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Bio-degradable and eco-friendly essential oils (EOs) extracted from Mentha longifolia, Salsola imbricata, Erigeron bonariensis, E. canadensis, Ailanthus altissima, and Zanthoxylum armatum were investigated for their repellent and larvicidal potential against Aedes aegypti mosquitoes. The EOs of M. longifolia, S. imbricata, E. bonariensis, E. canadensis, A. altissima, and Z. armatum exhibited 99.0%, 96.8%, 40.2%, 41.7%, 29.1%, and 13.2% repellency against mosquitoes at a tested dose of 33.3 μg/cm2, respectively. In time span bioassays, the EOs of M. longifolia, S. imbricata, E. bonariensis, and E. canadensis showed more than 40% repellency for 60 min at a tested dose of 330 μg/cm2. Larvicidal bioassays revealed that larvae of Ae. aegypti were the most susceptible to M. longifolia (LC50, 39.3 mg/L), E. bonariensis (LC50, 26.0 mg/L), E. canadensis (LC50, 35.7 mg/L), and Z. armatum (LC50, 35.9 mg/L) EOs upon 48 h exposure. The most abundant constituents in the EOs of M. longifolia, S. imbricata, E. bonariensis, E. canadensis and A. altissima were piperitone oxide (45.5%), carvone (39.9%), matricaria ester (43.1%), (31.7%) and eugenol (24.4%), respectively. Our study demonstrates that EOs of M. longifolia, S. imbricata, E. bonariensis, and E. canadensis might be used to control Ae. aegypti mosquitoes without harming humans or the environment.

Background Wolbachia pipientis is an endosymbiont bacterium that induces cytoplasmic incompatibility and inhibits arboviral replication in mosquitoes. This study aimed to assess Wolbachia prevalence and genetic diversity in different mosquito species from Cape Verde. Methods Mosquitoes were collected on six islands of Cape Verde and identified to species using morphological keys and PCR-based assays. Wolbachia was detected by amplifying a fragment of the surface protein gene (wsp). Multilocus sequence typing (MLST) was performed with five housekeeping genes (coxA, gatB, ftsZ, hcpA, and fbpA) and the wsp hypervariable region (HVR) for strain identification. Identification of wPip groups (wPip-I to wPip-V) was performed using PCR–restriction fragment length polymorphism (RFLP) assay on the ankyrin domain gene pk1. Results Nine mosquito species were collected, including the major vectors Aedes aegypti, Anopheles arabiensis, Culex pipiens sensu stricto, and Culex quinquefasciatus. Wolbachia was only detected in Cx. pipiens s.s. (100% prevalence), Cx. quinquefasciatus (98.3%), Cx. pipiens/quinquefasciatus hybrids (100%), and Culex tigripes (100%). Based on the results of MLST and wsp hypervariable region typing, Wolbachia from the Cx. pipiens complex was assigned to sequence type 9, wPip clade, and supergroup B. PCR/RFLP analysis revealed three wPip groups in Cape Verde, namely wPip-II, wPip-III, and wPip-IV. wPip-IV was the most prevalent, while wPip-II and wPip-III were found only on Maio and Fogo islands. Wolbachia detected in Cx. tigripes belongs to supergroup B, with no attributed MLST profile, indicating a new strain of Wolbachia in this mosquito species. Conclusions A high prevalence and diversity of Wolbachia was found in species from the Cx. pipiens complex. This diversity may be related to the mosquito's colonization history on the Cape Verde islands. To the best of our knowledge, this is the first study to detect Wolbachia in Cx. tigripes, which may provide an additional opportunity for biocontrol initiatives. Graphical Abstract

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

Although Malaysia is considered free of human malaria, there has been a growing number of Plasmodium knowlesi cases. This alarming trend highlighted the need for our understanding of this parasite and its associated vectors, especially considering the role of genetic diversity in the adaptation and evolution among vectors in endemic areas, which is currently a significant knowledge gap in their fundamental biology. Thus, this study aimed to investigate the genetic diversity of Anopheles balabacensis, Anopheles cracens, Anopheles introlatus, and Anopheles latens—the vectors for P. knowlesi malaria in Malaysia. Based on cytochrome c oxidase 1 (CO1) and internal transcribed spacer 2 (ITS2) markers, the genealogic networks of An. latens showed a separation of the haplotypes between Peninsular Malaysia and Malaysia Borneo, forming two distinct clusters. Additionally, the genetic distances between these clusters were high (2.3–5.2% for CO1) and (2.3–4.7% for ITS2), indicating the likely presence of two distinct species or cryptic species within An. latens. In contrast, no distinct clusters were observed in An. cracens, An. balabacensis, or An. introlatus, implying a lack of pronounced genetic differentiation among their populations. It is worth noting that there were varying levels of polymorphism observed across the different subpopulations, highlighting some levels of genetic variation within these mosquito species. Nevertheless, further analyses revealed that all four species have undergone demographic expansion, suggesting population growth and potential range expansion for these vectors in this region.

Bio-insecticidal research has focused on long-term vector control using essential oils (EOs). This study examined the larvicidal, oviposition-deterrent, and repellent properties of five medicinal herb-based EO formulations (EOFs) on mosquitoes that are vectors of dengue, filariasis, and malaria. EOFs were significantly more toxic to the larvae and pupae of Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti with LC50 = 9.23, 12.85, and 14.46 ppm, as well with 10.22, 11.39, and 12.81 ppm, with oviposition active indexes of −0.84, −0.95, and −0.92, respectively. Oviposition-deterrent repellence was found in 91.39%, 94.83%, and 96.09%. EOs and N, N-Diethyl-3-methylbenzamide (DEET) were prepared at various concentrations for time duration repellent bioassays (6.25–100 ppm). Ae. aegypti, An. stephensi, and Cx. quinquefasciatus were monitored for 300, 270, and 180 min, respectively. At 100 ppm, EOs and DEET had comparable repellence in terms of test durations. EOF’s primary components d-limonene (12.9%), 2,6-octadienal, 3,7-dimethyl, (Z) (12.2%), acetic acid, phenylmethyl ester (19.6%), verbenol (7.6%), and benzyl benzoate (17.4%) may be combined to make a mosquito larvicidal and repellant equivalent to synthetic repellent lotions. In the molecular dynamics simulations, limonene (−6.1 kcal/mol) and benzyl benzoate (−7.5 kcal/mol) had a positive chemical association with DEET (−6.3 kcal/mol) and interacted with the OBP binding pocket with high affinity and stability. This research will help local herbal product manufacturers and the cosmetics industry in developing 100% herbal insect repellent products to combat mosquito-borne diseases, including dengue, malaria, and filariasis.

Vector-borne diseases transmitted through the bites of hematophagous arthropods, such as mosquitoes, continue to be a significant threat to human health globally. Transmission of disease by biting arthropod vectors includes interactions between (1) saliva expectorated by a vector during blood meal acquisition from a human host, (2) the transmitted vector-borne pathogens, and (3) host cells present at the skin bite site. Currently, the investigation of bite-site biology is challenged by the lack of model 3D human skin tissues for in vitro analyses. To help fill this gap, we have used a tissue engineering approach to develop new stylized human dermal microvascular bed tissue approximates—complete with warm blood—built with 3D capillary alginate gel (Capgel) biomaterial scaffolds. These engineered tissues, termed a Biologic Interfacial Tissue-Engineered System (BITES), were cellularized with either human dermal fibroblasts (HDFs) or human umbilical vein endothelial cells (HUVECs). Both cell types formed tubular microvessel-like tissue structures of oriented cells (82% and 54% for HDFs and HUVECs, respectively) lining the unique Capgel parallel capillary microstructures. Female Aedes (Ae.) aegypti mosquitoes, a prototypic hematophagous biting vector arthropod, swarmed, bit, and probed blood-loaded HDF BITES microvessel bed tissues that were warmed (34–37 °C), acquiring blood meals in 151 ± 46 s on average, with some ingesting ≳4 µL or more of blood. Further, these tissue-engineered constructs could be cultured for at least three (3) days following blood meal acquisitions. Altogether, these studies serve as a powerful proof-of-concept demonstration of the innovative BITES platform and indicate its potential for the future investigation of arthropod bite-site cellular and molecular biology.

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.

Females of the genus Mansonia feed on the blood of humans, livestock, and other vertebrates to develop their eggs. The females’ biting behavior may cause severe disturbance to blood hosts, with a negative impact on public health and economics. Certain species have been identified as potential or effective disease vectors. The accurate species identification of field-collected specimens is of paramount importance for the success of monitoring and control strategies. Mansonia (Mansonia) morphological species boundaries are blurred by patterns of intraspecific heteromorphism and interspecific isomorphism. DNA barcodes can help to solve taxonomic controversies, especially if combined with other molecular tools. We used cytochrome c oxidase subunit I (COI) gene 5′ end (DNA barcode) sequences to identify 327 field-collected specimens of Mansonia (Mansonia) spp. The sampling encompassed males and females collected from three Brazilian regions and previously assigned to species based on their morphological characteristics. Eleven GenBank and BOLD sequences were added to the DNA barcode analyses. Initial morphospecies assignments were mostly corroborated by the results of five clustering methods based on Kimura two-parameter distance and maximum likelihood phylogeny. Five to eight molecular operational taxonomic units may represent taxonomically unknown species. The first DNA barcode records for Mansonia fonsecai, Mansonia iguassuensis, and Mansonia pseudotitillans are presented.

Цель исследования. Проанализировать и систематизировать эпидемиологическую напряженность по малярии и лихорадке Западного Нила в Астраханской области во временном промежутке между 2005 и 2022 гг. Отследить тенденции к улучшению или ухудшению ситуации в регионе.Материалы и методы. Исследовательская деятельность проводилась сразу на нескольких базах г. Астрахань: эпидемиологического отдела, вирусологической и паразитологической лабораторий ФБУЗ «Центр гигиены и эпидемиологии в Астраханской области», а также кафедры инфекционных болезней и эпидемиологии ФГБОУ ВО «Астраханский государственный медицинский университет» Минздрава России.Результаты исследования. За период с 2005 по 2022 гг. на территории Астраханской области было выявлено 460 случаев лихорадки Западного Нила, со средним многолетним показателем заболеваемости 2,6 на 100 тыс. населения. В ходе проанализированной информации можно выделить пики заболеваемости, которые приходятся на 2005 год (73 случая), 2012 год (72 случая), 2013 год (70 случаев), 2019 год (81 случай). За период с 2005 года по 2022 по Астраханской области было зарегистрировано 25 случаев малярии. В 2017 году, в г. Астрахань был обнаружен интересный случай смешанной малярии (P. ovale + P. Falciparum) у обучающегося АГТУ. Преобладание случаев малярии составило 30% в 2005 году; с 2009 по 2013 год в Астраханской области не было случаев малярии, но с 2014 года они регистрируются вновь. В настоящее время малярия регистрируется достаточно редко. Так, в 2019 году был обнаружен единичный случай малярии, в 2020 году 2 случая, в 2021 году не было зарегистрировано ни одного эпизода. За последний год на территории Астраханской области зарегистрировано 2 случая малярии.Выводы. В течение исследуемого периода 2005-2022 гг. заболеваемость лихорадкой Западного Нила возросла во всех регионах Астраханской области, составив в среднем 2,6 случая на 100 тыс. населения, а заболеваемость завозной малярией снизилась. ЛЗН и малярия в Астраханской области характеризуются выраженной сезонностью с лета до осени. Пик заболеваемости приходится на период с июня по октябрь, с преобладанием 48,8% в августе (лихорадка Западного Нила) и 25% в июле (малярия). Случаи заболевания людей были зарегистрированы во всех возрастных группах (дети и взрослые)., Objective of the study. To analyse and systematize the epidemiological situation of malaria and West Nile fever in Astrakhan Oblast between 2005 and 2022. To trace trends of improvement or deterioration of the situation in the region.Materials and methods. The research was carried out at several sites in Astrakhan: the epidemiology department, virology and parasitology laboratories of the Centre for Hygiene and Epidemiology in the Astrakhan Region, and the Department of Infectious Diseases and Epidemiology of the Astrakhan State Medical University, Ministry of Health of Russia.Results of the study. Between 2005 and 2022, 460 cases of West Nile fever were detected in Astrakhan Oblast, with a multi-year average incidence rate of 2.6 per 100,000 population. The analysed information shows that morbidity peaks in 2005 (73 cases), 2012 (72 cases), 2013 (70 cases), 2019 (81 cases). From 2005 to 2022, 25 cases of malaria were registered in Astrakhan Oblast. In 2017, an interesting case of mixed malaria (P. ovale + P. Falciparum) was detected in an Astrakhan student of the ASTU. The prevalence of malaria cases was 30% in 2005; from 2009 to 2013 there were no malaria cases in Astrakhan Oblast, but since 2014 they have been registered again. At present, malaria is registered rather infrequently. For example, in 2019 a single case of malaria was detected, in 2020 2 cases, in 2021 no episodes were registered. In the last year, 2 cases of malaria have been registered in Astrakhan Oblast.Conclusions. The incidence of West Nile fever increased in all Astrakhan Oblast regions during the investigated period 2005–2022 averaging 2.6 cases per 100,000 people, and the incidence of imported malaria decreased. VHF and malaria in Astrakhan Oblast are characterized by a pronounced seasonality from summer to autumn. Morbidity peaks between June and October, with a prevalence of 48.8% in August (West Nile fever) and 25% in July (malaria). Human cases were reported in all age groups (children and adults)., Международный научно-исследовательский журнал, Выпуск 4 (130) 2023

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.

We assessed the effect of the entomopathogenic fungus Metarhizium anisopliae against Aedes aegypti. Conidia of M. anisopliae strains CG 489, CG 153, and IBCB 481 were grown in Adamek medium under different conditions to improve blastospore production. Mosquito larvae were exposed to blastospores or conidia of the three fungal strains at 1 × 107 propagules mL−1. M. anisopliae IBCB 481 and CG 153 reduced larval survival by 100%, whereas CG 489 decreased survival by about 50%. Blastospores of M. anisopliae IBCB 481 had better results in lowering larval survival. M. anisopliae CG 489 and CG 153 reduced larval survival similarly. For histopathology (HP) and scanning electron microscopy (SEM), larvae were exposed to M. anisopliae CG 153 for 24 h or 48 h. SEM confirmed the presence of fungi in the digestive tract, while HP confirmed that propagules reached the hemocoel via the midgut, damaged the peritrophic matrix, caused rupture and atrophy of the intestinal mucosa, caused cytoplasmic disorganization of the enterocytes, and degraded the brush border. Furthermore, we report for the first time the potential of M. anisopliae IBCB 481 to kill Ae. aegypti larvae and methods to improve the production of blastospores.

Mosquito-borne diseases account for around one million deaths annually. There is a constant need for novel intervention mechanisms to mitigate transmission, especially as current insecticidal methods become less effective with the rise of insecticide resistance among mosquito populations. Previously, we used a near infra-red tracking system to describe the behaviour of mosquitoes at a human-occupied bed net, work that eventually led to an entirely novel bed net design. Advancing that approach, here we report on the use of trajectory analysis of a mosquito flight, using machine learning methods. This largely unexplored application has significant potential for providing useful insights into the behaviour of mosquitoes and other insects. In this work, a novel methodology applies anomaly detection to distinguish male mosquito tracks from females and couples. The proposed pipeline uses new feature engineering techniques and splits each track into segments such that detailed flight behaviour differences influence the classifier rather than the experimental constraints such as the field of view of the tracking system. Each segment is individually classified and the outcomes are combined to classify whole tracks. By interpreting the model using SHAP values, the features of flight that contribute to the differences between sexes are found and are explained by expert opinion. This methodology was tested using 3D tracks generated from mosquito mating swarms in the field and obtained a balanced accuracy of 64.5% and an ROC AUC score of 68.4%. Such a system can be used in a wide variety of trajectory domains to detect and analyse the behaviours of different classes, e.g., sex, strain, and species. The results of this study can support genetic mosquito control interventions for which mating represents a key event for their success.

Aedes (Stegomyia) albopictus (Skuse, 1854) was reported in Brazil for the first time in 1986 and has shown marked expansion throughout the Brazilian territory. During a routine activity to control dengue fever conducted by the Division of Entomology of the Municipal Health Department in Rio Branco city, adults and immatures of Culicidae were collected in a peri-urban area. The identified Culicidae forms indicated that they belonged to the species Ae. albopictus. This is the first official record of the presence of Ae. albopictus in the Acre State, confirming its current presence in all Brazilian states.

Yellow fever (YF) is an emerging and re-emerging arboviral disease transmitted through the bites of infected Aedes mosquitoes, primarily in the genus Aedes. Several outbreaks of yellow fever have been documented in southern Ethiopia. Four outbreaks have been documented since 2012, suggesting that southern Ethiopia is prone to YF outbreaks. Understanding the transmission cycle is pivotal to managing arboviral disease outbreaks, and the aims of the present study were to investigate the mosquito species that most likely contributed to the recent YF outbreaks and to study their behaviors. Therefore, the present study aimed to evaluate which species of Aedes mosquitoes contribute to the YF virus transmission, the outbreaks that have occurred and their behaviors (biting and resting) in the region. Two districts were selected on the basis of recent YF outbreak history. A longitudinal entomological survey was conducted to collect adult mosquitoes by using human landing catches (HLC), mechanical mouth aspirators and pyrethrum sprays. Collections were conducted twice a month for six months, from February 2019 to July 2020. The mosquitoes were identified by species by using morphological keys and molecular techniques. A total of 1689 mosquitoes were collected, of which 93.7% (1582/1689) were members of the genus Aedes and 6.3% (107/1689) of the genus Culex. A total of 58.7% (991/1689) of the mosquitoes were captured in the Ofa District and 41.3% (698/1689) from the Boko Dawula District. The largest number of mosquitoes, 97.9% (1653/1689), were collected during the wet season. A total of 1582 members of the Aedes simpsoni complex were collected, where 57.7% (913/1582) were from the Ofa District and 42.3% (669/1582) were from the Boko Dawula District. Molecular identification showed that members of the Aedes simpsoni complex accounted for 99.5% (404/406), while Aedes aegypti, detected only in the Ofa District, accounted for only 0.5% (2/406). The mosquitoes were pooled and tested for YFV, dengue virus (DENV, serotype 1–4) and chikungunya virus (CHKV) by using qPCR. None of the 934 Aedes simpsoni tested were positive for any arboviruses. The human-biting activities of Ae. simpsoni complex were peaked between 8:00–9:00 and 16:00–17:00, mostly outdoors, both within the villages and the forests. The largest numbers of Aedes simpsoni complex resting mosquitoes were collected from the leaves of the Abyssinian banana, Ensete ventricosum, suggesting that they are the preferred resting places. Although the tested Ae. simpsoni complex was negative for arboviruses; the morning and afternoon activities of the species complex coincide with peak human outdoor activities in these areas and may therefore pose the highest risk of transmitting YFV to humans. The extremely low abundance of Aedes aegypti suggests a minor role in arbovirus transmission in southern Ethiopia. It is of great importance that expanded surveillance activities of arboviruses to include reservoir hosts and sylvatic vectors to the chances of devising and implementing effective control measures.

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.

Cache Valley virus (CVV) is a mosquitoborne virus that infects livestock and humans. We report results of surveillance for CVV in New York, USA, during 2000-2016; full-genome analysis of selected CVV isolates from sheep, horse, humans, and mosquitoes from New York and Canada; and phenotypic characterization of selected strains. We calculated infection rates by using the maximum-likelihood estimation method by year, region, month, and mosquito species. The highest maximum-likelihood estimations were for Anopheles spp. mosquitoes. Our phylogenetic analysis identified 2 lineages and found evidence of segment reassortment. Furthermore, our data suggest displacement of CVV lineage 1 by lineage 2 in New York and Canada. Finally, we showed increased vector competence of An. quadrimaculatus mosquitoes for lineage 2 strains of CVV compared with lineage 1 strains.

BackgroundVector-borne diseases are a major burden to public health. Controlling mosquitoes is considered the most effective way to prevent vector-borne disease transmission. Mosquito surveillance is a core component of integrated vector management, as surveillance programs are often the cornerstone for the development of mosquito control operations. Two traps are the most commonly used for the surveillance of adult mosquitoes: Centers for Disease Control and Prevention miniature light trap (CDC light trap) and BG-Sentinel trap (BioGents, Regensburg, Germany). However, despite the importance of the BG-Sentinel trap in surveillance programs in the United States, especially in the Southern states, its effectiveness in consistently and reliably collecting mosquitoes in rural and natural areas is still unknown. We hypothesized that BG-Sentinel and CDC light traps would be more attractive to specific mosquito species present in rural and natural areas. Therefore, our objective was to compare the relative abundance, species richness, and community composition of mosquitoes collected in natural and rural areas by BG-Sentinel and CDC light traps.MethodsMosquitoes were collected from October 2020 to March 2021 using BG-Sentinel and CDC light traps baited with dry ice, totaling 105 trap-nights.ResultsThe BG-Sentinel traps collected 195,115 mosquitoes comprising 23 species from eight genera, and the CDC light traps collected 188,594 mosquitoes comprising 23 species from eight genera. The results from the permutational multivariate analysis of variance (PERMANOVA) and generalized estimating equation model for repeated measures indicate the BG-Sentinel and CDC light traps had similar sampling power.ConclusionEven though BG-Sentinel traps had a slightly better performance, the difference was not statistically significant indicating that both traps are suitable to be used in mosquito surveillance in rural and natural areas.Graphical Abstract

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.

Dissertação de Mestrado Integrado em Medicina Veterinária, na área científica de Sanidade Animal A globalização e as alterações climáticas influenciam o aparecimento e ressurgimento de doenças transmitidas por mosquitos. Na Europa, seis espécies de mosquitos foram demonstradas como vetores competentes para o vírus do Nilo Ocidental (VNO), nomeadamente Culex pipiens, Cx. modestus, Cx. perexiguus, Cx. torrentium, Aedes albopictus, e Ae. detritus. Culex pipiens é considerado o principal vetor de transmissão do VNO no nosso país. Em Portugal, bem como se verifica noutros países, parecem estar presentes as condições ecológicas essenciais à circulação e manutenção do VNO no ecossistema. No período de outubro de 2021 a fevereiro de 2022, no Centro de Estudos e Recuperação de Animais Selvagens de Castelo Branco (CERAS), foram instaladas duas armadilhas luminosas miniatura CDC, utilizando dióxido de carbono (CO2) como atrativo, para a captura de mosquitos. Utilizou-se também um aspirador de insetos portátil, para captura de mosquitos em instalações de animais selvagens e em contacto direto com o corpo dos animais. Complementarmente, foram obtidos dados acerca da temperatura do ar, humidade relativa e quantidade de precipitação, através do Instituto Português do Mar e da Atmosfera (IPMA), para posterior interpretação juntamente com os resultados obtidos. No presente estudo foram capturados, através das armadilhas, 70 mosquitos, não tendo sido capturado nenhum mosquito utilizando o aspirador. Capturaram-se, pelo menos, cinco espécies diferentes incluindo Anopheles maculipennis s.l., Culex pipiens, Culex theileri, Culiseta annulata e Culiseta longiareolata, dois mosquitos identificados como Aedes spp. e dois identificados como Anopheles spp.. Na totalidade da amostra verificou-se em maior quantidade a espécie Culex pipiens e observaram-se 53% (37/70) de machos e 47% (33/70) de fêmeas. Capturaram-se três fêmeas com abdómen engorgitado em outubro, novembro e mesmo no inverno, em janeiro. A realização do estudo neste período permitiu englobar os meses de outubro e novembro, em que ainda se verifica atividade de mosquitos, e os meses de dezembro, janeiro e fevereiro, permitindo realizar um estudo preliminar da atividade dos mosquitos no período de overwintering ABSTRACT - STUDY OF POTENTIAL INSECT VECTORS OF INFECTIOUS AGENTS IN THE ACTIVITY AREA OF THE WILDLIFE REHABILITATION CENTER OF CASTELO BRANCO - Globalization and climate change influence the emergence and resurgence of mosquito-borne diseases. In Europe, six mosquito species have been shown to be competent vectors for West Nile vírus (WNV), namely Culex pipiens, Cx. modestus, Cx. perexiguus, Cx. torrentium, Aedes albopictus, and Ae. detritus. Culex pipiens is considered to be the main vector for WNV transmission in this country. In Portugal, as well as in some other countries, the ecological conditions essential for the circulation and maintenance of the WNV in the ecosystem seem to be present. During the period from October 2021 to February 2022, at the Wildlife Rehabilitation Center of Castelo Branco, two miniature CDC light traps were placed, using carbon dioxide (CO2) as an attractant, to capture mosquitoes. A portable insect vacuum was also used to capture mosquitoes in wild animal enclosures and on direct contact with the animals. In addition, data on air temperature, relative humidity and rainfall amount were obtained from the Instituto Português do Mar e da Atmosfera (IPMA), for further interpretation along with the results obtained. During the study, 70 mosquitoes were captured by the traps, and no mosquitoes were captured using the vacuum. At least five different species were captured including Anopheles maculipennis s.l., Culex pipiens, Culex theileri, Culiseta annulata and Culiseta longiareolata, two mosquitoes identified as Aedes spp. and two identified as Anopheles spp. In the entire sample, the species Culex pipiens was found in higher quantities and were detected 53% (37/70) of males and 47% (33/70) of females. Three females with engorged abdomens were captured in October, November and even in winter, in January. This study enabled us to comprise the months of October and November, when mosquitoes are still active, and the months of December, January and February, allowing a preliminary study of overwintering mosquitoes N/A

The prevalence and distribution of African alphaviruses such as chikungunya have increased in recent years. Therefore, a better understanding of the local distribution of alphaviruses in vectors across the African continent is important. Here, entomological surveillance was performed from 2014 to 2018 at selected sites in north-eastern parts of South Africa where alphaviruses have been identified during outbreaks in humans and animals in the past. Mosquitoes were collected using a net, CDC-light, and BG-traps. An alphavirus genus-specific nested RT-PCR was used for screening, and positive pools were confirmed by sequencing and phylogenetic analysis. We collected 64,603 mosquitoes from 11 genera, of which 39,035 females were tested. Overall, 1462 mosquito pools were tested, of which 21 were positive for alphaviruses. Sindbis (61.9%, N = 13) and Middelburg (28.6%, N = 6) viruses were the most prevalent. Ndumu virus was detected in two pools (9.5%, N = 2). No chikungunya positive pools were identified. Arboviral activity was concentrated in peri-urban, rural, and conservation areas. A range of Culicidae species, including Culex univittatus, Cx. pipiens s.l., Aedes durbanensis, and the Ae. dentatus group, were identified as potential vectors. These findings confirm the active circulation and distribution of alphaviruses in regions where human or animal infections were identified in South Africa. publishersversion published

A Europa, l'amenaça del ressorgiment i introducció de malalties transmeses per mosquits, com la malària i la febre de la vall del Rift, ha despertat un nou interès en l'estudi del microbioma associat amb mosquits autòctons per a una millor comprensió de les interaccions mosquit-patogen amb la finalitat de desenvolupar eines de vigilància vectorial i control ecològicament més adequades - En conseqüència, la tesi present es va enfocar en i) explorar la microbiota de l'Anopheles atroparvus, ii) avaluar la influencia de flavivirus insecto-específic en la competència vectorial del Culex pipiens i de l'Aedes vexans d' Europa per a la transmissió de RVFV, i iii) Aplicar metagenòmica a targetes FTA com a nou mètode per a la detecció de virus i vigilància d'arbovirus. Al primer capítol, es va establir una colònia de laboratori d' An. atroparvus del Delta de l' Ebre i es va actualitzar el seu protocol de cria. El seqüènciament del gen bacterià 1S rRNA va mostrar que l'ambient de cria, fisiologia i hàbits de farratge va influir en la microbiota tant de mosquits de camp com de laboratori. Addicionalment, els anàlisis de diversitat van mostrar variació entre els diferents estadis de desenvolupament silvestres i un declivi de la diversitat en el grup de femelles de la desena generació de laboratori F10, tot i això, van conservar una fracció significativa de la microbiota de les femelles silvestres. Finalment, proteobactèries Gram-negatives van predominar en la microbiota de l' An. atroparvus, entre les quals Pseudomonas, Asaia i Serratia van ser identificades com a candidates potencials per al control vectorial local. Per avaluar la influencia de ISFVs en la competència vectorial enfront de la transmissió de RVFV (Capítol 2), primer es va estudiar la infecció de Culex flavivirus (CxFV) a Cx. Pipiens a través d'exposició oral i inoculació intratoràcica. CxFV va infectar a Cx. Pipiens després d'inoculacions intratoràciques però no a través de l'exposició oral. Posteriorment, els assajos de competència vectorial enfront de RVFV es van realitzar en co-infecció amb CxFV i un flavivirus de mosquit de circulació natural, respectivament, en Cx. pipiens i Ae. vexans. Ambdues poblacions locals van mostrar ser competents per a RVFV després d'exposició oral. Per altra banda, ni CxFV ni RVFV van interferir en la seva respectiva infecció, mentre que el flavivirus de mosquit de circulació natural va modular la susceptibilitat d'infecció amb RVFV en Ae. vexans, suggerint el seu potencial ús com agent biològic per a la prevenció de la transmissió de RVFV. Finalment, per a avaluar noves alternatives per a la detecció de virus circulants i vigilància d'arbovirus (Capítol 3), targetes FTA amb esquer de mel van ser exposades a mosquits capturats en el camp durant jornades de vigilància entomològica per a la seva posterior anàlisi mitjançant seqüenciació de nova generació. Virus associats a artròpodes i plantes van ser identificats en les FTAs i es van obtenir genomes virals gairebé complets, el que suggereix una bona preservació d' ARN viral. Per a confirmar la presència de virus associats amb mosquits en els espècimens capturats, els pools de mosquits van ser analitzats utilitzant PCR de transcripció reversa i primers espècie-específics dissenyats a partir de les seqüències obtingudes de les FTAs. Virus relacionats amb Alphamesonivirus, Quaranjavirus i Bunyavirales no classificats van ser detectats en mosquits de Catalunya constituent el primer registre de distribució d'aquests virus en mosquits europeus. La detecció d' ISVs a la saliva de mosquits de forma silvestre demostra la viabilitat d'aquest mètode per a fer monitoreig de la fracció transmissible del viroma de mosquits i a seva utilitat en la vigilància d'arbovirus. En Europa, la amenaza del resurgimiento e introducción de enfermedades transmitidas por mosquitos, como la malaria y la fiebre del Valle de Rift, ha despertado un nuevo interés en el estudio del microbioma asociado con mosquitos autóctonos para un mejor entendimiento de las interacciones mosquito-patógeno con el fin de desarrollar herramientas de vigilancia vectorial y control ecológicamente más adecuadas. Consecuentemente, la presente tesis se enfocó en: i) explorar la microbiota de Anopheles atroparvus, ii) evaluar la influencia de flavivirus insecto-específico en la competencia vectorial de Culex pipiens y Aedes vexans de Europa para la transmisión de RVFV, y iii) Aplicar metagenómica en tarjetas FTA como un nuevo método para la detección de virus y vigilancia de arbovirus. En el primer capítulo, se estableció una colonia de laboratorio de An. atroparvus del Delta del Ebro y se actualizó su protocolo de cría. El secuenciamiento del gen bacteriano 16S rRNA mostró que el ambiente de cría, fisiología y hábitos de forrajeo influyeron en la microbiota de mosquitos tanto de campo como de laboratorio. Los análisis de diversidad mostraron variación entre los diferentes estadios de desarrollo silvestres y un declive de diversidad en hembras de la décima generación de laboratorio, sin embargo, una fracción significativa de la microbiota de hembras silvestres fue conservada. Finalmente, proteobacterias Gram-negativas predominaron en la microbiota de An. atroparvus, entre las cuales Pseudomonas, Asaia y Serratia fueron identificadas como candidatas potenciales para control vectorial local. Para evaluar la influencia de ISFVs en la competencia vectorial frente a la transmisión de RVFV (Capítulo 2), primero se estudió la infección de Culex flavivirus (CxFV) en Cx. pipiens a través de exposición oral e inoculación intratorácica. CxFV infectó a Cx. pipiens después de inoculaciones intratorácicas pero no a través de la exposición oral. Los ensayos de competencia vectorial frente a RVFV se realizaron en co-infección con CxFV y un flavivirus de mosquito de circulación natural, respectivamente, en Cx. pipiens y Ae. vexans. Ambas poblaciones mostraron ser competentes para RVFV después de exposición oral. Por otra parte, CxFV ni RVFV interfirieron con su respectiva infección, mientras que el flavivirus de mosquito moduló la susceptibilidad de infección con RVFV en Ae. vexans, sugiriendo su potencial uso como agente biológico para la prevención de la transmisión de RVFV. Finalmente, para evaluar nuevas alternativas para la detección de virus circulantes y vigilancia de arbovirus (Capítulo 3), tarjetas FTA con cebo de miel fueron expuestas a mosquitos capturados en el campo durante jornadas de vigilancia entomológica para su posterior análisis mediante NGS. Virus asociados a artrópodos y plantas fueron identificados en las FTAs y genomas virales casi completos fueron obtenidos, lo que sugiere una buena preservación de ARN viral. Para confirmar la presencia de virus asociados con mosquitos en los especímenes capturados, los pools de mosquitos fueron analizados usando RT-PCR y primers especie-específicos diseñados a partir de las secuencias obtenidas de las FTAs. Virus relacionados con Alphamesonivirus, Quaranjavirus y Bunyavirales no clasificados fueron detectados en mosquitos de Cataluña constituyendo el primer registro de distribución de estos virus en mosquitos europeos. La detección de ISVs en la saliva de mosquitos de forma silvestre demuestra la viabilidad de este método para monitorear la fracción transmisible del virroma de mosquitos y su utilidad en la vigilancia de arbovitus. El presente trabajo contribuye con información para un mejor entendimiento de los factores detrás de la estructura del microbioma de mosquitos locales y su potencial influencia en la competencia vectorial frente a arbovirus. Adicionalmente, provee un nuevo método para complementar la vigilancia de arbovirus en zonas susceptibles, así como, para la detección de nuevos virus circulantes y potencialmente patogénicos The threat of the resurgence or introduction of mosquito-borne diseases, such as malaria and Rift Valley fever, into the European continent has awakened new interests in studying the microbiome associated to autochthonous mosquitoes for better understanding mosquito-pathogen interaction and developing ecologically adequate vector surveillance and control tools. Consequently, this thesis aimed to i) explore the microbiota of Anopheles atroparvus, a vector involved in malaria transmission in Europe, ii) assess the influence of insect-specific flaviviruses on the vector competence of European Culex pipiens and Aedes vexans for the transmission of RVFV, and iii) apply metagenomics on FTA cards as a new approach for virus detection and arbovirus surveillance. In the first chapter, a laboratory colony of An. atroparvus from the Ebro Delta was established, and its rearing protocol updated. Sequencing of the bacterial 16S rRNA gene showed that the breeding environment, physiology and foraging habits influenced the microbiota of field-caught and laboratory-colonized mosquitoes. Diversity analyses showed inter-sample variation among sylvan developmental stages and a diversity decline in adult females after ten-laboratory generations. Nonetheless, a significant fraction of the microbiota was conserved from wild-caught specimens until the tenth laboratory-generation. Environmentally acquired Gram-negative proteobacteria dominated the microbiota of this anopheles population, among which, Pseudomonas, Asaia and Serratia were identified as potential candidates to be studied for local vector control. To assess the influence of ISFVs on the vector competence for the transmission of RVFV (Chapter 2), the infection of Culex flavivirus (CxFV) was first studied in Cx. pipiens by oral exposure and intrathoracic inoculations. CxFV infected Cx. pipiens after intrathoracic inoculations but not after oral exposure. Then, RVFV vector competence assays in co-infection with CxFV and a mosquito-flavivirus of natural circulation were conducted in Cx. pipiens and Ae. vexans respectively. Both Catalonian species showed to be competent vectors for RVFV after oral exposure. CxFV nor RVFV interfered with each other's infection, while, naturally infecting mosquito-flavivirus modulated RVFV infection susceptibility in Ae. vexans, suggesting its potential use as bio-agent for preventing RVFV transmission. Finally, to assess new alternatives for circulating viruses' detection and arboviral surveillance (Chapter 3), next generation sequencing was applied on honey-baited FTA cards that were exposed to field-captured mosquitoes during entomological surveys. Arthropod- and plant-infecting viruses were identified on FTAs and near-complete viral genomes were obtained suggesting good quality preservation of viral RNAs. To confirm the presence of mosquito-associated viruses in the captured specimens, mosquito pools were screened using reverse-transcription PCRs and species-specific primers designed from the sequences obtained from the FTAs. Viruses related to Alphamesonivirus, Quaranjavirus and unclassified Bunyavirales were detected in Catalonian mosquitoes. These findings constitute the first distribution record of these insect-specific viruses in European mosquitoes. Detecting ISVs in mosquitoes' saliva in field conditions demonstrate the feasibility of this approach to monitor the transmissible fraction of the mosquitoes' virome and its suitability for arbovirus surveillance. Overall, the present work contributes with valuable information for better understanding the factors behind the structure of the microbiome of local vector mosquitoes, its potential influence in vector competence, and provides a new approach to complement arbovirus surveillance in susceptible areas and to detect circulating and new potentially pathogenic viruses.

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 household's overall effort to reduce mosquitoes alongside source reduction, but that source reduction and GATs may not limit mosquito infestation at the yard scale. Households with middle incomes, further from town greenspace were less likely to deploy GATs along with respondents who spent less time outdoors, were less favorable toward University Park's GAT Program, and could not name ATM as University Park's most common human-biting mosquito. Respondent familiarity of ATM was lower in renters than homeowners, and respondent favorability towards University Park's GAT program was lower in households with children, and with respondents that do fewer yard activities and who had resided for less time in the town. The results of this study show that a citizen-led mosquito-control program using a passive lethal oviposition trap is still effective, four years after its inception, and that there were specific social and environmental predictors of household participation. In this thesis, I will discuss these results and their implications for bottom-up, citizen-led, control of ATM and other Aedes in other residential communities and demonstrate a framework for understanding drivers of participation and success in community-led environmental management.

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 heterogeneous canopy cover. Previous work suggested that phenology has a considerable impact on Culex species dynamics; Cx. restuans was thought to be an early season species that cedes to Cx. pipiens over the course of the season. Initially, I did not detect an effect of season on Culex spatiotemporal dynamics when collections were undertaken from June through October, but when I expanded the collection season to include the months of April and May, the influence of season was evident. Therefore, the hallmark “crossing-over” point that is common in the Culex literature happens prior to the local mosquito abatement season in Washington and D.C. and Maryland. During the active surveillance and management period, season has little impact on Culex species abundance as compared to environmental factors measured along our urban to rural gradient. A replicated comparison of the abundance and relative frequency of Cx. pipiens and Cx. restuans along urbanization gradients in Washington D.C., greater Philadelphia, PA and greater Chicago, IL, using gradient forests demonstrated that phenology was consistently the most important predictor of the shift between a Cx. restuans-dominant community and a Cx. pipiens-dominant community. This crossing-over point trended later in the season with increasing latitude. Turnover in species abundance tended to occur at intermediate points along environmental gradients associated with urbanization, like percent impervious surface, percent tree cover, distance to city center, and vegetation index. Results of two analytical approaches (ordination and regression trees) and from three metropolitan areas support Cx. restuans as an early season species that is otherwise associated with sites with cooler temperatures, less impervious surface, more tree cover, a shallower water table, and increased distance from city center. Conversely, Cx. pipiens is more abundant than Cx. restuans in sites that are more characteristic of urbanization. Culex pipiens is globally ubiquitous and was common across site classes in the three localities in this study. This species comprises two bioforms, pipiens and molestus, which are characterized by divergent ecological, physiological, and behavioral traits. These bioforms can interbreed in the field and the lab. However, at all sites analyzed across three northeastern metropolitan areas, analysis of genotypes at a single neutral locus violated assumptions of Hardy Weinberg Equilibrium, suggesting that there is not unrestricted geneflow between bioforms across the landscape. The proportion of molestus alleles increased with increasing percent impervious surface and decreased vegetation, two environmental correlates of urbanization. Molestus alleles may confer an advantage in urban environments because they can leverage human infrastructure to overcome thermal limitations and persist in isolated belowground populations via autogeny and use of mammalian hosts. Overall, Culex WNv vectors are differentially distributed across urban to rural gradients in the northeastern United States. These aspects are influenced by a heterogeneous land use and landscape-level changes associated with urbanization. A clear understanding of vector life history, genetics, interspecies interactions, and distribution across the landscape can improve practitioners’ power and precision in predicting and managing vector borne disease transmission. While some patterns in species distribution and composition were universal across metropolitan areas, there was variation between localities that could significantly contribute to WNv transmission and human disease risk. Therefore, I conclude that modeling, as well as development of surveillance and management strategies for WNv vectors should be implemented locally to have the greatest impact on public health outcomes.

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.

Shuni virus is associated with neurologic and febrile illness in animals and humans. To determine potential vectors, we collected mosquitoes in South Africa and detected the virus in species of the genera Mansonia, Culex, Aedes, and Anopheles. These mosquitoes may be associated with Shuni virus outbreaks in Africa and emergence in other regions.

Background and Objectives: Mosquito-borne viral diseases (MBVDs) create a dramatic health situation worldwide. There is a need to improve the understanding of factors to be addressed in intervention programmes. This study explored community knowledge, attitudes, and practices (KAP) regarding MBVD in Kinshasa. Materials and Methods: A cross-sectional survey was carried out between January and April 2019. The socio-demographic and KAP data collected through a questionnaire were analysed using Epi Info 7. Results: The study included 1464 male and female respondents aged from 18 to 70 years old. Open garbage cans and outdoor water storage units were found in 61.2% and 33.4% of respondent residences, respectively. Polluted water bodies (80.3%) were the most mentioned as mosquito breeding places. Among 86.6% of the respondents that had heard about yellow fever, 12% knew that it is an MBVD. The majority of respondents (72.5%) were perceived to be at risk of contracting MBVD. Environment sanitation (58%) and insecticide use (25%) were among the measures implemented to control mosquitoes. The greater overall knowledge score and attitude were not associated with good practice. Conclusion: The residents of Kinshasa had limited knowledge of MBVD. Raising awareness and educational sessions are essential in empowering the community regarding the correct attitudes and practices to effectively manage the risk posed by MBVD.

With vector-borne diseases rising globally and mosquitoes expanding their habitats due to climate change, mosquito control is undoubtedly one of the main challenges for human health in the years to come. This thesis is devoted to the modeling, analysis and simulation of mosquito and mosquito-borne diseases optimal control strategies using modified vector releases. We first investigate optimal population replacement strategies. These consist in replacing optimally the wild population by a population carrying the endosymbiotic bacterium Wolbachia, since it has been shown that mosquitoes carrying this bacterium are less likely to transmit some arboviruses. By considering a high fecundity limit we reduce the study of the mosquito population to a single equation on the proportion of Wolbachia-infected mosquitoes. First, we study strategies optimizing a convex combination of both the cost of the releases and the performance of the technique. We fully analyse this problem, proving a time monotonicity property on the proportion of Wolbachia-infected mosquitoes and using a reformulation of the problem based on a suitable change of variable. Next, we consider the spatial optimization of the releases, optimizing a single instantaneous release at the initial time maximising the final proportion of Wolbachia-infected mosquitoes throughout the domain at a given time horizon. We fully characterize the solutions under some hypothesis in the non-diffusive case. Moreover, simulations are carried for the case with diffusion. Finally, we extend the focus of the study to humans. We consider an epidemiological model in which both populations are taken into account as well as the dynamics of a vector-borne disease with exclusively human-mosquito and mosquito-human transmission like dengue. In this setting, we minimise the amount of human infections during an outbreak using instantaneous releases of modified vectors, represented by linear combinations of Dirac measures with positive coefficients determining their intensity. Optimal strategies for both population replacement and the sterile insect technique are studied numerically using ad hoc algorithms, based on writing first-order optimality conditions characterizing the best combination of Dirac measures.; Avec la hausse globale des maladies à vecteurs et l’expansion des habitats des moustiques dues au changement climatique, le contrôle des populations de moustiques est sans doute un des principaux défis pour la santé humaine dans les années à venir. Cette thèse est consacrée à la modélisation, l’analyse et la simulation de stratégies optimales de contrôle des moustiques et des maladies qu’ils transmettent en utilisant des lâchers de spécimens modifiés. Nous étudions d’abord les stratégies optimales de remplacement de population. Celles-ci consistent à remplacer de manière optimale la population sauvage par une population porteuse de la bactérie endosymbiotique Wolbachia, car il a été démontré que les moustiques porteurs de cette bactérie sont moins susceptibles de transmettre certains arbovirus. En considérant une limite de fécondité élevée, nous réduisons l’étude de la population de moustiques à une seule équation sur la proportion de moustiques infectés par Wolbachia. Nous étudions d’abord des stratégies optimisant une combinaison convexe du coût des lâchers et de la performance de la technique. Nous effectuons une analyse complète de ce problème, en prouvant une propriété de monotonie temporelle sur la proportion de moustiques infectés par Wolbachia et en utilisant une reformulation du problème basée sur un changement de variable approprié. Dans un deuxième temps, nous considérons l’optimisation spatiale des lâchers, en optimisant un seul lâcher instantané à l’instant initial maximisant la proportion finale de moustiques infectés par Wolbachia dans le domaine à un horizon temporel donné. Nous caractérisons complètement les solutions sous certaines hypothèses dans le cas non-diffusif. De plus, des simulations sont effectuées pour le cas avec diffusion. Enfin, nous étendons l’objet de l’étude aux humains. Nous considérons un modèle épidémiologique dans lequel les deux populations sont prises en compte ainsi que la dynamique d’une maladie vectorielle avec une transmission exclusivement homme-moustique et moustique-homme comme la dengue. Dans ce cadre, nous minimisons la quantité d’infections humaines pendant une épidémie en utilisant des lâchers instantanés de spécimens modifiés, représentés par des combinaisons linéaires de mesures de Dirac avec des coefficients positifs déterminant leurs intensités. Les stratégies optimales pour le remplacement de population et la technique de l’insecte stérile sont étudiées numériquement à l’aide d’algorithmes ad hoc, basés sur l’écriture de conditions d’optimalité au premier ordre caractérisant la meilleure combinaison de mesures de Dirac.

Background Mosquitoes are important vectors of disease-causing organisms such as filarial worms, malaria parasites, and arboviruses endemic to sub-Saharan Africa including Nigeria. Malaria is a disease caused by a plasmodium parasite, transmitted by the bite of infected mosquitoes and is no doubt a public health concern. There is limited information on the genetic diversity of mosquitoes in Nigeria. This is necessary because information about the genetic diversity of mosquitoes is a very important step towards vector control and management with the aim to mitigate or eliminate burden resulting from malaria and other diseases caused by mosquitoes. In the present study, we investigated the genetic variability and relatedness of mosquitoes based on the DNA sequences of the mitochondrial cytochrome oxidase subunit I (COI) and ribosomal intergenic non-coding spacer gene regions (IGS). Mosquitoes were collected from five different states in Northcentral Nigeria, they were morphologically identified using standard keys and genomic DNA was extracted. The specific regions of interests were amplified, and the PCR products were then sequenced. Results PCR was able to successfully amplify the expected amplicon sizes of COI and IGS sequences (710 and 169) base pairs, respectively. For COI sequence, pairwise genetic distance between mosquito species ranged from 0.00 to 0.17 in the COI sequences. The pairwise genetic distance among Culex, Aedes and Anopheles species in the IGS sequences ranged from 0.000 to 0.118. Phylogenetic analysis of the sequences of the mitochondrial cytochrome oxidase subunit showed that there was genetic diversity amongst the different mosquito species sampled. It effectively showed marked differences between Culicine and Anopheline mosquitoes. Conclusions The ribosomal IGS primers used for this study only amplified Anopheles spp. However, it revealed that there is diversity among the Anopheles gambiae and Anopheles arabiensis samples collected. This study concludes that the mitochondrial COI and ribosomal IGS gene regions are reliable markers for mosquito genetic diversity study and will surely yield a reliable result for molecular diversity assessment of mosquito species.

Background Arbovirus surveillance and recurrence of outbreaks in Kenya continues to reveal the re-emergence of viruses of public health importance. This calls for sustained efforts in early detection and characterization of these agents to avert future potential outbreaks. Methods A larval survey was carried out in three different sites in Kwale County, Vanga, Jego and Lunga Lunga. All containers in every accessible household and compound were sampled for immature mosquitoes. In addition, adult mosquitoes were also sampled using CO2-baited CDC light traps and BG-Sentinel traps in the three sites and also in Tsuini. The mosquitoes were knocked down using trimethylamine and stored in a liquid nitrogen shipper for transportation to the laboratory where they were identified to species, pooled and homogenized ready for testing. Results A total of 366 houses and 1730 containers were inspected. The House Index (HI), Container Index (CI) and Breateau Index (BI) for Vanga Island were (3%: 0.66: 3.66) respectively. In Jego, a rural site, the HI, CI and BI were (2.4%: 0.48: 2.4) respectively. In Lunga Lunga, a site in an urban area, the HI, CI and BI were (22.03%: 3.97: 29.7) respectively. The indices suggest that this region is at risk of arbovirus transmission given they were above the WHO threshold (CI > 1, HI > 1% and BI > 5). The most productive containers were the concrete tanks (44.4%), plastic tank (22.2%), claypot (13.3%), plastic drums (8.9%), plastic basins (4%), jerricans (1.2%) and buckets (0.3%). Over 20,200 adult mosquitoes were collected using CDC light traps, and over 9,200 using BG- sentinel traps. These mosquitoes were screened for viruses by inoculating in Vero cells. Eleven Orthobunyavirus isolates were obtained from pools of Ae. pembaensis (4), Ae. tricholabis (1), Cx. quinquefasciatus (3), Culex spp. (1) and Cx. zombaensis (2). Five of the Orthobunyaviruses were sequenced and four of these were determined to be Bunyamwera viruses while one isolate was found to be Nyando virus. One isolate remained unidentified. Conclusions These results indicate circulation of Orthobunyaviruses known to cause diverse grades of febrile illness with rash in humans in this region and highlights the need for continued monitoring and surveillance to avert outbreaks.

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.

Background and aimDespite the fact that the chikungunya viral infection is a neglected disease, complications such as hemorrhagic fever, arthritis, and lymphopenia remain a health concern. The aim of this study was to determine the prevalence of the chikungunya virus in the Southern Region, Saudi Arabia. Enzyme immunoassay and polymerase chain reaction have been compared between samples.Materials and methodsForty samples from two southern hospitals in Saudi Arabia were collected between December 2019 and February 2020 and screened for chikungunya virus IgG antibodies and for viral RNA. Selection criteria were based on hematological parameters and rheumatological profiles such as rheumatoid factor, c-reactive protein, anti-nuclear antibody, and anti-cyclic citrullinated peptide (anti-CCP) of out-patients.ResultsOne confirmed case of chikungunya virus was detected using the ELISA test. However, no viral RNA was detected in any of the samples. This suggests that the virus is cleared rapidly in patients.ConclusionChikungunya is a neglected viral disease in Saudi Arabia. Future work should focus on detailed investigation of this viral infection and its vectors.

Effective capture and elimination of indoor resting mosquito population is important in the fight against mosquito borne diseases. This study aimed at evaluating the efficacy of a simply resting box baited with crude fruit and leaf ethanol extracts of Phytolacca dodecandra in attracting and killing indoor mosquitoes at Korando, Western Kenya. The study was conducted in three phases: pre-intervention, intervention and post intervention. Simple resting boxes made from galvanized wire frame measuring 30 cm × 30 cm × 30 cm, covered in blue and black tunic in and out and lined with carton boards were used. The boxes were baited with socks with strong human odour and 80ml/100mls (e/w) solution of either crude ethanol fruit or leaf extracts of P. dodecandra, ethanol leaf extracts of Azadiracta indica or Deltamethrin. Deltamethrin and Azadiracta indica were used as positive and water as negative control. The treatments were applied at the intervention phase only. The boxes were left overnight in the houses and mosquitoes collected by 6.30 hours. It was observed that more Culicines than Anopheline were captured irrespective of phase or treatment used. Mosquito densities reduced with phase of activity. P. dodecandra leaf extracts killed more mosquitoes than fruit or A. indica leaf extracts though the number were less than that of Deltamethrin or WHO threshold of > 80% mortality. In conclusion, the simple resting boxes were effective in collecting and killing indoor mosquitoes though lethality did not matched the WHO threshold. With improved structural set up and use of pure extracts of P. dodecandra, the resting boxes can serve as effective tools for capture, elimination and management of mosquito borne diseases.

Insecticide resistance is a major threat challenging the control of harmful insect species. The study of resistant phenotypes is, therefore, pivotal to understand molecular mechanisms underpinning insecticide resistance and plan effective control and resistance management strategies. Here, we further analysed the diflubenzuron (DFB)-resistant phenotype due to the point-mutation I1043M in the chitin-synthase 1 gene (chs1) in the mosquito Culex pipiens. By comparing susceptible and resistant strains of Cx. pipiens through DFB bioassays, molecular analyses and scanning electron microscopy, we showed that the I1043M-resistant mosquitoes have: (i) a striking level of DFB resistance (i.e., resistance ratio: 9006); (ii) a constitutive 11-fold over-expression of the chs1 gene; (iii) enhanced cuticle thickness and cuticular chitin content. Culex pipiens is one of the most important vector species in Europe and the rapid spread of DFB resistance can threaten its control. Our results, by adding new data about the DFB-resistant phenotype, provide important information for the control and management of insecticide resistance.

Funding Information: Eddyson Montalvo-Sabino was recipient of a grant from “Programa Nacional de Becas y Crédito Educativo” (PRONABEC), 2019—Beca Generacion del Bicentenario, from the “Ministerio de Educación” of Peru. A.P. Abilio was a recipient of a grant from Wellcome Trust (Grant WT087546MA) through SACIDS RVF and NPHI-Phase-II from the National Institute for Health of Mozambique through a cooperative agreement number [5NU14GH001237-03-00]. Marietjie Venter was a recipient of a sub-award from the Global Disease Detection Program, US-CDC award 5U19GH000571-02 with the NICD and University of Pretoria that funded vector surveillance in South Africa (2012–2015) and by the Cooperative Agreement Number (5 NU2GGH001874-02-00) with the University of Pretoria (2014–2017). Milehna M. Guarido received a studentship through this grant. A.P.G. Almeida has been a recipient of the Visiting Professor Programme by the University of Pretoria for the work in South Africa. This work received financial support from the Global Health and Tropical Medicine Center (GHTM|IHMT|NOVA), which is funded through FCT contract UID/Multi/04413/2013, Portugal. The findings and conclusions expressed in this manuscript are those of the author(s) and do not necessarily represent the official position of the funding agencies. Publisher Copyright: © 2022 by the authors. Potential arboviral Afrotropical mosquito vectors are underrepresented in public databases of CoxI barcode sequences. Furthermore, available CoxI sequences for many species are often not associated with voucher specimens to match the corresponding fine morphological characterization of specimens. Hence, this study focused on the characterization of Culicine mosquitoes from South Africa, Mozambique, and Angola and their classification using a complementary approach including a morphological analysis of specimens’ genitalia and phylogenetic study based on the analysis of CoxI barcode sequences using maximum likelihood and Bayesian phylogenetic inference methods, alongside Median-Joining Network and PCOORD analyses. Overall, 800 mosquitoes (652 males and 148 females) from 67 species, were analyzed. Genitalia from 663 specimens allowed the identification of 55 species of 10 genera. A total of 247 CoxI partial gene sequences corresponding to 65 species were obtained, 11 of which (Aedes capensis, Ae. mucidus, Culex andersoni, Cx. telesilla, Cx. inconspicuosus, Eretmapodites subsimplicipes, Er. quinquevittatus, Ficalbia uniformis, Mimomyia hispida, Uranotaenia alboabdominalis, and Ur. mashonaensis) are, to the best of our knowledge, provided here for the first time. The presence of Cx. pipiens ecotypes molestus and pipiens and their hybrids, as well as Cx. infula, is newly reported in the Afrotropical region. The rates of correct sequence identification using BOLD and BLASTn (≥95% identity) were 64% and 53%, respectively. Phylogenetic analysis revealed that, except for subgenus Eumelanomyia of Culex, there was support for tribes Aedini, Culicini, Ficalbiini, and Mansoniini. A divergence >2% was observed in conspecific sequences, e.g., Aedeomyia africana, Ae. cumminsii, Ae. unilineatus, Ae. metallicus, Ae. furcifer, Ae. caballus, and Mansonia uniformis. Conversely, sequences from groups and species complexes, namely, Ae. simpsoni, Ae. mcintoshi, Cx. bitaeniorhynchus, Cx. simpsoni, and Cx. pipiens were insufficiently separated. A contribution has been made to the barcode library of Afrotropical mosquitoes with associated genitalia morphological identifications. publishersversion published

Background: Tahyna orthobunyavirus (TAHV) is a neglected mosquito-borne bunyavirus. Although the virus is widespread in continental Europe, TAHV infections are rarely reported. We analyzed the prevalence of TAHV in humans and different animal species as well as mosquitoes collected in urban areas of Zagreb and its surroundings in the period from 2020 to 2022. Methods: The study included 32 patients with neuroinvasive disease (NID), 218 asymptomatic individuals, 98 horses, 94 pet animals (dogs and cats), and 4456 Aedes vexans mosquitoes. Cerebrospinal fluid (CSF) and urine samples of patients with NID were tested for the TAHV RNA using a real-time reverse transcription-polymerase chain reaction (RT-qPCR). Human and animal serum samples were tested for TAHV-neutralizing (NT) antibodies using a virus-neutralization test (VNT). Mosquito pools were tested for TAHV RNA using an RT-qPCR. Results: TAHV NT antibodies were detected in 3/9.4% of patients with NID, 8/3.7% of asymptomatic individuals, 29/29.6% of horses, and 11/11.7% of pet animals. There was no difference in the seroprevalence according to age, sex, and area of residence in asymptomatic individuals. In addition, TAHV seropositivity did not differ according to age and sex in pet animals. None of the tested mosquito pools was TAHV RNA-positive. Conclusions: The presented results highlight the importance of interdisciplinary surveillance (“One Health”) of this neglected viral zoonosis.

In our natural product screening program, we screened natural products for their repellency and toxicity against insect vectors. Methanolic extract of aerial parts of Stenaria nigricans (Lam.), with no published chemistry, was tested for repellency against mosquitoes and imported hybrid fire ants. Methanolic extracts showed biting deterrence similar to DEET (N,N-diethyl-3-methylbenzamide) against Aedes aegypti L. Based on this activity, the crude extract was fractionated into chloroform, ethyl acetate, and methanol subfractions. The active methanolic subfraction was further fractionated into 13 subfractions. These fractions were tested for their biting deterrence against Ae. Aegypti. Active subfractions were further characterized to identify the compounds responsible for this activity. Four undescribed iridoid glucosides (1–4) and three previously reported compounds (5–7) were isolated from active subfractions and tested for their biting deterrent activity. Based on BDI values, compounds 2, 3, 6, and 7, with biting deterrence similar to DEET, showed the potential to be used as repellents against mosquitoes. In an in vitro digging bioassay, none of these compounds showed any repellency against hybrid imported fire ants at a dose of 125 µg/g. This is the first report of biting deterrence and repellency of S. nigricans extract and its pure compounds, iridoid glucosides against mosquitoes and imported fire ants. Further studies will be conducted to explore the repellent potential of these compounds in different formulations under field conditions.

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”

International audience; Mosquitoes (Diptera: Culicidae) are of significant public health importance because of their ability to transmit major diseases to humans and animals, and are considered as the world’s most deadly arthropods. In recent decades, climate change and globalization have promoted mosquito-borne diseases’ (MBDs) geographic expansion to new areas, such as North African countries, where some of these MBDs were unusual or even unknown. In this review, we summarize the latest data on mosquito vector species distribution and MBDs affecting both human and animals in North Africa, in order to better understand the risks associated with the introduction of new invasive mosquito species such as Aedes albopictus. Currently, 26 mosquito species confirmed as pathogen vectors occur in North Africa, including Aedes (five species), Culex (eight species), Culiseta (one species) and Anopheles (12 species). These 26 species are involved in the circulation of seven MBDs in North Africa, including two parasitic infections (malaria and filariasis) and five viral infections (WNV, RVF, DENV, SINV and USUV). No bacterial diseases have been reported so far in this area. This review may guide research studies to fill the data gaps, as well as helping with developing effective vector surveillance and controlling strategies by concerned institutions in different involved countries, leading to cooperative and coordinate vector control measures.

Raw data for project examining Culex mosquito oviposition preferences

V zadnjih letih postajajo botanični repelenti za žuželke vse bolj priljubljeni kot alternativa sintetičnim kemičnim repelentom proti škodljivcem, saj naj bi predstavljali zmanjšano tveganje za okolje in zdravje ljudi. N,N-dietil-3-metilbenzamid (DEET) je trenutno najboljši razpoložljivi repelent predvsem za komarje in klope, vendar strokovnjaki poročajo o primerih iritacije kože, izpuščajih in nekaterih primerih nevroloških težav pri otrocih po uporabi DEET, zato se je zanimanje potrošnikov za naravne alternativne repelente hitro povečalo. Zaradi povzročene škode in prizadevanj za njihovo obvladovanje invazivne vrste komarjev svetovno gospodarstvo letno stanejo več milijonov dolarjev. Prav tako se povečujejo stroški invazivnih tujerodnih rastlin, zato se zaradi globalnih in lokalnih vplivov pojavlja vse večja potreba po ukrepanju, zgodnjem odkrivanju, ozaveščanju in hitrem odzivanju. To je ključnega pomena za preprečevanje nadaljnjega širjenja teh vrst. Namen magistrskega dela je bil načrtovati, razviti, izdelati in testirati prototipe etiketnih nalepk iz invazivnih tujerodnih rastlin s premazom, ki vsebuje eterična olja na poroznih nosilcih, ki služijo kot zaščita pred piki komarjev in podobnimi krvosesnimi žuželkami. Raziskava repelentnih etiketnih nalepk je bila izdelana v sodelovanju s Fakulteto za farmacijo in je obravnavala sproščanje in repelentnost posameznih mešanic v kombinaciji s premazom na različnih papirnih podlagah iz invazivnih tujerodnih rastlin.Testiranih je bilo 6 različnih vzorcev, kjer smo za osnovo papirne podlage uporabili japonski dresnik (Fallopia japonica), rozgo (Solidago gigantea) in akacijo (Robinia pseudoacacia), premazali pa smo jih z dvema različnim mešanicama eteričnih olj, katere smo vezali na porozne nosilce SYLOID® XDP (W. R. Grace & Co.-Conn., ZDA) za daljše izhlapevanje in delovanje. Ugotovljeno je bilo, da naše repelentne etiketne nalepke uspešno delujejo v boju proti komarjem. Največjo uspešnost je dosegel vzorec iz osnove japonskega dresnika s premazno mešanico, ki je vsebovala mešanico eteričnih olj geranije, sivke in evkaliptusa. Poleg repelentne učinkovitosti nudijo nalepke učinkovito možnost uporabe invazivnih tujerodnih rastlin v obliki repelentnih etiketnih nalepk proti komarjem. In recent years, botanical insect repellents have become increasingly popular as an alternative to synthetic chemical pesticides as they are thought to pose a risk to the environment and human health. N,N-diethyl-3-methylbenzamide (DEET) currently remains the best available repellent against mosquitoes and ticks, but there were some cases of skin irritation, rashes and neurological problems in children that have been reported after DEET use, so interest in natural alternatives has increased. Invasive mosquito species cost the global economy millions of dollars annually in the damage caused and efforts to control them. The costs of invasive alien plants are also on the rise, with global and local influences increasing the need for action, early detection, awareness and rapid response, which has proved crucial to prevent further spread of these species. The purpose of the master's thesis was to design, develop, manufacture and test prototypes of stickers from invasive alien plants with a coating containing repellent encapsulation of essential oils to protect against mosquito bites and similar blood-sucking insects. The research of repellent label labels was made in collaboration with the Faculty of Pharmacy and addressed the release and repellency of individual mixtures in combination with coating on different paper substrates from invasive alien plants. Six different samples of Japanese knotweed (Fallopia japonica), Goldenrod (Solidago gigantea) and Robinia (Robinia pseudoacacia), were coated with two different mixtures of essential oils and tested. They were encapsulated on solid SYLOID® XDP (W. R. Grace & Co.-Conn., ZDA) carriers, for longer evaporation. Our repellent label labels have been found to work successfully in the fight against mosquitoes. The greatest success was achieved by the sample of Japanese knotweed with a coating mixture containing a mixture of essential oils of geranium, lavender and eucalyptus. In addition to repellent efficacy, labels are an effective option for the use of invasive alien plants in the form of mosquito repellent labels.

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.

Introduction. Global climate changes affect the habitats of insects, including mosquitoes, which are carriers of dangerous natural focal infections. When mosquitos develop new territories, they create a potential threat to people who find themselves in these areas. In the Krasnodar Region, a stable population of Ae. albopictus mosquitoes was formed in the 21st century. These mosquitoes are carriers of many viral pyrrhoid-focal infections, such as Dengue, Chikungunya, Zika fever and Yellow fever. Estimations of biological, epidemiological and cultural data can help to answer the question of the probability of occurrence of autochthonous cases of infection.Aim. To estimate the probability of occurrence of autochthonous cases of viral infections carried by Ae. albopictus mosquitoes on the territory of the Black Sea coast of the Krasnodar territory. For the review, we used scientific publications describing the occurrence of autochthonous diseases in similar climate zones inhabited by Ae. albopictus mosquitoes, the biology of these mosquitoes, as well as official reports of the sanitary services of Europe and the Russian Federation. A stable population of Ae. albopictus mosquitoes has formed on the Black Sea coast of the Krasnodar Territory. The local climate, including the temperature range is favourable for active reproduction of vectors and autochthonous transmission of viral infection.Conclusion. Despite the favourable conditions for the release of mosquitoes and the formation of a stable population, autochthonous transmission requires the introduction of the source of infection during the viremia period to infect the mosquito population. In recent years, isolated cases of such drifts have been reported in the Krasnodar Territory, which indicates a low probability of local cases of transmission. However, with the development of the tourism sector, the flow of tourists from endemic areas will inevitably increase. In addition, the increase in the well-being of the population, trips to these countries will become more frequent this may well increase the risk of transmission of viral infections by local mosquitoes. In any case, the weakening of epidemic control of mosquitoes and medical surveillance of imported cases of tropical fevers will have serious consequences.

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).

Aedes aegypti transmits viruses that cause diseases such as dengue, yellow fever, Zika and chikungunya. Chemical pesticides have been used to control this vector, but mosquitoes have developed resistance to insecticides. Biological control with microorganisms and plant extracts are effective alternatives for the management of insect vector populations and introduce less pollutants into the environment. The objective of this research was to evaluate the larvicidal activity of Bacillus thuringiensis subsp. israelensis (Bti) and extracts of Annona muricata, Ricinus communis and Sapindus saponaria for the biological control of A. aegypti larvae. For this, ethanolic extracts of seeds or fruits of the three plant species were obtained and lethal concentrations for 50% mortality of the extracts and bacteria were determined. Subsequently, combinations of the extracts with Bti were made and the interactions were evaluated. Both bacteria and plant extracts showed larvicidal activity. Mixtures of Bti with the ethanolic extracts of R. communis and S. saponaria generated an antagonistic effect, while in combination with ethanolic extracts of A. muricata presented an independent action effect. Therefore, the addition of the ethanolic extract of A. muricata seeds to sporulated cultures of Bti could be considered more effective for the biological control of A. aegypti than with each compound separately. Resumen El díptero Aedes aegypti es trasmisor de virus causantes de enfermedades como dengue, fiebre amarilla, Zika y chikunguña; para el control de este vector se utilizan pesticidas químicos frente a los cuales los mosquitos han generado resistencia. El control biológico con microorganismos y extractos vegetales es una alternativa de manejo de las poblaciones de insectos vectores efectiva y menos contaminante para el ambiente. El objetivo de esta investigación fue evaluar la actividad larvicida de mezclas de Bacillus thuringiensis subsp. israelensis (Bti) y extractos de Annona muricata, Ricinus communis y Sapindus saponaria para el control biológico de larvas de A. aegypti. Para ello se obtuvieron extractos etanólicos de semillas o frutos de las tres especies vegetales y se determinaron las concentraciones letales 50 de los extractos y la bacteria. Posteriormente se realizaron combinaciones de los extractos con Bti y se evaluó el efecto de dichas interacciones. Tanto la bacteria como los extractos vegetales presentaron actividad larvicida. Se encontró que las mezclas de Bti con el extracto etanólico de R. communis y S. saponaria generaron un efecto antagónico, mientras que la combinación con A. muricata presentó una acción independiente. La adición del extracto etanólico de semillas de A. muricata a cultivos esporulados de Bti se podría considerar una alternativa más efectiva para el control biológico de A. aegypti que con cada uno de estos compuestos por separado.

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.