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Mosquitoes are responsible for the spread and transmission of several diseases including malaria, a dreaded disease that still affects nearly half of the world population. This study was conducted in Kontagora, a metropolitan urban settlement in North-Central Nigeria to evaluate the spartial and temporal distribution of Anopheline mosquitoes. Adult mosquitoes were collected from five (5) sampling sites widely located in Kwangwara, Tudun wada, Dadin kowa, Sabon gari and Usubu areas of Kontagora metropolis. The mosquitoes were morphologically identified to Anophelines using standard taxonomic keys with the aid of Trinocular Microscope. Data generated revealed that spartial distribution of Anopheline mosquitoes Mean ±SE across the study areas occurred in the following order of decreasing abundance; Kwangwara (11.25±1.03) > Tudun wada (9.30 ±0.77) > Sabon gari (8.96±0.78), > Dadin kowa (8.92±0.88) > Usubu (8.59±0.82) with no significant variation (P>0.05) between sampling locations. However, the monthly distribution of Anopheline mosquitoes revealed high abundance of Anopheline vectors Mean ±SE in August (14.00±2.91) and low abundance in March (3.80±1.57), with significant variation (p

Rooted in Chantal Mouffe’s conceptualisation of agonistic pluralism and Jacques Rancière’s work on dissensus, this article analyses the debate scenes of British playwright Lucy Kirkwood’s plays: Mosquitoes (2017) and The Welkin (2020). In Performing Antagonism Tony Fisher suggests that the politics of theatre and performance has formally pivoted towards “a critical politics of the visible.” The article asks what this implies in Kirkwood’s drama. In a contradictory present conjuncture where multiple forms of crisis overlap and interact, Kirkwood’s recent work hones polarised, gendered, antagonistic scenes of encounter where the challenges of dialogue, of understanding and of ethical relations are repeatedly articulated. Through close attention to the ways agonism and antagonism are embodied in the plays, the article argues that for Kirkwood dissensus operates to enact a feminist “critical politics of the visible” in which mutual recognition and resilience are keynotes.

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 lineages of the Maculipennis Group. Conclusions Our phylogenomic analyses reveal migration routes and adaptive radiation timing of Holarctic malaria vectors and strongly support the inclusion of An. beklemishevi into the Maculipennis Subgroup. Detailed knowledge of the evolutionary history of the Maculipennis Subgroup provides a framework for examining the genomic changes related to ecological adaptation and susceptibility to human pathogens. These genomic variations may inform researchers about similar changes in the future providing insights into the patterns of disease transmission in Eurasia.

Mesocosm experiments enable researchers to study animal dynamics, but determining accurate estimates of survival and development rates of different life stages can be difficult, especially as the subjects may be hard to sample and mortality rates can be high. We propose a new methodology for estimating such parameters.We used an experimental set-up with 48 aquatic mesocosms, each with 20 first instar mosquito larvae and under 1 of 12 treatments with varying temperatures and nutrient concentrations. We took daily subsamples of the aquatic life stages as well as counting the emerging adults. We developed a method to estimate the survival and development probabilities at each life stage, based on optimising a matrix population model. We used two different approaches, one assuming the difference between predictions and observations was normally distributed, and the other using a combination of a normal and a multinomial distribution. For each approach, the resulting optimisation problem had around 100 parameters, making conventional gradient descent ineffective with our limited number of data points. We solved this by computing the formal derivatives of our matrix model.Both approaches proved effective in predicting mosquito populations over time, also when compared against a separate validation dataset, and the two approaches produced similar results. They also both predicted similar trends in the survival and development probabilities for each life stage, although there were some differences in the actual values. The approach which only used the normal distribution was considerably more computationally efficient than the mixed distribution approach.This is an effective approach for determining the survival and development rates of small animals in mesocosm experiments. We have not found any other reliable methodology for estimating these parameters, especially not from incomplete data or when there are many different experimental treatments. This methodology enables researchers to gain a much more detailed understanding of the life cycles of small animals, potentially leading to advances in a wide range of areas, for example in mosquito-borne disease risk or in considering the effects of biodiversity loss or climate change on different species.

Insecticide resistance is the major threat to vector control and for the prevention of vector-borne diseases. Because almost all insecticides used against insect vectors are or have been used in agriculture, a connection between agricultural insecticide use and resistance in insect vectors has been hypothesized. However, it is challenging to find a causal link between past agricultural use of insecticides and current resistance in vector populations without historical data series. Here we investigated the relative contribution across time of agricultural and public-health insecticide applications in selecting for diflubenzuron (DFB) resistance in Culex pipiens populations. Using DNA sequencing, we looked for DFB resistant mutations in current and historical mosquito samples, dating back to the 1980s-1990s, when DFB was used in agriculture but not yet in mosquito control.In the samples collected before the introduction of DFB in vector control, we found the resistant mutation I1043M in rural regions but not any of the neighboring urban and natural areas, indicating that the selection pressure was derived by agriculture. However, after the introduction of DFB for vector control, the resistant mutations were found across all study areas showing that the initial selection from agriculture was further boosted by the selection pressure imposed by the mosquito control applications in the 2000s.Our findings support a combined role of agricultural and public-health use of insecticides in vector resistance across time and call for specific actions in integrated resistance management, including increased communication between agriculture and health practitioners. © 2022 The Authors. Pest Management Science published by John WileySons Ltd on behalf of Society of Chemical Industry.

Aedes pulcritarsis is a tree-hole breeding species with its main distribution in the Mediterranean area. Within the scope of two independent monitoring programmes, this mosquito species was detected for the first time in Austria, in the province of Lower Austria (2018, districts Mistelbach and Gaenserndorf; 2020, district Bruck an der Leitha). As the climatic and habitat situation in Central Europe seems to be generally suitable for this species, the most likely explanation for the species not being recorded previously is that it might have been overlooked in the past due to its specialized breeding habitat. However, further research on the distribution of Ae. pulcritarsis in Austria would be needed to support this hypothesis. The results from this study will contribute to the investigation of the northern distribution limit of Ae. pulcritarsis in Europe and possible changes thereof.

Mosquitoes that can transmit viral pathogens of humans (e.g., Aedes, Anopheles, and Culex genera) are of increasing concern for global public health. These vectors not only cause a rapidly growing infectious disease burden (e.g., malaria, dengue, Zika, chikungunya, yellow fever), but are also spreading in geographic range under climate change. As small-bodied ectotherms, mosquitoes are strongly affected by temperature, and prior laboratory research has demonstrated nonlinear and unimodal relationships between temperature and mosquito life history traits, with upper and lower thermal limits and intermediate thermal optima as predicted by first principles of enzyme kinetics and the metabolic theory of ecology. However, it remains unknown how mosquito thermal responses measured in laboratory experiments relate to the realized thermal responses of mosquitoes in the field. To address these questions, we leverage thousands of global mosquito occurrences and geospatial satellite rasters at high temporal and spatial resolution to construct machine-learning based species distribution models. We apply new methods to restrict models to the temporally-relevant mosquito activity season and to ecologically-relevant spatial background sampling for comparison to mosquito occurrence records. Thermal response signatures from these ‘top-down’ statistical models supported the nonlinear temperature responses apparent in the laboratory-derived mosquito abundance estimates. Further, we found that, across mosquitoes, thermal minima estimated from laboratory studies were highly correlated with those estimated from field-based models. However, we could not estimate thermal maxima from field occurrence records due to inherent limitations in background sampling, and comparisons of thermal optima were inconclusive. Together, the current evidence suggests that laboratory studies have the potential to be highly transportable to real-world mosquito inferences for thermal minima, while other key temperature dependence metrics merit further investigation.

We detected Rift Valley fever virus (RVFV) IgM and IgG in human serum samples collected during 2018–2019 in northern KwaZulu-Natal Province, South Africa. Our results show recent RVFV circulation and likely RVFV endemicity in this tropical coastal plain region of South Africa in the absence of apparent clinical disease.

Among 713 equids sampled in northeastern Brazil during 2013-2018, West Nile virus seroprevalence was 4.5% (95% CI 3.1%-6.3%). Mathematical modeling substantiated higher seroprevalence adjacent to an avian migratory route and in areas characterized by forest loss, implying increased risk for zoonotic infections in disturbed areas.

U.S. military troops are exposed to mosquito-borne pathogens when deployed to endemic regions. Personal protective measures such as permethrin-treated uniforms and dermal repellents are the cornerstones of mosquito-borne disease prevention for the U.S. military. These measures have limitations and additional personal protection tools, such as spatial repellent devices to decrease the risk of vector-borne pathogen transmission, are required. Novel spatial repellent controlled-release devices formulated with metofluthrin were evaluated in an outdoor setting in the northern Amazon of Peru to evaluate performance under field conditions. The metofluthrin emitting devices lowered the number of mosquitoes captured in protected human landing collections (HLC) compared to blank devices, although there were effect differences between Anopheles spp. and species in other mosquito genera. A computational-experimental model was developed to correlate HLC and active ingredient (AI) concentrations as a function of time and space. Results show a strong correlation between the released AI and the decrease in HLC. This model represents the first effort to obtain a predictive analytical tool on device performance using HLC as the entomological endpoint.

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 neighborhood 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., m CSIC under grant number 202030E263, Research State Agency under grant numbers PGC2018-095704-B-I00 and PID2020-116768RR-C21/C22 FEDER, European Commission – NextGenerationEU (Regulation EU 2020/2094), Instituto de Salud Carlos III Project “PI19CIII_00014”

Raw data for project examining Culex mosquito oviposition preferences

This study of mosquitoes in Lika, geographically, geologically and climatically a very specific region, was conducted to gain insight into the composition and relative abundance of the mosquito fauna, as well as to check for the possible presence of invasive species. Sampling took place from July to September 2020. Mosquito larvae were captured from medium and small breeding sites using a 25 cm diameter net and a plastic dipper. Adult specimens were sampled in both urban and rural areas using CO2 baited CDC traps, CO2 baited BG Sentinel traps with BG Lure and human landing catch. The study was conducted at 69 sites. We collected 5,126 specimens (100 adults and 5,026 larvae) and demonstrated the presence of 16 mosquito species. CDC traps were almost five times more effective (quantity and quality) than BG Sentinel traps. The most common mosquito taxa caught in Lika were Culex pipiens complex (78.36% of all larvae) and Ae. geniculatus (30.26% of all adults). Both invasive mosquito species present in Croatia, Aedes albopictus and Ae. japonicus, were recorded, with Ae. albopictus being detected in Lika for the first time. Aedes japonicus was widespread, recorded in 23 localities. According to molecular analysis, only An. maculipennis s.s. was confirmed in the An. maculipennis complex. Within the Cx. pipiens complex, both Cx. pipiens biotypes, pipiens and molestus were confirmed together with one single hybrid specimen. Analysis of mosquito occurrence with regard to altitude shows that most samples and species were collected between 601 and 700 m a.s.l., although the Shannon evenness index and Hill’s index show the highest value in the range of 901 to 1140 m a.s.l. In this systematic study on the mosquito fauna in Lika, a significant species diversity, including invasive species, was found.

The current condition of our planet is alarming, as the Earth is experiencing both global warming and a mass extinction of species: two human induced phenomena devastating our environment. The reason for these crises is neither lack of knowledge about their source, nor the absence of the technical means to deal with them: what we lack is the capacity to act jointly, through global political mechanisms allowing a coordinated effort to change our behavior. While such mechanisms may be difficult to imagine, this research note suggests that a precedent for such a coordinated global environmental action may be found in the worldwide campaigns against mosquito borne diseases (MBD) which were carried out during the twentieth century. Pointing at some similarities and several dissimilarities between the combats against MBDs and a possible global effort which may be initiated nowadays, this research note calls for drawing lessons from the past dealing with MBDs for learning how to cope with our current global environmental challenges.

A new Getah virus (GETV) strain, B254, was isolated from Culex fuscocephalus mosquitoes captured at Mount Ophir, Malaysia, in 2012. Phylogenetic analyses revealed that GETV B254 is distinct from the old Malaysia GETV MM2021 strain but closely related to group IV GETV from Russia (LEIV16275Mag), China (YN12031), and Thailand (GETV/SW/Thailand/2017).

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.

A specific mosquito enzyme, 3-hydroxykynurenine transaminase (HKT), is involved in the processing of toxic metabolic intermediates of the tryptophan metabolic pathway. The HKT enzymatic product, xanthurenic acid, is required for Plasmodium spp. development in the mosquito vectors. Therefore, an inhibitor of HKT may not only be a mosquitocide but also a malaria-transmission blocker. In this work, we present a study investigating the evolution of HKT, which is a lineage-specific duplication of an alanine glyoxylate aminotransferases (AGT) in mosquitoes. Synteny analyses, together with the phylogenetic history of the AGT family, suggests that HKT and the mosquito AGTs are paralogous that were formed via a duplication event in their common ancestor. Furthermore, 41 amino acid sites with significant evidence of positive selection were identified, which could be responsible for biochemical and functional evolution and the stability of conformational stabilization. To get a deeper understanding of the evolution of ligands’ capacity and the ligand-binding mechanism of HKT, the sequence and the 3D homology model of the common ancestor of HKT and AGT in mosquitoes, ancestral mosquito AGT (AncMosqAGT), were inferred and built. The homology model along with 3-hydroxykynurenine, kynurenine, and alanine were used in docking experiments to predict the binding capacity and ligand-binding mode of the new substrates related to toxic metabolites detoxification. Our study provides evidence for the dramatic biochemical evolution of the key detoxifying enzyme and provides potential sites that could hinder the detoxification function, which may be used in mosquito larvicide and design.

Insect-borne diseases are responsible for important burdens on health worldwide particularly in Africa. Malaria alone causes close to half a million deaths every year, mostly in developing, tropical and subtropical countries, with 94% of the global deaths in 2019 occurring in the WHO African region. With several decades, vector control measures have been fundamental to fight against malaria. Considering the spread of resistance to insecticides in mosquitoes and to drugs in parasites, the need for novel strategies to inhibit the transmission of the disease is pressing. In recent years, several studies have focused on the interaction of malaria parasites, bacteria and their insect vectors. Their findings suggested that the microbiota of mosquitoes could be used to block Plasmodium transmission. A strategy, termed paratransgenesis, aims to interfere with the development of malaria parasites within their vectors through genetically-modified microbes, which produce antimalarial effectors inside the insect host. Here we review the progress of the paratransgenesis approach. We provide a historical perspective and then focus on the choice of microbial strains and on genetic engineering strategies. We finally describe the different steps from laboratory design to field implementation to fight against malaria.

The prevalence, intensity and some vector dynamics of malaria in two communities of Anambra East Local Government Area LGA was carried out using standard parasitological and entomological techniques for rapid assessment of malaria infection, level of parasitaemia and morphological features of mosquitoes. Results showed an overall malaria RDT (Rapid Diagnostic Test) prevalence of 22% and community based prevalence of 13 (30%) and 22(24%) for Umuoba -Anam and Nando respectively. Overall, age related prevalence in the Anambra West LGA showed that the age bracket 35 to 42 years had the highest malaria prevalence 3(42.9 %). Overall sex related prevalence in Anambra East LGA showed no statistical significance in prevalence among males (12.0%) and females (10.0%) (P500-2000 parasites/µl) parasitaemia. There was no high parasitaemia recorded in Umuoba-Anam. Overall, a total of 225 mosquitoes were encountered with anopheles making up 61%. A hundred and twenty one (53.8% of the total mosquito population in the study was found to be unfed with blood meal whereas 54(24%) and 50 (22.2%) were freshly and previously fed respectively. One hundred and twenty one (53.8%) of the mosquitoes appeared non-gravid against 82(36.4%) that are gravid. The mosquitoes encountered wereAnopheles gambiae31(13.8%),Anopheles funestus77(34.22%), andCulexSpecie117(52%). The two communities recorded variations in prevalence, intensity and vector dynamics. There should be intensified effort to continuously educate the masses on all the strategies of malaria prevention.

Dirofilaria immitis and Dirofilaria repens are mosquito-borne filarioids of zoonotic concern, which primarily cause canine heartworm disease (HWD) and subcutaneous dirofilariosis, respectively. The geographical distribution of these nematodes is constantly changing, due to many factors such as the colonization by new invasive mosquito species, the increased movement of animals and the absence of chemoprophylactic strategies in non-endemic regions. Although HWD has always been considered endemic in northern Italy, an increase in the prevalence of this disease has been recorded in the last decades in central and southern regions. We describe the southernmost hyperendemic European focus of heartworm disease in the Pelagie archipelagos. From June to November 2020, 157 dogs and 46 cats were sampled in Linosa and Lampedusa islands for the detection of Dirofilaria immitis and Dirofilaria repens by modified Knott's, rapid antigen and molecular tests. Mosquitoes were collected using CDC light and BG sentinel-2 traps and aspirators, and tested for host blood meal and Dirofilaria spp. DNA. Out of 56 dogs in Linosa and 101 in Lampedusa, 33 (i.e. 58.9%) and 8 (i.e. 7.9%) were positive to D. immitis and D. repens, respectively. Three cats scored positive to D. immitis (i.e. 17.6%) in Linosa. Six mosquito species were identified, and the abdomen of a non-engorged Aedes albopictus was positive for D. immitis and human DNA. The results suggest that D. immitis infection could spread to new previously non-endemic territories in southern Europe, representing a real threat to animal and human health.

The purpose of this study is to assess the effectiveness of paracord anklet and bracelet made up of guyabano (Annona Muricata) seeds and wormwood plant (Artemisia Absinthium) extract as mosquito repellent and to determine if the paracord anklet and bracelet can be as effective as the commercial patch used in this study. In the study, 2 groups were examined: The experimental group and the control group. The experimental group with variation 1 (50 guyabano seed, 80% of water, and wormwood extract), variation 2 (75 Guyabano seed, 50% of water, and wormwood extract), and variation 3 (100 Guyabano seed, 30% of water, and wormwood extract). The control group was tested with the commercialized patch. Results showed that the overall gathered data showed very promising effectiveness, with a level of effectiveness of 6.5 means. Furthermore, the ANOVA showed no differences at all between the Control and Experimental Group (fcalc 2.20fcrit3.49, P=0.13). This may therefore mean that the paracord anklet and bracelet made up of guyabano and wormwood plant is as effective as the commercial patch used in this study. This study shows that the paracord anklet and bracelet can be considered as an alternative and environmentally friendly mosquito repellent.

For effective control of vector-borne diseases and control of nuisance-biting insects, it is important to know which species are present and their relative abundance. In this study, we report data from a State-supported mosquito surveillance program in Kyiv, Ukraine's capital city. The surveillance identified 29 different species: 24 Culicines and 5 Anopheline species. Culicine mosquitoes included 17 in the genus Aedes, 3 Culex, 3 Culiseta, and 1 Mansonia species. The relative abundance of each genera was consistent in years 2014, 2015, and 2016; namely Aedes>Culex>Anopheles. In 2017, Aedes and Culex mosquitoes were approximately the same, predominating over Anopheles. A declining trend in the numbers of mosquitoes collected from 2013 to 2017 has not only several potential explanations, including increased urbanization and more effective control, but also may reflect changes in surveillance efforts.

Mosquito vectors captured at a crime scene are forensically valuable since they feed on human blood, and hence, human DNA can be recovered to help identify the victim and/or the suspect. This study investigated the validity of obtaining the human short tandem repeats (STRs) profile from mixed blood meals of the mosquito, Culex pipiens L. (Diptera, Culicidae). Thus, mosquitoes were membrane-feed on blood from six different sources: a human male, a human female, mixed human male-female blood, mixed human male-mouse blood, mixed human female-mouse blood, and mixed human male-female-mouse blood. DNA was extracted from mosquito blood meals at 2 h intervals up to 72 h post-feeding to amplify 24 human STRs. Data showed that full DNA profiles could be obtained for up to 12 h post-feeding, regardless of the type of blood meal. Complete and partial DNA profiles were obtained up to 24 h and 36 h post-feeding, respectively. The frequencies of STR loci decreased over time after feeding on mixed blood until they became weakly detectable at 48 h post-feeding. This may indicate that a blood meal of human blood mixed with animal blood would contribute to maximizing DNA degradation and thus affects STR identification beyond 36 h post-feeding. These results confirm the feasibility of human DNA identification from mosquito blood meals, even if it is mixed with other types of non-human blood, for up to 36 h post-feeding. Therefore, blood-fed mosquitoes found at the crime scene are forensically valuable, as it is possible to obtain intact genetic profiles from their blood meals to identify a victim, a potential offender, and/or exclude a suspect.

Mosquito transmission of dengue viruses to humans starts with infection of skin resident cells at the biting site. There is great interest in identifying transmission-enhancing factors in mosquito saliva in order to counteract them. Here we report the discovery of high levels of the anti-immune subgenomic flaviviral RNA (sfRNA) in dengue virus 2-infected mosquito saliva. We established that sfRNA is present in saliva using three different methods: northern blot, RT-qPCR and RNA sequencing. We next show that salivary sfRNA is protected in detergent-sensitive compartments, likely extracellular vesicles. In support of this hypothesis, we visualized viral RNAs in vesicles in mosquito saliva and noted a marked enrichment of signal from 3'UTR sequences, which is consistent with the presence of sfRNA. Furthermore, we show that incubation with mosquito saliva containing higher sfRNA levels results in higher virus infectivity in a human hepatoma cell line and human primary dermal fibroblasts. Transfection of 3'UTR RNA prior to DENV2 infection inhibited type I and III interferon induction and signaling, and enhanced viral replication. Therefore, we posit that sfRNA present in salivary extracellular vesicles is delivered to cells at the biting site to inhibit innate immunity and enhance dengue virus transmission. Support for this research came from a fellowship from the McLauglin Family Foundation to TS, scholarships from the Fondation pour la Recherche Médicale (FRM project SPF202110013925) to HM, from the Institut Méditerranéen Hospitalier (IHU, Marseille) to IMSP and from the graduate school French Ministry of Higher Education and Research to FRC and FR, UTMB start-up funds and Cancer Prevention & Research Institute of Texas grant RP200650 to LJK and MKS, the Ministerio de Ciencia e Innovación (PID2020-115696RB-I00) to MAM-R, Cancer Prevention & Research Institute of Texas grant ID RR210018 to GN, Ministry of Education (Singapore) Tier3 grant (MOE2015-T3-1-003) to RMK and JP, a National Medical Research Council (Singapore) ZRRF grant (ZRRF/007/2017) to JP, a French Agence Nationale de la Recherche grant (ANR-20-CE15-0006) to JP, and the Duke-NUS Signature Research Programme funded by the Agency for Science Technology and Research (A*Star Singapore) and NIH/NIAID P01 AI150585 to MAGB. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Rift Valley fever (RVF) is a zoonotic, vector-borne infectious disease of ruminants and camels transmitted mainly by the Aedes and Culex mosquito species. Contact with the blood or organs of infected animals may infect humans. Its etiological factor is the Rift Valley fever virus (RVFV) of the Phlebovirus genus and Bunyaviridae family. Sheep and goats are most susceptible to infection and newborns and young individuals endure the most severe disease course. High abortion rates and infant mortality are typical for RVF; its clinical signs are high fever, lymphadenitis, nasal and ocular secretions and vomiting. Conventional diagnosis is done by the detection of specific IgM or IgG antibodies and RVFV nucleic acids and by virus isolation. Inactivated and live-attenuated vaccines obtained from virulent RVFV isolates are available for livestock. RVF is endemic in sub-Saharan Africa and the Arabian Peninsula, but in the last two decades, it was also reported in other African regions. Seropositive animals were detected in Turkey, Tunisia and Libya. The wide distribution of competent vectors in non-endemic areas coupled with global climate change threaten to spread RVF transboundarily. The EFSA considers the movement of infected animals and vectors to be other plausible pathways of RVF introduction into Europe. A very low risk both of introduction of the virus through an infected animal or vector and of establishment of the virus, and a moderate risk of its transmission through these means was estimated for Poland. The risk of these specific modes of disease introduction into Europe is rated as very low, but surveillance and response capabilities and cooperation with the proximal endemic regions are recommended.

There are 3559 species of mosquitoes in the world (Harbach 2018) but, so far, only a handful of them have been a focus of olfactory neuroscience and neurobiology research. Here we discuss mosquito olfactory anatomy and function and connect these to mosquito ecology. We highlight the least well-known and thus most interesting aspects of mosquito olfactory systems and discuss promising future directions. We hope this review will encourage the insect neuroscience community to work more broadly across mosquito species instead of focusing narrowly on the main disease vectors.

Dengue prevention and control more reliant on reducing its vector, Aedes sp. mosquitoes by mosquito breeding nest eradication method. Therefore, identification of the primary container of the Aedes sp. breeding site particularly in the urban region of dengue-endemic area is a crucial effort to conduct an effective dengue prevention program. This research aimed to identify the primary container of the Aedes sp. breeding site in the urban region of the dengue-endemic area. This is a descriptive cross-sectional study, located in an urban region of dengue-endemic area within Banyumas Regency of Central Java Indonesia. A total of 300 houses in three urban areas were observed in urban areas of Purwokerto namely Arcawinangun, Purwanegara, and Karangpucung (100 houses each area). A total of 1504 water-holding containers were observed. All container was observed and recorded the type, color, lid condition, position, and the presence of mosquito larvae. The analysis was conducted by calculating the percentage of types, color, lid condition, and position of the container also the presence of mosquito larvae. The result of this study highlighted that flower pots and bathtubs were the primary types of containers with Aedes sp. larvae in the urban area. The characteristics of larvae-positive containers mostly open, bright, and located indoor position. Dengue prevention efforts by targeting the primary types of containers for mosquito breeding are expected to reduce the adult mosquito population.

The purpose of the research is to study the possibility of using the temperature DDU (dirofilaria development units) model for predicting the spread of dirofilariosis in dogs in various regions of the Republic of Armenia.Materials and methods. To obtain temperature models of dirofilariosis in various regions of Armenia, the method of mathematical modeling was applied. The method for determining the number of generations of Dirofilaria spp. infection is based on the effect of the average daily air temperature on the rate of development of Dirofilaria larvae in mosquitoes with a threshold of 14 °C. For a negative value of DDU, the value is set to zero. At temperatures above the threshold, DDU accumulate. For the development of larvae to the infective stage, an amount of 130 DDU is required. The number of possible generations of one generation of larvae L3 was calculated by dividing the annual sum of temperatures above 14 °C by 130 DDU, taking into account that 130 DDU should accumulate within a period not exceeding 30 days. The calculation uses daily data on the average daily air temperature in the period from 2017 to 2019 for Shirak, Aragatston, Armavir and Ararat regions of Armenia.Results and discussion. Temperature modeling of DDU is not of high significance, since it takes into account only the average daily air temperature and does not take into account other factors affecting the incidence rates. The largest number of generations of larvae in mosquitoes could be realized in the Armavir and Ararat regions – on average, 16 generations per year. At the same time, the infection of dogs with dirofilariae in the Armavir region was 42.8%, and in the Ararat region – 29.6%. In Aragatston region, on average, 14–15 generations are developing per year. Dirofilariosis was not detected in the studied dogs. In the Shirak region, on average, 7–8 generations are developing per year. Dirofilariae infection was detected in 3.6% of the dogs studied. Based on the temperature DDU-model of dirofilariosis (on the dates of the end of the first and last incubation of dirofilariosis larvae in mosquitoes for several years), as well as the results of phenological observations, we have developed schemes for effective prevention of dirofilariosis. In order to organize and conduct veterinary preventive measures to prevent infestation of dogs by dirofilariae, it is necessary to organize two lines of defense. The first line of defense: the use of anthelmintics from the group of macrocyclic lactones in Aragatston, Armavir and Ararat regions, which is carried out monthly, and in the Shirak region - from April to January. The second line of defense is repellant treatment of dogs in the Aragatston, Armavir and Ararat regions from March to November, and in the Shirak region from April to October. The practical application of temperature DDU-models of dirofilariosis allows specialists of veterinary and sanitary services to establish the timing of the epizootic season of dirofilariosis, as well as organize and conduct veterinary preventive and therapeutic measures among the population of dogs in endemically disadvantaged areas of the republic.

This study aimed to explore the presence of West Nile Virus (WNV) inside four species of mosquitoes: Culex univittatus (Theobald), Culex quinquefasciatus (Say) Aedes vittatus (Bigot) and Aedes vexans (Meigen). Adult wild mosquitoes were collected from different sites: Soba West, Hellat Kuku, Shambat, and Khartoum North Central Live Stock Market (KCLM). Surveys were carried out at Khartoum State during two phases: pre to the rainy season and post to the rainy season. Mosquito specimens were identified using classical keys then preserved at −80 °C freezer for two weeks till the virus examination using polymerase chain reaction (PCR) were carried out. WNV has been detected inside the three species of mosquitoes: A. vexans, C. univittatus, and C. quinquefasciatus. The species were collected from Hellat Kuku, (Shambat and Hellat Kuku), and (Shambat and KCLM) respectively. Two species of mosquitoes were positive for the virus: C. quinquefasciatus and C. univittatus. Positive results for the virus during the first phase of the study; males of C. quinquefasciatus and C. univittatus collected during the second phase of the study were also tested for the existence of the virus and they were positive. For our knowledge this study represents first record of WNV inside wild mosquitoes in Sudan. PCR technique provided reliable information because specific primer-probe sets were used for the detection of the virus. Extra studies are required to incriminate these species of mosquitoes as potential vectors of WNV.

BACKGROUND: Pregnant women who are infected with malaria usually have more severe symptoms and negative health outcomes than women who are not pregnant, with higher rates of miscarriage, intrauterine demise, premature delivery, low-birth-weight neonates, and neonatal death. Based on evidence from the 2016 Ethiopia Demographic and Health Survey, this study assessed the variation in insecticide-treated nets (ITNs) usage and its associated factors among pregnant women in Ethiopia. METHODS: Data from a total of 1122 women who were pregnant at the time of the survey were included in the final analysis. Bivariate and multilevel analyses were conducted. Multilevel modeling with fixed and random coefficients was used to estimate the variation in pregnant women's ITNs usage across communities (residence areas) and regions of Ethiopia. RESULTS: Out of the total 1122 pregnant women, 58.37% slept under a net and 41.63% did not sleep under nets. Significant variations were observed in pregnant women's ITNs usage across communities (residence areas) and regions of Ethiopia, with between variations in pregnant women's ITNs usage across communities (residence areas) and regions. In addition, the region, place of residence, wealth index, educational level, and age of the women as well as whether they believed that mosquito bites cause malaria were significant factors in pregnant women's usage of ITNs. Pregnant women in Ethiopia had moderate usage of ITNs with varied risk factors at the individual, community, and regional levels. CONCLUSION: Based on the factors identified, there is a need to implement and/or strengthen programs (e.g., regular sensitization) that intensify high coverage of ITNs for effective malaria prevention in Ethiopia, especially among pregnant women who do not use ITNs.

Introduction Access to clean drinking water is a worldwide problem. This water crisis is exacerbated by climate change, pollution, and increasing water consumption. Poor quality drinking water leads to the spread of disease, including cholera and typhoid, and to thousands of deaths across the globe. The World Health Organization estimated 829,000 people die each year from diseases related to poor drinking water. My technical and STS research both explore the issues of drinking water and the technologies used to combat water issues. Technical Project My technical research explores the advancement of the MadiDrop+, a silver-embedded point-of-use ceramic tablet used for the disinfection of water. This research focuses on adding copper mesh to improve the disinfection efficiency of this technology. In communities that have poor-functioning or no access to water treatment systems, people may rely on point-of-use water treatment (POUWT). These communities may also face issues with mosquitoes whose larvae grow in water. So, in addition to assessing the efficiency of the MadiDrop+ with copper mesh, experiments with copper and silver were conducted to test the larvicidal effects of common drinking water technologies on mosquito larvae. STS Research This technical research connects to my STS research which explores the impacts of austerity politics on the quality of water in Puerto Rico. Puerto Rico was chosen as a case study because poor water quality has been caused by its status as a colony and the violence the United States has inflicted upon the archipelago. This paper examines how Puerto Ricans have pushed back against and resisted austerity measures. This research is navigated through the hydropolitics framework, and social movements and mobilized publics framework. Conclusion The experiments with mosquitoes and those with MadiDrops provided interesting insight on the effectiveness of copper and silver on killing mosquitoes and as methods of disinfection. The mosquito experiments proved challenging since new eggs had to be hatched for each set, and, thus, provided a variability of results between each batch of larvae. The MadiDrop+ experiments proved to be promising as they showed consistent release of copper and silver in water. The STS research paper also proved to be insightful as there was a clear connection between austerity and water quality in Puerto Rico. Both research projects gave me a deeper understanding of issues regarding water quality. Acknowledgements I would like to thank my friends and family who supported me in determining the topic of my STS research paper. I would also like to thank Professor Sean Ferguson for his support in writing this paper and tackling such a dense topic. I would like to thank Victoria Cecchetti and Julia Davis for being incredible capstone partners. Finally, I would like to thank Professor James Smith, and PhD candidates Jamie Harris and Sydney Turner for their support and guidance throughout our capstone project and technical report.

Climate shift is thought to be responsible for the spread of vector-born-diseases.Current study was to evaluate the impact of temperature and relative humidity regimes on the developmental stages ofAe. aegyptiand also the effect of population density dependence on the survival ofAe. aegyptilarvae. In addition, the association among the vector larvae abundance, dengue cases incidence and climatic factors were elucidated during 2016-2019 in three populated districts of Punjab Province i.e., Lahore, Rawalpindi and Multan.

We report eight new Culicidae records from San Juan province, Argentina: Anopheles argyritarsis Robineau-Desvoidy, 1827; Anopheles neomaculipalpus Curry, 1931; Culex acharistus Root, 1927; Culex apicinus Philippi, 1965; Culex maxi Dyar, 1928; Culex quinquefasciatus Say, 1823; Culex saltanensis Dyar, 1928; and Haemagogus spegazzinii Brethes, 1912. The geographic distribution of Aedes aegypti (Linnaeus, 1762), Aedes albifasciatus (Macquart, 1838), Anopheles pseudopunctipennis Theobald, 1901, Culex pipiens Linneaus, 1758, Culex tramazayguesi Duret, 1954, and Psorophora cyanescens (Coquillet, 1902) is extended. Data on collection localities, types of breeding sites and health importance are also presented. Fil: Díaz Nieto, Leonardo Martín. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto y Museo de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Murúa Bruna, Albérico Fernando. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto y Museo de Ciencias Naturales; Argentina Fil: Cano Schirado, Florencia Andrea. Ministerio de Salud Publica. - Gobierno de la Provincia de San Juan. Ministerio de Salud Publica.; Argentina Fil: Laurito, Magdalena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; Argentina Fil: Almiron, Walter Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; Argentina Fil: Salvá, Liliana. Ministerio de Salud Publica. - Gobierno de la Provincia de San Juan. Ministerio de Salud Publica.; Argentina

Most malaria in Malaysia is caused by Plasmodium knowlesi parasites through zoonotic infection from macaque reservoir hosts. We obtained genome sequences from 28 clinical infections in Peninsular Malaysia to clarify the emerging parasite population structure and test for evidence of recent adaptation. The parasites all belonged to a major genetic population of P. knowlesi (cluster 3) with high genomewide divergence from populations occurring in Borneo (clusters 1 and 2). We also observed unexpected local genetic subdivision; most parasites belonged to 2 subpopulations sharing a high level of diversity except at particular genomic regions, the largest being a region of chromosome 12, which showed evidence of recent directional selection. Surprisingly, we observed a third subpopulation comprising P. knowlesi infections that were almost identical to each other throughout much of the genome, indicating separately maintained transmission and recent genetic isolation. Each subpopulation could evolve and present a broader health challenge in Asia.

We investigated a case of dengue virus type 1 infection acquired in Benin. Phylogenetic analysis revealed the strain belongs to genotype V but clusters with Asian, rather than with known African, strains. Our finding suggests the introduction of Asian dengue virus in West Africa.

The purpose of study was to isolate arboviruses from mosquitoes of different species in the cell culture and to identify them by using molecular and immunochemical techniques.Materials and methods. Viruses were isolated in C6/36 cell cultures. The pathogens were identified by using enzyme-linked immunosorbent assay (ELISA) kits for detection of antigens of dengue, Chikungunya, West Nile and Sindbis viruses as well as the reverse transcription polymerase chain reaction (RT-PCR) with specific primers and Sanger sequencing.Results. A total of 102 mosquitoes belonging to three genera, Culex spp, Culiseta spp., Aedes spp., were studied. Mosquitoes of each species or genus were divided into pools, each containing 4–5 mosquitoes. The study of suspensions of only 2 mosquito pools obtained from Aedes aegypti and Aedes albopictus, starting from the 3rd passage, showed changes in the C6/36 cell monolayer. Starting from the 4th passage, an antigen of Chikungunya virus was detected using ELISA test in the suspension obtained from the Aedes albopictus pool. Dengue virus was detected in the 5th passage from the materials obtained from the Aedes aegypti pool. Thus, antigens of the Chikungunya and dengue viruses were detected only in 2 of 23 examined pools of mosquitoes of different genera. Materials of the 5th passage were analyzed by RT-PCR with specific primers for dengue and Chikungunya viruses. It was confirmed that the isolate obtained from Aedes albopictus mosquitoes contained RNA of the Chikungunya virus and corresponded to the East/Central/South African genotype, while the isolate obtained from Aedes aegypti mosquitoes contained RNA of the dengue type 2 virus.Conclusion. The obtained nucleotide sequences of the Chikungunya virus were deposited in the GenBank international database under accession numbers MN271691 and MN271692.

Climate change affects the dynamics of vector-borne diseases. Culex pipiens Linnaeus is the main vector of West Nile fever; a widely distributed arbovirus, it is continuously increasing its distribution. Using a species distribution model, maps of suitable habitats of Cx. pipiens were generated for Chile in the current climate and three climate change scenarios, using global and regional georeferenced vector presence records as input, plus bioclimatic variables. Since this virus has not yet arrived in Chile, the purpose of this study is to anticipate potential risk areas and to prevent the establishment and spread of the virus. Cx. pipiens is widely distributed in Chile. The suitable habitats in Chile were concentrated mostly from 32o to 35oS, increasing in future scenarios up to 113 % in the northern zone and moving towards the mountains. This species conserves around 90 % of its niche in the future, and shows a reduction of 11.4 % in the severe climate change scenario. It is anticipated that Chile will experience an increase in the environmental suitability for Cx. pipiens moving from the Andes to the coastal zone throughout the country, mainly in the center-south. This will raise the risk of local virus transmission if the virus is introduced to the country via diverse routes.

In 2016, four clusters of local mosquitoborne Zika virus transmission were identified in Miami-Dade County, Florida, USA, generating “red zones” (areas into which pregnant women were advised against traveling). The Miami-Dade County Mosquito Control Division initiated intensive control activities, including property inspections, community education, and handheld sprayer applications of larvicides and adulticides. For the first time, the Mosquito Control Division used a combination of areawide ultralow-volume adulticide and low-volume larvicide spraying to effectively control Aedes aegypti mosquitoes, the primary Zika virus vector within the county. The number of mosquitoes rapidly decreased, and Zika virus transmission was interrupted within the red zones immediately after the combination of adulticide and larvicide spraying.

The purpose of the research is studying features of daily activity of different blood-sucking mosquito species from the southern taiga subareas, and aspen and birch forests of the Tyumen Region woodland and forest-steppe zone. Materials and methods. The researches were conducted in 2005–2015 in the south of the Tyumen Region in three natural environment and climatic areas (subareas), namely, the southern taiga, the aspen and birch forests, and the forest-steppe zone. The surveys were carried out in each of three subareas twice in the summertime, namely, in June and July. The census of biting mosquitoes was held using an entomological net with detachable sacs. An interval between the censuses held was 2 hours. The temperature, relative air humidity, wind velocity and precipitation were recorded simultaneously. In determining a species composition of the blood-sucking mosquito imago, special identification tables were applied; specific names were given in accordance with the current list of valid specific names. Results and discussion. Blood-sucking mosquito number in the south of the Tyumen Region is high within 24 hours. The maximum number and a peak in species diversity were observed at 11 p.m. in all-natural environment and climatic areas of the Region. In studying a 24-hour rhythm, attacks by 29 mosquito species of the Culicidae family, which belong to five genera, namely, Anopheles, Culiseta, Coquillettidia, Aedes and Culex were detected. In terms of temperature, they can roughly be divided into two groups. The first group (10 species) includes species that attack actively at 10 to 20°С, and the second group (19 species) includes species that attack actively at 10 to 30°С. High flight activity of mosquitoes can be observed at 12.6–26°С, relative air humidity of 54–99% and light intensity of 0–8600 lux. Given night temperatures are relatively high, the main factor that limits mosquito night activity is fog occurrence with air humidity up to 100%. One of the limiting factors for mosquitoes is strong wind; when wind velocity was 5 m/sec, attacks by few individual mosquitoes were only detected. The female mosquito activity is influenced by their overall number – the higher the mosquito number is, the harder they find a feeder and receive required blood meal.

Aquatain® is an alternative larvicide formulation to the currently used larvicides. Its efficacy can be assessed monitoring emerging adults with a floating device that was recently developed for use in catch basins. In this study, the efficacy of Aquatain in controlling Aedes albopictus and Culex pipiens complex was investigated by comparing the adults emerging from 25 treated catch basins with that of 25 control basins in northeastern Italy. Basins were monitored weekly for 9 times and the efficacy was evaluated using the Mann–Whitney U-test and calculating the inhibition of emergence at each sampling. Aquatain was effective in reducing the number of emerging mosquitoes for both species, but its duration was affected by rainfall. Intensive showers (>10 mm daily) seem to reduce the efficacy of the product, allowing an increase in emerging adults after about 2 wk. This finding suggests that climatic factors should be taken into account to decide the right time for reapplication of Aquatain during routine larval treatments.

Culex pipiens (Diptera: Culicidae) is one of the most prevalent mosquitoes particularly in the Al-Madinah Al-Munawwarah region, Kingdom of Saudi Arabia, transmitting numerous diseases such as arboviruses, avian malaria, elephantiasis, dirofilariasis, and encephalitis. Worldwide, Culex pipiens has developed resistance to numerous insecticides; therefore, considerable efforts have been done to introduce new mosquito control candidates. Due to their unique physical, biological, and eco-friendly properties, ionic liquids (ILs) have been recently considered as promising agents in controlling a variety of organisms. Six aminopyridinium-based ionic liquids (IL1–IL6) were assayed against eggs and pupae of C. pipiens. Percentages of non-hatched eggs, non-emerged pupae, the lethal concentrations (LC50 and LC90) of both C. pipiens eggs and pupae were recorded. after exposure, to different ILs. The effects of ILs against eggs and pupae were concentration and IL-dependant. The percentages of egg unhatchability were much higher than those of pupal mortality, as the percentage of egg unhatchability reached 99% after treatment with IL6 at 0.5 g/L, while the percentage of pupal mortality reached 40.8% after treatment with IL4 at 0.5 g/L. The LC50 and LC90 of ILs against pupae were much higher than those of ILs against eggs. Effects of ILs on Staphylococcus aureus (Bacillales: Staphylococcaceae) and Escherichia coli (Entrobacterales: Entrobacteriaceae) were also studied; some ILs showed a considerable effect on both bacteria species. This is the first study to show the ovicidal, pupicidal, and bactericidal effects of aminopyridinium-based ILs in controlling C. pipiens, S. aureus, and E. coli.

The bites of blood-feeding insects regularly induce sensitization to salivary proteins and cause local hypersensitivity reactions in over 90% of the population, representing either an IgE-mediated immediate wheal and flare reaction or a T cell-driven delayed papule. Long-lasting large local reactions and bullous reactions may cause significant discomfort and reduction in quality-of-life. Anaphylaxis is rarely reported though proven for several insects, above all mosquitoes, horse flies, and kissing bugs. Recently, salivary gland proteins have been thoroughly studied in some blood-feeding insect species, and several allergens have been identified. Interestingly, many of them belong to the same protein families as the well-known honeybee and wasp venom allergens (phospholipases, hyaluronidases, antigens 5, serine proteases) though sequence identities are mostly low. There is still insufficient evidence for the proposed cross-reactivity between salivary proteins from blood-feeding insects and Hymenoptera venom allergens.

Aedes aegypti is an invasive mosquito species and major vector of human arboviruses. A wide variety of control methods have been employed to combat mosquito populations. One of them is the sterile insect technique (SIT) that has recently attracted considerable research efforts due to its proven record of success and the absence of harmful environmental footprints. The efficiency and cost-effectiveness of SIT is significantly enhanced by male-only releases. For mosquito SIT, male-only releases are ideally needed since females bite, blood-feed and transmit the pathogens. Ae. aegypti genetic sexing strains (GSS) have recently become available and are based on eye colour mutations that were chosen as selectable markers. These genetic sexing strains were developed through classical genetics and it was shown to be subjected to genetic recombination, a phenomenon that is not suppressed in males as is the case in many Diptera. The genetic stability of these GSS was strengthened by the induction and isolation of radiation-induced inversions. In this study, we used the red eye mutation and the inversion Inv35 line of the Ae. aegypti red-eye GSS s and introgressed them in six different genomic backgrounds to develop GSS with the respective local genomic backgrounds. Our goal was to assess whether the recombination frequencies in the strains with and without the inversion are affected by the different genomic backgrounds. In all cases the recombination events were suppressed in all Inv35 GSS strains, thus indicating that the genomic background does not negatively affect the inversion result. Absence of any effect that could be ascribed to genetic differences, enables the introgression of the key elements of the GSS into the local genomic background prior to release to the target areas. Maintaining the local background increases the chances for successful matings between released males and wild females and addresses potential regulatory concerns regarding biosafety and biosecurity.

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.

In Colombia Aedes aegypti is present in 80% of the country up to 2,300 m; however, little is known of its genetic relations within a country context and, hence, within a broader context, for example, America. The aforementioned, herein, analyzed the gene flow within a context of the Americas, its directionality and genetic diversity of the mitochondrial lineages in the A. aegypti populations for Colombia. This called for the use of the sequences for A. aegypti available of the mitochondrial ND4 gene in the GenBank for Colombia and the American continent. No presence was found of nuclear mitochondrial pseudogenes (NUMTs) for Colombia. It is estimated that in Colombia the gene flow of the A. aegypti populations is occurring from the southeast and northeast toward the center of the country. In comparison with the mitochondrial sequences for America, the vector’s haplotypes in Colombia suggest connections between the populations of mosquitoes from the south with those from the north of the continent. The gene flow model at continental scale suggests bidirectional connections between the populations from the north of the continent with those from the south, while at South American scale it proposes the gene flow in all the directions with respect to the Colombian. The Colombian A. aegypti vector monitoring and control strategies must pay special attention to the vector’s points of entry into Colombia related with Peru, Venezuela, Brazil, Mexico, and North America to avoid the entry of populations with characteristics like resistance to insecticides or vector competition.

A Thesis for applying for the degree of Doctor of Philosophy in Applied Biology. Väitekiri filosoofiadoktori kraadi taotlemiseks rakendusbioloogia erialal. Mosquitoes are globally distributed insects that are familiar to most people. Thus far, 3 591 mosquito species have been described, but only a small number of these are medically important. Mosquitoes of both genders mainly feed on nectar and plant liquids, only the females of some species require a blood meal to reproduce. Mosquito bites are extremely uncomfortable for the victims and can contribute to the spread of various pathogens. Mosquitoes have been manly seen as a problem in tropical and subtropical regions, with countries like Estonia receiving little attention since the mid-20th century. This thesis is based on research concerning the genetic variation of the species Aedes communis, relationships between urban mosquitoes and weather factors as well as a summary of Estonian mosquito fauna. Specimens were collected from numerous sites in the country, with sweep nets as well as various insect traps. For the most part, individuals were identified based on morphological traits, but genetic methods were also used when needed. The analysis of three genetic markers of Aedes communis specimens lead to the discovery of an additional mitochondrial DNA lineage within the species. In fact, the newly discovered lineage was found to be more similar to the genetic sequences of some North-American species than to other Aedes communis. Although the reason for this genetic variation is not known, it shows that species identifications should not be based on only mitochondrial markers. It is well known that cities are warmer and somewhat drier than the surrounding areas. Higher temperatures are usually favourable for mosquitoes, but they are in danger of drying out in low humidity. Research in the town of Tartu indicated, that as air temperature rises, the number of active mosquitoes lowers along with the relative humidity. Mosquitoes were also less active when it was windy and insect abundance was influenced by springtime floods. The updated Estonian mosquito checklist came to include 34 species, which is four more species than was on the first list published in 1957. Seven additional species are suspected to be present, but require more research. Pistesääsklased on ülemaailmse levikuga putukad, kes on tuttavad ka Eesti inimestele. Maailmas on tänaseks kirjeldatud 3 591 pistesääsklaste liiki, kuid vaid väike osa neist on meditsiiniliselt olulised. Pistesääsklased toituvad põhiliselt nektarist ja taimemahladest, vaid emased isendid vajavad munade tootmiseks verd. Emaste pistesääsklaste torked on ohvritele äärmiselt häirivad, kuid läbi selle võivad levida ka mitmesugused haigustekitajad. Pistesääsklaseid on pikka aega peetud põhilistelt troopiliste ja lähistroopiliste alade probleemiks, mistõttu jäi nende uurimine Eestis pärast eelmise sajandi keskpaika pikaks ajaks soiku. Doktoritöös uuriti Põhja- ja Baltimaades äärmiselt arvuka hariliku metsasääse (Aedes communis) geneetilist mitmekesisust, Tartu linna pistesääsklaseid mõjutavaid klimaatilisi tegureid ning uuendati Eesti liikide nimekirja. Selleks koguti pistesääsklaseid erinevatest Eesti paikadest, kasutades nii putukavõrku kui mitmesuguseid püüniseid. Isendid tuvastati peamiselt morfoloogiliste tunnuste põhjal, kuid vajadusel kasutati ka DNA põhiseid meetodeid. Harilike metsasääskede kolme DNA markeri analüüs näitas, et antud liik peidab endas kahte märkimisväärselt erinevat mitokondriaalse DNA liini, samas kui tuuma DNAs sarnast lahknevust ei esine. Seejuures oli avastatud mitokondriaalse DNA liin sarnasem Põhja-Ameerika lähiliikide geneetilisele materjalile kui liigikaaslaste tüüpilistele sekventsidele. Kuigi sellise eristumise põhjus pole teada, näitab see ilmekalt, et liikide määramisel ja kirjeldamisel ei saa lähtuda vaid mitokondriaalse DNA markeritest. On teada, et linnad on üldiselt soojemad ja mõnevõrra kuivemad kui ümbritsevad alad. Soojus on pistesääsklastele harilikult soodne, kuid nende vastsed vajavad veekeskkonda ning valmikud võivad kergesti läbi kuivada. Kolm aastat kestnud uurimus näitas, et temperatuuri tõustes vähenes nii õhuniiskus kui aktiivsete pistesääsklaste arv Tartu linnas. Etteaimatavalt lendas verd imevaid putukaid vähem ka tuulisema ilma korral. Samuti mõjutas pistesääsklaste arvukust kevadine üleujutusvesi. Uus Eesti pistesääsklaste nimekiri sisaldab 34 liiki, mis on neli liiki rohkem kui oli 1957. aasta nimekirjas. Lahtiseks jäi veel seitsme liigi staatus, mis võivad siinkandis esineda, kui mille kohalolu ei ole olnud võimalik seniste püükidega tõestada. Publication of this dissertation has been supported by the Estonian University of Life Sciences.

Long non-coding RNAs (lncRNAs) lack coding capacity and mounting evidence suggests that they have a regulatory role in diverse organisms. Most knowledge about lncRNAs comes from studies on vertebrates, including a structural association between lncRNAs and transposable elements (TEs). TE sequences are genomic parasites found in all branches of life and are particularly active and abundant in insect genomes. Here we investigate the contribution of TEs to lncRNA biogenesis in Aedes albopictus and Culex quinquefasciatus. We found that a large fraction of lncRNA loci co-occurs with TE loci in both species. Around 40% of A. albopictus and 52% of C. quinquefasciatus lncRNAs show some association with TEs. Most of the lncRNA/TE associations are represented by TE-derived sequences that are expressed as one or all exons of lncRNAs, including five lncRNAs that seem to influence immune-related genes involved in antiviral response. The contribution of TEs to lncRNAs also varies among the different types of TEs. The Gypsi superfamily is particularly enriched in lncRNAs sequences. In sum, this study demonstrates that transposable elements substantially contribute to lncRNAs biogenesis in A. albopictus and C. quinquefasciatus and may have an impact on regulatory modulation in these species.

Australia experienced its largest recorded outbreak of Ross River virus (RRV) during the 2014–15 reporting year, comprising >10,000 reported cases. We investigated epidemiologic, entomologic, and virologic factors that potentially contributed to the scale of the outbreak in Queensland, the state with the highest number of notifications (6,371). Spatial analysis of human cases showed that notifications were geographically widespread. In Brisbane, human case notifications and virus detections in mosquitoes occurred across inland and coastal locations. Viral sequence data demonstrated 2 RRV lineages (northeastern genotypes I and II) were circulating, and a new strain containing 3 unique amino acid changes in the envelope 2 protein was identified. Longitudinal mosquito collections demonstrated unusually high relative abundance of Culex annulirostris and Aedes procax mosquitoes, attributable to extensive freshwater larval habitats caused by early and persistent rainfall during the reporting year. Increased prevalence of these mosquitoes probably contributed to the scale of this outbreak.