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Worldwide, mosquitoes are of great medical and economic importance due to their profound negative impact on humans. Mosquitoes act as both nuisance pests and disease vectors that account for millions of cases of illness and death annually. They rely on complex olfactory systems for many of their fundamental processes such as finding mates, identifying egg-laying sites, and directly linked to their disease vectoring capabilities, locating blood-meals. Their olfactory systems rely on three major categories of receptors: odorant receptors, ionotropic receptors, and gustatory receptors. These receptors, along with sensors of various environmental cues such as CO2, heat, and humidity, contribute to the mosquito’s chemosensory responses. The yellow fever mosquito, Aedes aegypti, is responsible for the transmission of key diseases such as dengue virus, yellow fever virus, chikungunya virus, and Zika virus. Because of its profound impacts on human health, there is growing interest in exploring new ways to disrupt Ae. aegypti’s olfactory-based behaviours as a means of reducing disease transmission. While there are numerous studies focused on adult mosquito chemoreception, little is known about these processes in mosquito larvae. Here, a chemotaxis response assay was developed to examine which naturally occurring chemicals would attract Ae. aegypti larvae. Mosquito larvae were subsequently fed E. coli bacteria expressing double stranded RNA targeting a larval specific odorant receptor, OR34. RNA interference knockdown of the gene’s transcript was confirmed via qRT-PCR, and chemotaxis assays were used to identify putative odorant ligands to this receptor. This research describes a simple chemotaxis response assay that can be used to identify larval mosquito attractants and an effective way to identify odorant receptors’ potential ligands. Using this information, it should be possible to screen for other ligands that may be used to disrupt mosquito olfaction, and thus develop n

Komarci (Diptera: Culicidae) su prepoznati kao globalni problem po zdravlje ljudi i životinja, ekonomiju i održivi razvoj. Komarci ometaju ljudsku delatnost što može negativno uticati na kvalitet života. U Srbiji postoji veliki diverzitet autohtonih vrsta komaraca kojima za razvoj pogoduje umerena klima i obilje vodenih staništa, ali i neadekvatno održavane vodene površine kako u ruralnim tako i u urbanim sredinama. Invazivne vrste kao što je azijski tigrasti komarac, Aedes albopictus Skuse, 1895, ali i autohtona vrsta Culex pipiens Linneaus, 1758 uspešno se razmnožavaju čak i u posudama malih dimenzija u kojima se akumuliše voda. Imajući u vidu biologiju ovih vrsta mnogi prirodni i veštački recipijenti vode u urbanim sredinama predstavljaju potencijalna razvojna staništa ovih vrsta što značajno otežava njihovo suzbijanje. Srbija je danas endemsko područje za zoonotske flaviviruse, pre svega virus Zapadnog Nila (West Nile virus – WNV) i Usutu virus čiji su glavni (ali ne i jedini prenosioci) u Evropi komarci vrste Cx. pipiens. Prilikom procene rizika za širenje uzročnika bolesti bitno je identifikovati prisutne vrste komaraca na datom području, a potom i njihove biotipove. Dobro poznavanje biologije komaraca je osnova za procenu rizika i za donošenje odluka o njihovom suzbijanju. Za procenu rizika posebno su značajne determinante kapaciteta vektora i to brojnost populacije komaraca i njihova vektorska kompetentnost. Eksperimentalno je potvrđeno da Ae. albopictus prenosi WNV. Bez obzira na manju efikasnost transmisije u odnosu na Cx. pipiens, njihova velika brojnost daje doprinos u širenju WNV. Uspešno dugogodišnje širenje areala rasprostiranja azijskog tigrastog komarca u Srbiji kao i adaptiranost na umereni klimat u kome ova vrsta prezimljava, otežava kontrolu pojave i širenja WNV. Korišćenjem naučnog pristupa u kontroli vektora i primenom savremenih metoda kao odgovor na precizno identifikovan problem u sredini gde se vrši suzbijanje komaraca, racionalizuje se pot, Mosquitoes (Diptera: Culicidae) are recognized as a global problem for human and animal health, the economy, and sustainable development. Mosquitoes disrupt human activities, which can significantly negatively impact quality of life and economy. Serbia has a large diversity of indigenous mosquito species that thrive in a moderate climate and abundant water habitats, as well as inadequately maintained water surfaces in both rural and urban areas. Invasive species such as the Asian tiger mosquito, Aedes albopictus (Skuse, 1895), as well as the indigenous species Culex pipiens (Linnaeus, 1758), successfully breed even in small containers where water accumulates. Considering the biology of these species, many natural and artificial water recipients in urban areas represent potential developmental habitats for these species, significantly complicating their control. Serbia is now an endemic area for zoonotic flaviviruses, primarily the West Nile virus (WNV) and Usutu virus, whose main (but not only) vectors in Europe are mosquitoes of the species Culex pipiens. When assessing the risk of disease spread, it is essential to identify the present mosquito species in a given area, and then their biotypes. A good understanding of mosquito biology is the basis for risk assessment and decision-making regarding their control. Determinants of vector capacity, such as mosquito population abundance and vector competence, are particularly important in risk assessment. It has been experimentally confirmed that Ae. albopictus transmits WNV. Despite its lower transmission efficiency compared to Cx. pipiens, their high abundance contributes to the spread of WNV. The expansion of areas where the Asian tiger mosquito is present in Serbia in a stable population that overwinters is significant for controlling the occurrence and spread of WNV. By using a scientific approach to vector control and implementing modern methods in response to precisely identified problems in environments where mos

Background: House screening remains conspicuously absent in national malaria programs despite its recognition by the World Health Organization as a supplementary malaria vector-control intervention. This may be attributed, in part, to the knowledge gap in screen durability or longevity in local climatic conditions and community acceptance under specific cultural practices and socio-economic contexts. The objectives of this study were to assess the durability of window and door wire mesh screens a year after full house screening and to assess the acceptability of the house screening intervention to the participants involved. Methods: This study was conducted in Nyimba district, Zambia and used both quantitative and qualitative methods of data collection and analysis. Both direct observation and questionnaires were employed to assess the durability of the screens and the main reasons for damage. Findings on damage were summarized as percentages. Focus group discussions were used to assess people’s knowledge, perceptions, and acceptability of the closing eaves and house screening intervention. Deductive coding and inductive coding were used to analyse the qualitative data. Results: A total of 321 out of 400 (80.3%) household owners of screened houses were interviewed. Many window screens (90.3%) were intact. In sharp contrast, most door screens were torn (n = 150; 46.7%) or entirely removed (n = 55; 17.1%). Most doors (n = 114; 76%) had their wire mesh damaged or removed on the bottom half. Goats (25.4%), rust (17.6%) and children (17.1%) were cited most as the cause of damage to door screens. The focus group discussion elicited positive experiences from the participants following the closing of eaves and screening of their windows and doors, ranging from sleeping peacefully due to reduced mosquito biting and/or nuisance and having fewer insects in the house. Participants linked house screening to reduced malaria in their households and community. Conclusion: This stud

Mosquitoes are significant disease vectors, spreading pathogens that cause diseases like malaria, dengue, and Zika worldwide. In Australia, local mosquito species play a crucial role in disease transmission. Effective control strategies must consider the ecological characteristics of the target species and the surrounding environment. The first part of this thesis focused on studying the population structure and dispersal patterns of the Australian Backyard mosquito (Aedes notoscriptus) at fine and global scales. Notably, this species displays higher dispersal capabilities compared to the primary dengue-transmitting mosquito, Ae. aegypti. By combining mitochondrial DNA (mtDNA) and genome-wide single nucleotide polymorphisms (SNPs), I found evidence for cryptic mtDNA lineages of Ae. notoscriptus with varying geographical distributions. Additionally, SNP analysis identifies six distinct genomic groups that do not consistently align with the mtDNA lineages. The discordance between mtDNA and nuclear DNA is not attributed to Wolbachia infections but may be influenced by factors such as sex-specific asymmetries and human-assisted displacement. Furthermore, insights into invasive Ae. notoscriptus populations in New Zealand and the USA suggest their likely origin in Victoria, Australia. Additionally, I tested a novel mosquito trap design by evaluating its effectiveness through field and laboratory studies. The findings indicate that this system effectively reduces the number of Ae. notoscriptus eggs in the field. Furthermore, by reviewing existing literature, conducting human-baited field trials, and performing laboratory experiments, I found that the levels of male mosquito attraction to humans seems to be highly species specific, which is important for the effective and sustainable management of male mosquito releases to control population sizes and disease transmission.

Vector-borne disease is an important facet of public health, as they account for nearly 20% of global disease burden. Multiple species, including at least one vector, at least one host, and a pathogen, must interact in vector-borne disease transmission cycles, and thus understanding human risk of vector-borne disease and public health outcomes requires a community ecology framework. Members of the Culex genus, including Cx. pipiens, Cx. quinquefasciatus, and Cx. restuans are sympatric in eastern North America and are vectors of West Nile virus. This dissertation explores the roles of habitat use, community ecology, phenology, and landscape heterogeneity on Culex spatiotemporal dynamics and genetics along urban to rural gradients in eastern North America. Through surveillance of belowground structures in Washington, D.C. over two years, I found that mosquito species of public health importance, including Aedes aegypti, Aedes albopictus, and members of the Culex pipiens assemblage, use these structures for breeding and development. Belowground structures may serve as refugia against extreme climatic conditions and facilitate overwintering survival for non-diapausing taxa and/or taxa with thermal tolerance limitations, potentially expanding their suitable ranges. On an urban to rural gradient in greater Washington, D.C. and Maryland, a complex of cryptic Culex WNv vectors co-occur on the landscape. Using molecular techniques and constrained ordination, I found that these cryptic Culex species were differently distributed at fine spatial scales, likely due to the impacts of urbanization on vector habitat and subsequent niche segregation. Culex pipiens were cosmopolitan and dominant across sites in greater Washington D.C. and Maryland. However, individuals with Cx. quinquefasciatus ancestry were limited to urban and peri-urban sites closest to the city center, and Cx. restuans were most abundant in rural and suburban sites furthest from the city center with dense and het

The Aedes (stegomyia) aegypti (Linnaeus, 1762) mosquito, the main vector of dengue, Zika and chikungunya viruses, is accli-mated to urban areas and its distribution continues to increase. One of the tools for its control is the use of insecticides; how-ever, some populations have become resistant to these pro-ducts. Resistance is an adaptation of the mosquito that allows it to cope with the pressure imposed by insecticides. Neverthe-less, it can also have ecological costs by affecting other charac-teristics and inducing slow development, reduced longevity, decreased egg production and hatching. It can also affect the pathogen-insect interaction, leading to a possible major nega-tive impact on human health., El mosquito Aedes (stegomyia) aegypti (Linnaeus, 1762), principal vector de los virus del dengue, Zika y chikungunya, está aclima-tado a zonas urbanas y su distribución sigue en aumento. Una de las herramientas para su control es el uso de insecticidas; sin embargo, algunas poblaciones se han vuelto resistentes a esos productos. La resistencia es una adaptación del mosqui-to que le permite lidiar con la presión impuesta por los insecti-cidas. No obstante, también puede tener costos ecológicos, al afectar otras características e inducir un lento desarrollo, reduc-ción en la longevidad, disminución en la producción y eclosión de huevos. También puede afectar la interacción patógeno-in-secto, lo que ocasiona un posible impacto negativo mayor en la salud humana.

Poslednjih nekoliko godina je u Srbiji konstanto prisutna cirkulacija virusa Zapadnog Nila (VZN). U humanoj populacije su zabeležene veće ili manje epidemije počev od 2012. godine pa sve do danas. Veterinarska služba u Srbiji je od juna 2022. godine pokrenula godišnji nacionalni program monitoringa VZN, koji je predstavljao nastavak godišnjih programa monitoringa počev od 2014. godine. Program je finansiran od strane Uprave za veterinu, a na terenu ga je sprovodila veterinarska služba u saradnji sa entomolozima i ornitolozima. Cilj programa je bila rana detekcija prisustva VZN na nekom području i pravovremeno alarmiranje humane zdravstvene službe i lokalnih samouprava radi sprovođenja mera kontrole (suzbijanja komaraca) i informisanja stanovništva. Program monitoringa se zasnivao na indirektnom i direktnom praćenju prisustva VZN u prirodi. Indirektno praćenje virusa se vršilo serološkim testiranjem konja na prisustvo IgM antitela i sentinel teladi uzrasta 6 do 8 meseci (oteljenih nakon sezone vektora u prethodnoj godini) na IgG antitela protiv VZN kao potvrda akutne infekcije i cirkulacije VZN. Direktno praćenje se vršilo ispitivanjima zbirnih uzoraka komaraca i uzoraka divljih ptica na prisustvo VZN molekularnim dijagnostičkim metodama u aktivnom i uzoraka na bolest suspektnih konja u pasivnom nadzoru. Broj uzoraka za ispitivanje je određen po okruzima na osnovu visine rizika od pojave infekcije VZN. U periodu jun-septembar 2022. na području R. Srbije je po programu ispitano 1853 krvnih seruma konja od čega je kod 25 (1,30%) utvrđeno prisustvo IgM antitela. Ista je bila u uzlaznoj liniji sa povećanjem aktivnosti vektora i u junu je kod 0,9% (4/437), u julu kod 2,0% (10/490), u avgustu kod 1,9% (9/468) i u septembru kod 0,9% (4/458) konja utvrđen pozitivan serološki odgovor. Broj okruga u kojima je detektovana serokonverzija je iznosio 2 u junu, 3 u julu, 5 u avgustu i 3 u septembru. U istom periodu je na području visoko rizičnih okruga (14/25) kod 1740 ispitanih te, The constant circulation of West Nile virus (WNV) has been detected in the last few years in Serbia. Bigger or smaller epidemics have been reported in human population in Serbia since 2012, until today. The veterinary service in Serbia launched the yearly national program for WNV monitoring in June 2022, and it was a continuation of the yearly monitoring programs conducted since 2014. The program was funded by the Veterinary Directorate, and it is implemented on the field by veterinary service in collaboration with entomologists and ornithologists. The main objective of the monitoring program was the early detection of the presence of WNV in a certain area, and timely alerting of human health services and local governments in order to control the mosquito population and to inform the local communities. The monitoring program was based on the direct and indirect monitoring of the presence of WNV in the environment. Indirect monitoring of virus presence was performed by serological testing of horses on the presence of anti-WNV IgM antibodies, and sentinel calves aged 6 to 8 months (calved after the vector season in the previous year) for the presence of anti-WNV IgG antibodies, as the confirmation of acute infection. Direct monitoring of the WNV presence in nature was done by molecular testing of WNV presence in pooled mosquito’s samples and in wild birds in active surveillance and by testing the samples of clinically suspected horses in passive surveillance. The number of tested samples was defined at the level of each district of the Republic of Serbia in relation to the risks of WNV infection. In the period of June-September 2022 in Serbia, according to the program, 1853 blood sera of horses were tested, and seroconversion (IgM antibodies) was detected in 25 (1.3%) horses. The seroconversion was in an upward line in concordance with the increase in the activity of the vectors, thus positive serological responses were determined in June in 0.9% (4/437), in July in 2

Background Phylogenetic analyses of closely related species of mosquitoes are important for better understanding the evolution of traits contributing to transmission of vector-borne diseases. Six out of 41 dominant malaria vectors of the genus Anopheles in the world belong to the Maculipennis Group, which is subdivided into two Nearctic subgroups (Freeborni and Quadrimaculatus) and one Palearctic (Maculipennis) subgroup. Although previous studies considered the Nearctic subgroups as ancestral, details about their relationship with the Palearctic subgroup, and their migration times and routes from North America to Eurasia remain controversial. The Palearctic species An. beklemishevi is currently included in the Nearctic Quadrimaculatus subgroup adding to the uncertainties in mosquito systematics. Results To reconstruct historic relationships in the Maculipennis Group, we conducted a phylogenomic analysis of 11 Palearctic and 2 Nearctic species based on sequences of 1271 orthologous genes. The analysis indicated that the Palearctic species An. beklemishevi clusters together with other Eurasian species and represents a basal lineage among them. Also, An. beklemishevi is related more closely to An. freeborni, which inhabits the Western United States, rather than to An. quadrimaculatus, a species from the Eastern United States. The time-calibrated tree suggests a migration of mosquitoes in the Maculipennis Group from North America to Eurasia about 20–25 million years ago through the Bering Land Bridge. A Hybridcheck analysis demonstrated highly significant signatures of introgression events between allopatric species An. labranchiae and An. beklemishevi. The analysis also identified ancestral introgression events between An. sacharovi and its Nearctic relative An. freeborni despite their current geographic isolation. The reconstructed phylogeny suggests that vector competence and the ability to enter complete diapause during winter evolved independently in different line

The worldwide spread of the Asian Tiger Mosquito (ATM), Aedes albopictus, demands effective and sustainable urban mosquito management, due to their disease vector capacity and potential for causing high nuisance levels. Agency-led mosquito management is often ineffective at controlling ATM or unwanted by residents. In 2016 and 2017, citizens of University Park, Maryland, USA led a town-wide campaign to encourage residents to purchase Gravid Aedes Traps (GATs), a lethal oviposition trap successful at capturing Aedes mosquitoes. This campaign resulted in significant reductions of adult female ATM in areas with >80% GAT coverage among yards. The goal of this study was to test the continued effectiveness of University Park’s citizen-led program and explore social and environmental predictors of household GAT deployment in 2021. We conducted adult trapping at 18 sites in University Park to test if current levels of GAT deployment still predicted reductions in area-wide adult female ATM, distributed an online questionnaire to gather data for testing relationships of demographic, environmental, knowledge, and attitude predictors with household GAT deployment, and conducted environmental yard surveys to assess relationships of GAT deployment with container habitat and mosquito container infestation. We found that only 24.9% (130/523) of University Park households deployed GATs in 2021, which is substantially lower than the 46.0% (439/954) of households that deployed GATs in 2017. GAT coverage in 2021 did not exceed 50% (3/6) in any adult-trapping area, well below the 80% threshold thought needed to reduce area wide adult Aedes. Nevertheless, we found a significant negative relationship between household GAT deployment and adult female ATM, indicating that GATs are still effective at controlling Aedes at lower coverages. Households that deployed GATs had lower numbers of total, but not infested, water-filled containers, suggesting GAT deployment was often a part of a househo

This study has adopted a qualitative systematic review design to analyze the reason behind the revelation of Qur’an, 2:26 and its implications according to the signs in modern medicine. The relevant tafsir of the Qur’anic verses were collected from famous tafsir of the Qur’an. Data concerning modern medicine were collected from the published articles screened from MEDLINE and PUBMED databases. Data were then analyzed by Thematic analysis to show what Allah (S.W.T) has shown the medical experts with regard to what He has revealed in this verse. The results show that the phrase ????? ????????? used in the phrase ????? ??????? ??? ??????????? ??? ???????? ??????? ???? ????????? of this verse exposes that Allah (S.W.T) has dispersed small creatures [such as parasites and microbes] ‘on top’ of the mosquitoes’ bodies. This study may provide us with a glimpse of the wonders of the Qur’an and the Majesty of Allah (S.W.T).

CRISPR/Cas9 technologies are important tools for the development of gene-drive systems to modify mosquito vector populations to control the transmission of pathogens that cause diseases such as malaria. However, one of the challenges for current Cas9-based drive systems is their ability to produce drive-resistant alleles resulting from insertions and deletions (indels) caused principally by nonhomologous end-joining following chromosome cleavage. Rapid increases in the frequency of such alleles may impair gene-drive dynamics. We explored the generation of indels in the germline and somatic cells in female gene-drive lineages using a series of selective crosses between a gene-drive line, AgNosCd-1, and wild-type mosquitoes. We find that potential drive-resistant mutant alleles are generated largely during embryonic development, most likely caused by deposition of the Cas9 endonuclease and guide RNAs in oocytes and resulting embryos by homozygous and hemizygous gene-drive mothers.

Hemocytes, similar to vertebrate blood cells, play important roles in insect development and immunity, but it is not well understood how they perform their tasks. New technology, in particular single-cell transcriptomic analysis in combination with Drosophila genetics, may now change this picture. This review aims to make sense of recently published data, focusing on Drosophila melanogaster and comparing to data from other drosophilids, the malaria mosquito, Anopheles gambiae, and the silkworm, Bombyx mori. Basically, the new data support the presence of a few major classes of hemocytes: (1) a highly heterogenous and plastic class of professional phagocytes with many functions, called plasmatocytes in Drosophila and granular cells in other insects. (2) A conserved class of cells that control melanin deposition around parasites and wounds, called crystal cells in D. melanogaster, and oenocytoids in other insects. (3) A new class of cells, the primocytes, so far only identified in D. melanogaster. They are related to cells of the so-called posterior signaling center of the larval hematopoietic organ, which controls the hematopoiesis of other hemocytes. (4) Different kinds of specialized cells, like the lamellocytes in D. melanogaster, for the encapsulation of parasites. These cells undergo rapid evolution, and the homology relationships between such cells in different insects are uncertain. Lists of genes expressed in the different hemocyte classes now provide a solid ground for further investigation of function.

Mosquito-borne diseases (MBDs), including those caused by flaviviruses, remain human health problems for developing and urbanizing economies. This cross-sectional study examined risks of flavivirus exposure through a survey regarding knowledge and practices of pig farmers, and serological analysis of pigs in peri-urban and suburban Hanoi city. A total of 636 pig sera from 179 pig farms in 4 districts, namely, Chuong My, Dan Phuong, Ha Dong, and Bac Tu Liem, were analyzed by a competitive ELISA designed for flavivirus antibody detection. The results indicated a low level of awareness about MBDs among pig farmers, and a high seroprevalence in pigs at 88.5% (95%CI = 85.8-90.9%). Moreover, common practices of pig owners to prevent mosquitoes at home and farm did not show a significant reduction in flavivirus exposure in pigs. At animal level, significant associations between seropositive pigs and the farms with more than 60 pigs, and the district location were found. Farm-level multivariable analysis did not identify significant risk factors for flavivirus exposure. The study suggests that improving awareness of pig owners about MBDs in Hanoi city may be warranted to reduce the risk for MBD flavivirus infections in both humans and pigs.

Mosquito species belonging to the genus Aedes have attracted the interest of scientists and public health officers because of their capacity to transmit viruses that affect humans. Some of these species were brought outside their native range by means of trade and tourism and then colonised new regions thanks to a unique combination of eco-physiological traits. Considering mosquito physiological and behavioural traits to understand and predict their population dynamics is thus a crucial step in developing strategies to mitigate the local densities of invasive Aedes populations. Here, we synthesised the life cycle of four invasive Aedes species (Ae. aegypti, Ae. albopictus, Ae. japonicus and Ae. koreicus) in a single multi-scale stochastic modelling framework which we coded in the R package dynamAedes. We designed a stage-based and time-discrete stochastic model driven by temperature, photo-period and inter-specific larval competition that can be applied to three different spatial scales: punctual, local and regional. These spatial scales consider different degrees of spatial complexity and data availability by accounting for both active and passive dispersal of mosquito species as well as for the heterogeneity of the input temperature data. Our overarching aim was to provide a flexible, open-source and user-friendly tool rooted in the most updated knowledge on the species' biology which could be applied to the management of invasive Aedes populations as well as to more theoretical ecological inquiries.

Microbial communities are known to influence mosquito lifestyles by modifying essential metabolic and behavioral processes that affect reproduction, development, immunity, digestion, egg survival, and the ability to transmit pathogens. Many studies have used 16S rRNA gene amplicons to characterize mosquito microbiota and investigate factors that influence host-microbiota dynamics. However, a relatively low taxonomic resolution due to clustering methods based on arbitrary threshold and the overall dominance of Wolbachia or Asaia symbionts obscured the investigation of rare members of mosquito microbiota in previous studies. Here, we used high resolution Shannon entropy-based oligotyping approach to analyze the microbiota of Culex pipiens, Culex quinquefasciatus and Aedes individuals from continental Southern France and overseas Guadeloupe as well as from laboratories with or without antibiotics treatment. Our experimental design that resulted in a series of mosquito samples with a gradient of Wolbachia density and relative abundance along with high-resolution analyses of amplicon sequences enabled the recovery of a robust signal from typically less accessible bacterial taxa. Our data confirm species-specific mosquito-bacteria associations with geography as a primary factor that influences bacterial community structure. But interestingly, they also reveal co-occurring symbiotic bacterial variants within single individuals for both Elizabethkingia and Erwinia genera, distinct and specific Asaia and Chryseobacterium in continental and overseas territories, and a putative rare Wolbachia variant. Overall, our study reveals the presence of previously overlooked microdiversity and multiple closely related symbiotic strains within mosquito individuals with a remarkable habitat-specificity.

Reports of West Nile virus (WNV) associated disease in humans were scarce in Spain until summer 2020, when 77 cases were reported, eight fatal. Most cases occurred next to the Guadalquivir River in the Sevillian villages of Puebla del Río and Coria del Río. Detection of WNV disease in humans was preceded by a large increase in the abundance of Culex perexiguus in the neighbourhood of the villages where most human cases occurred. The first WNV infected mosquitoes were captured approximately one month before the detection of the first human cases. Overall, 33 positive pools of Cx. perexiguus and one pool of Culex pipiens were found. Serology of wild birds confirmed WNV circulation inside the affected villages, that transmission to humans also occurred in urban settings and suggests that virus circulation was geographically more widespread than disease cases in humans or horses may indicate. A high prevalence of antibodies was detected in blackbirds (Turdus merula) suggesting that this species played an important role in the amplification of WNV in urban areas. Culex perexiguus was the main vector of WNV among birds in natural and agricultural areas, while its role in urban areas needs to be investigated in more detail. Culex pipiens may have played some role as bridge vector of WNV between birds and humans once the enzootic transmission cycle driven by Cx. perexiguus occurred inside the villages. Surveillance of virus in mosquitoes has the potential to detect WNV well in advance of the first human cases.

Despite their past importance as vectors of indigenous malaria, the species composition and spatial distribution of the members of the Anopheles maculipennis complex have been studied to a limited extent in the Netherlands. Therefore, this investigation focuses on the distribution of the members of this complex in the Netherlands, including Anopheles daciae, which has recently been found in countries bordering the Netherlands. In the framework of a national mosquito surveillance between 2010 and 2021, a total of 541 specimens of An. maculipennis s.l. were analyzed from 161 locations covering the entire territory. In addition, 89 specimens were analyzed from overwintering sites during the winter of 2020/2021. All individual mosquitoes were identified to species-level using Sanger sequencing of the ribosomal internal transcribed spacer 2. To characterize the habitat of An. maculipennis s.l. in the Netherlands, land cover use data was extracted in a 1 km buffer area around each finding location. For populations collected in summers between 2010 and 2021, the most frequent species was An. messeae, present in 88.19% of the locations, followed by An. maculipennis s.s. (11.80%), An. atroparvus (3.72%) and An. daciae (3.72%). Anopheles daciae was found in the southern inland areas of the country. Furthermore, An. messeae and An. daciae occurred in sympatry at overwintering sites. This study provides relevant information on the occurrence of species of the Anopheles maculipennis complex in the Netherlands, contributing to a better estimation of the risk of mosquito-borne disease in the country.

Mosquitoes are among the deadliest creatures in the world due to their propensity for spreading pathogens to humans. Surveillance is an important step in controlling and monitoring mosquito populations. The most common technique used for mosquito surveillance requires a highly trained entomologist to identify and determine information such as sex, gonotrophic stage, infection status of the mosquitoes morphologically by means of dissection. Identification using this method is time-consuming and requires skills that only highly trained entomologists possess, which limit the sample size of tested mosquitoes. A new method using Fourier transform infrared (FT-IR) microspectroscopy eliminates these restrictions by streamlining mosquito sample processing and lowering the skill required to perform the method. The method outlined in this study can be completed more quickly and by technicians of varied skill levels. Samples of parous and nulliparous Aedes triseriatus (170 samples) identified by a trained entomologist were used to test the method’s ability to discriminate parity. Mid-infrared spectra of the mosquitoes were collected, preprocessed, and partial least squares discriminant analysis (PLS-DA) was used to discriminate between the parous and nulliparous mosquitoes. The method identified the parity status of the mosquitoes with 100% accuracy, 100% true positive rate (TPR), and 100% true negative rate(TNR).

Mosquito species belonging to the genus Aedes have attracted the interest of scientists and public health officers because of their capacity to transmit viruses that affect humans. Some of these species were brought outside their native range by means of trade and tourism and then colonised new regions thanks to a unique combination of eco-physiological traits. Considering mosquito physiological and behavioural traits to understand and predict their population dynamics is thus a crucial step in developing strategies to mitigate the local densities of invasive Aedes populations. Here, we synthesised the life cycle of four invasive Aedes species (Ae. aegypti, Ae. albopictus, Ae. japonicus and Ae. koreicus) in a single multi-scale stochastic modelling framework which we coded in the R package dynamAedes. We designed a stage-based and time-discrete stochastic model driven by temperature, photo-period and inter-specific larval competition that can be applied to three different spatial scales: punctual, local and regional. These spatial scales consider different degrees of spatial complexity and data availability by accounting for both active and passive dispersal of mosquito species as well as for the heterogeneity of the input temperature data. Our overarching aim was to provide a flexible, open-source and user-friendly tool rooted in the most updated knowledge on the species’ biology which could be applied to the management of invasive Aedes populations as well as to more theoretical ecological inquiries. Graphical Abstract: [Figure not available: see fulltext.]

OBJECTIVES: The objective of the study was to assess the diversity of mosquitoes in various towns of the southern belt of KPK. METHODOLOGY: This was a descriptive study that was conducted in numerous towns of Western belt of Khyber Pakhtunkhwa. The study areas were Darra Adam Khel, District Kohat, District Karak, District Banu, District D.I. Khan and newly merged districts Mir Ali and Miranshah. From each study site, the samples were collected randomly. The sample collection was done through survey and area visits whereas; the identification process was done in a parasitology laboratory of Hayatabad-Peshawar. Sampling was done from June 2016 to May 2017. RESULTS: A total of 2150 adult mosquitoes were gathered and collected from 42 different locations of the southern belt of KPK and were identified. Based on their identification, 5 genera of the mosquitoes were recognized which were Culex, Anopheles, Psorophora, Aedes and Uranotenia. Culex was found to be most dominant in all the visited areas with a percentage of 12.65 in Miranshah followed by 11.81 in Mirali, 7.16 in Karak, 6.88 in Darra Adam Khel, 6.69 in D.I.Khan, 6.41 in Kohat and 5.11 in Bannu respectively. The results of our findings also revealed the presence of Culex genera in all the habitats and remained the dominant genera among the others followed by Anopheles and Psorophora. Aedes was found in the habitat of plants and grasses etc. whereas Uranotenia was found in marsh/swampy areas as well as in plants/grasses habitat only. CONCLUSION: The outcomes reveal that a climate shifting and extensive urbanization process is enforcing the diversity of mosquitos’ fauna in the southern belt of KPK.

Vector-borne diseases, especially those transmitted by mosquitoes, have severe impacts on public health and economy. West Nile virus (WNV) and avian malaria parasites of the genus Plasmodium are mosquito-borne pathogens that may produce severe disease and illness in humans and birds, respectively, and circulate in an endemic form in southern Europe. Here, we used field-collected data to identify the impact of Culex pipiens, Cx. perexiguus and Cx. modestus, on the circulation of both WNV and Plasmodium in Andalusia (SW Spain) using mathematical modelling of the basic reproduction number (R0). Models were calibrated with field-collected data on WNV seroprevalence and Plasmodium infection in wild house sparrows, presence of WNV and Plasmodium in mosquito pools, and mosquito blood-feeding patterns. This approach allowed us to determine the contribution of each vector species to pathogen amplification. Overall, 0.7% and 29.6% of house sparrows were positive to WNV antibodies and Plasmodium infection, respectively. In addition, the prevalence of Plasmodium was higher in Cx. pipiens (2.0%), followed by Cx. perexiguus (1.8%) and Cx. modestus (0.7%). Three pools of Cx. perexiguus were positive to WVN. Models identified Cx. perexiguus as the most important species contributing to the amplification of WNV in southern Spain. For Plasmodium models, R0 values were higher when Cx. pipiens was present in the population, either alone or in combination with the other mosquito species. These results suggest that the transmission of these vector-borne pathogens depends on different Culex species, and consequently, their transmission niches will present different spatial and temporal patterns. For WNV, targeted surveillance and control of Cx. perexiguus populations appear as the most effective measure to reduce WNV amplification. Also, preventing Culex populations near human settlements, or reducing the abundance of these species, are potential strategies to red

BackgroundAerial applications of insecticides that target adult mosquitoes are widely used to reduce transmission of West Nile virus to humans during periods of epidemic risk. However, estimates of the reduction in abundance following these treatments typically focus on single events, rely on pre-defined, untreated control sites and can vary widely due to stochastic variation in population dynamics and trapping success unrelated to the treatment.MethodsTo overcome these limitations, we developed generalized additive models fitted to mosquito surveillance data collected from CO2-baited traps in Sacramento and Yolo counties, California from 2006 to 2017. The models accounted for the expected spatial and temporal trends in the abundance of adult female Culex (Cx.) tarsalis and Cx. pipiens in the absence of aerial spraying. Estimates for the magnitude of deviation from baseline abundance following aerial spray events were obtained from the models.ResultsAt 1-week post-treatment with full spatial coverage of the trapping area by pyrethroid or pyrethrin products, Cx. pipiens abundance was reduced by a mean of 52.4% (95% confidence intrval [CI] - 65.6, - 36.5%) while the use of at least one organophosphate pesticide resulted in a mean reduction of 76.2% (95% CI - 82.8, - 67.9%). For Cx. tarsalis, at 1-week post-treatment with full coverage there was a reduction in abundance of 30.7% (95% CI - 54.5, 2.5%). Pesticide class was not a significant factor contributing to the reduction. In comparison, repetition of spraying over three to four consecutive weeks resulted in similar estimates for Cx. pipiens and estimates of somewhat smaller magnitude for Cx. tarsalis.ConclusionsAerial adulticides are effective for achieving a rapid short-term reduction of the abundance of the primary West Nile virus vectors, Cx. tarsalis and Cx. pipiens. A larger magnitude of reduction was estimated in Cx. pipiens, possibly due to the species' focal distribution. Effects of

During the 2019 Eastern equine encephalitis virus (EEEV) outbreak in Michigan, two 2-month old Mexican wolf pups experienced neurologic signs, lymphohistiocytic neutrophilic meningoencephalitis with neuronal necrosis and neuronophagia, and acute death. We identified EEEV by reverse transcription real-time PCR and in situ hybridization. Vector mosquitoes were trapped at the zoo.

As a result of our work, we set the goal of identifying the species composition and number of mosquitoes in foci of cutaneous leishmaniasis. To obtain the results, we caught mosquitoes using sticky sheets of paper, which were installed in residential, utility rooms and colonies of large gerbils 1 hour before sunset. As a result, they beat getting the following results.The main vectors (CL) of leishmaniasis - P. papatasi, P. sergenti are ubiquitous in the surveyed territories of Uzbekistan.Due to the dominant position of P. sergenti among other species of leishmaniasis vectors in Jizzakh regions, the occurrence of LAC may become more frequent in the coming years.

According to official data, the incidence of cutaneous leishmaniasis is the last 5 years; in endemic areas, Uzbekistan is growing markedly. Given the increase in the incidence rate among the population of the republic, it is necessary to conduct an annual epidemiological analysis of the detection and spread of this disease, with the aim of timely monitoring and prevention. [1,4,5]

Mosquitoes that are human-feeding specialists vector several pathogens responsible for hundreds of thousands of deaths each year. Mosquitoes use odor to locate humans and to tell them apart from other potential hosts. By understanding how mosquitoes follow odor plumes, and which odor components they use, we may be able to improve traps used for vector surveillance. First, to examine host finding in female Aedes aegypti, a diurnal biting mosquito, we used a small source of skin odor that was visually indistinguishable from its surroundings. Despite being thought of as a visually guided mosquito, we found Ae. aegypti landed on a visually indistinguishable patch of odor. A blend of lactic and ketoglutaric acids elicits landings in a cage assay. We found, in a wind tunnel assay, that this blend elicits takeoff, upwind flight, and landing of Ae. aegypti, even without the addition of CO2. This property makes the blend of lactic and ketoglutaric acids a candidate for use in mosquito traps because suppling CO2 to traps in the field is logistically challenging. Finally, we tested the landing response of wild type Ae. aegypti and two genotypes lacking Ir8a or orco receptors. Aedes aegypti lacking the Ir8a coreceptor, required for lactic acid detection, landed on the blend of lactic and ketoglutaric acid at half of the rate of wild type mosquitoes. This shows that a receptor other than Ir8a is responsible for the detection of ketoglutaric acid. Future studies will be able to determine how Ae. aegypti detect ketoglutaric acid.

To avoid detection during a bloodmeal, a mosquito must minimize contact forces during attachment and detachment contact while maintaining sufficient grip to insert their proboscis and feed. Measuring contact mechanics of the mosquito is technically challenging due to the small length and force scales. Because of this, many aspects of blood feeding are still poorly understood. We developed an optic measurement set-up that enables the observation of contact dynamics when mosquitoes are host-seeking and blood feeding. Using frustrated total internal reflection (FTIR) we were able to record contact dynamics of freely flying mosquitoes at a spatial resolution of 25µm2 per pixel and a temporal resolution of 500 Hz. While useful given its non-invasiveness, FTIR as a technique may lack reproducibility due to the subjectivity in defining an intensity threshold that signifies contact. At these time and length scales, low signal-to-noise ratio may amplify variations in contact areas measured given selections in intensity thresholds. We developed a systematic approach to select contact thresholds for large image sets, allowing for standardized high-throughput FTIR studies. Our results suggest that probing behaviour, characterized as rapid pulling of the fore and mid legs towards the body during contact, might be less related to surface evaluation via sensing than previously thought, and more related to establishing sufficient grip to insert the proboscis. This new perspective illustrates the need for further investigation into the contact dynamics of mosquitoes during blood feeding to understand the mechanisms that enable the transmission of vector-borne diseases, such as malaria, between hosts., Biomedical Engineering | Bioelectronics

West Nile virus (WNV) is an arthropod-born pathogen, which is transmitted from wild birds through mosquitoes to humans and animals. At the end of the 20th century, the first West Nile fever (WNF) outbreaks among humans in urban environments in Eastern Europe and the United States were reported. The disease continued to spread to other parts of the continents. In Serbia, the largest number of WNV-infected people was recorded in 2018. This research used spatial statistics to identify clusters of WNV infection in humans and animals in South Banat County, Serbia. The occurrence of WNV infection and risk factors were analyzed using a negative binomial regression model. Our research indicated that climatic factors were the main determinant of WNV distribution and were predictors of endemicity. Precipitation and water levels of rivers had an important influence on mosquito abundance and affected the habitats of wild birds, which are important for maintaining the virus in nature. We found that the maximum temperature of the warmest part of the year and the annual temperature range; and hydrographic variables, e.g., the presence of rivers and water streams were the best environmental predictors of WNF outbreaks in South Banat County.

Mosquitoes, by transmitting vector-borne diseases through their saliva, impact nearly half of the world's population. Mosquito survival is dependent on their sense of smell, or olfaction, which allows a mosquito to differentiate between plant nectar, required for metabolic processes, and host odors, which will help them navigate towards hosts, source of the blood required for producing eggs. Mosquitoes interpret and respond to chemical volatiles very differently depending on their environment (temperature, humidity, time of day, etc.) and species-specific host preferences (humans, mammals, etc.). However, the impact of ecological factors on mosquito prevalence, sugar-feeding, and host seeking is relatively unknown. In an attempt to address this knowledge gap, we first investigate how several ecological factors (i.e., temporal, seasonal, and topographical) affect mosquito sugar feeding and population dynamics. Second, we focused on the anthropophilic mosquito species Aedes aegypti to investigate the role of plant associated compounds in host-seeking behavior, such as those which are commonly found in personal care products (i.e., body washes). Our results demonstrate that several ecological factors alter mosquito prevalence and behavior, including both sugar and host seeking behaviors. We anticipate these results to be a starting point for mosquito control strategies that depend not only on olfactory perception of plant odors, but also on the ecological and species-specific characteristics which shape the dynamics of vector-borne diseases.

Aedes aegypti mosquitoes are found globally and also act as the primary vector of Zika, dengue, and Chikungunya viruses, for which there are limited treatment options and no vaccines available. The use of insecticides as the main control strategy against diseases transmitted by this mosquito, is increasingly challenged by emerging resistance. Thus, there is a dire need for the development of novel approaches informed by an improved understanding of mosquito biology, to control mosquito populations and, ultimately, disease transmission. Rhythmic biological processes in mosquitoes help optimize resource exploitation by coordinating behaviors and physiology with fluctuating environmental conditions. Such synchronization enables organisms to adjust their physiology, metabolism, and behavior to predictable external cycles. In mosquitoes, circadian rhythmicity has been demonstrated in their biting and oviposition behavior, as well as their locomotor activity. However, little is known regarding how responses to long-range host cues are modulated by the circadian system. Here we show that both antennal sensitivity and olfactory behavior are time-of-day and odor-specific in Ae. aegypti females. Global transcriptomic analysis in whole heads of Ae. aegypti females reveal chemosensory genes differentially expressed throughout the day, providing insight into the molecular mechanisms behind daily variations in olfactory sensitivity and behaviors. We additionally show an odor-induced activation of mosquito behavior. Mosquito locomotion and behavior are also mediated by physiological state, and activity decreases after blood-feeding. Since the central clock components have been shown in other organisms to be redox-sensitive, we explored the role that diet heme plays in mediating behavioral changes following blood ingestion using artificial blood diets. We found that the transcription of the timekeeping gene period is reduced in the head immediately after feeding on a meal containin

The yellow fever mosquito (Aedes aegypti) is an important pathogen vector and model organism for mosquito researchers. Gene silencing by RNA interference (RNAi) has been used to determine genes’ functions in the vinegar fly, Drosophila melanogaster, but comparable, genome-wide loss-of-function data are not available for mosquitoes. This is due to the difficulty of achieving transcript depletion by dsRNA feeding and to the complexity and size of the Ae. aegypti genome. To respond to these challenges, I set out to understand dsRNA degradation in the mosquito gut, analyze the transcriptome of male and female mosquito larvae and improve dsRNA delivery methods. Several enzymes predicted to degrade dsRNA are found in the mosquito genome. I suspected that some of these enzymes could reduce RNAi efficiency of ingested dsRNAs in the larvae. I identified ten putative nuclease genes in the insect’s genome, two of which are expressed in the gut of fourth instar larvae. By delivering dsRNA against these nuclease genes, RNAi efficiency against other transcripts was improved. Sex determination in mosquitoes is controlled by a cascade of differentially-spliced transcripts that encode different transcription factors in the two sexes. To explore whether genes other than the few sex-determination genes are also spliced in a sex-specific manner, I used nanopore sequencing to sequence full-length transcripts from single reads in sex-sorted fourth instar larvae. This is the stage where development of sex organs begins, and I targeted some of these sex-biased transcripts using RNAi, inducing female-specific mortality. I also described several male-biased genes which may provide effective targets to produce sterile males. To enable low-cost RNAi assays, I developed and optimized dsRNA expression systems in bacteria and yeast. An understanding of dsRNA degradation, together with identification of new sex-specific gene targets and improved dsRNA delivery methods will allow researchers to exp

The essay maps and reflects on some dimensions of human–mosquito interaction in the context of the Arctic and inspired by fieldwork in Finnish Lapland. Rather than developing any particular argument, we seek to document this thinking mosquito as a collection of glimpses, fragments and musings. This impressionistic approach was inspired by conversations among the authors and with environmental humanities scholarship about the roles non-humans play in human worlds, and about how one might engage with mosquitos in thinking about scientific fieldwork, about everyday life in various environments, and about the Arctic more generally. The essay does not provide answers but rather questions, hoping as it does to offer some insights into the complexity of issues that connect mosquito worlds to human worlds. As a mirror to these reflections, we dialogue with excerpts from our own creative written thoughts from the field and from the diaries of German soldiers based in Lapland during the Second World War.

Condition-specific competition, when environmental conditions alter the outcome of competition, can foster the persistence of resident species after the invasion of a competitively superior invader. We test whether condition-specific competition can facilitate the areawide persistence of the resident and principal West Nile virus vector mosquito Culex pipiens with the competitively superior invasive Aedes albopictus in water from different urban container habitats. (2) Methods: We tested the effects of manipulated numbers of A. albopictus on C. pipiens’ survival and development in water collected from common functional and discarded containers in Baltimore, MD, USA. The experiment was conducted with typical numbers of larvae found in field surveys of C. pipiens and A. albopictus and container water quality. (3) Results: We found increased densities of A. albopictus negatively affected the survivorship and development of C. pipiens in water from discarded containers but had little effect in water from functional containers. This finding was driven by water from trash cans, which allowed consistently higher C. pipiens’ survival and development and had greater mean ammonia and nitrate concentrations that can promote microbial food than other container types. (4) Conclusions: These results suggest that the contents of different urban containers alter the effects of invasive A. albopictus competition on resident C. pipiens, that trash cans, in particular, facilitate the persistence of C. pipiens, and that there could be implications for West Nile virus risk as a result.