Mosquito Vector Control Research Articles

Indoor Residual Spraying With Fludora Fusion for Malaria Control in Pyrethroid‐Resistant Areas of Gujarat, India: A Community‐Randomized Trial

Background: The development of insecticide resistance in malaria vectors has necessitated a need to evaluate new insecticide molecules with different modes of action. In the present study, Fludora Fusion 562.5 WP‐SB (clothianidin 50% + deltamethrin 6.25% AI/kg) was evaluated for its efficacy and residual action for the control of pyrethroid‐resistant malaria vector, Anopheles culicifacies (Diptera: Culicidae), during May 2017 to February 2018 in Gujarat state, India.Methods: Fludora Fusion at the dose of 225 mg AI/m2 and bendiocarb at a dose of 400 mg AI/m2 as a positive control were sprayed in 5 villages each in districts of Kheda, Vadodara, and Panchmahal. The persistence of their efficacy on different local surfaces was determined against An. culicifacies. Entomological indices such as indoor resting density, human landing collections, pyrethrum spray collections, and exit trap collections were monitored to assess the impact of spraying.Results: The observed residual action of Fludora Fusion on mud and cement surfaces was for 6 months and bendiocarb for 3–4 months on both surfaces. Indoor resting densities and parous rate of An. culicifacies were significantly lower in houses sprayed with Fludora Fusion compared to bendiocarb‐sprayed houses. Daily entomological inoculation rate (EIR) declined from 1.275 during prespray period to 0.5225 in the Fludora Fusion arm and 0.3802 in the Ficam arm in postspray period, indicating a reduction in the malaria transmission potential of An. culicifacies in both arms.Conclusion: Based on the residual action of the Fludora Fusion on most common sprayed surfaces and its effects on the elements of vectorial capacity, Fludora Fusion at 225 mg/m2 dose was found effective for more than 6 months and could be a potential option for the control of resistant mosquito vectors.

Chromobacterium biopesticide overcomes insecticide resistance in malaria vector mosquitoes.

Vector mosquito control is an integral part of malaria control. The global emergence of insecticide resistance in malaria-transmitting Anophelines has become an impediment and has created an urgent need for novel mosquito control approaches. Here, we show that a biopesticide derived from the soil-dwelling bacterium Chromobacterium sp. Panama (Csp_P) kills insecticide-resistant Anopheles mosquitoes, regardless of their resistance mechanisms. In addition, sublethal dose of Csp_P acts as a synergist to now used chemical insecticides across multiple classes. Moreover, Csp_P reduces host-seeking behavior and malaria parasite infection in vector mosquitoes in ways that further decrease transmission. Mosquito glutathione S-transferases are essential for Csp_P's mosquito-killing mechanism. Enclosed field trials in Burkina Faso, conducted in diverse ecological settings and supported by a mathematical model, have now demonstrated its potential for malaria control in settings with widespread insecticide resistance.

Advanced vision transformers and open-set learning for robust mosquito classification: A novel approach to entomological studies.

Mosquito-related diseases pose a significant threat to global public health, necessitating efficient and accurate mosquito classification for effective surveillance and control. This work presents an innovative approach to mosquito classification by leveraging state-of-the-art vision transformers and open-set learning techniques. A novel framework has been introduced that integrates Transformer-based deep learning models with comprehensive data augmentation and preprocessing methods, enabling robust and precise identification of ten mosquito species. The Swin Transformer model achieves the best performance for traditional closed-set learning with 99.60% accuracy and 0.996 F1 score. The lightweight MobileViT technique attains an almost equivalent accuracy of 98.90% with significantly reduced parameters and model complexities. Next, the applied deep learning models' adaptability and generalizability in a static environment have been enhanced by using new classes of data samples during the inference stage that have not been included in the training set. The proposed framework's ability to handle unseen classes like insects similar to mosquitoes, even humans, through open-set learning further enhances its practical applicability employing the OpenMax technique and Weibull distribution. The traditional CNN model, Xception, outperforms the latest transformer with higher accuracy and F1 score for open-set learning. The study's findings highlight the transformative potential of advanced deep-learning architectures in entomology, providing a strong groundwork for future research and development in mosquito surveillance and vector control. The implications of this work extend beyond mosquito classification, offering valuable insights for broader ecological and environmental monitoring applications.

Application of essential oils with potential larvicides in the control of mosquito vectors of the genus Culex sp.: review

Application of essential oils with potential larvicides in the control of mosquito vectors of the genus Culex sp.: review

The Physiological Effect Of Zinc Oxide (ZnO) Nanopesticide On Aedes aegypti Larvae

Aedes aegypti is responsible for transmitting various mosquito-borne diseases. Recently, there have been concerns about the negative impacts of the insecticides used in vector control including insecticide resistance development in the mosquito population. These circumstances lead to efforts to develop other strategies for controlling mosquito vectors. As technology in nanoparticles advances, zinc oxide (ZnO) nanoparticles have the potential as the alternative for chemical pesticides for mosquito larvicides due to their optical properties and widespread usage in different industries. The purpose of this study was to determine the toxicity of ZnO nanoparticles towards Ae. aegypti larvae and to examine the physiologies of Ae. aegypti mosquito larvae treated with ZnO nanoparticles at LC50 level. Toxicity bioassays were carried out to determine LC50 and LC90 values. The larvae surface and midgut treated with LC50 ZnO were examined using the Scanning Electron Microscope (FESEM) and Dispersive X-ray spectroscopy (EDX). The LC50 and LC90 concentrations of ZnO nanoparticles after 4 hr of direct UV exposure against Ae. aegypti larvae were 49.141 mg/L and 64.195 mg/L, respectively. After exposure to ZnO nanoparticles, Ae. aegypti larvae showed morphological abnormalities, including distorted and shrunk body parts as well as midgut rupture. Overall, the findings suggest that ZnO nanoparticles have the potential to replace chemical pesticides as a means of reducing the populations of Ae. aegypti mosquitoes.

Eco-friendly synthesis of silver nanoparticles using Phyllanthus niruri leaf extract: Assessment of antimicrobial activity, effectiveness on tropical neglected mosquito vector control, and biocompatibility using a fibroblast cell line model

Abstract Mosquitoes are rapidly advancing as vectors of several severe diseases. The increasing resistance of mosquitoes and the environmental harm caused by insecticides pose significant challenges for eradicating mosquito vectors. In this study, 18 plant extracts were tested for larvicidal properties against Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi larvae. Phyllanthus niruri (Pn) showed enhanced larvicidal activity in both laboratory and field trials. The biosynthesis of silver nanoparticles (AgNPs) using Pn leaf methanol extract (Pn-LME) was confirmed by UV-visible spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and Fourier-transform infrared spectroscopy. Among various concentrations, 3 mM AgNPs exhibited significant LC90 values of 0.83, 1.46, and 9.11 ppm compared to 9.25, 93.48, and 14.60 ppm of Pn-LME against A. stephensi, C. quinquefasciatus, and A. aegypti, respectively. This indicates the high mortality of mosquito vectors at low AgNP concentrations. Additionally, Pn-AgNPs showed enhanced antibacterial activity and no cytotoxicity in normal fibroblast cells (L929). Field trials demonstrated a 98.70% decrease in mosquito larval density at A. stephensi breeding sites, a 96.55% reduction at C. quinquefasciatus sites, and a 97.85% reduction at Ae. aegypti sites. This study presents an eco-friendly and cost-effective AgNP bio-pesticide synthesized from Pn leaves for controlling and preventing the transmission of filarial, dengue, and malaria vectors.

Mosquito taste responses to human and floral cues guide biting and feeding.

The taste system controls many insect behaviours, yet little is known about how tastants are encoded in mosquitoes or how they regulate critical behaviours. Here we examine how taste stimuli are encoded by Aedes albopictus mosquitoes-a highly invasive disease vector-and how these cues influence biting, feeding and egg laying. We find that neurons of the labellum, the major taste organ of the head, differentially encode a wide variety of human and other cues. We identify three functional classes of taste sensilla with an expansive coding capacity. In addition to excitatory responses, we identify prevalent inhibitory responses, which are predictive of biting behaviour. Certain bitter compounds suppress physiological and behavioural responses to sugar, suggesting their use as potent stop signals against appetitive cues. Complex cues, including human sweat, nectar and egg-laying site water, elicit distinct response profiles from the neuronal repertoire. We identify key tastants on human skin and in sweat that synergistically promote biting behaviours. Transcriptomic profiling identifies taste receptors that could be targeted to disrupt behaviours. Our study sheds light on key features of the taste system that suggest new ways of manipulating chemosensory function and controlling mosquito vectors.

Empowering Communities through Citizen Science: Dengue Prevention in Córdoba.

Traditional mosquito vector control methods have proved ineffective in controlling the spread of dengue fever. This study aimed to assess the effectiveness of community engagement through student-led science in promoting dengue prevention and socioecological factors in the temperate urban city of Córdoba, Argentina. It assesses community perceptions, knowledge, attitudes, and preventive practices regarding dengue fever and its vector. Results showed a significant increase in knowledge about the vector and the disease and respondents' adoption of good preventive practices. Student-led science was identified as a valuable tool for reaching households and leading to behavior changes at home. Furthermore, the findings highlighted the need for school programs to address vector biology and vector-borne disease prevention all year round. This study provides invaluable insights into the effectiveness of community engagement through student-led science to promote dengue prevention and socioecological factors. The findings suggest that this approach could be used to control the spread in other regions affected by the disease.

Pemberdayaan Masyarakat dalam Penerapan PHBS untuk Pengendalian Jentik Nyamuk Aedes Aegypti di Kelurahan Sungai Pangeran

Dengue Hemorrhagic Fever (DHF) is a contagious disease caused by the Aedes aegypti mosquito, commonly found in Indonesia, particularly in areas with poor environmental sanitation. The implementation of Clean and Healthy Living Behavior (PHBS) is one of the effective strategies for controlling mosquito vectors and preventing DHF. This community service activity aims to improve public understanding and participation in the application of PHBS in Sungai Pangeran Village, Palembang, through counseling, training of Larvae Monitoring Officers (Jumantik), and community clean-up activities with the 3M Plus Movement (Draining, Closing, Burying, and additional measures). The results showed a significant increase in public knowledge about PHBS and active participation in mosquito larvae monitoring. The training of Jumantik created cadres capable of performing independent monitoring, and the community clean-up activities reduced potential mosquito breeding sites by 60%. Monitoring also showed a 35% decrease in DHF cases after the program. This activity has proven effective in raising public awareness and reducing vector-borne disease risks in the local environment. However, continued monitoring and support from local governments are needed to sustain the program.

Larvicidal Activity of Melissa officinalis and Rosmarinus officinalis Extracts and Their Lethal Impact on Detoxifying Enzymes in Aedes aegypti L. Larvae

Background & Objectives: Mosquito-borne diseases significantly impact global health, particularly in tropical regions. While synthetic insecticides are currently employed to control mosquito vectors, their detrimental effects on ecosystems and persistence necessitate alternative control methods. Botanicals, owing to their diverse phytocompounds, offer potential for controlling and preventing vector-borne diseases by targeting insect eggs and larvae. This study aimed to evaluate the toxicity of Melissa officinalis and Rosmarinus officinalis extracts (methanolic and aqueous) against Aedes aegypti larvae, a vector of arboviruses. Materials & Methods: Total protein content in control and plant extract-exposed larval homogenates was estimated using bovine serum albumin as a standard. Acetylcholinesterase (AChE) and carboxylesterase assays were performed to determine larvicidal effects. Larval mortality was assessed after 24 hours of exposure. Results: Our findings revealed that the methanolic leaf extract of M. officinalis exhibited superior larvicidal activity (100% at 1000 ppm) compared to the methanolic R. officinalis extract (84±2.45% at 1000 ppm). In contrast, the aqueous extracts of both plant species inferred no larvicidal activity. The LC50 and LC90 values for M. officinalis methanolic extract were 378.7 ppm and 795.8 ppm, respectively, whereas those for R. officinalis were 648.9 ppm and 1152.9 ppm, respectively. Furthermore, biochemical assays measuring total protein, acetylcholinesterase, α-carboxylesterase, and β-carboxylesterase activities were conducted for M. officinalis, corroborating and substantiating its larvicidal properties. Conclusion: This study demonstrates that the methanolic leaf extract of M. officinalis possesses significant larvicidal efficacy against A. aegypti. These findings suggest that this plant or its phytocompounds could serve as a bioinsecticide, offering a potential alternative to environmentally toxic and non-biodegradable synthetic insecticides.

A Review of the Latest Control Strategies for Mosquito-Borne Diseases.

Mosquito-borne diseases are persistent and potentially severe posing a threat to global pandemic preparedness. The risk of mosquito-borne virus transmission is rapidly increasing due to the unprecedented spread of viruses such as dengue and chikungunya, the disruption of global mosquito-borne disease control efforts following the emergence of coronavirus diseases 2019 (COVID-19) in 2019, global warming, and human activities. To address this global challenge, various innovative mosquito control technologies are being developed worldwide. This paper summarizes the latest advances in mosquito vector control, focusing on China's latest mosquito control strategies, to provide insights into implementing novel mosquito-borne disease control measures.

Role of Non-Residential Larval Habitats in Aedes Spatiotemporal Egg Production.

Aedes mosquitoes play a pivotal role as vectors of several arboviral diseases, presenting significant public health challenges worldwide. Their invasive success in tropical regions has raised substantial medical concerns. In Guatemala, Aedes mosquitoes are widely distributed and are the primary vectors of the dengue virus. Efforts to control and monitor Aedes populations have evolved over time, incorporating strategies such as spatial repellents, larvicides, genetic modifications, and targeted interventions. Previous research has shown the heterogeneous spatial-temporal distribution of these mosquitoes within each season, influenced by temperature variations and favorable environmental conditions for breeding. This study analyzed hot-spot patterns of spatiotemporal egg density in Santa Elena de la Cruz, Petén, Guatemala, from March to September 2022. The aim was to determine whether these patterns were influenced by non-residential larval habitats with plant cover that are not treated by healthcare entities, as well as the proximity between such habitats. Our findings include the collection and registration of over 16,000 Aedes eggs during the study period. Local analyses revealed hot-spot patterns in egg densities associated with non-residential larval habitats and their proximity. These insights highlight critical focal points where targeted interventions could be implemented more effectively, resulting in cost-efficient mosquito vector control.

Discarded vehicle tires and their association with mosquito vector abundance across socioenvironmental gradients in New Orleans, LA.

Discarded vehicle tires serve as habitat for mosquito vectors. In New Orleans, Louisiana, discarded tires are an increasingly important public concern, especially considering that the city is home to many medically important mosquito species. Discarded tires are known to be associated with mosquito abundance, but how their presence interacts with other socioenvironmental gradients to influence mosquito ecology is poorly understood. Here, we ask whether discarded tire distribution could be explained by social factors, particularly median income, home vacancy and human population density, and whether these factors interact with urban heat islands (UHI) to drive mosquito vector assemblages. We surveyed tire piles across the city and adult mosquitoes in 12 sites, between May and October of 2020. We compared this data with the social indicators selected and UHI estimates. Our results show that median income and human population density were inversely related to tire abundance. Tire abundance was positively associated with Aedes albopictus abundance in places of low heat (LS) severity. Heat was the only predictor for the other monitored species, where high heat corresponded to higher abundance of Aedes aegypti, and LS to higher abundance of Culex quinquefasciatus. Our results suggest that low-income, sparsely populated neighborhoods of New Orleans may be hotspots for discarded vehicle tires, and are associated with higher abundances of at least one medically important mosquito (Ae. albopictus). These findings suggest potential locations for prioritizing source reduction efforts to control mosquito vectors and highlight discarded tires as a potential exposure pathway to unequal disease risk for low-income residents.

Molecular identification and GC-MS analysis of a newly isolated novel bacterium (Lysinibacillus sp. VCRC B655) for mosquito control.

Mosquitoes are widespread globally and have contributed to transmitting pathogens to humans and the burden of vector-borne diseases. They are effectively controlled at their larval stages by biocontrol agents. Unravelling natural sources for microbial agents can lead us to novel potential candidates for managing mosquito-borne diseases. In the present study, an attempt was made to isolate a novel bacterium from the field-collected agricultural soil for larvicidal activity and promising bacterial metabolites for human healthcare. Field-collected soil samples from the Union territory of Puducherry, India, have been used as the source of bacteria. Isolate VCRC B655 belonging to the genus Lysinibacillus was identified by 16S rRNA gene sequencing and exhibited promising larvicidal activity against different mosquito species, including Culex (Cx.) quinquefasciatus, Anopheles (An.) stephensi, and Aedes (Ae.) aegypti. The lethal concentration (LC) of Lysinibacillus sp. VCRCB655 was observed to be high for Cx. quiquefasciatus: LC50 at 0.047mg/l, LC90 at 0.086mg/l, followed by An. stephensi and Ae. aegypti (LC50: 0.6952mg/l and 0.795mg/l) respectively. Additionally, metabolic profiling of the culture supernatant was carried out through Gas chromatography and Mass spectrophotometry (GC/MS) and identified 15 major secondary metabolites of different metabolic classes. Diketopiperazine (DKPs), notably pyro lo [1, 2-a] pyrazine1, 4-dione, are the abundant compounds reported for antioxidant activity, and an insecticide compound benzeneacetic acid was also identified. A new bacterial isolate, Lysinibacillus sp. VCRC B655 has been identified with significant larvicidal activity against mosquito larvae with no observed in non-target organisms. GC-MS analysis revealed diverse bioactive compounds with substantial biological applications. In conclusion, Lysinibacillus sp. VCRC B655 showed promise as an alternative biocontrol agent for mosquito vector control, with additional biological applications further enhancing its significance.

Pembentukan Kader Juru Pemantau Jentik (JUMANTIK) pada Kader Kesehatan di Wilayah Kerja Puskesmas Pagar Agung Kecamatan Lahat, Indonesia Tahun 2023

Dengue hemorrhagic fever, or DHF, is a common disease affecting many countries worldwide, particularly in Southeast Asia and the Western Pacific. It is estimated that there are 100–400 million infections annually. Although there is no specific treatment for this virus, controlling mosquito vectors remains the primary focus in controlling its spread. The formation of mosquito surveillance cadres is a crucial strategy in reducing DHF cases by monitoring breeding sites of Aedes aegypti mosquitoes. Training for these cadres and clean village activities are vital for enhancing public knowledge and awareness of DHF prevention. These activities demonstrate that education and training increase the knowledge and participation of mosquito surveillance cadres. Therefore, the formation of mosquito surveillance cadres and practical training are critical steps in the efforts to prevent and control DHF.

Design and evaluation of an efficient mosquito trap.

Vector mosquito control is important for preventing and controlling mosquito-borne infectious diseases. This study designed and developed a mosquito killer (MK) with a specific light wavelength, simulated human body temperature, human odor, and a photocatalyst to stimulate CO2 based on the physiological characteristics and ecological habits of mosquitoes. We tested the trapping effect of individual and multiple mosquito-trapping elements of the MK through two-way selection experiments and compared them with several commercial mosquito traps. The 365 nm wavelength MK was significantly more effective than the 395 nm (Cx. quinquefasciatus: 62.00% vs. 34.25%; Ae. albopictus: 50.75% vs 45.00%, An. sinensis: 49.75% vs 39.00%). Mosquitoes captured by the MK with heaters at 365 nm were significantly more than those captured by the MK without heaters at 365 nm. A trap with a 365 nm wavelength, heating element, and lure showed significantly better capture effectiveness than MK with a 365 nm wavelength, heating element, but without lure (Cx. quinquefasciatus: 67.00% vs. 29.75%, Ae. albopictus: 60.25% vs 36.25%, An. sinensis: 49.75% vs 39.75%). The coated photocatalyst trap with a 365 nm wavelength, heating element, and lure showed significantly better capture effectiveness than the trap without coating (Cx. quinquefasciatus: 54.25% vs. 42.50%; Ae. albopictus: 53.50% vs 44.00%, An. sinensis: 50.00% vs 41.25%). This trap demonstrated a significantly better capture advantage for Cx. quinquefasciatus and Ae. albopictus compared to the three commercial products. The developed mosquito trap with multiple attractant factors significantly enhanced the capture effectiveness of common mosquitoes. © 2024 Society of Chemical Industry.

Midgut morphology of the predator mosquito Lutzia bigoti (Diptera: Culicidae) and its implications for feeding behavior

Lutzia mosquitoes (Theobald, 1903) are predaceous during their larval stages, but the adult feeding is not clearly understood, especially in relation to blood feeding. In case these mosquitoes are harmless to humans and related animals, they can be useful in biological control of mosquito vectors of pathogens. Investigating the midgut morphology is a good strategy to understand the feeding behavior of this species. The midgut in Lutzia bigoti Bellardi, 1862 displays two distinct portions, a thin anterior midgut and a more dilated posterior midgut. Digestive cells form a single epithelium in the midgut. These cells have long and packed microvilli at their apex and membrane infoldings at their basal portion, the basal labyrinth. The epithelium is supported by a basal lamina. Regarding their cytoplasm, it is noteworthy the abundance of mitochondria, distributed in an apical-basal fashion, and also a whirl-shaped endoplasmic reticulum in the posterior midgut. Basal cells are also found in the midgut of L. bigoti, resembling regenerative cells. The general organization of L. bigoti's midgut closely resembles that of numerous hematophagous mosquitoes previously documented. However, it diverges due to the presence of a peritrophic matrix even when exclusively fed on sugary solutions. Peculiar aspects of L. bigoti’s midgut are discussed and compared to those of other mosquito species.

Assessment of biorational larvicides and botanical oils against Culex quinquefasciatus Say (Diptera: Culicidae) larvae in laboratory conditions

Mosquitoes are known vectors that transmit deadly diseases to millions of people across the globe. The reliance on synthetic insecticides has been the sole way to combat mosquito vectors for decades. In recent years, the extensive use of conventional insecticides in mosquito suppression has led to significant pesticide resistance and serious human health hazards. In this light, investigating the potential application of biorational compounds for vector management has drawn significant attention. We, hereby, evaluated the efficacy of three microbial derivative biorational insecticides, abamectin, spinosad, and buprofezin, and two botanical oils, neem (Azadirachta indica A. Juss) and karanja oil (Pongamia pinnata Linn.) against the Culex quinquefasciatus under laboratory conditions. The fourth-instar C. quinquefasciatus larvae were exposed to different concentrations of the selected larvicides and lethality was estimated based on LC50 and LT50 with Probit analysis. All larvicides showed concentration-dependent significant effects on survival and demonstrated larvicidal activity against C. quinquefasciatus larvae. However, abamectin exerted the highest toxicity (LC50 = 10.36 ppm), exhibited statistically significant effects on C. quinquefasciatus larval mortality, followed by spinosad (LC50 = 21.32 ppm) and buprofezin (LC50 = 56.34 ppm). Abamectin caused larval mortality ranged from 30.00 to 53.33 % and 53.00–70.00 % at 06 and 07 h after treatment (HAT), respectively. In the case of botanicals, karanja oil (LC50 = 216.61 ppm) was more lethal (more than 1.5 times) and had a shorter lethal time than neem oil (LC50 = 330.93 ppm) and showed a classic pattern of relationship between concentrations and mortality over time. Overall, the present study highlighted the potential of deploying new generation biorational pesticides and botanicals in mosquito vector control programs.

A DNA barcode reference library of Croatian mosquitoes (Diptera: Culicidae): implications for identification and delimitation of species, with notes on the distribution of potential vector species

BackgroundMosquitoes pose a risk to human health worldwide, and correct species identification and detection of cryptic species are the most important keys for surveillance and control of mosquito vectors. In addition to traditional identification based on morphology, DNA barcoding has recently been widely used as a complementary tool for reliable identification of mosquito species. The main objective of this study was to create a reference DNA barcode library for the Croatian mosquito fauna, which should contribute to more accurate and faster identification of species, including cryptic species, and recognition of relevant vector species.MethodsSampling was carried out in three biogeographical regions of Croatia over six years (2017–2022). The mosquitoes were morphologically identified; molecular identification was based on the standard barcoding region of the mitochondrial COI gene and the nuclear ITS2 region, the latter to identify species within the Anopheles maculipennis complex. The BIN-RESL algorithm assigned the COI sequences to the corresponding BINs (Barcode Index Number clusters) in BOLD, i.e. to putative MOTUs (Molecular Operational Taxonomic Units). The bPTP and ASAP species delimitation methods were applied to the genus datasets in order to verify/confirm the assignment of specimens to specific MOTUs.ResultsA total of 405 mosquito specimens belonging to six genera and 30 morphospecies were collected and processed. Species delimitation methods assigned the samples to 31 (BIN-RESL), 30 (bPTP) and 28 (ASAP) MOTUs, with most delimited MOTUs matching the morphological identification. Some species of the genera Culex, Aedes and Anopheles were assigned to the same MOTUs, especially species that are difficult to distinguish morphologically and/or represent species complexes. In total, COI barcode sequences for 34 mosquito species and ITS2 sequences for three species of the genus Anopheles were added to the mosquito sequence database for Croatia, including one individual from the Intrudens Group, which represents a new record for the Croatian mosquito fauna.ConclusionWe present the results of the first comprehensive study combining morphological and molecular identification of most mosquito species present in Croatia, including several invasive and vector species. With the exception of some closely related species, this study confirmed that DNA barcoding based on COI provides a reliable basis for the identification of mosquito species in Croatia.Graphical

A New Aqueous Formulation from Indigenously Isolated Bacillus <i>Thuringiensis Israelensis</i> VCRC B646 for Mosquito Control

In the present study, in order to control mosquito vectors in the field, a new aqueous formulation was developed using an indigenously isolated bacterial strain of Bacillus thuringiensis israelensis VCRC B646. The composition of formulation was, Bti lyophilized powder (5%), sodium benzoate (0.15%), sodium alginate (2.5%), Congo red (0.03%), citric acid (0.15%), glycerol (6%), molasses (8%) and polyethylene glycol (3%) in 100ml of water. Laboratory bioassay was carried out using this formulation against the late third instar of mosquito larvae. The result showed that the LC50 and LC90 values against Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi were 0.0082 and 0.016 mg/ l, 0.0084 and 0.0172 mg/ l, 0.0139 and 0.0294 mg/ l, respectively. Results from simulated field trial showed that the efficacy of Bti formulation at LC90 level was highly significant up to six weeks (42 days). Thereafter, the formulation efficacy was started declining. No side effect was observed against non-target aquatic organisms. It was concluded from this study that the formulation developed from newly isolated strain if B. thuringiensis israelensis VCRC B646 was very useful on the control of mosquito vectors.