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1.
Indian J Public Health ; 68(1): 3-8, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38847625

RESUMO

BACKGROUND: To control mosquito vectors causing human diseases, bacterial biopesticides are currently in use. Indeed, the recent development of resistance to these bacterial agents has impeded its applications. Under these circumstances, the search for novel bacterial agents with mosquitocidal activity is unavoidable. In this study, a novel mosquitocidal bacterium was isolated from red soils of agricultural field. OBJECTIVES: The objective of this study was to isolate and identify new mosquitocidal bacteria from the natural environment. MATERIALS AND METHODS: Soil samples were collected during 2021-2022 from Tirupathur district of Tamil Nadu, South India. The samples were bioprocessed for culturing the bacterial colony in a suitable culture medium (Nutrient Yeast Salt Medium), and after 72 h, the bacterial cell mass was removed and lyophilized. Bioassays (mosquito toxicity assays) were carried out to screen the bacterial colonies for mosquitocidal effect. The potential colony was further analyzed, and identified for its application in mosquito control. RESULTS: The new isolate screened from red soil was identified as Bacillus thuringiensis subspecies israelensis (VCRC B647) as per the ilvD gene sequence analysis. The strain was found to be potentially effective in controlling mosquito larvae, and further biochemical analyses, bacterial growth, biomass, and protein content were investigated. The new isolate did not show any toxic effect on nontarget aquatic organisms. CONCLUSION: It is significant to depict that the mosquitocidal action of this new isolate (Bti) is highly significant than the reference strain of Bti-H14. It is concluded that this is the first report that an indigenous strain of Bti VCRC B647 is very effective in mosquito control.


Assuntos
Bacillus thuringiensis , Microbiologia do Solo , Índia , Animais , Controle de Mosquitos/métodos , Mosquitos Vetores/microbiologia , Mosquitos Vetores/efeitos dos fármacos , Controle Biológico de Vetores/métodos , Culicidae/efeitos dos fármacos
2.
Math Biosci Eng ; 21(4): 5227-5249, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38872534

RESUMO

Mosquito-borne diseases are threatening half of the world's population. To prevent the spread of malaria, dengue fever, or other mosquito-borne diseases, a new disease control strategy is to reduce or eradicate the wild mosquito population by releasing sterile mosquitoes. To study the effects of sterile insect technique on mosquito populations, we developed a mathematical model of constant release of sterile Aedes aegypti mosquitoes with strong and weak Allee effect and considered interspecific competition with Anopheles mosquitoes. We calculated multiple release thresholds and investigated the dynamical behavior of this model. In order to get closer to reality, an impulsive differential equation model was also introduced to study mosquito suppression dynamics under the strategy of releasing $ c $ sterile male mosquitoes at each interval time $ T $. Finally, the relationship between the releasing amount or the waiting period and the number of days required to suppress mosquitoes was illustrated by numerical simulations.


Assuntos
Aedes , Anopheles , Simulação por Computador , Controle de Mosquitos , Mosquitos Vetores , Dinâmica Populacional , Animais , Controle de Mosquitos/métodos , Masculino , Anopheles/fisiologia , Feminino , Modelos Biológicos , Dengue/prevenção & controle , Dengue/transmissão , Dengue/epidemiologia , Malária/prevenção & controle , Malária/transmissão , Humanos , Culicidae , Comportamento Competitivo
3.
PLoS One ; 19(6): e0303352, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38870118

RESUMO

Mosquito-borne diseases pose a global health threat, with pathogens like Malaria, Dengue fever, and others transmitted by mosquitoes. Our study focuses on evaluating the toxicity of genetically engineered mosquito larvicidal algae (Chlamydomonas reinhardtii) to non-target organisms, specifically Zebrafish. We conducted a 90-day experiment, feeding Zebrafish different combinations of larvicidal algae and commercial fish feed. Statistical analysis revealed no significant differences in mortality, allergenicity, or moribundity among groups. Hematology, molecular analysis, and necropsy showed no physiological differences. Our findings indicate that the transgenic algae (TN72.cry11Ba) had no adverse effects on adult Zebrafish or their larvae. This study confirmed the safety of algae on non-target organisms, such as zebrafish.


Assuntos
Chlamydomonas reinhardtii , Larva , Peixe-Zebra , Animais , Chlamydomonas reinhardtii/genética , Embrião não Mamífero/efeitos dos fármacos , Culicidae , Administração Oral , Inseticidas/toxicidade
4.
Med Trop Sante Int ; 4(1)2024 03 31.
Artigo em Francês | MEDLINE | ID: mdl-38846112

RESUMO

Background and justification: The Republic of Djibouti is located in the Horn of Africa, on the Gulf of Aden and the Bab-el-Mandeb detroit, at the southern entrance to the Red Sea. Prior to its independence in 1977, the Republic of Djibouti was known by two names: "Côte française des Somalis" until 1967, then "Territoire Français de Afars et Issas". As part of our doctoral research on the ecology of mosquitoes in Djibouti, we noted a lack of information on the species encountered, and felt it essential to draw up a list of species before embarking on ecological monitoring. The aim of this work is to survey publications on mosquitoes in Djibouti and to synthesize data from this scientific literature in order to update the national inventory of Culicidae. Materials and methods: An exhaustive search of electronic bibliographic databases (PubMed, Scopus, HAL Open Archive, Science Direct and Google Scholar) was carried out. Reference lists were filtered to access additional articles in order to obtain more data. Two keywords were used: "Djibouti" and "French Territory of Afars and Issas". A selection of scientific publications on Djibouti mosquitoes and/or diseases transmitted by mosquito vectors was made. Researches were conducted in articles selected. The names of the species listed were checked and validated by referring to the site Mosquito Taxonomic Inventory. Results: A total of 13 studies, published between 1970 and 2023, were found. Over the years, the composition of the Culicidae fauna has become well known. In part, the movement of people traveling to and from neighboring countries has been linked to the detection of new species and the reappearance of mosquito species in Djibouti. Numerous studies have been carried out over the years, including purely taxonomic studies and others focusing on the incrimination of mosquito vectors and the characterization of the pathogens they transmit. A total of 37 species, belonging to two subfamilies (Anophelinae and Culicinae), of mosquitoes divided between 7 genera (Aedes, Anopheles, Culex, Culiseta, Lutzia, Mimomyia and Uranotaenia) have been mentioned across the country. The number of species per genus is distributed as follows: 5 species of Aedes including 1 subspecies, 14 species of Anopheles including two subspecies, 12 species of Culex including 1 subspecies, 1 species for each of the genera Culiseta and Lutzia and finally 2 species respectively for the genera Mimomiya and Uranotaenia. Five species have been incriminated as vectors of diseases such as malaria, dengue fever, yellow fever, West Nile virus and chikungunya. Others are known for their potential role in pathogen transmission, including Zika and Rift Valley virus. Discussion - Conclusion: The bibliographical research enabled us to summarize the research carried out over more than half a century in the history of Djibouti, and to update the inventory of the country's mosquitoes, which now includes 37 species. Species names were reviewed and updated, and the case of Anopheles gambiae was also addressed. Two species mentioned as part of the Culicidae fauna of Djibouti appeared to be doubtful and are up for discussion. These results provide a useful information base for defining vector control priorities in Djibouti. They will also inform, guide and facilitate future consultations of our database. In addition, this study will help to identify research ways on mosquitoes in Djibouti.


Assuntos
Culicidae , Animais , Culicidae/classificação , Culicidae/fisiologia , Djibuti , Mosquitos Vetores/classificação
5.
Microb Ecol ; 87(1): 64, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691215

RESUMO

Mosquitoes are a complex nuisance around the world and tropical countries bear the brunt of the burden of mosquito-borne diseases. Rwanda has had success in reducing malaria and some arboviral diseases over the last few years, but still faces challenges to elimination. By building our understanding of in situ mosquito communities in Rwanda at a disturbed, human-occupied site and at a natural, preserved site, we can build our understanding of natural mosquito microbiomes toward the goal of implementing novel microbial control methods. Here, we examined the composition of collected mosquitoes and their microbiomes at two diverse sites using Cytochrome c Oxidase I sequencing and 16S V4 high-throughput sequencing. The majority (36 of 40 species) of mosquitoes captured and characterized in this study are the first-known record of their species for Rwanda but have been characterized in other nations in East Africa. We found significant differences among mosquito genera and among species, but not between mosquito sexes or catch method. Bacteria of interest for arbovirus control, Asaia, Serratia, and Wolbachia, were found in abundance at both sites and varied greatly by species.


Assuntos
Bactérias , Culicidae , Microbiota , Wolbachia , Ruanda , Animais , Culicidae/microbiologia , Wolbachia/genética , Wolbachia/isolamento & purificação , Wolbachia/classificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Mosquitos Vetores/microbiologia , Feminino , Masculino , RNA Ribossômico 16S/genética , Serratia/genética , Serratia/isolamento & purificação , Serratia/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Sequenciamento de Nucleotídeos em Larga Escala
6.
PLoS One ; 19(5): e0303405, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38718006

RESUMO

Entomological research is vital for shaping strategies to control mosquito vectors. Its significance also reaches into environmental management, aiming to prevent inconveniences caused by non-vector mosquitoes like the Mansonia Blanchard, 1901 mosquito. In this study, we carried out a five-year (2019-2023) monitoring of these mosquitoes at ten sites in Porto Velho, Rondônia, using SkeeterVac SV3100 automatic traps positioned between the two hydroelectric complexes on the Madeira River. Throughout this period, we sampled 153,125 mosquitoes, of which the Mansonia genus accounted for 54% of the total, indicating its prevalence in the region. ARIMA analysis revealed seasonal patterns of Mansonia spp., highlighting periods of peak density. Notably, a significant decreasing trend in local abundance was observed from July 2021 (25th epidemiological week) until the end of the study. Wind speed was observed to be the most relevant meteorological factor influencing the abundance of Mansonia spp. especially in the Joana D'Arc settlement, although additional investigation is needed to comprehensively analyze other local events and gain a deeper understanding of the ecological patterns of this genus in the Amazon region.


Assuntos
Culicidae , Estações do Ano , Animais , Culicidae/fisiologia , Mosquitos Vetores/fisiologia , Brasil , Conceitos Meteorológicos
7.
PLoS One ; 19(5): e0303330, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38718075

RESUMO

INTRODUCTION: Workers in the construction industry frequently work in construction sites with numerous areas that can potentially accumulate water, such as tanks, wet cement surfaces, or water puddles. These water collection sites become ideal breeding grounds for mosquito infestation, which leads to a higher prevalence of mosquito-borne diseases, especially malaria and dengue among construction workers. Despite that numerous factors have been identified in controlling vector-borne diseases, the specific factors that influence mosquito control at construction sites have yet to be explored. AIMS: This systematic review aims to determine the factors associated with mosquito control among construction workers. METHODS: Primarily, articles related to factors associated with mosquito control among construction workers were collected from two different online databases (ScienceDirect and EBSCOhost). Two independent reviewers were assigned to screen the titles and abstracts of the collected data, stored in Microsoft Excel, against the inclusion and exclusion criteria. Afterwards, the quality of the included articles was critically assessed using the Mixed Method Appraisal Tool (MMAT). Of the 171 articles identified, 4 were included in the final review. RESULTS: Based on the thorough evaluation, mosquito-related knowledge, practical mosquito prevention measures, and Larval Source Management (LSM) were identified as vital factors associated with mosquito control among construction workers. The significant association between mosquito-related knowledge and control practices indicates higher knowledge linked to effective practices, particularly among female workers and those who were recently infected with malaria. Concurrently, there were notable challenges regarding sustainable preventive measures and larval control methods in construction settings. CONCLUSION: Implementing effective mosquito control, including knowledge and practice on mosquito control together with vector control, is highly required to suppress the expanding mosquito population. It is recommended that employers provide continuous mosquito control education and training to their employees and reward them with incentives, while employees should comply with the guidelines set by their employers to ensure successful mosquito control and reduce the spread of mosquito-borne diseases in the construction industry.


Assuntos
Indústria da Construção , Controle de Mosquitos , Controle de Mosquitos/métodos , Humanos , Animais , Malária/prevenção & controle , Malária/epidemiologia , Culicidae/fisiologia , Mosquitos Vetores/fisiologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde
8.
Parasit Vectors ; 17(1): 216, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734639

RESUMO

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


Assuntos
Culicidae , Código de Barras de DNA Taxonômico , Complexo IV da Cadeia de Transporte de Elétrons , Mosquitos Vetores , Animais , Croácia , Mosquitos Vetores/genética , Mosquitos Vetores/classificação , Mosquitos Vetores/anatomia & histologia , Culicidae/classificação , Culicidae/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Anopheles/genética , Anopheles/classificação , Filogenia , Biblioteca Gênica
9.
PLoS Negl Trop Dis ; 18(5): e0012162, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38709836

RESUMO

West Nile virus (WNV) is a vector-borne flavivirus that causes an increasing number of human and equine West Nile fever cases in Europe. While the virus has been present in the Mediterranean basin and the Balkans since the 1960s, recent years have witnessed its northward expansion, with the first human cases reported in Germany in 2018 and the Netherlands in 2020. WNV transmission and amplification within mosquitoes are temperature-dependent. This study applies a mathematical modelling approach to assess the conditions under which WNV circulation occurs based on the proportion of mosquito bites on WNV-competent birds (dilution), vector-host ratios, mosquito season length and the observed daily temperature data. We modelled five distinct European regions where previous WNV circulation has been observed within the Netherlands, Germany, Spain, Italy, and Greece. We observed that the number of days in which the basic reproduction number (R0) is above one, increased over the last 40 years in all five regions. In the Netherlands, the number of days in which the R0 is above one, is 70% lower than in Spain. The temperature in Greece, Spain and Italy allowed for circulation under low vector-host ratios, and at a high dilution. On the other hand in the Netherlands and Germany, given the observed daily temperature, the thresholds for circulation requires a lower dilution and higher vector-host ratios. For the Netherlands, a short window of introductions between late May and mid-June would result in detectable outbreaks. Our findings revealed that the temperate maritime climate of the Netherlands allows WNV circulation primarily during warmer summers, and only under high vector-host ratios. This research contributes valuable insights into the dynamic relationship between temperature, vector properties, and WNV transmission, offering guidance for proactive strategies in addressing this emerging health threat in Europe.


Assuntos
Mosquitos Vetores , Estações do Ano , Temperatura , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Febre do Nilo Ocidental/transmissão , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Animais , Vírus do Nilo Ocidental/fisiologia , Vírus do Nilo Ocidental/isolamento & purificação , Europa (Continente)/epidemiologia , Humanos , Mosquitos Vetores/virologia , Mosquitos Vetores/fisiologia , Aves/virologia , Países Baixos/epidemiologia , Modelos Teóricos , Culicidae/virologia , Culicidae/fisiologia
10.
Parasit Vectors ; 17(1): 227, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755646

RESUMO

Volatile organic compounds (VOCs) are chemicals emitted as products of cell metabolism, which reflects the physiological and pathological conditions of any living organisms. These compounds play a key role as olfactory cues for arthropod vectors such as mosquitoes, sand flies, and ticks, which act in the transmission of pathogens to many animal species, including humans. Some VOCs may influence arthropod behaviour, e.g., host preference and oviposition site selection for gravid females. Furthermore, deadly vector-borne pathogens such as Plasmodium falciparum and Leishmania infantum are suggested to manipulate the VOCs profile of the host to make them more attractive to mosquitoes and sand fly vectors, respectively. Under the above circumstances, studies on these compounds have demonstrated their potential usefulness for investigating the behavioural response of mosquitoes, sand flies, and ticks toward their vertebrate hosts, as well as potential tools for diagnosis of vector-borne diseases (VBDs). Herein, we provide an account for scientific data available on VOCs to study the host seeking behaviour of arthropod vectors, and their usefulness as attractants, repellents, or tools for an early diagnosis of VBDs.


Assuntos
Culicidae , Psychodidae , Carrapatos , Compostos Orgânicos Voláteis , Animais , Compostos Orgânicos Voláteis/metabolismo , Psychodidae/fisiologia , Psychodidae/parasitologia , Carrapatos/fisiologia , Humanos , Culicidae/fisiologia , Comportamento Animal , Doenças Transmitidas por Vetores/transmissão , Feminino , Mosquitos Vetores/fisiologia , Mosquitos Vetores/parasitologia , Plasmodium falciparum/fisiologia
11.
J Am Mosq Control Assoc ; 40(2): 112-116, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38697617

RESUMO

Among all living beings, mosquitoes account for the highest number of human fatalities. Our study aimed to determine mosquito egg abundance fluctuation from 2015 to 2020, in order to observe which years had the highest mosquito vector densities and whether they coincided with yellow fever virus outbreaks in both human and nonhuman primates. The study area included Atlantic Forest fragments in the state of Rio de Janeiro. Studies from the Diptera Laboratory at FIOCRUZ were selected and compared along a timeline period of the field collections. The highest peak in egg abundance from the analyzed studies was observed from 2016 to 2017 and from 2015 to 2016. The lowest egg abundance was during the collection periods from 2018 to 2019 and 2019 to 2020. The species with the highest abundance throughout all the periods of the studies analyzed was Haemagogus leucocelaenus, representing 87% of all epidemiological species identified. The species with the lowest abundance was Hg. Janthinomys, representing only 1%. Monitoring the population of mosquitoes is imperative for disease surveillance, as the rise in specimens of various vector species directly impacts the occurrence of yellow fever cases in both nonhuman primates and human populations.


Assuntos
Culicidae , Surtos de Doenças , Florestas , Mosquitos Vetores , Febre Amarela , Animais , Brasil/epidemiologia , Febre Amarela/epidemiologia , Febre Amarela/transmissão , Mosquitos Vetores/fisiologia , Culicidae/fisiologia , Humanos , Densidade Demográfica , Dinâmica Populacional , Vírus da Febre Amarela
12.
Parasit Vectors ; 17(1): 201, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711091

RESUMO

PURPOSE: The rising burden of mosquito-borne diseases in Europe extends beyond urban areas, encompassing rural and semi-urban regions near managed and natural wetlands evidenced by recent outbreaks of Usutu and West Nile viruses. While wetland management policies focus on biodiversity and ecosystem services, few studies explore the impact on mosquito vectors. METHODS: Our research addresses this gap, examining juvenile mosquito and aquatic predator communities in 67 ditch sites within a South England coastal marsh subjected to different wetland management tiers. Using joint distribution models, we analyse how mosquito communities respond to abiotic and biotic factors influenced by wetland management. RESULTS: Of the 12 mosquito species identified, Culiseta annulata (Usutu virus vector) and Culex pipiens (Usutu and West Nile virus vector) constitute 47% of 6825 larval mosquitoes. Abundant predators include Coleoptera (water beetles) adults, Corixidae (water boatmen) and Zygoptera (Damselfy) larvae. Models reveal that tier 3 management sites (higher winter water levels, lower agricultural intensity) associated with shade and less floating vegetation are preferred by specific mosquito species. All mosquito species except Anopheles maculipennis s.l., are negatively impacted by potential predators. Culiseta annulata shows positive associations with shaded and turbid water, contrary to preferences of Corixidae predators. CONCLUSIONS: Tier 3 areas managed for biodiversity, characterised by higher seasonal water levels and reduced livestock grazing intensity, provide favourable habitats for key mosquito species that are known vectors of arboviruses, such as Usutu and West Nile. Our findings emphasise the impact of biodiversity-focused wetland management, altering mosquito breeding site vegetation to enhance vector suitability. Further exploration of these trade-offs is crucial for comprehending the broader implications of wetland management.


Assuntos
Biodiversidade , Culicidae , Mosquitos Vetores , Áreas Alagadas , Animais , Mosquitos Vetores/fisiologia , Mosquitos Vetores/virologia , Culicidae/classificação , Culicidae/fisiologia , Culicidae/virologia , Ecossistema , Larva/fisiologia , Estações do Ano , Reino Unido , Culex/fisiologia , Culex/virologia , Culex/classificação , Inglaterra
13.
Front Cell Infect Microbiol ; 14: 1384284, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725451

RESUMO

Japanese spotted fever (JSF) is caused by Rickettsia japonica, mainly vectored by hard ticks. However, whether R. japonica can be transmitted by other arthropods remains unknown. Moreover, it is of interest to investigate whether other Rickettsia species cause spotted fever in endemic areas. In this study, a survey of Rickettsia species was performed in hematophagous arthropods (mosquitoes, tabanids, and ticks) from endemic areas for JSF in Hubei Province, central China. The results showed that the diversity and prevalence of Rickettsia species in mosquitoes are low, suggesting that mosquitoes may not be the vector of zoonotic Rickettsia species. A novel Rickettsia species showed a high prevalence (16.31%, 23/141) in tabanids and was named "Candidatus Rickettsia tabanidii." It is closely related to Rickettsia from fleas and mosquitoes; however, its pathogenicity in humans needs further investigation. Five Rickettsia species were identified in ticks. Rickettsia japonica, the agent of JSF, was detected only in Haemaphysalis longicornis and Haemaphysalis hystricis, suggesting that they may be the major vectors of R. japonica. Notably, two novel species were identified in H. hystricis ticks, one belonging to the spotted fever group and the other potentially belonging to the ancestral group. The latter one named "Candidatus Rickettsia hubeiensis" may provide valuable insight into the evolutionary history of Rickettsia.


Assuntos
Filogenia , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Animais , Rickettsia/isolamento & purificação , Rickettsia/genética , Rickettsia/classificação , China/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/microbiologia , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Carrapatos/microbiologia , Humanos , Artrópodes/microbiologia , DNA Bacteriano/genética , Culicidae/microbiologia , RNA Ribossômico 16S/genética , Doenças Endêmicas , Análise de Sequência de DNA , Sifonápteros/microbiologia
14.
J Vis Exp ; (206)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38738868

RESUMO

Mosquitoes, notorious as the deadliest animals to humans due to their capacity to transmit diseases, pose a persistent challenge to public health. The primary prevention strategy currently in use involves chemical repellents, which often prove ineffective as mosquitoes rapidly develop resistance. Consequently, the invention of new preventive methods is crucial. Such development hinges on a thorough understanding of mosquito biting behaviors, necessitating an experimental setup that accurately replicates actual biting scenarios with controllable testing parameters and quantitative measurements. To bridge this gap, a bio-hybrid atomic force microscopy (AFM) probe was engineered, featuring a biological stinger - specifically, a mosquito labrum - as its tip. This bio-hybrid probe, compatible with standard AFM systems, enables a near-authentic simulation of mosquito penetration behaviors. This method marks a step forward in the quantitative study of biting mechanisms, potentially leading to the creation of effective barriers against vector-borne diseases (VBDs) and opening new avenues in the fight against mosquito-transmitted illnesses.


Assuntos
Culicidae , Microscopia de Força Atômica , Animais , Microscopia de Força Atômica/métodos , Culicidae/fisiologia , Mordeduras e Picadas de Insetos/prevenção & controle
16.
PLoS One ; 19(5): e0301913, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38787834

RESUMO

Small lentic water bodies are important emitters of methane (CH4) and carbon dioxide (CO2), but the processes regulating their dynamics and susceptibility to human-induced stressors are not fully understood. Bioturbation by chironomid larvae has been proposed as a potentially important factor controlling the dynamics of both gases in aquatic sediments. Chironomid abundance can be affected by the application of biocides for mosquito control, such as Bti (Bacillus thuringiensis var. israelensis). Previous research has attributed increases in CH4 and CO2 emissions after Bti application to reduced bioturbation by chironomids. In this study, we separately tested the effect of chironomid bioturbation and Bti addition on CH4 production and emission from natural sediments. In a set of 15 microcosms, we compared CH4 and CO2 emission and production rates with high and low densities of chironomid larvae at the bioturbating stage, and standard and five times (5x) standard Bti dose, with control sediments that contained neither chironomid larvae nor Bti. Regardless of larvae density, chironomid larvae did not affect CH4 nor CO2 emission and production of the sediment, although both rates were more variable in the treatments with organisms. 5xBti dosage, however, led to a more than three-fold increase in CH4 and CO2 production rates, likely stimulated by bioavailable dissolved carbon in the Bti excipient and priming effects. Our results suggest weak effects of bioturbating chironomid larvae on the CH4 and CO2 dynamics in aquatic ecosystems. Furthermore, our results point out towards potential functional implications of Bti for carbon cycling beyond those mediated by changes in the macroinvertebrate community.


Assuntos
Dióxido de Carbono , Chironomidae , Água Doce , Sedimentos Geológicos , Larva , Metano , Animais , Chironomidae/metabolismo , Chironomidae/efeitos dos fármacos , Chironomidae/crescimento & desenvolvimento , Dióxido de Carbono/metabolismo , Dióxido de Carbono/farmacologia , Larva/efeitos dos fármacos , Larva/metabolismo , Metano/metabolismo , Sedimentos Geológicos/química , Bacillus thuringiensis/metabolismo , Desinfetantes/farmacologia , Controle de Mosquitos/métodos , Culicidae/efeitos dos fármacos , Culicidae/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-38791823

RESUMO

In the Americas, wild yellow fever (WYF) is an infectious disease that is highly lethal for some non-human primate species and non-vaccinated people. Specifically, in the Brazilian Atlantic Forest, Haemagogus leucocelaenus and Haemagogus janthinomys mosquitoes act as the major vectors. Despite transmission risk being related to vector densities, little is known about how landscape structure affects vector abundance and movement. To fill these gaps, we used vector abundance data and a model-selection approach to assess how landscape structure affects vector abundance, aiming to identify connecting elements for virus dispersion in the state of São Paulo, Brazil. Our findings show that Hg. leucocelaenus and Hg. janthinomys abundances, in highly degraded and fragmented landscapes, are mainly affected by increases in forest cover at scales of 2.0 and 2.5 km, respectively. Fragmented landscapes provide ecological corridors for vector dispersion, which, along with high vector abundance, promotes the creation of risk areas for WYF virus spread, especially along the border with Minas Gerais state, the upper edges of the Serra do Mar, in the Serra da Cantareira, and in areas of the metropolitan regions of São Paulo and Campinas.


Assuntos
Mosquitos Vetores , Febre Amarela , Brasil , Animais , Febre Amarela/transmissão , Mosquitos Vetores/virologia , Ecossistema , Clima Tropical , Vírus da Febre Amarela , Densidade Demográfica , Culicidae/virologia , Culicidae/fisiologia
18.
Parasitol Res ; 123(5): 218, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38777889

RESUMO

The most widely used attractant to capture adult female mosquitoes is CO2. However, there are also baits available on the market that emit a scent resembling human skin. These baits were specifically designed to attract highly anthropophilic species such as Aedes albopictus and Aedes aegypti. In this study, we compare the effectiveness of CDC traps baited either with CO2 or with a commercial blend simulating skin odor, BG-Sweetscent, for trapping female mosquitoes during daylight hours in an urban reserve in the City of Buenos Aires. We employed a hurdle generalized linear mixed model to analyze trap capture probability and the number of mosquitoes captured per hour, considering the effects of attractant, mosquito species, and their interaction. Traps baited with CO2 captured ten mosquito species, while those baited with BG-Sweetscent captured six in overall significantly lower abundance. The odds of capturing mosquitoes were 292% higher for the CO2-baited traps than for those baited with BG-Sweetscent. No evidence of a combined effect of attractant type and species on female mosquito captures per hour was found. Results indicated that CDC traps baited with CO2 were more effective than those baited with BG-Sweetscent in capturing more mosquito species and a higher number of mosquitoes within each species, even if the species captured with CO2 exhibited a certain level of anthropophilia. This result has practical implications for mosquito surveillance and control in urban natural reserves.


Assuntos
Culicidae , Controle de Mosquitos , Animais , Feminino , Controle de Mosquitos/métodos , Culicidae/fisiologia , Culicidae/classificação , Culicidae/efeitos dos fármacos , Feromônios/farmacologia , Dióxido de Carbono , Cidades , Odorantes/análise , Argentina , Humanos
19.
PLoS Comput Biol ; 20(5): e1012046, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38709820

RESUMO

Genetic surveillance of mosquito populations is becoming increasingly relevant as genetics-based mosquito control strategies advance from laboratory to field testing. Especially applicable are mosquito gene drive projects, the potential scale of which leads monitoring to be a significant cost driver. For these projects, monitoring will be required to detect unintended spread of gene drive mosquitoes beyond field sites, and the emergence of alternative alleles, such as drive-resistant alleles or non-functional effector genes, within intervention sites. This entails the need to distribute mosquito traps efficiently such that an allele of interest is detected as quickly as possible-ideally when remediation is still viable. Additionally, insecticide-based tools such as bednets are compromised by insecticide-resistance alleles for which there is also a need to detect as quickly as possible. To this end, we present MGSurvE (Mosquito Gene SurveillancE): a computational framework that optimizes trap placement for genetic surveillance of mosquito populations such that the time to detection of an allele of interest is minimized. A key strength of MGSurvE is that it allows important biological features of mosquitoes and the landscapes they inhabit to be accounted for, namely: i) resources required by mosquitoes (e.g., food sources and aquatic breeding sites) can be explicitly distributed through a landscape, ii) movement of mosquitoes may depend on their sex, the current state of their gonotrophic cycle (if female) and resource attractiveness, and iii) traps may differ in their attractiveness profile. Example MGSurvE analyses are presented to demonstrate optimal trap placement for: i) an Aedes aegypti population in a suburban landscape in Queensland, Australia, and ii) an Anopheles gambiae population on the island of São Tomé, São Tomé and Príncipe. Further documentation and use examples are provided in project's documentation. MGSurvE is intended as a resource for both field and computational researchers interested in mosquito gene surveillance.


Assuntos
Controle de Mosquitos , Animais , Controle de Mosquitos/métodos , Culicidae/genética , Culicidae/fisiologia , Biologia Computacional/métodos , Tecnologia de Impulso Genético/métodos , Mosquitos Vetores/genética , Aedes/genética , Resistência a Inseticidas/genética , Feminino
20.
ACS Appl Bio Mater ; 7(5): 2862-2871, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38699864

RESUMO

Mosquito-borne viruses are a major worldwide health problem associated with high morbidity and mortality rates and significant impacts on national healthcare budgets. The development of antiviral drugs for both the treatment and prophylaxis of these diseases is thus of considerable importance. To address the need for therapeutics with antiviral activity, a library of heparan sulfate mimetic polymers was screened against dengue virus (DENV), Yellow fever virus (YFV), Zika virus (ZIKV), and Ross River virus (RRV). The polymers were prepared by RAFT polymerization of various acidic monomers with a target MW of 20 kDa (average Mn ∼ 27 kDa by GPC). Among the polymers, poly(SS), a homopolymer of sodium styrenesulfonate, was identified as a broad spectrum antiviral with activity against all the tested viruses and particularly potent inhibition of YFV (IC50 = 310 pM). Our results further uncovered that poly(SS) exhibited a robust inhibition of ZIKV infection in both mosquito and human cell lines, which points out the potential functions of poly(SS) in preventing mosquito-borne viruses associated diseases by blocking viral transmission in their mosquito vectors and mitigating viral infection in patients.


Assuntos
Antivirais , Heparitina Sulfato , Polímeros , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Heparitina Sulfato/química , Heparitina Sulfato/farmacologia , Animais , Humanos , Polímeros/química , Polímeros/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/síntese química , Culicidae/efeitos dos fármacos , Culicidae/virologia , Testes de Sensibilidade Microbiana , Teste de Materiais , Tamanho da Partícula , Linhagem Celular , Estrutura Molecular , Chlorocebus aethiops , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Zika virus/efeitos dos fármacos
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