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Aedes aegypti is an important mosquito vector of human disease with a wide distribution across the globe. Climatic conditions and ecological pressure drive differences in the biology of several populations of this mosquito species, including blood‐feeding behaviour and vector competence. However, no study has compared activity and/or sleep among different populations/lineages of Ae. aegypti. Having recently established sleep‐like states in three mosquito species with observable differences in timing and amount of sleep among species, we investigated differences in activity and sleep levels among 17 Ae. aegypti lines drawn from both its native range in Africa and its invasive range across the global tropics. Activity monitoring indicates that all the lines show consistent diurnal activity, but significant differences in activity level, sleep amount, number of sleep bouts and bout duration were observed among the lines. The variation in day activity was associated with differences in host preference and ancestry for the lineages collected in Africa. This study provides evidence that the diurnal sleep and activity profiles for Ae. aegypti are consistent, but there are significant population differences for Ae. aegypti sleep and activity levels and interactions with host species may significantly impact mosquito activity. [ABSTRACT FROM AUTHOR]

Mosquito traps, historically used for surveillance and research, have gained prominence as a tool for mosquito control, amidst concern over the environmental impact and increased resistance to insecticide‐based methods. In this study, we tested the effectiveness of a mass trapping barrier design with two types of traps, Mosquito Magnet (MM) traps and BG‐Protector (BGP) traps. This experiment was conducted in three coastal camping areas in southern France between summer and autumn 2022, where the presence of floodwater mosquito species with anthropophilic preferences like Aedes caspius represents a year‐long nuisance. MM traps were set around the campsite as a barrier to interfere with mosquitoes from entering the campsites, whereas BGP traps were set within the campsites, with the aim of diverting mosquitoes away from humans at peak activity hours. Over 210,000 mosquitoes of 11 species from 4 genera were collected by both trap types across treatment campsites, with no significant differences in mosquito community samplings between BGP and MM traps. Barrier traps effectively targeted Ae. caspius, reducing total mosquito abundance in two of the three study sites by 34% and 55%. This study provides valuable insights into the efficacy and feasibility of using mass trapping barriers as a complementary control strategy for mosquito species in wetlands. [ABSTRACT FROM AUTHOR]

The mechanism of cytoplasmic incompatibility (CI) is important in the study of Wolbachia invasion in wild mosquitoes. Su et al. (Bull Math Biol 84(9):95, 2022) proposed a delay differential equation model by relating the CI effect to maturation delay. In this paper, we investigate the dynamics of this model by allowing the same density-dependent death rate and distinct density-independent death rates. Through analyzing the existence and stability of equilibria, we obtain the parameter conditions for Wolbachia successful invasion if the maternal transmission is perfect. While if the maternal transmission is imperfect, we give the ranges of parameters to ensure failure invasion, successful invasion and partially suppressing, respectively. Meanwhile, numerical simulations indicate that the system may exhibit monostable and bistable dynamics when parameters vary. Particularly, in the bistable situation an unstable separatrix, like a line, exists when choosing constant functions as initial values; and the maturation delay affects this separatrix in an interesting way. [ABSTRACT FROM AUTHOR]

BACKGROUND: Spinosad consists of spinosyn A and spinosyn D that are produced by the soil‐dwelling actinomycete Saccharopolyspora spinosa. It has been used to control a wide variety of arthropod pests of economic importance. Formulations of spinosad have been used to control larval mosquitoes since approximately 2010. However, the target site‐ and metabolism‐based resistance to this neurotoxin has been reported since 2000 in agricultural pests The current studies aim to further evaluate resistance risk and develop resistance prevention tactics in the southern house mosquito Culex quinquefasciatus. RESULTS: The first comparison group involved selection at lethal concentration, 75% (LC75) of technical spinosad for 30 generations, resulting in baseline resistance ratios (RRs) of 51.1‐fold at LC50 and 45.4‐fold at LC90 in Cx. quinquefasciatus. However, under the same conditions, selection by a combination of spinosad and Bacillus thuringiensis subsp. israelensis (B.t.i.), negated resistance development to spinosad, RRs ranging 1.00–1.75‐fold at LC50 and 0.83–1.76‐fold at LC90. At the same time, the selected population remained susceptible to the combination throughout the selection process, RRs fluctuating 0.74–1.38‐fold at LC50 and 0.63–1.23‐fold at LC90. CONCLUSION: Combination of spinosad and B.t.i. negates resistance development to spinosad, as opposed to spinosad alone in Cx. quinquefasciatus. Moreover, the species tested does not develop resistance to this combination upon repeated exposures, implying the potential for further developing this combination as a viable product for larval mosquito control. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The incompatible insect technique (IIT) has been used for Aedes mosquito population suppression to curb the transmission of dengue. However, its wide application is limited owing to the low output of male mosquitoes and the risk of population replacement from the release of fertile Wolbachia‐infected females. This study aims to improve IIT efficiency for broader adoption. RESULTS: We assessed the impact of 10% pyriproxyfen (PPF) sticky powder exposure on Wolbachia (from Culex molestus)‐transinfected Aedes albopictus Guangzhou line (GUA line) (GC) mosquitoes. We found that the exposure caused chronic toxicity in adult mosquitoes without affecting the cytoplasmic incompatibility (CI)‐inducing capability of males. The PPF‐contaminated GC females exhibited significant sterilization and the ability to disseminate lethal doses of PPF to breeding sites. Subsequently, we conducted a field trial combining PPF with IIT aiming to suppress the Ae. albopictus population. This combined approach, termed boosted IIT (BIIT), showed a notable enhancement in population suppression efficiency. The improved efficacy of BIIT was attributed to the dispersion of PPF particles in the field via the released PPF‐contaminated male mosquitoes. During the BIIT field trial, no Wolbachia wPip‐positive Ae. albopictus larvae were detected, indicating the effective elimination of the risk of Wolbachia‐induced population replacement. Additionally, the field trial of BIIT against Ae. albopictus resulted in the suppression of the nontarget mosquito species Culex quinquefasciatus. CONCLUSION: Our results highlight the remarkable efficiency and feasibility of combining IIT with PPF in suppressing mosquito populations, facilitating the widespread implementation of IIT‐based management of mosquito‐borne diseases. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Abstract Humans have greatly altered earth’s terrestrial water cycle with the majority of fresh water being used for agriculture. Irrigation changes spatial and temporal water availability and alters mosquito abundance and phenology. Previous studies evaluating the effect of irrigation on mosquito abundance and mosquito-borne disease have shown inconsistent results and little is known about the effect of irrigation on variability in mosquito abundance. We examined the effect of irrigation, climate and land cover on mosquito abundance and human West Nile virus (WNV) disease cases across California. Irrigation made up nearly a third of total water inputs, and exceeded precipitation in some regions. Abundance of two key vectors of several arboviruses, including WNV, Culex tarsalis and the Culex pipiens complex, increased 17–21-fold with irrigation. Irrigation reduced seasonal variability in C. tarsalis abundance by 36.1%. Human WNV incidence increased with irrigation, which explained more than a third (34.2%) of the variation in WNV incidence among California counties. These results suggest that irrigation can increase and decouple mosquito populations from natural precipitation variability, resulting in sustained and increased disease burdens. Shifts in precipitation due to climate change are likely to result in increased irrigation in many arid regions which could increase mosquito populations and disease.

Culex interrogator is a culicid species that has recently been reported in the insular Caribbean, first in Cuba, specifically in the province of Santiago de Cuba, and shortly afterward in the Dominican Republic. This study’s objective is to report for the first time the presence of Cx. interrogator in the Cuban province of Camagüey and investigate its larval breeding sites in the urban environment. In 2022, visual inspections were conducted in all dwellings and facilities in the municipality of Camagüey, including intra- and peridomiciliary areas in the urban and suburban regions. In each positive mosquito reservoir, as many larvae and pupae as possible were collected. A total of 30 samples positive for Cx. interrogator (n = 155 larvae) were collected from 13 types of reservoirs. Ditches were the most frequent reservoir with the species present (n = 8; 26.66%), followed by ground-level tanks and sewage pits (n = 4; 13.33% each). All positive reservoirs were located in outdoor areas of dwellings. The discovery of this mosquito species in Camagüey, with many unknown aspects of its role as a vector, highlights the need for close monitoring and in-depth study.

Abstract Due to limitations in conventional disease vector control strategies including the rise of insecticide resistance in natural populations of mosquitoes, genetic control strategies using CRISPR gene drive systems have been under serious consideration. The identification of CRISPR target sites in mosquito populations is a key aspect for developing efficient genetic vector control strategies. While genome-wide Cas9 target sites have been explored in mosquitoes, a precise evaluation of target sites focused on coding sequence (CDS) is lacking. Additionally, target site polymorphisms have not been characterized for other nucleases such as Cas12a, which require a different DNA recognition site (PAM) and would expand the accessibility of mosquito genomes for genetic engineering. We undertook a comprehensive analysis of potential target sites for both Cas9 and Cas12a nucleases within the genomes of natural populations of Anopheles gambiae and Aedes aegypti from multiple continents. We demonstrate that using two nucleases increases the number of targets per gene. Also, we identified differences in nucleotide diversity between North American and African Aedes populations, impacting the abundance of good target sites with a minimal degree of polymorphisms that can affect the binding of gRNA. Lastly, we screened for gRNAs targeting sex-determination genes that could be widely applicable for developing field genetic control strategies. Overall, this work highlights the utility of employing both Cas9 and Cas12a nucleases and underscores the importance of designing universal genetic strategies adaptable to diverse mosquito populations.

Cu/CuO nanoparticles (NPs) have received extensive attention owing to their tremendous antifungal and antibacterial properties. Cu/CuO NPs are used in diverse fields, viz. electronics, catalysis, photonics, biosensing, optoelectronics and many more. Herein, we described the green synthesis of Cu/CuO NPs using Cuscuta reflexa (Amarvel) plant material at room temperature. The prepared NPs were characterized by routine technique, viz. XRD, UV-Vis, SEM and TEM. The typical size found was merely 7–10nm using the TEM technique. The as-prepared solution of NPs was tested against the Diptera larval nymph of mosquitoes. These mosquitoes breed in monsoon (rainy season) in stagnant water. It is observed that NPs were very effective against these larvae, which were killed overnight when just four drops of the as-prepared NPs solution were directly added to a 10ml water sample containing mosquito larvae. Overall, the biosynthesized Cu/CuO NPs showed good insecticidal activity against the parasitic disease malaria-causing Anopheles mosquitoes in the larval stage itself. We believe the outcome will lead to a new era in the preparation of innovative organic insecticides. [ABSTRACT FROM AUTHOR]

The detection of insecticide resistance in male mosquitoes has been treated with less importance in monitoring insecticide resistance spread in mosquitoes. There are no studies on the susceptibility and synergistic activity of DDT and lambda-cyhalothrin on male Anopheles gambiae and Aedes aegypti in Delta State, Nigeria. Even though studies have extensively reported resistance in female mosquitoes, the susceptibility of male mosquitoes to insecticide classes should be ascertained. In this study, we tested the susceptibility status and synergistic activity of DDT and Lambda-cyhalothrin on An. gambiae and Ae. aegypti in Delta State, Nigeria, in order to ascertain the level of resistance and knockdown. In addition, we modelled the knockdown time using Probit analysis model. WHO bioassay method was used to expose two days old adult mosquitoes to 4% DDT and 0.05% lambda-cyhalothrin. The results showed that An. gambiae mosquitoes exposed to DDT and lambda-cyhalothrin were confirmed resistant (61% and 53% respectively). However, pre-exposing the resistant mosquito population to piperonyl butoxide (4%) showed an increase in mortality to 90% (possible resistance) in DDT and 98% (susceptible) in lambda-cyhalothrin. Ae. aegypti mosquitoes exposed to DDT were susceptible (98%) while those exposed to lambda-cyhalothrin were confirmed resistant (87%) and this increased to complete mortality (100%) in PBO+lambda-cyhalothrin population. Furthermore, the results showed that the knockdown time (KDT50 and KDT95) in An. gambiae exposed to DDT was 39.5–71.2 minutes and 124.5–146.4 minutes respectively, while that of lambda-cyhalothrin was 33.0–81.8 minutes and 64.0–124.4 minutes respectively. In Ae. aegypti, KDT50 and KDT95 was 23.9 and 61.7minutes for DDT exposure whereas it was 5.6–15.3 minutes and 36.1–72.3 minutes for lambda-cyhalothrin exposure. It can be concluded that male An. gambiae mosquitoes exposed to the insecticides were resistant and the causes may be linked to certain resistant genes in the mosquitoes. The chances of transferring resistance are possible in wild species and molecular-based studies on the resistant gene in male mosquitoes as well as the tendencies of transfer are required to establish this focus. [ABSTRACT FROM AUTHOR]

Background: Aedes albopictus is a major arbovirus vector with small stagnant water containers being its oviposition sites. Mosquitoes search for these sites based on their olfactory cues (odor and moisture emanating from the water at the oviposition site), visual cues (size and color of the site), and gustatory cues (ion and nutrient concentration in that water). The gustatory mechanism through which mosquitoes search for oviposition sites remains unknown. Methods: To investigate the role of taste receptors in Ae. albopictus oviposition site selection, we developed a laboratory model. This model assessed mosquito behavior in locating and detecting oviposition sites, using a location index to quantify site preference and detection time to measure response to water presence. We compared oviposition site-searching efficiency between mosquitoes with blocked and unblocked appendages, targeting the taste organs. Transcriptome sequencing was conducted to identify differentially expressed genes between water-exposed and unexposed mosquitoes. CRISPR/Cas9 technology was then employed to generate a mutant strain with a targeted gene knockout. Results: There was no significant difference between the blocked and unblocked groups in the location index. In contrast, the detection time of the unblocked group differed significantly from all other groups, including those with blocked foreleg tarsus, midleg tarsus, hindleg tarsus, all tibia, and all tarsus. Transcriptome sequencing analyses of water-exposed and unexposed mosquitoes revealed that the taste-related gene gustatory receptor 11(gr11) was differentially expressed. This gene was knocked out with CRISPR/Cas9 technology to generate a pure mutant strain with 2- and 4-bp deletions, which exhibited a significantly longer detection time than the wild-type strain. Conclusions: This study reveals the role of Ae. albopictus gr11 in water detection at oviposition sites, thereby providing a theoretical basis and scientific guidelines for managing the breeding sites of these mosquitoes. [ABSTRACT FROM AUTHOR]

Background: Understanding the relationship between blood-feeding and mating is important in effectively managing the most well-adapted vector insect, Aedes aegypti (Linnaeus). Although extensive studies have investigated the behavioural aspects of Aedes such as blood-feeding, mating, and their relationship, several knowledge gaps still exist. Therefore, the present study was undertaken to determine the possibility of successful mating by unfed, engorged, and partially to fully gravid (up to 5 days after blood-feeding with fully developed eggs) female Ae. aegypti mosquitoes and production of viable eggs. Methods: Mating of sexually mature adult Aedes aegypti was allowed in three different ways. In control 1, the females were allowed to mate before taking blood meal, and in control 2, the females were not at all allowed to mate. In the experiment, the females were separated into six categories, viz. D-0 to D-5. In D-0, the females were allowed to mate immediately after the bloodmeal and, in D-1, the females were allowed to mate on the first day of blood feeding, likewise, the females of D-2, D-3, D-4 and D-5 were allowed to mate on 2nd, 3rd, 4th and 5th day of blood feeding. Ovitrap was uniformly kept on the 4th day of blood feeding for the cages D-0 to D-3 for 1 h and then removed and for the cages D-4, and D-5, the ovitrap was kept on 4th and 5th day of blood feeding for 1h immediately after mating. The total number of eggs and the total number of hatching were counted. In the subsequent days, the entire experiment was replicated two times with different cohorts of mosquitoes, and the mean value of three experiments was used to draw Excel bars with 5% error bars and also for the statistical analysis. Results: It was found that mating just before oviposition was sufficient to produce 1581 eggs (70% compared with control) and fertilize 1369 eggs (85% compared with total eggs laid), which is far higher than the 676 non-hatching (unfertilized) eggs (30%) laid by unmated females. Although mating is not essential for producing eggs, our study shows that even brief exposure to the semen and seminal fluids greatly enhances the oviposition and hatching efficiency, even if the mating occurs just before oviposition. However, those females mating before blood-feeding and those mating after blood-feeding produced 2266 and 2128 eggs, with hatching rates of 96.78% and 95.54%, respectively. Hence, the retention time of seminal fluid in the female seems to influence the number of eggs laid and the number of eggs hatched. Conclusions: In general, mating is possible in Ae. aegypti even minutes before oviposition and is sufficient to produce a greater number of viable eggs. [ABSTRACT FROM AUTHOR]

Beauveria bassiana has potential for Aedes aegypti biological control. However, its efficacy depends on the strain's geographic location, host susceptibility, and virulence. The present study aimed to evaluate the effectiveness of B. bassiana strain BBPTG4 conidia in controlling Ae. aegypti adults and its detection via introns profile on exposed mosquito corpses. Morphologic characteristics among strains were highly similar. Comprehensive testing of these strains demonstrated that BBPT4 exhibited the ideal biological activity for Ae. aegypti control, with a median lethal time (TL50) of 7.5 d compared to ~3 d and ~10 d for BB01 and BB37 strains, respectively. Infected mosquitoes died after GHA and BBPTG4 exposure, and corpses were analyzed for infecting strains detection. Differences among the seven evaluated strains were determined, assessing five different insertion group I intron profiles in BBTG4, BB01, GHA, BB37, and BB02 strains. Mosquitoes infected by BBPTG4 and non-exposed (negative control) intron profiles were obtained. We detected the presence of introns in the BBPTG4 strain, which were not present in non-exposed mosquitoes. In conclusion, B. bassiana strains showed similarities in terms of their cultural and microscopic morphological characteristics and biologicals virulence level, but different intron profiles. BBPTG4 strain-infected Ae. aegypti adult corpses, showing specific amplicons, enabled us to identify B. bassiana at the strain level among infected mosquitoes. However, monitoring and detection of field-infected insects is essential for further verification. [ABSTRACT FROM AUTHOR]

A major global health problem continues to be malaria, a disease that can be fatal brought on by Plasmodium parasites and spread by the bite of infected Anopheles mosquitoes. We provide a deterministic mathematical model in this study to simulate the dynamics of malaria transmission between humans and mosquitoes. We present a new compartment for hospitalized patients as well as fractional calculus. The next-generation matrix technique is used to obtain the fundamental reproduction number, R 0 , and stability conditions for the model's equilibrium points are derived. Both locally and globally, the sensitivity analysis for the fundamental reproduction number R 0 is satisfied. In MAPLE, the Runge–Kutta fourth-order approach is used to simulate the model. [ABSTRACT FROM AUTHOR]

Aedes albopictus is an important vector of arboviruses and prefers small containers of stagnant water as oviposition sites. One of the mechanisms mosquitoes use to search for suitable oviposition sites is relying on odor cues from prospective sites and their surroundings. The genetic and molecular bases of this behavior are not known for Ae. albopictus. Oviposition site‐searching behavior can be separated into 2 stages: container location and water detection. We applied a glue compound to the antennae and the maxillary palps of adult females to mask their ability to detect molecules that may guide them to preferred oviposition sites. Treatment of the antennae significantly reduces the location index (P < 0.001), indicating a decreased ability to find oviposition sites, whereas no significant difference was observed in mosquitoes with maxillary palps treated with the same glue compound (P > 0.05). The detection time, measured as the duration from contact with the water surface to the deposition of the first egg, was extended in mosquitoes with treated antennae or maxillary palps, supporting the conclusion that olfaction is involved in the detection of oviposition site. Transcriptomic analysis identified differentially expressed olfactory‐related genes, including obp67, obp56d‐like, obp19d‐like and obp67‐like. RNA interference (RNAi)‐mediated knockdown of obp67 and obp56d‐like significantly affected the location index and detection time, respectively. Cas9/guide RNA‐mediated knockout of obp56d‐like resulted in a prolonged detection time, compared with the wild type (P < 0.05). These findings help to elucidate aspects of the olfactory mechanisms involved in Ae. albopictus oviposition site selection, and provide a basis for the development of mosquito surveillance and control strategies. [ABSTRACT FROM AUTHOR]

Anopheles stephensi Liston, 1901 (Diptera: culicidae) is a competent vector of Plasmodium falciparum (Haemosporida: plasmodiidae) malaria, and its expansion in the African continent is of concern due to its viability in urban settings and resistance to insecticides. To enhance its genetic tractability, we determined the utility of a ~2 kb An. stephensi lipophorin (lp) promoter fragment in driving transgene expression. Lipophorin genes are involved in lipid transport in insects, and an orthologous promoter in An. gambiae (AGAP001826) was previously demonstrated to successfully express a transgene. In the present study, we qualitatively characterised the expression of a ZsYellow fluorescent marker protein, expressed by An. stephensi lp promoter fragment. Our study indicated that the lp promoter fragment was effective, generating a distinct expression pattern in comparison to the commonly utilised 3xP3 promoter. The lp:ZsYellow fluorescence was largely visible in early instar larvae and appeared more intense in later instar larvae, pupae and adults, becoming especially conspicuous in adult females after a blood meal. Different isolines showed some variation in expression pattern and intensity. Aside from general transgene expression, as the lp promoter produces a suitable fluorescent protein marker expression pattern, it may facilitate genotypic screening and aid the development of more complex genetic biocontrol systems, such as multi‐component gene drives. This study represents an expansion of the An. stephensi genetic toolbox, an important endeavour to increase the speed of An. stephensi research and reach public health milestones in combating malaria. [ABSTRACT FROM AUTHOR]

We present a rigorous mathematical analysis of a non‐convex optimal control problem for mosquito populations. The nonlinear model for the dynamics of the mosquito population takes in consideration the iterations among the immature (aquatic) subpopulation, the adult winged subpopulation, and the environment resources; the immature subpopulation is assumed to be age‐structured. Moreover, the action of certain control mechanisms on these subpopulations is also taken in account. The cost functional to be minimized is non‐convex. The proof of the existence of an optimal control is done by using fixed point arguments and a special minimizing sequence obtained with the help of Ekeland's variational principle. [ABSTRACT FROM AUTHOR]

Mosquitoes such as Aedes aegypti must consume a blood meal for the nutrients necessary for egg production. Several transcriptome and proteome changes occur post‐blood meal that likely corresponds with codon usage alterations. Transfer RNA (tRNA) is the adapter molecule that reads messenger RNA codons to add the appropriate amino acid during protein synthesis. Chemical modifications to tRNA enhance codon decoding, improving the accuracy and efficiency of protein synthesis. Here, we examined tRNA modifications and transcripts associated with the blood meal and subsequent periods of vitellogenesis in A. aegypti. More specifically, we assessed tRNA transcript abundance and modification levels in the fat body at critical times post blood‐feeding. Based on a combination of alternative codon usage and identification of particular modifications, we discovered that increased transcription of tyrosine tRNAs is likely critical during the synthesis of egg yolk proteins in the fat body following a blood meal. Altogether, changes in both the abundance and modification of tRNA are essential factors in the process of vitellogenin production after blood‐feeding in mosquitoes. [ABSTRACT FROM AUTHOR]

Insect growth regulators, like S-methoprene, are heavily relied upon worldwide for larval mosquito chemical control due to their target specificity and long-lasting effects. In this study, susceptibility to S-methoprene was evaluated in Culex pipiens, a globally important vector species. Populations from 14 sites throughout the Chicago area with a long history of S-methoprene use and two sites with minimal use in Wisconsin were examined. Using a bioassay methodology and probit analyses, LC50 and LC90 values were calculated and compared to a susceptible laboratory strain to develop resistance ratios, then categorized for resistance intensity. The resistance ratios observed required the addition of another category, termed 'extreme' resistance, indicating resistance ratios greater than 100. 'Low' to 'extreme' levels of resistance to S-methoprene were detected throughout Illinois populations, with resistance ratios ranging from 2.33 to 1010.52. Resistance was not detected in populations where S-methoprene pressure has been very limited. These 'extreme' resistance ratios observed have never been documented in a wild vector species mosquito population. The relationships between historical S-methoprene use, resistance detected with laboratory bioassays, and the potential for field product failure remain unclear. However, the profound resistance detected here demonstrates a potential critical threat to protecting public health from mosquito-borne diseases. [ABSTRACT FROM AUTHOR]

Aedes albopictus (Skuse, 1895), the Asian tiger mosquito extended globally in just a few decades from Asia showing great adaptability despite temperature-dependent development. The present study revealed the effects of temperature (20 ℃, 26 ℃, 30 ℃, and 35 ℃) on various developmental parameters of Ae. albopictus strains belonging to the desert (Jodhpur, Rajasthan) and the coastal (Kolkata, West Bengal) regions of India. The desert strain developed faster from eggs-adult emergence (7.5 days at 35 ℃ and 14.0 days at 20 ℃) than the coastal strain (7.8 days at 35 ℃ and 16.8 days at 20 ℃). The survival was highest and lowest at 26 °C and 35 ℃, respectively, irrespective of strains and stages. The larval survival trends of both strains were similar to pupae across the temperature range. The wing length of the desert strain was shorter in comparison to the coastal strain. Wing length was found inversely proportional to the temperature being longest at 20 ℃ and the shortest at 35 ℃ for both strains. Male and female wing lengths were larger (25% and 22.7% in the Jodhpur strain and 24.6% and 23.6% in the Kolkata strain) at 20 ℃ compared to 35 ℃, respectively. Significant differences were observed between the male-female sex ratio in the coastal strain. The outcomes of the study suggest consideration of temperature impact on immature developmental attributes that might help in the refining of control measures and a better understanding of ecological adaptations in contrast to ecological conditions. [ABSTRACT FROM AUTHOR]

The present study investigated the relative abundance of mosquitoes larvae in three different breeding habitats in seven districts of Beni-Suef Governorate, Egypt during two years (2019–2020). The results showed that the species composition of mosquitoes was represented by four genera and eight species; four of Culex (Cx. pipiens Linnaeus,1758, Cx. theileri Theobald,1903, Cx. perexiguus Theobald, 1903 and Cx. antennatus (Becker,1903)), two of Anopheles (An. coustani Laveran, 1900 and An. multicolor Cambouliu, 1902) and one each of Aedes and Culiseta (Ae. caspius (Pallas, 1771) and Cs. longiareolata (Macquart, 1838)). The results were demonstrated also, that Cx. pipiens (4934 larvae) was the most common species, followed by Cx. perexiguus (2991 larvae) in all breeding habitats. Particularly, this species distributed in drains more than irrigation tanks and agriculture canals, the other species of Anopheles and Aedes were very little or absence in all test breeding habitats. The densities of almost mosquitoes species with higher collections were found in Saft, Elfant and El-Maimun villages and rate of collection decreased in Tizmant and Bedahl. These information on the species composition and their abundance of mosquitoes in Beni-Suef may help better planning for the integrated pest management for these vectors and transmitted diseases. [ABSTRACT FROM AUTHOR]

Climate change will alter interactions between parasites and their hosts. Warming may affect patterns of local adaptation, shifting the environment to favor the parasite or host and thus changing the prevalence of disease. We assessed local adaptation to hosts and temperature in the facultative ciliate parasite Lambornella clarki , which infects the western tree hole mosquito Aedes sierrensis. We conducted laboratory infection experiments with mosquito larvae and parasites collected from across a climate gradient, pairing sympatric or allopatric populations across three temperatures that were either matched or mismatched to the source environment. Lambornella clarki parasites were locally adapted to their hosts, with 2.6 times higher infection rates on sympatric populations compared with allopatric populations, but they were not locally adapted to temperature. Infection peaked at the intermediate temperature of 12.5°C, notably lower than the optimum temperature for free-living L. clarki growth, suggesting that the host's immune response can play a significant role in mediating the outcome of infection. Our results highlight the importance of host selective pressure on parasites, despite the impact of temperature on infection success. [ABSTRACT FROM AUTHOR]

Recent reports have disclosed the occurrence of Wolbachia in Aedes aegypti. Our study detected Wolbachia infection in Ae. aegypti by screening wild adult mosquitoes using two Wolbachia‐specific molecular markers. Overall, 444 adult Ae. aegypti mosquitoes were collected from April 2022 to October 2022 in Jeddah, Saudi Arabia. Each individual sample was processed and screened for the presence of Wolbachia using selected markers, the Wolbachia‐specific 16S rDNA and the Wolbachia surface protein gene (wsp), under optimized polymerase chain reaction (PCR) conditions, and sequenced. In total, 39 (8.78%) and 48 (10.81%) individual mosquito samples were determined to be infected with Wolbachia using the wsp and 16S rDNA markers, respectively. By utilizing two Wolbachia‐specific molecular markers, our study demonstrated the presence of Wolbachia from individual Ae. aegypti samples. Our results showed a low rate of Wolbachia infection and inferred that the detected strain belongs to supergroup B. [ABSTRACT FROM AUTHOR]

Culex tarsalis Coquillett (Diptera: Culicidae) mosquitoes are capable of vectoring numerous pathogens affecting public and animal health. Unfortunately, the probing behaviors of mosquitoes are poorly understood because they occur in opaque tissues. Electropenetrography (EPG) has the potential to elucidate these behaviors by recording the electrical signals generated during probing. We used an AC–DC EPG with variable input resistors (Ri levels) to construct a waveform library for Cx. tarsalis feeding on human hands. Biological events associated with mosquito probing were used to characterize waveforms at four Ri levels and with two electrical current types. The optimal settings for EPG recordings of Cx. tarsalis probing on human hands was an Ri level of 107 Ohms using an applied signal of 150 millivolts alternating current. Waveforms for Cx. tarsalis included those previously observed and associated with probing behaviors in Aedes aegypti L. (Diptera: Culicidae): waveform families J (surface salivation), K (stylet penetration through the skin), L (types 1 and 2, search for a blood vessel/ingestion site), M (types 1 and 2, ingestion), N (type 1, an unknown behavior which may be a resting and digestion phase), and W (withdrawal). However, we also observed variations in the waveforms not described in Ae. aegypti, which we named types L3, M3, M4, and N2. This investigation enhances our understanding of mosquito probing behaviors. It also provides a new tool for the automated calculation of peak frequency. This work will facilitate future pathogen acquisition and transmission studies and help identify new pest and disease management targets. [ABSTRACT FROM AUTHOR]

Front cover: Female mosquitoes suck blood to mature their eggs. It has been reported that fi brinopeptide A (FPA), which is cleaved from fi brinogen α chain during blood coagulation, makes mosquitoes feel "full" and stop sucking blood (Sakuma et al. (2024) Cell Reports 43: 114354, DOI: 10.1016/j.celrep.2024.114354). The mother in this painting is trying to use a mosquito net imbued with the ability of FPA to override the child's nightmare of a bloodsucking mosquito with the image of a satiated mosquito. In addition to fi brinogen and FPA, the mother's kimono shows schematic images of fi brin that has just begun to coagulate. Designed by TRAIS Co., Ltd. (Kobe, Japan). [ABSTRACT FROM AUTHOR]

Wolbachia symbionts introduced into Aedes mosquitoes provide a highly effective dengue virus transmission control strategy, increasingly utilised in many countries in an attempt to reduce disease burden. Whilst highly effective against dengue and other positive-sense RNA viruses, it remains unclear how effective Wolbachia is against negative-sense RNA viruses. Therefore, the effect of Wolbachia on Bunyamwera virus (BUNV) infection in Aedes aegypti was investigated using wMel and wAlbB, two strains currently used in Wolbachia releases for dengue control, as well as wAu, a strain that typically persists at a high density and is an extremely efficient blocker of positive-sense viruses. Wolbachia was found to reduce BUNV infection in vitro but not in vivo. Instead, BUNV caused significant impacts on density of all three Wolbachia strains following infection of Ae. aegypti mosquitoes. The ability of Wolbachia to successfully persist within the mosquito and block virus transmission is partially dependent on its intracellular density. However, reduction in Wolbachia density was not observed in offspring of infected mothers. This could be due in part to a lack of transovarial transmission of BUNV observed. The results highlight the importance of understanding the complex interactions between multiple arboviruses, mosquitoes and Wolbachia in natural environments, the impact this can have on maintaining protection against diseases, and the necessity for monitoring Wolbachia prevalence at release sites. [ABSTRACT FROM AUTHOR]

Studies on animal virome have mainly concentrated on chordates and medically significant invertebrates, often overlooking sylvatic mosquitoes, constituting a major part of mosquito species diversity. Despite their potential role in arbovirus transmission, the viromes of sylvatic mosquitoes remain largely unexplored. These mosquitoes may also harbor insect-specific viruses (ISVs), affecting arboviral transmission dynamics. The Cerrado biome, known for rapid deforestation and its status as a biodiversity hotspot, offers an ideal setting for investigating mosquito viromes due to potential zoonotic spillover risks from land use changes. This study aimed to characterize the viromes of sylvatic mosquitoes collected from various locations within Minas Gerais state, Brazil. The total RNA was extracted from mosquito pools of Psorophora albipes, Sabethes albiprivus, Sa. chloropterus, Psorophora ferox, and Coquillettidia venezuelensis species, followed by high-throughput sequencing (HTS). Bioinformatic analysis included quality control, contig assembly, and viral detection. Sequencing data analysis revealed 11 near-complete viral genomes (new viruses are indicated with asterisks) across seven viral families and one unassigned genus. These included: Xinmoviridae (Ferox mosquito mononega-like virus* and Albipes mosquito Gordis-like virus*), Phasmaviridae (Sabethes albiprivus phasmavirus*), Lispiviridae (Pedras lispivirus variant MG), Iflaviridae (Sabethes albiprivus iflavivirus*), Virgaviridae (Buriti virga-like virus variant MG and Sabethes albiprivus virgavirus 1*), Flaviviridae (Psorophora ferox flavivirus*), Mesoniviridae (Alphamesonivirus cavallyense variant MG), and the genus Negevirus (Biggie virus variant MG virus and Coquillettidia venezuelensis negevirus*). Moreover, the presence of ISVs and potential novel arboviruses underscores the need for ongoing surveillance and control strategies to mitigate the risk of emerging infectious diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: The main mosquito species capable of transmitting arboviruses belong to the genera Aedes spp., Psorophora spp., Anopheles spp., Culex spp., Mansonia spp., Coquillettidia spp., Haemagogus spp., Sabethes spp., Culiseta spp., and Wyeomyia spp. Some neglected mosquito species have the potential to become significant disease vectors due to parameters such as global distribution, rapid adaptation to urban areas, and anthropophilic habits. This review discusses the epidemiological importance and biology of three neglected mosquitoes, Aedes scapularis, Aedes vittatus, and Aedes japonicus japonicus, in the context of vectorial capacity and how urbanization, climate change, and globalization alter disease transmission dynamics and may increase the participation of neglected species in propagating diseases. More than 3550 species of mosquitoes are known worldwide, and only a fraction is involved in the transmission of arboviruses. Mosquitoes in sylvatic and semi-sylvatic habitats may rapidly adapt to urban parks and metropolitan environments, increasing human contact. Many of these mosquitoes have been found naturally infected with arboviruses from the Alphaviridae, Flaviviridae, and Bunyaviridae families, with many being the cause of medically important diseases. However, there is a gap in knowledge about the vector status of newly invasive species and their potential threat to human and domestic animal populations. Due to their rapid distribution, adaptation to urban environments, and anthropophilic habits, some neglected mosquito species may deserve more attention regarding their role as secondary vectors. Taking these factors into account, we focus here on Aedes (Ochlerotatus) scapularis (Rondani), Aedes japonicus japonicus (Theobald), and Aedes (Fredwardsius) vittatus (Bigot) as species that have the potential to become important disease vectors. We further discuss the importance of these neglected mosquitoes and how factors such as urbanization, climate change, and globalization profoundly alter the dynamics of disease transmission and may increase the participation of neglected species in propagating diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: Over the last decade, optical sensors have demonstrated great potential to provide complementary data to monitor insect abundance. This article introduces a field-deployable and non-destructive optical instrument to monitor the abundance of flying insects, called an Entomological Bistatic Optical Sensor System, or eBoss. The study focuses on comparing abundance measurements made by the eBoss and physical traps over an 8-month field campaign. The eBoss made over 302,000 insect observations and evaluated the aerial density (#/m3) of all flying insects as well as specifically male and female mosquitoes with a 1 min resolution, allowing us to monitor both the abundance over the season and daily peak of activity. The study's objectives were to validate the optical sensor's data against physical trap collections, which confirmed the correlation between the two methods. However, the eBoss demonstrated superior temporal resolution (1 min versus approximately 3 days) and statistical power due to its larger sample size. These findings suggest that an eBoss can significantly enhance flying insect monitoring efforts, such as mosquitoes or pollinators, providing valuable insights for vector control strategies, agriculture and public health planning. Optical sensors have shown significant promise in offering additional data to track insect populations. This article presents a comparative study between abundance measurements obtained from a novel near-infrared optical sensor and physical traps. The optical instrument, named an Entomological Bistatic Optical Sensor System, or eBoss, is a non-destructive sensor operating in the near-infrared spectral range and designed to continuously monitor the population of flying insects. The research compares the mosquito aerial density (#/m3) obtained through the eBoss with trap counts from eight physical traps during an eight-month field study. The eBoss recorded over 302,000 insect sightings and assessed the aerial density of all airborne insects as well as male and female mosquitoes specifically with a resolution of one minute. This capability allows for monitoring population trends throughout the season as well as daily activity peaks. The results affirmed the correlation between the two methods. While optical instruments do not match traps in terms of taxonomic accuracy, the eBoss offered greater temporal resolution (one minute versus roughly three days) and statistical significance owing to its much larger sample size. These outcomes further indicate that entomological optical sensors can provide valuable complementary data to more common methods to monitor flying insect populations, such as mosquitoes or pollinators. [ABSTRACT FROM AUTHOR]

In control of wild mosquitoes to fight mosquito-borne diseases, release of mosquitoes with Wolbachia is one of the effective biological control methods. There are three release strategies, namely releasing both Wolbachia-infected females and males, only Wolbachia-infected females and only Wolbachia-infected males. All these three strategies have been confirmed to be capable of speeding up the Wolbachia persistence in mosquito populations. In this paper, we investigate how supplementary releases affect the Wolbachia spread dynamics in mosquito populations. Our aim is to compare the effectiveness among these three release strategies. We obtain theoretical results and provide numerical simulations that show that the first two strategies are more effective than the last strategy. For the first two strategies, the former strategy is either less effective than the latter strategy in each generation, or more effective than the latter strategy in previous generations, and then becomes less effective in late generations. [ABSTRACT FROM AUTHOR]

Multiple Wolbachia strains can block pathogen infection, replication and/or transmission in Aedes aegypti mosquitoes under both laboratory and field conditions. However, Wolbachia effects on pathogens can be highly variable across systems and the factors governing this variability are not well understood. It is increasingly clear that the mosquito host is not a passive player in which Wolbachia governs pathogen transmission phenotypes; rather, the genetics of the host can significantly modulate Wolbachia‐mediated pathogen blocking. Specifically, previous work linked variation in Wolbachia pathogen blocking to polymorphisms in the mosquito alpha‐mannosidase‐2 (αMan2) gene. Here we use CRISPR‐Cas9 mutagenesis to functionally test this association. We developed αMan2 knockouts and examined effects on both Wolbachia and virus levels, using dengue virus (DENV; Flaviviridae) and Mayaro virus (MAYV; Togaviridae). Wolbachia titres were significantly elevated in αMan2 knockout (KO) mosquitoes, but there were complex interactions with virus infection and replication. In Wolbachia‐uninfected mosquitoes, the αMan2 KO mutation was associated with decreased DENV titres, but in a Wolbachia‐infected background, the αMan2 KO mutation significantly increased virus titres. In contrast, the αMan2 KO mutation significantly increased MAYV replication in Wolbachia‐uninfected mosquitoes and did not affect Wolbachia‐mediated virus blocking. These results demonstrate that αMan2 modulates arbovirus infection in A. aegypti mosquitoes in a pathogen‐ and Wolbachia‐specific manner, and that Wolbachia‐mediated pathogen blocking is a complex phenotype dependent on the mosquito host genotype and the pathogen. These results have a significant impact for the design and use of Wolbachia‐based strategies to control vector‐borne pathogens. [ABSTRACT FROM AUTHOR]

Background: Kadipiro virus (KDV) is a species of the new 12 segmented RNA virus grouped under the genus Seadornavirus within the Reoviridae family. It has previously been isolated or detected from mosquito, Odonata, and bat feces in Indonesia, China, and Denmark, respectively. Here, we describe the isolation and characterization of a viral strain from mosquitoes in Yunnan Province, China. Methods: Mosquitoes were collected overnight using light traps in Shizong county, on July 17, 2023. Virus was isolated from the mosquito homogenate and grown using baby hamster kidney and Aedes albopictus (C6/36) cells. Preliminary identification of the virus was performed by agarose gel electrophoresis (AGE). The full-genome sequences of the strain were determined by full-length amplification of cDNAs and sequenced using next-generation sequencing. Results: We isolated a viral strain (SZ_M48) from mosquitoes (Culex tritaeniorhynchus Giles) that caused cytopathogenic effects in C6/36 cells. AGE analysis indicated a genome consisting of 12 segments of double-stranded RNA that demonstrated a "6-5-1" pattern, similar to the migrating bands of KDV. Phylogenetic analysis based on the full-genome sequence revealed that SZ_M48 is more clustered with KDV isolates from Hubei and Shangdong in China than with Indonesian and Danish strains. The identity between SZ_M48 and SDKL1625 (Shandong, China) is slightly lower than that of QTM27331 (Hubei, China), and the identity with JKT-7075 (Indonesia) and 21164-6/M.dau/DK (Denmark) is the lowest. Conclusion: The full-genome sequence of the new KDV strain described in this study may be useful for surveillance of the evolutionary characteristics of KDVs. Moreover, these findings extend the knowledge about the genomic diversity, potential vectors, and the distribution of KDVs in China. [ABSTRACT FROM AUTHOR]

Background: West Nile virus (WNV), Everglades virus (EVEV), and five species of Orthobunyavirus were isolated from mosquitoes collected in the Everglades in 2016–2017. Prior studies of blood meals of mosquitoes in southern Florida have related findings to acquisition and transmission of EVEV, St. Louis encephalitis virus, and WNV, but not the Orthobunyavirus viruses associated with the subgenus Melanoconion of the genus Culex. Materials and Methods: In the present study, blood-fed mosquitoes were collected in the Everglades in 2016, 2017, 2021, and 2022, and from an industrial site in Naples, FL in 2017. Blood meals were identified to host species by PCR assays using mitochondrial cytochrome b gene. Results: Blood meals were identified from Anopheles crucians complex and 11 mosquito species captured in the Florida Everglades and from 3 species collected from an industrial site. The largest numbers of blood-fed specimens were from Culex nigripalpus, Culex erraticus, Culex cedecei, and Aedes taeniorhynchus. Cx. erraticus fed on mammals, birds, and reptiles, particularly American alligator. This mosquito species could transmit WNV to American alligator in the wild. Cx. nigripalpus acquired blood meals primarily from birds and mammals and frequently fed on medium-sized mammals and white-tailed deer. Water and wading birds were the primary avian hosts for Cx. nigripalpus and Cx. erraticus in the Everglades. Wading birds are susceptible to WNV and could serve as reservoir hosts. Cx. cedecei fed on five species of rodents, particularly black and hispid cotton rats. EVEV and three different species of Orthobunyavirus have been isolated from the hispid cotton rat and Cx. cedecei in the Everglades. Cx. cedecei is likely acquiring and transmitting these viruses among hispid cotton rats and other rodents. The marsh rabbit was a frequent host for An. crucians complex. An. crucians complex, and other species could acquire Tensaw virus from rabbits. Conclusions: Our study contributes to a better understanding of the host and viral associations of mosquito species in southwestern Florida. [ABSTRACT FROM AUTHOR]

Mosquitoes can transmit several pathogenic viruses to humans, but their natural viral community is also composed of a myriad of other viruses such as insect-specific viruses (ISVs) and those that infect symbiotic microorganisms. Besides a growing number of studies investigating the mosquito virome, the majority are focused on few urban species, and relatively little is known about the virome of sylvatic mosquitoes, particularly in high biodiverse biomes such as the Brazilian biomes. Here, we characterized the RNA virome of 10 sylvatic mosquito species from Atlantic forest remains at a sylvatic–urban interface in Northeast Brazil employing a metatranscriptomic approach. A total of 16 viral families were detected. The phylogenetic reconstructions of 14 viral families revealed that the majority of the sequences are putative ISVs. The phylogenetic positioning and, in most cases, the association with a high RNA-dependent RNA polymerase amino acid divergence from other known viruses suggests that the viruses characterized here represent at least 34 new viral species. Therefore, the sylvatic mosquito viral community is predominantly composed of highly divergent viruses highlighting the limited knowledge we still have about the natural virome of mosquitoes in general. Moreover, we found that none of the viruses recovered were shared between the species investigated, and only one showed high identity to a virus detected in a mosquito sampled in Peru, South America. These findings add further in-depth understanding about the interactions and coevolution between mosquitoes and viruses in natural environments. IMPORTANCE Mosquitoes are medically important insects as they transmit pathogenic viruses to humans and animals during blood feeding. However, their natural microbiota is also composed of a diverse set of viruses that cause no harm to the insect and other hosts, such as insect-specific viruses. In this study, we characterized the RNA virome of sylvatic mosquitoes from Northeast Brazil using unbiased metatranscriptomic sequencing and in-depth bioinformatic approaches. Our analysis revealed that these mosquitoes species harbor a diverse set of highly divergent viruses, and the majority comprises new viral species. Our findings revealed many new virus lineages characterized for the first time broadening our understanding about the natural interaction between mosquitoes and viruses. Finally, it also provided several complete genomes that warrant further assessment for mosquito and vertebrate host pathogenicity and their potential interference with pathogenic arboviruses. [ABSTRACT FROM AUTHOR]

A study was carried out in 345 water ecosystems (rivers, streams, ditches, lagoons, ponds, puddles, rockpools, and artificial containers) throughout the autonomous community of Galicia (NW Spain) during different seasons between 2020 and 2023. The results revealed the first detections of Anopheles (Anopheles) petragnani Del Vechio, 1939 (n  = 185) and Culex (Culex) mimeticus Noè, 1899 (n  = 12) in the territory, allowing to update and expand the overall knowledge about their distribution and ecology. The breeding preferences of the species were analyzed considering habitat characteristics (land use, water body type, and degree of insolation), geographical variables (latitude, longitude, and altitude), and physical–chemical water parameters (temperature, pH, dissolved oxygen, electrical conductivity, salinity, total dissolved solids, and turbidity). In addition, the relationship between the occurrence of these species and other mosquitoes present in the study area was discussed. Anopheles petragnani is widely distributed in the region and shows breeding preferences for water bodies of fluvial origin, forest environments, and shaded situations. Culex mimeticus was detected sporadically breeding in a pond and in a river in the south of the region, both in industrial and agricultural land uses, and always exposed to the sun. Although the presence of these species may not currently pose a health risk in the region, it is important not neglecting their study since the adequate characterization of their larval biotopes is relevant regarding vector surveillance and control measures. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) and nanoplastics (NPs) are pervasive environmental pollutants that are commonly ingested by organisms at different trophic levels. While the effects of MPs on aquatic organisms have been extensively studied, the impacts of MP ingestion on the host fitness of terrestrial organisms, mainly insects, have been relatively unexplored. This study investigates the effects of MP and NP ingestion on the survivorship and reproduction of 2 medically important mosquito species, Aedes aegypti Linnaeus (Diptera: Culicidae) and Aedes albopictus Skuse (Diptera: Culicidae). Larval and pupal survivorship of Ae. albopictus were not significantly affected by particle size or concentration, but there was a reduction of Ae. aegypti pupal survivorship associated with the ingestion of 0.03 µm NPs. In addition, there was little observed impact of 0.03 µm NP and 1.0 µm MP ingestion on adult survivorship, fecundity, and longevity. To further investigate the effects of MP ingestion on mosquito fitness, we also examined the effects of MPs of varying shape, size, and plastic polymer type on Ae. aegypti immature and adult survivorship. The data suggest that the polymer type and shape did not impact Ae. aegypti immature or adult survivorship. These findings highlight that understanding the effects of microplastic ingestion by mosquitoes may be complicated by the size, composition, and amount ingested. [ABSTRACT FROM AUTHOR]

In this paper, we explore and study a mosquito population suppression model, consisting of two sub-models switching each other, based on Wolbachia-infected mosquitoes. Under the assumptions that the releases of Wolbachia-infected males are impulsive and periodic and the waiting period between two consecutive releases is not less than the sexually active lifespan of Wolbachia-infected males, we give a fairly complete description of the periodic dynamics of the model including the nonexistence of periodic solutions and the existence of a unique periodic solution and exact two periodic solutions. We also analyze the asymptotic stability of each periodic solution and each constant equilibrium in detail. Finally, some numerical examples are provided to illustrate our theoretical results. [ABSTRACT FROM AUTHOR]

Background: Yellow fever (YF) remains a significant public health concern in Nigeria, with sporadic outbreaks causing considerable morbidity and mortality. This zoonotic viral disease is transmitted primarily by Aedes mosquitoes, posing a constant threat to human populations. Although vaccination efforts have been ongoing for years, outbreaks still occur, underscoring the need for a comprehensive approach to combat YF. In Nigeria, adopting a One Health approach is imperative for effective yellow fever control. This approach recognizes the intricate interplay between human health, animal health, and the environment. Key strategies include the implementation of travel advisories, widespread vaccination campaigns, and early detection and reporting of cases. Surveillance efforts extend to both human and non-human primate populations to monitor the circulation of the virus accurately. Community engagement plays a vital role in this approach, with local communities actively participating in efforts to eliminate mosquito breeding sites. Integrated mosquito management techniques, such as the use of insecticides and repellents, are promoted alongside community-led interventions to reduce breeding grounds, such as removing stagnant water. By embracing the principles of One Health and implementing coordinated efforts across regions within Nigeria, we can strive towards the eradication of yellow fever. This holistic approach holds the potential to mitigate the burden of disease and pave the way for a future free from the threat of yellow fever outbreaks in Nigeria. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Even though malaria has markedly reduced its global burden, it remains a serious threat to people living in or visiting malaria-endemic areas. The six Plasmodium species (Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, Plasmodium ovale curtisi, Plasmodium ovale wallikeri and Plasmodium knowlesi) are known to associate with human malaria by the Anopheles mosquito. Highlighting the dynamic nature of malaria transmission, the simian malaria parasite Plasmodium cynomolgi has recently been transferred to humans. The first human natural infection case of P. cynomolgi was confirmed in 2011, and the number of cases is gradually increasing. It is assumed that it was probably misdiagnosed as P. vivax in the past due to its similar morphological features and genome sequences. Comprehensive perspectives that encompass the relationships within the natural environment, including parasites, vectors, humans, and reservoir hosts (macaques), are required to understand this zoonotic malaria and prevent potential unknown risks to human health. [ABSTRACT FROM AUTHOR]

In recent years, light weight bio-inspired micro air vehicles (MAVs) have gained popularity due to wide applications in civil and military operations. Much research has been done in this regard inspired by the flapping wings of biological flyers such as birds, insects, bats, etc. MAVs have adapted the design from the flapping of beetle, butterfly, bat, hummingbird, mosquitoes, and bees. For MAV design, various flight characteristics such as wing beat frequency, Reynolds number, the aspect ratio of bio-mimic vehicle, landing, and take off techniques are examined. This article focuses on the recently developed bio-mimic MAVs and identifying their suitability for the desired task. The research accomplishments on the hoverable, insect, bird, and bat MAV mechanisms over the last decades are categorized and discussed. The mechanism's issues, trends, and difficulties are compiled and presented. This review concludes with recommendations for future research on the mechanical structures and mechanism. [ABSTRACT FROM AUTHOR]

BACKGROUNDS: In order to provide a long‐lasting formulation for spinosad (SP) targeting larval stages of Aedes aegypti (Linnaeus) and others alike, a SP tablet was developed based on microspheres, using polylactic acid as inside coating material. The microspheres were encapsulated using polyethylene glycol and 1‐hexadecanol to form a sustained‐release SP tablet. Micromorphology, active ingredient loading, structure identification, photolysis resistance and biological activity were evaluated in this report. RESULTS: (i) The SP microspheres had an average particle size of 6.16 ± 2.28 μm, low adhesion and good dispersion as evaluated by scanning electron microscopy and morphology. (ii) The average active ingredient loading and encapsulation of SP microspheres were 32.80 ± 0.74% and 78.41 ± 2.22%, respectively. (iii) The chemical structure of encapsulated SP was confirmed by Fourier transform infrared and 1H‐nuclear magnetic resonance. (iv) The photostability of the microspheres and the tablets were evaluated. The results showed that DT50 (time required to dissipate 50% of the mass originally present) of SP was 0.95 days in microspheres and 6.94 days in tablets. (v) The long‐term insecticidal activity of SP tablets was investigated, and the tablet had a long‐lasting activity against the mosquito larvae, showing 100% larval mortality for 63 days. CONCLUSIONS: The study provided a new long‐lasting formulation of SP, which displayed good efficacy in the control of Ae. aegypti larvae. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Dengue fever prevention and control is an urgent need for addressing major infectious diseases in China, and the control strategies need theoretical innovation and technological breakthroughs. Aedes albopictus, the dengue-borne mosquito, exhibits polymorphism in urban environments, resulting in heterogeneous mosquito habitats. This heterogeneity is evident in two aspects: firstly, varying mosquito densities across different habitats, and secondly, differences in vector competence of Aedes albopictus within the same city. The distribution of Aedes albopictus with high vector competence forms discrete "mosquito islands" within the city, analogous to small islands in the sea. Identifying the distribution and scope of these "mosquito islands", combined with vector Aedes daily activity rhythm and innovative ultra-low volume spray technology, can facilitate targeted mosquito control strategies during dengue outbreaks. This approach reduces insecticide spraying, improves mosquito control efficiency, and enables rapid dengue epidemic control. [ABSTRACT FROM AUTHOR]

Objective To analyze the epidemiological characteristics of dengue fever in Guangzhou and provide a scientific basis for dengue fever prevention and control. Methods The data of dengue cases in Guangzhou, Guangdong Province reported between 2019 and 2023, were retrieved from the China Disease Prevention and Control Information System. Cross-sectional analysis was used to describe the temporal, spatial, and demographic distribution, and analyze the epidemiological characteristics. Results A total of 3 518 cases of dengue fever were reported in Guangzhou from 2019 to 2023, including 3 101 local cases (88.15%) and 417 imported cases (11.85%). The annual average incidence rate ranged from 0.09 to 17.59 per 100 000 population. Imported dengue fever cases were reported in all months, with the peak reported from May to November (374 cases, 89.69%). Local cases were first reported in May and the last in December, with the highest incidence from August to November (2 960 cases, 95.45%). The cases were reported in all 11 administrative districts; the top three were Baiyun District, Yuexiu District, and Liwan District. Male and female cases accounted for 53.52% and 46.48%, respectively; the age group mainly concentrated between 20-<60 years (2 547 cases, 72.40%). The top three occupations were business services (784 cases), housework and unemployment (738 cases), and retirees (596 cases). The average time from onset to diagnosis for local cases was 4.06 days, and 4.60 days for imported cases. The overseas imported cases mainly came from Southeast Asia 88.10%(311/353), with the most being imported from Cambodia. Cases imported from other provinces mainly came from Yunnan Province, and cases imported from other cities within the province mainly came from Foshan City. Conclusions In recent years, the incidence of dengue fever in Guangzhou has remained at a high level, with obvious imported and seasonal characteristics. Relevant departments should pay attention to key populations and take effective measures to reduce the density of mosquito vectors, and strictly prevent the spread of dengue fever. [ABSTRACT FROM AUTHOR]

Objective To analyze the epidemiological characteristics of a local outbreak of dengue fever caused by a construction site in Shenzhen City, evaluate the effectiveness of control measures, and explore dengue fever prevention and control strategies suitable for local characteristics. Methods Epidemiological investigations were conducted on dengue fever cases during the outbreak. Descriptive analysis methods were used to analyze the epidemiological characteristics of the outbreak. The Breteau Index method and double-layer trap method were employed to monitor mosquito density and evaluate the effectiveness of control measures. Results A total of 85 cases were reported in this outbreak, all of which were local cases. Among them, 76 cases (89.41%) were laboratory-confirmed, and 9 cases (10.59%) were clinically diagnosed. All laboratory-confirmed cases were identified as Dengue Virus Serotype 1 (DENV-1). There were 64 male and 21 female cases, with no critical or fatal cases. The age of cases ranged from 4 to 78 years old, with the highest number of cases occurring in the 31-<50 age group (43 cases, 50.59%). The majority of cases were construction workers (38 cases, 44.71%). The outbreak was mainly concentrated in Qiutou Community, Fu Hai Street, Bao'an District, accounting for 69 cases (81.18%). The median and quartile M (P25, P75) interval between onset of illness and diagnosis was 3 (2, 5) days, with construction workers having a shorter interval between onset and seeking medical attention compared to other residents. After implementing control measures such as case search, isolation and treatment, mosquito control, cleaning of mosquito breeding sites, and health education, the daily average Breteau Index decreased from the initial 12 to below 3, and the adult mosquito density remained at 0 mosquitoes (person/hour). Conclusions This outbreak was a local dengue fever outbreak initiated at a construction site. After the community staff participated in the comprehensive prevention and control measures, including case searching, mosquito elimination, clearing of breeding grounds, environmental health inspection, and education and propaganda, the epidemic was effectively contained. In addition, the continuous improvement of clinicians' diagnostic levels for dengue fever and the popularization of dengue fever antigen primary screening reagents (NS1 antigen reagents) in medical institutions may have played a crucial role in the early detection of the epidemic. [ABSTRACT FROM AUTHOR]

Background: Analyses of the temporal distribution of mosquitoes are presented in statistical charts, but it is difficult to prove in statistics whether differences in peak periods exist among different years or habitats. This study aimed to investigate the application of circular statistics in determining the peak period and a comparison of differences. Methods: Surveillance of adult mosquitoes was conducted twice a month by light traps in five different habitats from March to November for 3 years (2021–2023) in Qingdao, Shandong Province, China. The Kruskal–Wallis test was performed to determine the differences in mosquito density among different years and habitats. Circular statistics and line charts were employed to determine the peak period and a comparison of differences. Results: Among a total of 14,834 adult mosquitoes comprising five mosquito species from four genera, Culex pipiens pallens was dominant and accounted for 89.6% of the specimens identified. Aedes albopictus, Armigeres subalbatus, and Anopheles sinensis made up 5.7%, 4.2%, and 0.5%, respectively. Culex tritaeniorhynchus accounted for less than 0.1%. The mean mosquito density (females/trap night) for the trapping period was 10.3 in 2021, 5.6 in 2022, and 3.6 in 2023. Among five habitats, the highest mosquito density was 8.9 in livestock sheds, followed by 6.8 in parks, 5.9 in rural dwellings, 5.5 in urban dwellings, and 5.4 in hospitals. No statistically significant differences were found among different years (H = 1.96, d.f. 2, P = 0.376) and habitats (H = 0.45, d.f. 4, P = 0.978). Overall, the peak period of mosquito activity fell in the months from June to September. The peak period among 3 years differed significantly (F(2,7022) = 119.17, P < 0.01), but there were no statistically significant differences in peak period among different habitats (F(4,7020) = −159.09, P > 0.05). Conclusion: Circular statistics could be effectively combined with statistical charts to elucidate the peak period of mosquitoes and determine the differences in statistics among different years and habitats. These findings will provide valuable information for mosquito control and public health management. [ABSTRACT FROM AUTHOR]

Background: Dengue is an increasing health burden that has spread throughout the tropics and sub-tropics. There is currently no effective vaccine and control is only possible through integrated vector management. Early warning systems (EWS) to alert potential dengue outbreaks are currently being explored but despite showing promise are yet to come to fruition. This study addresses the association of meteorological variables with both mosquito indices and dengue incidences and assesses the added value of additionally using mosquito indices for predicting dengue incidences. Methodology/Principal findings: Entomological surveys were carried out monthly for 14 months in six sites spread across three environmentally different cities of the Philippines. Meteorological and dengue data were acquired. Non-linear generalized additive models were fitted to test associations of the meteorological variables with both mosquito indices and dengue cases. Rain and the diurnal temperature range (DTR) contributed most to explaining the variation in both mosquito indices and number of dengue cases. DTR and minimum temperature also explained variation in dengue cases occurring one and two months later and may offer potentially useful variables for an EWS. The number of adult mosquitoes did associate with the number of dengue cases, but contributed no additional value to meteorological variables for explaining variation in dengue cases. Conclusions/Significance: The use of meteorological variables to predict future risk of dengue holds promise. The lack of added value of using mosquito indices confirms several previous studies and given the onerous nature of obtaining such information, more effort should be placed on improving meteorological information at a finer scale to evaluate efficacy in early warning of dengue outbreaks. Author summary: Dengue is a widespread mosquito-borne disease. Mosquitoes are sensitive to temperature and rainfall and hence there have been efforts to identify such variables for predicting dengue outbreaks. Several mosquito indices are measured routinely by national surveillance systems, but which vary considerably in their success of predicting dengue outbreaks. This study explored the current and lagged associations of meteorological variables with mosquito indices and dengue incidence. Associations of mosquito indices with dengue were also explored. Rain and the diurnal temperature range (DTR) contributed most to explaining the variation in both mosquito indices and number of dengue cases. DTR and minimum temperature also explained variation in dengue cases occurring one and two months later. Mosquito indices did not provide any additional explanatory power for dengue incidences. Given the onerous nature of measuring mosquito indices, advanced warning systems might be improved using meteorological variables measured at finer scales than that traditionally available. [ABSTRACT FROM AUTHOR]

Lymphatic filariasis (LF) is a crippling and disfiguring parasitic condition. India accounts for 55% of the world's LF burden. The filarial parasite Wuchereria bancrofti is known to cause 99.4% of the cases while, Brugia malayi accounts for 0.6% of the issue occurring mainly in some pockets of Odisha and Kerala states. The Balasore (Baleswar) district of Odisha has been a known focus of B. malayi transmission. We employed molecular xenomonitoring to detect filarial parasite DNA in vectors. In six selected villages, Gravid traps were used to collect Culex mosquitoes and hand catch method using aspirators was followed for collection of mansonioides. A total of 2903 mosquitoes comprising of Cx. quinquefasciatus (n = 2611; 89.94%), Cx. tritaeniorhynchus (n = 100; 3.44%), Mansonia annuliferea (n = 139; 4.78%) and Mansonia uniformis (n = 53; 1.82%) were collected from six endemic villages. The species wise mosquitoes were made into 118 pools, each with a maximum of 25 mosquitoes, dried and transported to the laboratory at VCRC, Puducherry. The mosquito pools were subjected to parasite DNA extraction, followed by Real-time PCR using LDR and HhaI probes to detect W. bancrofti and B. malayi infections, respectively. Seven pools (6.66%) of Cx. quinquefasciatus, showed infection with only W. bancrofti while none of the pools of other mosquito species showed infection with either W. bancrofti or B. malayi. Although the study area is endemic to B. malayi, none of the vectors of B. malayi was found with parasite infection. This study highlights the ongoing transmission of bancroftian filariasis in the study villages of Balasore district of Odisha and its implications for evaluating LF elimination programme. [ABSTRACT FROM AUTHOR]

Background: Reports showed that Amhara Region is accounting for 31% of Ethiopia's malaria burden. Reports also depicted that despite the existing malaria vector control tools implemented by the regional government, currently there is an increment in malaria prevalence in the region. This might be due to lack of entomological monitoring and comprehensive information on the prevailing species composition, infection rate and feeding presences of An. mosquito species in the study areas. Therefore, this study aimed to address this information. Methods: A community-based cross-sectional study was conducted from 18 February to 30 March 2023 at three districts of the west Amhara Region. For this, six CDC light traps (three indoor and three outdoor) were used to collect adult female An. mosquito species. In this study, 261 An. mosquito species comprising seven species were collected. Their morphological identification and abdominal status determination were carried out using standard morphological identification keys under a dissection microscope. While their infection rates and blood meal sources were determined, using circumsporozoite protein-ELISA and blood meal-ELISA based on the standard protocol. Data were entered to SPSS versions 20 for analysis and p- value < 0.05 was considered as statistically significant. Results: In our study, total of 261 An. mosquito species were identified. An. demeilloni was the most abundant species accounted for 112(42.9%) of all captures. It was also the most predominant species at Ayehu-Guagusa followed by Jabitehnan districts. An. demeilloni and An. cinereus altogether accounting for infection rate of 3(1.1%) for P. vivax parasite. Furthermore, our study showed that more than 50% of An. mosquito species collected fed on cattle blood showing shifting of feeding behaviors. Conclusions: Our study depicted that An. demeilloni and An. cinereus were the most abundant species and infected with P. vivax parasite. Therefore, further comprehensive study should be done in the future. [ABSTRACT FROM AUTHOR]