillus thuringiensis subsp. israelensis toxins in the biting midge Culicoides sonorensis.

BACKGROUND: Toxins of Bacillus thuringiensis subsp. israelensis (Bti) are safer alternatives for controlling dipteran pests such as black flies and mosquitoes. The biting midge Culicoides sonorensis (Diptera: Ceratopogonidae) is an important pest of livestock in much of the United States and larval midges utilize semi-aquatic habitats which are permissive for Bti product application. Reports suggest that Bti products are ineffective at killing biting midges despite their taxonomic relation to black flies and mosquitoes. Here, we investigate the toxicity of a Bti-based commercial insecticide and its active ingredient in larval Culicoides sonorensis. A suspected mechanism of Bti tolerance is an acidic larval gut, and we used a pH indicator dye to examine larval Culicoides sonorensis gut pH after exposure to Bti. RESULTS: The lethal concentration to kill 90% (LC90) of larvae of the commercial product (386 mg/L) was determined to be almost 10 000 times more than that of some mosquito species, and no concentration of active ingredient tested achieved 50% larval mortality. The larval gut was found to be more acidic after exposure to Bti which inhibits Bti toxin activity. By comparison, 100% mortality was achieved in larval Aedes aegypti at the product's label rate for this species and mosquito larvae had alkaline guts regardless of treatment. Altering the larval rearing water to alkaline conditions enhanced Bti efficacy when using the active ingredient. CONCLUSION: We conclude that Bti is not practical for larval Culicoides sonorensis control at the same rates as mosquitos but show that alterations or additives to the environment could make the products more effective. © 2024 Society of Chemical Industry.

Evaluating Temperature Effects on Bluetongue Virus Serotype 10 and 17 Coinfection in Culicoides sonorensis.

Bluetongue virus (BTV) is a segmented, double-stranded RNA virus transmitted by Culicoides midges that infects ruminants. As global temperatures increase and geographical ranges of midges expand, there is increased potential for BTV outbreaks from incursions of novel serotypes into endemic regions. However, an understanding of the effect of temperature on reassortment is lacking. The objectives of this study were to compare how temperature affected Culicoides survival, virogenesis, and reassortment in Culicoides sonorensis coinfected with two BTV serotypes. Midges were fed blood meals containing BTV-10, BTV-17, or BTV serotype 10 and 17 and maintained at 20 °C, 25 °C, or 30 °C. Midge survival was assessed, and pools of midges were collected every other day to evaluate virogenesis of BTV via qRT-PCR. Additional pools of coinfected midges were collected for BTV plaque isolation. The genotypes of plaques were determined using next-generation sequencing. Warmer temperatures impacted traits related to vector competence in offsetting ways: BTV replicated faster in midges at warmer temperatures, but midges did not survive as long. Overall, plaques with BTV-17 genotype dominated, but BTV-10 was detected in some plaques, suggesting parental strain fitness may play a role in reassortment outcomes. Temperature adds an important dimension to host-pathogen interactions with implications for transmission and evolution.

Assessing the feasibility, safety, and nutritional quality of using wild-caught pest flies in animal feed.

Studies have investigated the potential of using farmed insects in animal feeds; however, little research has been done using wild-caught insects for this purpose. Concerns about inadequate quantities collected, environmental impacts, and the spread of pathogens contribute to the preferred utilization of farmed insects. Nevertheless, by harvesting certain pest species from intensified agricultural operations, producers could provide their animals with affordable and sustainable protein sources while also reducing pest populations. This study explores the possibility of collecting large quantities of pest flies from livestock operations and analyzes the flies' nutritional content, potential pathogen load, and various disinfection methods. Using a newly designed mass collection-trapping device, we collected 5 kg of biomass over 13 wk, primarily house flies, from a poultry facility. While a substantial number of pests were removed from the environment, there was no reduction in the fly population. Short-read sequencing was used to compare the bacterial communities carried by flies from differing source populations, and the bacterial species present in the fly samples varied based on farm type and collection time. Drying and milling the wild-caught flies as well as applying an additional heat treatment significantly reduced the number of culturable bacteria present in or on the flies, though their pathogenicity remains unknown. Importantly, these disinfection methods did not affect the nutritional value of the processed flies. Further research is necessary to fully assess the safety and viability of integrating wild-caught insects into livestock feed; however, these data show promising results in favor of such a system.

Outlook on RNAi-Based Strategies for Controlling Culicoides Biting Midges.

Culicoides are small biting midges with the capacity to transmit important livestock pathogens around much of the world, and their impacts on animal welfare are likely to expand. Hemorrhagic diseases resulting from Culicoides-vectored viruses, for example, can lead to millions of dollars in economic damages for producers. Chemical insecticides can reduce Culicoides abundance but may not suppress population numbers enough to prevent pathogen transmission. These insecticides can also cause negative effects on non-target organisms and ecosystems. RNA interference (RNAi) is a cellular regulatory mechanism that degrades mRNA and suppresses gene expression. Studies have examined the utility of this mechanism for insect pest control, and with it, have described the hurdles towards producing, optimizing, and applying these RNAi-based products. These methods hold promise for being highly specific and environmentally benign when compared to chemical insecticides and are more transient than engineering transgenic insects. Given the lack of available control options for Culicoides, RNAi-based products could be an option to treat large areas with minimal environmental impact. In this study, we describe the state of current Culicoides control methods, successes and hurdles towards using RNAi for pest control, and the necessary research required to bring an RNAi-based control method to fruition for Culicoides midges.

Culicoides-borne Orbivirus epidemiology in a changing climate.

Orbiviruses are of significant importance to the health of wildlife and domestic animals worldwide; the major orbiviruses transmitted by multiple biting midge (Culicoides) species include bluetongue virus, epizootic hemorrhagic disease virus, and African horse sickness virus. The viruses, insect vectors, and hosts are anticipated to be impacted by global climate change, altering established Orbivirus epidemiology. Changes in global climate have the potential to alter the vector competence and extrinsic incubation period of certain biting midge species, affect local and long-distance dispersal dynamics, lead to range expansion in the geographic distribution of vector species, and increase transmission period duration (earlier spring onset and later fall transmission). If transmission intensity is associated with weather anomalies such as droughts and wind speeds, there may be changes in the number of outbreaks and periods between outbreaks for some regions. Warmer temperatures and changing climates may impact the viral genome by facilitating reassortment and through the emergence of novel viral mutations. As the climate changes, Orbivirus epidemiology will be inextricably altered as has been seen with recent outbreaks of bluetongue, epizootic hemorrhagic disease, and African horse sickness outside of endemic areas, and requires interdisciplinary teams and approaches to assess and mitigate future outbreak threats.

The increasing threat of Rift Valley fever virus globalization: strategic guidance for protection and preparation.

Rift Valley fever virus (RVFV) (Bunyavirales: Phlebovirus) is a prominent vector-borne zoonotic disease threat to global agriculture and public health. Risks of introduction into nonendemic regions are tied to changing climate regimes and other dynamic environmental factors that are becoming more prevalent, as well as virus evolutionary factors and human/animal movement. Endemic to the African continent, RVFV has caused large epizootics at the decadal scale since the early 20th century but has spread to the Arabian Peninsula and shows increasing patterns of interepizootic transmission on the annual scale. This virus can be transmitted by mosquitoes as well as through direct contact with infected tissues and can cause sporadic to widespread morbidity and mortality in domestic ungulate livestock as well as humans. High viremias in infected livestock moved for legal and illegal trade as well as in infected mosquitoes or human travelers can spread this virus worldwide. With increasing global commerce, it is likely RVFV will be introduced to new areas with suitable hosts, mosquito vector species, and environments. However, the strong mosquito component of RVFV epidemiology combined with advancements in vaccines, diagnostics, and virus evolutionary factors create opportunities for strategies to leverage models of connectivity among potential source and emerging regions to target surveillance and mitigation activities to reduce the risk of RVFV introduction, or contain the virus should it be introduced, into new regions.

Fatal Food: Silver-Coated Grain Particles Display Larvicidal Activity in Culex quinquefasciatus.

Mosquitoes pose a significant risk to millions of people worldwide since they can transmit pathogens. Current methods to control mosquito populations include the use of synthetic pesticides. Nanotechnology may be a solution to develop new mosquito control. However, one barrier to expanding the impact of nanomaterials is the ability to mass-produce the particles. Here, we report a novel hybrid particle synthesis combining micro- and nanoparticles using the coprecipitation technique with the potential for mass production. These particles may have applications as a mosquito larvacide. The particles reported here were designed using a microparticle zein polymer as the core and a nanoparticle silver as the active ingredient. The hybrid NPs reported here targeted a late-stage mosquito larvae and that resulted in a high larval mortality concentration (1.0 ppm, LC90) and suppression of pupal emergence at 0.1 ppm. This research demonstrates the efficacy of a plant-based core with a metal-based AI coating (AgNPs) against larval mosquitoes.

Immigration and seasonal bottlenecks: high inbreeding despite high genetic diversity in an oscillating population of Culicoides sonorensis (Diptera: Ceratopogonidae).

Most population genetic studies concern spatial genetic differentiation, but far fewer aim at analyzing the temporal genetic changes that occur within populations. Vector species, including mosquitoes and biting midges, are often characterized by oscillating adult population densities, which may affect their dispersal, selection, and genetic diversity over time. Here, we used a population of Culicoides sonorensis from a single site in California to investigate short-term (intra-annual) and long-term (inter-annual) temporal variation in genetic diversity over a 3 yr period. This biting midge species is the primary vector of several viruses affecting both wildlife and livestock, thus a better understanding of the population dynamics of this species can help inform epidemiological studies. We found no significant genetic differentiation between months or years, and no correlation between adult populations and the inbreeding coefficient (FIS). However, we show that repeated periods of low adult abundance during cooler winter months resulted in recurring bottleneck events. Interestingly, we also found a high number of private and rare alleles, which suggests both a large, stable population, as well as a constant influx of migrants from nearby populations. Overall, we showed that the high number of migrants maintains a high level of genetic diversity by introducing new alleles, while this increased diversity is counterbalanced by recurrent bottleneck events potentially purging unfit alleles each year. These results highlight the temporal influences on population structure and genetic diversity in C. sonorensis and provide insight into factors effecting genetic variation that may occur in other vector species with fluctuating populations.

PICTUREE-Aedes: A Web Application for Dengue Data Visualization and Case Prediction.

Dengue fever remains a significant public health concern in many tropical and subtropical countries, and there is still a need for a system that can effectively combine global risk assessment with timely incidence forecasting. This research describes an integrated application called PICTUREE-Aedes, which can collect and analyze dengue-related data, display simulation results, and forecast outbreak incidence. PICTUREE-Aedes automatically updates global temperature and precipitation data and contains historical records of dengue incidence (1960-2012) and Aedes mosquito occurrences (1960-2014) in its database. The application utilizes a mosquito population model to estimate mosquito abundance, dengue reproduction number, and dengue risk. To predict future dengue outbreak incidence, PICTUREE-Aedes applies various forecasting techniques, including the ensemble Kalman filter, recurrent neural network, particle filter, and super ensemble forecast, which are all based on user-entered case data. The PICTUREE-Aedes' risk estimation identifies favorable conditions for potential dengue outbreaks, and its forecasting accuracy is validated by available outbreak data from Cambodia.

Evaluation of an open forecasting challenge to assess skill of West Nile virus neuroinvasive disease prediction.

BACKGROUND: West Nile virus (WNV) is the leading cause of mosquito-borne illness in the continental USA. WNV occurrence has high spatiotemporal variation, and current approaches to targeted control of the virus are limited, making forecasting a public health priority. However, little research has been done to compare strengths and weaknesses of WNV disease forecasting approaches on the national scale. We used forecasts submitted to the 2020 WNV Forecasting Challenge, an open challenge organized by the Centers for Disease Control and Prevention, to assess the status of WNV neuroinvasive disease (WNND) prediction and identify avenues for improvement. METHODS: We performed a multi-model comparative assessment of probabilistic forecasts submitted by 15 teams for annual WNND cases in US counties for 2020 and assessed forecast accuracy, calibration, and discriminatory power. In the evaluation, we included forecasts produced by comparison models of varying complexity as benchmarks of forecast performance. We also used regression analysis to identify modeling approaches and contextual factors that were associated with forecast skill. RESULTS: Simple models based on historical WNND cases generally scored better than more complex models and combined higher discriminatory power with better calibration of uncertainty. Forecast skill improved across updated forecast submissions submitted during the 2020 season. Among models using additional data, inclusion of climate or human demographic data was associated with higher skill, while inclusion of mosquito or land use data was associated with lower skill. We also identified population size, extreme minimum winter temperature, and interannual variation in WNND cases as county-level characteristics associated with variation in forecast skill. CONCLUSIONS: Historical WNND cases were strong predictors of future cases with minimal increase in skill achieved by models that included other factors. Although opportunities might exist to specifically improve predictions for areas with large populations and low or high winter temperatures, areas with high case-count variability are intrinsically more difficult to predict. Also, the prediction of outbreaks, which are outliers relative to typical case numbers, remains difficult. Further improvements to prediction could be obtained with improved calibration of forecast uncertainty and access to real-time data streams (e.g. current weather and preliminary human cases).

Are You Still Using 6-Volt Batteries for Your Insect Traps?

The most prevalent insect sampling and surveillance problem is powering insect traps in the field. Most modern light traps use 6-V power supplies such as the Centers for Disease Control and Prevention (CDC) suction trap. Buck converter modules efficiently reduce 12-V direct current power to 6-V, which permits the use of higher voltage batteries with lower voltage traps, resulting in longer operational duration and reduced labor requirements associated with replacing and recharging batteries in the field. We evaluated several battery configurations of 6- and 12-V lead-acid batteries in various sizes (10-20 ampere-hours) and addressed, in the circuit design, common problems that occur when using the buck converter (such as crossing polarity and excessive battery depletion). The efficacy of each configuration was assessed by measuring the voltage and suction while powering a 6-V CDC light trap. The buck converter permitted the use of cheaper and more commonly available 12-V batteries to run the CDC light traps and resulted in longer effective operation time as measured by air speed.