RESUMO
BACKGROUND: Synergists reduce insecticide metabolism in mosquitoes by competing with insecticides for the active sites of metabolic enzymes, such as cytochrome P450s (CYPs). This increases the availability of the insecticide at its specific target site. The combination of both insecticides and synergists increases the toxicity of the mixture. Given the demonstrated resistance to the classical insecticides in numerous Anopheles spp., the use of synergists is becoming increasingly pertinent. Tropical plants synthesize diverse phytochemicals, presenting a repository of potential synergists. METHODS: Extracts prepared from medicinal plants found in Jamaica were screened against recombinant Anopheles gambiae CYP6M2 and CYP6P3, and Anopheles funestus CYP6P9a, CYPs associated with anopheline resistance to pyrethroids and several other insecticide classes. The toxicity of these extracts alone or as synergists, was evaluated using bottle bioassays with the insecticide permethrin. RNA sequencing and in silico modelling were used to determine the mode of action of the extracts. RESULTS: Aqueous extracts of Piper amalago var. amalago inhibited CYP6P9a, CYP6M2, and CYP6P3 with IC50s of 2.61 ± 0.17, 4.3 ± 0.42, and 5.84 ± 0.42 µg/ml, respectively, while extracts of Kalanchoe pinnata, inhibited CYP6M2 with an IC50 of 3.52 ± 0.68 µg/ml. Ethanol extracts of P. amalago var. amalago and K. pinnata displayed dose-dependent insecticidal activity against An. gambiae, with LD50s of 368.42 and 282.37 ng/mosquito, respectively. Additionally, An. gambiae pretreated with K. pinnata (dose: 1.43 µg/mosquito) demonstrated increased susceptibility (83.19 ± 6.14%) to permethrin in a bottle bioassay at 30 min compared to the permethrin only treatment (0% mortality). RNA sequencing demonstrated gene modulation for CYP genes in anopheline mosquitoes exposed to 715 ng of ethanolic plant extract at 24 h. In silico modelling showed good binding affinity between CYPs and the plants' secondary metabolites. CONCLUSION: This study demonstrates that extracts from P. amalago var. amalago and K. pinnata, with inhibitory properties, IC50 < 6.95 µg/ml, against recombinant anopheline CYPs may be developed as natural synergists against anopheline mosquitoes. Novel synergists can help to overcome metabolic resistance to insecticides, which is increasingly reported in malaria vectors.
Assuntos
Anopheles , Inseticidas , Kalanchoe , Extratos Vegetais , Anopheles/efeitos dos fármacos , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Inseticidas/farmacologia , Kalanchoe/química , Sinergistas de Praguicidas/farmacologia , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genéticaRESUMO
The fungi present in the breeding waters of mosquitoes have been scarcely investigated. This work explored the diversity of cultivable fungi present in the breeding sites of the South American malaria vector mosquito Anopheles darlingi. Water samples were collected from four sites located in the municipalities of Coari and São Gabriel da Cachoeira and four different culture media were used for the isolation of fungi. Two-hundred-and-six fungal strains were isolated and morphologically similar fungi were grouped into 30 morphotypes. Their taxonomic identities were assigned by macro and microscopic observations and sequencing of rDNA internal transcribed spacers (ITS1-5.8S-ITS2). Representatives of 26 morphotypes were identified at the genus level, one only at the family level, and three were not identified. The identified morphotypes belong to the phyla, Ascomycota (80.6%), Basidiomycota (11.7%), and Mucoromycota (2.4%), distributed in five classes, ten orders, 25 families, and 26 genera. This study fills a considerable knowledge gap about the fungi present in the breeding sites of An. darlingi mosquitoes.
Assuntos
Anopheles , Fungos , Larva , Animais , Anopheles/microbiologia , Anopheles/genética , Brasil , Larva/microbiologia , Fungos/genética , Fungos/classificação , Fungos/isolamento & purificação , Filogenia , Mosquitos Vetores/microbiologiaRESUMO
The characterization of non-retroviral integrated RNA virus sequences (NIRVS) in mosquitoes has emerged as a significant area of research that could yield insight into virus-host interactions. This study aimed to characterize NIRVS in the Anopheles darlingi reference genome and identify putative transcribed NIRVS in field-collected mosquitoes from Colombia. The An. darlingi reference genome was analyzed to identify and characterize NIRVS by conducting a BLAST query with all the virus sequences previously identified in arthropods available in the NCBI-virus repository. In addition, An. darlingi field-collected mosquitoes were examined for NIRVS using a metatranscriptomic approach. As a result, 44 NIRVS were identified in the An. darlingi genome, constituting integrations of negative single-stranded RNA viruses (ssRNA-) from the families Rhabdoviridae, Chuviridae and Phasmaviridae, and integrations of double-stranded RNA viruses (dsRNA) from the families Partitiviridae and Sedoreoviridae. These NIRVS were not randomly distributed but clustered in specific regions of the genome enriched with BEL/Pao and Ty3/Gypsy long terminal repeat elements. Furthermore, putative NIRVS-like sequences were present in the transcriptomic data from all the Colombian An. darlingi natural populations. This study is significant as it represents the first identification of NIRVS in the most important malaria vector of the Neotropics. The findings help in understanding the intricate relationship between the mosquito and its virome, and the regulation of viruses' mechanisms in the Anopheles genus.
Assuntos
Anopheles , Mosquitos Vetores , Vírus de RNA , Transcriptoma , Animais , Anopheles/virologia , Anopheles/genética , Mosquitos Vetores/virologia , Mosquitos Vetores/genética , Vírus de RNA/genética , Vírus de RNA/classificação , Colômbia , Integração Viral/genética , Malária/transmissão , Malária/virologia , Genoma de InsetoRESUMO
BACKGROUND: Anopheles darlingi is the most efficient vector of malaria parasites in the Neotropics. Nevertheless, the specificities of its larval habitats are still poorly known. OBJECTIVES: Characterize permanent larval habitats, and population dynamics of An. darlingi and other potential vectors in relation to climate, physicochemical variables, insect fauna and malaria cases. METHODS: A 14-month longitudinal study was conducted in Porto Velho, Rondônia, western Brazilian Amazon. Monthly, 21 permanent water bodies were sampled. Immature anophelines and associated fauna were collected, physicochemical characteristics, and climate variables were recorded and analyzed. FINDINGS: Five types of habitats were identified: lagoon, stream, stream combined with lagoon, stream combined with dam, and fishpond. A total of 60,927 anophelines were collected. The most abundant species in all habitats were Anopheles braziliensis and An. darlingi. The highest density was found in the lagoon, while streams had the highest species richness. Abundance was higher during the transition period wet-dry season. There was a lag of respectively four and five months between the peak of rainfall and the Madeira River level and the highest abundance of An. darlingi larvae, which were positively correlated with habitats partially shaded, pH close to neutrality, increase dissolved oxygen and sulphates. MAIN CONCLUSIONS: The present study provides data on key factors defining permanent larval habitats for the surveillance of An. darlingi and other potential vectors as well as a log-linear Negative Binomial model based on immature mosquito abundance and climate variables to predict the increase in the number of malaria cases.
Assuntos
Anopheles , Ecossistema , Larva , Malária , Mosquitos Vetores , Densidade Demográfica , Estações do Ano , Animais , Anopheles/classificação , Anopheles/crescimento & desenvolvimento , Anopheles/fisiologia , Brasil , Mosquitos Vetores/fisiologia , Mosquitos Vetores/classificação , Mosquitos Vetores/crescimento & desenvolvimento , Malária/transmissão , Estudos Longitudinais , Dinâmica PopulacionalRESUMO
The Capivari-Monos Environmental Protection Area (EPA) is located in the southern part of the São Paulo city Green Belt. Since the 1950s, this region has been affected by uncontrolled urban sprawl, resulting in a change in the ecological habits of some vector mosquitoes. Over the last two decades, cases of autochthonous bromeliad malaria associated with the presence of anopheline mosquitoes in the EPA have been recorded. Anopheles cruzii, the primary vector of plasmodia in the region, is abundant and found naturally infected with both Plasmodium vivax and Plasmodium malariae. In light of this, the present study sought to update the catalog of mosquito fauna in this EPA, analyze mosquito diversity among sites with different degrees of conservation and compare species using different collection techniques. Field collections were carried out from March, 2015 to April, 2017. A total of 20,755 specimens were collected, distributed in 106 different taxa representing 16 genera. Analysis of the diversity among the sites based on the Shannon and Simpson indices showed that the most preserved of them had the lowest indices because of the dominance of An. cruzii. The results highlight the increase in the number of different taxa collected as different mosquito collection techniques were included, confirming the importance of using several strategies to ensure adequate sampling of a local mosquito fauna when exploring a greater number of ecotopes. Furthermore, the survey produced the most recent and complete list of mosquito species in the Capivari-Monos EPA, a refuge and shelter for native and introduced mosquito species where new biocenoses, including pathogens, vertebrate hosts, and vectors can form, allowing zoonotic outbreaks in the local human population to occur.
Assuntos
Biodiversidade , Culicidae , Mosquitos Vetores , Animais , Brasil , Culicidae/classificação , Mosquitos Vetores/parasitologia , Mosquitos Vetores/classificação , Anopheles/classificação , Anopheles/fisiologia , Anopheles/parasitologiaRESUMO
Using Illumina NextSeq sequencing and bioinformatics, we identified and characterized thirty-three viral sequences of unsegmented and multipartite viral families in Aedes spp., Culex sp. and Anopheles darlingi female mosquito pools from Porto São Luiz and Pirizal, Alto Pantanal. Seventeen sequences belong to unsegmented viral families, twelve represent putative novel insect-specific viruses (ISVs) within families Chuviridae (3/33; partial genomes) and coding-complete sequences of Xinmoviridae (1/33), Rhabdoviridae (2/33) and Metaviridae (6/33); and five coding-complete sequences of already-known ISVs. Notably, two putative novel rhabdoviruses, Corixo rhabdovirus 1 and 2, were phylogenetically related to Coxipo dielmovirus, but separated from other Alpharhabdovirinae genera, sharing Anopheles spp. as host. Regarding multipartite families, sixteen segments of different putative novel viruses were identified (13 coding-complete segments) within Durnavirales (4/33), Elliovirales (1/33), Hareavirales (3/33) and Reovirales (8/33) orders. Overall, this study describes twenty-eight (28/33) putative novel ISVs and five (5/33) already described viruses using metagenomics approach.
Assuntos
Aedes , Anopheles , Culex , Genoma Viral , Filogenia , Viroma , Animais , Brasil , Feminino , Anopheles/virologia , Viroma/genética , Aedes/virologia , Culex/virologia , Mosquitos Vetores/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Vírus de Insetos/genética , Vírus de Insetos/classificação , Vírus de Insetos/isolamento & purificaçãoRESUMO
BACKGROUND: A treated fabric device for emanating the volatile pyrethroid transfluthrin was recently developed in Tanzania that protected against night-biting Anopheles and Culex mosquitoes for several months. Here perceptions of community end users provided with such transfluthrin emanators, primarily intended to protect them against day-active Aedes vectors of human arboviruses that often attack people outdoors, were assessed in Port-au-Prince, Haiti. METHODS: Following the distribution of transfluthrin emanators to participating households in poor-to-middle class urban neighbourhoods, questionnaire surveys and in-depth interviews of end-user households were supplemented with conventional and Photovoice-based focus group discussions. Observations were assessed synthetically to evaluate user perceptions of protection and acceptability, and to solicit advice for improving and promoting them in the future. RESULTS: Many participants viewed emanators positively and several outlined various advantages over current alternatives, although some expressed concerns about smell, health hazards, bulkiness, unattractiveness and future cost. Most participants expressed moderate to high satisfaction with protection against mosquitoes, especially indoors. Protection against other arthropod pests was also commonly reported, although satisfaction levels were highly variable. Diverse use practices were reported, some of which probably targeted nocturnal Culex resting indoors, rather than Aedes attacking them outdoors during daylight hours. Perceived durability of protection varied: While many participants noted some slow loss over months, others noted rapid decline within days. A few participants specifically attributed efficacy loss to outdoor use and exposure to wind or moisture. Many expressed stringent expectations of satisfactory protection levels, with even a single mosquito bite considered unsatisfactory. Some participants considered emanators superior to fans, bedsheets, sprays and coils, but it is concerning that several preferred them to bed nets and consequently stopped using the latter. CONCLUSIONS: The perspectives shared by Haitian end-users are consistent with those from similar studies in Brazil and recent epidemiological evidence from Peru that other transfluthrin emanator products can protect against arbovirus infection. While these encouraging sociological observations contrast starkly with evidence of essentially negligible effects upon Aedes landing rates from parallel entomological assessments across Haiti, Tanzania, Brazil and Peru, no other reason to doubt the generally encouraging views expressed herein by Haitian end users could be identified.
Assuntos
Ciclopropanos , Fluorbenzenos , Controle de Mosquitos , Haiti , Animais , Humanos , Controle de Mosquitos/métodos , Feminino , Masculino , Inseticidas , Adulto , Mosquitos Vetores , Aedes/efeitos dos fármacos , Pessoa de Meia-Idade , Inquéritos e Questionários , Anopheles/efeitos dos fármacos , Culex/efeitos dos fármacosRESUMO
BACKGROUND: Mexico has experienced a significant reduction in malaria cases over the past two decades. Certification of localities as malaria-free areas (MFAs) has been proposed as a steppingstone before elimination is achieved throughout the country. The Mexican state of Quintana Roo is a candidate for MFA certification. Monitoring the status of insecticide susceptibility of major vectors is crucial for MFA certification. This study describes the susceptibility status of Anopheles albimanus, main malaria vector, from historically important malaria foci in Quintana Roo, using both phenotypic and genotypic approaches. METHODS: Adult mosquito collections were carried out at three localities: Palmar (Municipality of Othon P. Blanco), Buenavista (Bacalar) and Puerto Morelos (Puerto Morelos). Outdoor human-landing catches were performed by pairs of trained staff from 18:00 to 22:00 during 3-night periods at each locality during the rainy season of 2022. Wild-caught female mosquitoes were exposed to diagnostic doses of deltamethrin, permethrin, malathion, pirimiphos-methyl or bendiocarb using CDC bottle bioassays. Mortality was registered at the diagnostic time and recovery was assessed 24 h after exposure. Molecular analyses targeting the Voltage-Gated Sodium Channel (vgsc) gene and acetylcholinesterase (ace-1) gene were used to screen for target site polymorphisms. An SNP analysis was carried out to identify mutations at position 995 in the vgsc gene and at position 280 in the ace-1 gene. RESULTS: A total of 2828 anophelines were collected. The main species identified were Anopheles albimanus (82%) and Anopheles vestitipennis (16%). Mortalities in the CDC bottle bioassay ranged from 99% to 100% for all the insecticides and mosquito species. Sequence analysis was performed on 35 An. albimanus across the three localities; of those, 25 were analysed for vgsc and 10 for ace-1 mutations. All individuals showed wild type alleles. CONCLUSION: The results demonstrated that An. albimanus populations from historical malaria foci in Quintana Roo are susceptible to the main insecticides used by the Ministry of Health.
Assuntos
Anopheles , Resistência a Inseticidas , Inseticidas , Mosquitos Vetores , Animais , Anopheles/genética , Anopheles/efeitos dos fármacos , Inseticidas/farmacologia , Resistência a Inseticidas/genética , México , Feminino , Mosquitos Vetores/genética , Mosquitos Vetores/efeitos dos fármacos , Malária/transmissãoRESUMO
BACKGROUND: Climate change has significant implications on ecosystems. We verified the effects of climate change on the malaria vector Anopheles aquasalis using simulated climate change scenarios (SSCCs). METHODS: An experimental model was designed for SSCCs, which composed of air-conditioned 25 m3 rooms. RESULTS: The wing size was significantly different between SSCCs. A colony of Anopheles aquasalis could not be established in extreme scenarios. CONCLUSIONS: Increases in temperature and CO2 in the atmosphere may modify the global epidemiology of malaria, marking its emergence in currently malaria-free areas.
Assuntos
Anopheles , Malária , Animais , Mosquitos Vetores , Mudança Climática , EcossistemaRESUMO
Vector-borne diseases are a major source of morbidity in Panama. Herein, we describe historical usage patterns of synthetic insecticides to control arthropod disease vectors in this country. We examine the influence of interventions by vector control programs on the emergence of insecticide resistance. Chemical control has traditionally focused on two mosquito species: Anopheles albimanus, a major regional malaria vector, and Aedes aegypti, a historical vector of yellow fever, and current vector of dengue, chikungunya, and Zika. Countrywide populations of An. albimanus depict hyperirritability to organochlorine insecticides administered by indoor residual spraying, although they appear susceptible to these insecticides in bioassays settings, as well as to organophosphate and carbamate insecticides in field tests. Populations of Ae. aegypti show resistance to pyrethroids, particularly in areas near Panama City, but the spread of resistance remains unknown in Ae. aegypti and Aedes albopictus. A One Health approach is needed in Panama to pinpoint the insecticide resistance mechanisms including the frequency of knockdown mutations and behavioral plasticity in populations of Anopheles and Aedes mosquitoes. This information is necessary to guide the sustainable implementation of chemical control strategies and the use of modern vector control technologies such as genetically modified mosquitoes, and endosymbiont Wolbachia-based biological control.
Assuntos
Inseticidas , Controle de Mosquitos , Mosquitos Vetores , Doenças Transmitidas por Vetores , Animais , Humanos , Aedes/efeitos dos fármacos , Anopheles/efeitos dos fármacos , História do Século XX , História do Século XXI , Resistência a Inseticidas , Inseticidas/farmacologia , Controle de Mosquitos/métodos , Mosquitos Vetores/efeitos dos fármacos , Panamá , Doenças Transmitidas por Vetores/prevenção & controleRESUMO
BACKGROUND: In malaria endemic regions of the Peruvian Amazon, rainfall together with river level and breeding site availability drive fluctuating vector mosquito abundance and human malaria cases, leading to temporal heterogeneity. The main variables influencing spatial transmission include location of communities, mosquito behaviour, land use/land cover, and human ecology/behaviour. The main objective was to evaluate seasonal and microgeographic biting behaviour of the malaria vector Nyssorhynchus (or Anopheles) darlingi in Amazonian Peru and to investigate effects of seasonality on malaria transmission. METHODS: We captured mosquitoes from 18:00 to 06:00 h using Human Landing Catch in two riverine (Lupuna, Santa Emilia) and two highway (El Triunfo, Nuevo Horizonte) communities indoors and outdoors from 8 houses per community, during the dry and rainy seasons from February 2016 to January 2017. We then estimated parity rate, daily survival and age of a portion of each collection of Ny. darlingi. All collected specimens of Ny. darlingi were tested for the presence of Plasmodium vivax or Plasmodium falciparum sporozoites using real-time PCR targeting the small subunit of the 18S rRNA. RESULTS: Abundance of Ny. darlingi varied across village, season, and biting behaviour (indoor vs outdoor), and was highly significant between rainy and dry seasons (p < 0.0001). Biting patterns differed, although not significantly, and persisted regardless of season, with peaks in highway communities at ~ 20:00 h in contrast to biting throughout the night (i.e., 18:00-06:00) in riverine communities. Of 3721 Ny. darlingi tested for Plasmodium, 23 (0.62%) were infected. We detected Plasmodium-infected Ny. darlingi in both community types and most (20/23) were captured outdoors during the rainy season; 17/23 before midnight. Seventeen Ny. darlingi were infected with P. vivax, and 6 with P. falciparum. No infected Ny. darlingi were captured during the dry season. Significantly higher rates of parity were detected in Ny. darlingi during the rainy season (average 64.69%) versus the dry season (average 36.91%) and by community, Lupuna, a riverine village, had the highest proportion of parous to nulliparous females during the rainy season. CONCLUSIONS: These data add a seasonal dimension to malaria transmission in peri-Iquitos, providing more evidence that, at least locally, the greatest risk of malaria transmission is outdoors during the rainy season mainly before midnight, irrespective of whether the community was located adjacent to the highway or along the river.
Assuntos
Anopheles , Mordeduras e Picadas , Malária Falciparum , Malária Vivax , Malária , Plasmodium , Animais , Feminino , Humanos , Anopheles/genética , Malária/epidemiologia , Peru/epidemiologia , Mosquitos Vetores , Malária Vivax/epidemiologia , Estações do AnoRESUMO
Light-Emitting Diodes (LEDs) have been effective light sources in attracting Anopheles mosquitoes, but the broad-spectrum white light, even with a wide-ranging application in lighting, have not been evaluated yet. In this study, the white light was field evaluated against the green one in the light trapping of anopheline mosquitoes by using two non-suction Silva traps and two CDC-type suction light traps. Anopheline mosquitoes were captured for two 21-night periods of collecting (2022 and 2023). In the first period, two LEDs were used per Silva trap, but three were used in the second one to increase the luminance/illuminance at traps. A CDC-type suction light trap equipped with an incandescent lamp was used in 2022 and a CDC-type suction light trap equipped with a 6 V-white light (higher luminance/illuminance) in 2023. A total of eight species and 3,289 specimens were captured in both periods. The most frequent species were Anopheles triannulatus s.l., An. goeldii, An. evansae and An. argyritarsis. In 2022, white LEDs were less attractive to anopheline mosquitoes than the other light sources, but without statistical difference among treatments (F = 2.703; P = 0.0752; df = 2). In 2023, even with an increased luminance/illuminance at traps, no statistical difference was found between the two LED-baited Silva traps (F = 6.690; P = 0.0024; df = 2), but rather between the 6 V-white-baited CDC-type suction light trap and green-baited Silva traps. Due to some drawbacks and the lower abundance of individuals caught by using white LEDs, the narrow-banded green LEDs is preferable to white ones for attracting anophelines.
Assuntos
Anopheles , Luz , Controle de Mosquitos , Animais , Anopheles/fisiologia , Anopheles/efeitos da radiação , Controle de Mosquitos/métodos , Controle de Mosquitos/instrumentaçãoRESUMO
BACKGROUND: Information regarding the distribution of Culicidae species in the northeastern region of Brazil is scarce. METHODS: Immatures were collected from approximately four fragments of the Atlantic Forest. RESULTS: This study presents new occurrences of 18 Culicidae species in Pernambuco state: Anopheles kompi, Georgecraigius fluviatilis, Culex bidens, Culex chidesteri, Culex bastagarius, Culex imitator, Mansonia humeralis, Wyeomyia incaudata, Uranotaenia apicalis, Culex mollis, Culex usquatus, Culex dunni, Culex serratimarge, Culex ybarmis, Culex microphyllus, Sabethes purpureus, Wyeomyia pilicauda, and Wyeomyia airosai. The last nine species were also new records for the northeast region. CONCLUSIONS: With the inclusion of these newly recorded species, the total number of mosquitoes documented in Pernambuco state now rises to 94.
Assuntos
Anopheles , Culex , Culicidae , Animais , Brasil , Ecossistema , FlorestasRESUMO
Anopheles darlingi is the primary malaria vector in the Amazon region and is highly susceptible to both Plasmodium vivax and Plasmodium falciparum parasites. Although anopheline mosquitoes may develop melanotic encapsulation in response to Plasmodium parasites, there is no record of An. darlingi exhibiting a melanization response to P. vivax, the main malaria parasite in the Americas. Here, we report the occurrence of P. vivax sporozoite melanization in An. darlingi mosquitoes.
Assuntos
Anopheles , Malária Vivax , Malária , Animais , Humanos , Plasmodium vivax , Anopheles/parasitologia , Esporozoítos , Mosquitos Vetores/parasitologia , Glândulas SalivaresRESUMO
BACKGROUND: Decrease in malaria rates (e.g. incidence and cases) in Latin America maintains this region on track to achieve the goal of elimination. During the last 5 years, three countries have been certified as malaria free. However, the region fails to achieve the goal of 40% reduction on malaria rates and an increase of cases has been reported in some countries, including Ecuador. This scenario has been associated with multiple causes, such as decrease of funding to continue anti-malarial programmes and the development of insecticide resistance of the main malaria vectors. In Ecuador, official reports indicated phenotypic resistance in Aedes aegypti and Anopheles albimanus to deltamethrin and malathion, particularly in the coastal areas of Ecuador, however, information about the mechanisms of resistance have not been yet elucidated. This study aims to evaluate phenotypic response to deltamethrin and its relationship with kdr mutations in An. albimanus from two localities with different agricultural activities in southern coastal Ecuador. METHODS: The CDC bottle assay was carried out to evaluate the phenotypic status of the mosquito's population. Sequencing the voltage gated sodium channel gene (VGSC) sought knockdown mutations (kdr) in codons 1010, 1013 and 1014 associated with resistance. RESULTS: Phenotypic resistance was found in Santa Rosa (63.3%) and suspected resistance in Huaquillas (82.1%); with females presenting a higher median of knockdown rate (83.7%) than males (45.6%). No statistical differences were found between the distributions of knockdown rate for the two localities (p = 0.6048) which indicates no influence of agricultural activity. Although phenotypic resistance was confirmed, genetic analysis demonstrate that this resistance was not related with the kdr mechanism of the VGSC gene because no mutations were found in codons 1010 and 1013, while in codon 1014, 90.6% showed the susceptible sequence (TTG) and 7.3% ambiguous nucleotides (TKK and TYG). CONCLUSIONS: These results highlighted the importance of continuous monitoring of resistance in malaria vectors in Ecuador, particularly in areas that have reported outbreaks during the last years. It is also important to elucidate the mechanism involved in the development of the resistance to PYs to propose alternative insecticides or strategies for vector control in areas where resistance is present.
Assuntos
Anopheles , Inseticidas , Malária , Nitrilas , Animais , Feminino , Anopheles/genética , Códon , Equador , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Mosquitos Vetores/genética , Mutação , MasculinoRESUMO
Malaria is the most important parasitic disease worldwide. In 2019, more than 679,441 cases of malaria were reported in the American region. During this study, Argentina was in malaria pre-elimination autochthonous transmission phase with the aim of being declared as malaria-free country. The aim of this work was to assess the influence of remote sensing spectral indices (NDVI, NDWI) and climatic variables (temperature, relative humidity and precipitation) on the distribution and abundance of Anopheles mosquitoes, in four localities with different degrees of anthropogenic disturbance and with previous malaria cases records located , in a historical malarious area in northeastern of Argentina. Between June 2012 and July 2014, mosquitoes were collected. We collected 535 Anopheles adult mosquitoes. Anopheles strodei s.l. was the most abundant species. The greatest richness, diversity and abundance of species were registered in wild and semi-urban environments. The abundance of Anopheles presented a negative association with relative humidity and mean temperature, but positive with mean maximum temperature. The most important variables determining Anopheles total abundance and distribution were NDWI Index and distance to vegetation. The abundance of An. strodei s.l., was positive associated with water areas whereas the NDVI Index was negatively associated.
Assuntos
Anopheles , Malária , Animais , Argentina , Temperatura , ÁguaRESUMO
Nyssorhynchus (Nyssorhynchus) ibiapabaensis (Sant'Ana & Sallum n. sp.) and Ny. (Nys.) untii (Sant'Ana & Sallum n. sp.) are new species of the Arthuri Complex of the Strodei Subgroup. The new species are described and validated using morphological characters of the male, female, and immature stages. The description of the male, female, fourth-instar larva and pupa of Ny. arthuri (Unti, 1941) and Ny. albertoi (Unti, 1941) are provided for the first time. To avoid nomenclature instability, neotypes are designated for both species. All life stages of Ny. strodei (Root, 1926) employing specimens collected in the Agua Limpa District, Juiz de Fora, Minas Gerais, Brazil are redescribed.
Assuntos
Anopheles , Masculino , Feminino , Animais , Larva/anatomia & histologia , Brasil , Pupa/anatomia & histologiaRESUMO
Background: Mosquito-borne diseases have a significant public health threat worldwide, with arboviruses accounting for a high proportion of infectious diseases and mortality annually. Brazil, in particular, has been suffering outbreaks of diseases transmitted by mosquito viruses, notably those of the Aedes genus, such as dengue, Zika, and chikungunya. Against this background, the São Paulo Zoo is an intriguing ecological niche to explore the virome of mosquitoes, potentially shedding light on the dynamics of arbovirus transmission within a confined setting. Methods: In this study, we conducted a comprehensive metagenomic analysis of mosquitoes collected from diverse habitats within the zoo, focusing on the Aedes, Anopheles, and Culex genera. From 1,039 contigs of viral origin, we identified 229 viral species infecting mosquitoes, with the orders Picornavirales, Nodamuvirales and Sobelivirales being the most prevalent and abundant. The difference in virome composition was primarily driven by mosquito host species rather than specific collection sites or trap height. Results: Despite environmental disparities, the virome remained remarkably uniform across different areas of the zoo, emphasizing the strong association between mosquito species and their viral communities. Furthermore, we identified a core virome shared among mosquito species, highlighting potential cross-species transmission events and underscoring the need for targeted surveillance and control measures. Conclusion: These results contribute to our understanding of the interplay between mosquitoes, the environment, and viruses, providing valuable insights for disease intervention strategies in mosquito-borne diseases.
Assuntos
Metagenômica , Mosquitos Vetores , Viroma , Animais , Brasil , Mosquitos Vetores/virologia , Animais de Zoológico/virologia , Arbovírus/genética , Arbovírus/classificação , Arbovírus/isolamento & purificação , Culicidae/virologia , Aedes/virologia , Anopheles/virologia , Culex/virologia , EcossistemaRESUMO
A malária é um problema mundial de saúde, com 249 milhões de casos de infecção, ocasionando 608 mil mortes no ano de 2022. Causada pelo gênero Plasmodium, são cinco principais espécies causadoras da malária no ser humano, o Plasmodium malariae, Plasmodium ovale, Plasmodium knowlesi, Plasmodium vivax e Plasmodium falciparum sendo os dois últimos responsáveis pelo maior número de casos clínicos e mortes ao redor do mundo, transmitida pelo mosquito fêmea do gênero Anopheles durante o repasto sanguíneo. Sabe-se ainda que eritrócitos infectados por Plasmodium berghei ANKA causam alteração no citoesqueleto de actina, consequentemente levando a hiperpermeabiliade da barreira endotelial. Em experimentos in vitro, a imunofluorescência, foi observada alteração do citoesqueleto de actina em células estimuladas com eritrócitos parasitados por PbA (EP), em contrapartida, aquelas não estimuladas (NE) e estimuladas com eritrócitos não parasitados por PbA (EnP), não mostraram alterações no mesmo. Nos experimentos in vivo, ao observar dados coletados, sendo estes respiratórios (penh e frequência respiratória) e parasitemia coletados no 7º DPI, foi observado um mesmo padrão entre o experimento 1 e o experimento 2. Os animais infectados com 106 de eritrócitos infectados, foram alocados em dois grupos, sendo eles hiperparasitemia (HP) ou síndrome do desconforto respiratório agudo-associado a malária (SDRA/SDRA-MA) e comparados àqueles não infectados (NI). Os animais NI, não apresentam parasitemia, em contrapartida, os animais SDRA, tem maior parasitemia que os HP, visto que estes têm aumento em sua parasitemia após o 12º DPI, e assim seguem aumentando gradativamente até levar os animais a óbito.O penh tem o mesmo padrão que a parasitemia, os NI com penh mais baixa que os HPs e os SDRA, sendo dentre estes, o grupo SDRA o mais elevado. A frequência respiratória, por sua vez se apresenta mais elevada no grupo NI, sendo o grupo SDRAmenor que o HP, um achado tido como normal, visto que os pulmões de animais com SDRA sofrem maior dano que os HPs. Apesar de não apresentar um valor significativo, as imagens de gel SDS-PAGE (WB) mostram maior concentração da Septina 9 nos animais com SDRA em comparação com os HPs e com os NIs. O mesmo é observado na qRT-PCR, mesmo sem significância estatística, o valor mostrado nos gráficos temmaior concentração nos SDRA. Assim, a Septina 9 está presente nas CEPP, e, mesmo sem significância estatística, da mesma forma que está presente nas amostras de tecido pulmonar utilizadas no WB e qT-PCR. É hipotetizado ainda que esta proteína pode ser ativada e assim sofrer alteração em sua localização intracelular
Malaria is a global health problem, with 249 million cases of infection, causing 608 thousand deaths in the year 2022. Caused by the genus Plasmodium, there are five main species that cause malaria in humans, Plasmodium malariae, Plasmodium ovale, Plasmodium knowlesi, Plasmodium vivax and Plasmodium falciparum, the last two being responsible for the largest number of clinical cases and deaths around the world, transmitted by the female mosquito of the genus Anopheles during blood meal. It is also known that erythrocytes infected by Plasmodium berghei ANKA (PbA) cause changes in the actin cytoskeleton, consequently leading to hyperpermeability of the endothelial barrier. In in vitro experiments, immunofluorescence, changes in the actin cytoskeleton were observed in cells stimulated with erythrocytes parasitized by PbA (EP), in contrast, those not stimulated (NE) and stimulated with erythrocytes not parasitized by PbA (EnP), did not show changes the same. In the in vivo experiments, when observing collected data, these being respiratory (penh and respiratory frequency) and parasitemia collected on the 7th DPI, the same pattern was observed between experiment 1 and experiment 2. Animals infected with 106 infected erythrocytes were allocated into two groups, namely hyperparasitemia (HP) or malaria-associated acute respiratory distress syndrome (ARDS/ARDS-MA) and compared to those not infected (NI). NI animals do not present parasitemia, on the other hand, ARDS animals have greater parasitemia than HP animals, as the latter have an increase in their parasitemia after the 12th DPI, and thus continue to gradually increase until the animals die. the same pattern as parasitemia, NI with lower penh than HPs and ARDS, among these, the ARDS group being the highest. The respiratory rate, in turn, is higher in the NI group, with the ARDS group being lower than the HP, a finding considered normal, given that the lungs of animals with ARDS suffer greater damage than the HPs. Despite not showing a significant value, SDS-PAGE (WB) gel images show a higher concentration of Septin 9 in animals with ARDS compared to HPs and NIs. The same is observed in qRT-PCR, even without statistical significance, the value shown in the graphs has a higher concentration in ARDS. Thus, Septin 9 is present in CEPP, and, even without statistical significance, in the same way that it is present in lung tissue samples used in WB and qT-PCR. It is also hypothesized that this protein can be activated and thus undergo changes in its intracellular location
Assuntos
Animais , Masculino , Camundongos , Síndrome do Desconforto Respiratório do Recém-Nascido/patologia , Malária/patologia , Controle Social Formal/classificação , Técnicas In Vitro/métodos , Endotélio , Anopheles/classificaçãoRESUMO
To determine the species composition, relative abundance and seasonal variation of different mosquitoes Genera (Aedes, Anopheles, Armigeres, Culex, and Culiseta) in different habitats the present research work was carried out in Entomology Research Laboratory of The University of Peshawar. Sampling performed from variety of permanent and temporary breeding habitats was carried out on monthly basis from targeted breeding sites for two consecutive years through dipping method. Species diversity in the survey sites was noted. Collection from these seventeen various types of potential larval habitats, yielded a total of 42,430 immature constituting 41,556 larvae and 874 pupae. Among these only 19,651 adult mosquitoes emerged comprising 11,512 female and 8,139 male mosquitoes. 78% (n= 15333) of mosquito larvae were from permanent and 22% (n=4318) were from temporary breeding sites. This study showed that Peshawar valley harbours 15 species from the genera Aedes, Anopheles, Armigeres, Culex and Culiseta. When the density of each species was examined, Culex quinquifasciatus was found to be dominant (79%) and constant in distribution. Among the temporary habitats Aedes albopictus was found as the most prevalent species particularly from tree holes and water cisterns. The highest intensity of mosquitoes was in June (2243 emerged adults) and November (2667 emerged adults) while the lowest was in January (203 emerged adults). A perfect positive correlation (r = +0.8) was found between temperature and population of mosquitoes (df 10 and α 0.05). The species diversity index for mosquitoes remained between 0.12 and 1.76. The Margalef's richness components was noticeably low for bamboo traps (0.2) and fairly high for rice fields, Percolating water and Animal tracks (1.3) which shows the abundance of mosquito species in these habitats. Similarly Pielou's Evenness was highest for bamboo traps (E=1) showing species uniform distribution. Animal tracks were presumed not only the diverse habitat rather also possessed high value for species richness and species evenness. Temperature, rainfall, humidity and other related attributes responsible for species variation and abundance need to be analysed further to pave way for controlling vector species in their oviposition targeted sites.
Para determinar a composição de espécies, abundância relativa e variação sazonal de diferentes gêneros de mosquitos (Aedes, Anopheles, Armigeres, Culex e Culiseta) em diferentes habitats, o presente trabalho foi realizado no Laboratório de Pesquisa em Entomologia da Universidade de Peshawar. A amostragem coletada a partir de uma variedade de habitats de reprodução permanentes e temporários foi realizada mensalmente a partir de locais de reprodução alvo por 2 anos consecutivos através do método de imersão. A diversidade de espécies nos locais de pesquisa foi anotada. A coleta desses 17 tipos diferentes de habitats larvais potenciais rendeu um total de 42.430 imaturos, constituindo 41.556 larvas e 874 pupas. Destes, emergiram apenas 19.651 mosquitos adultos, sendo 11.512 fêmeas e 8.139 machos. 78% (n = 15333) das larvas do mosquito eram de criadouros permanentes e 22% (n = 4318) de criadouros temporários. Este estudo mostrou que o vale de Peshawar abriga 15 espécies dos gêneros Aedes, Anopheles, Armigeres, Culex e Culiseta. Quando a densidade de cada espécie foi examinada, Culex quinquifasciatus foi considerado dominante (79%) e constante na distribuição. Entre os habitats temporários, o Aedes albopictus foi encontrado como a espécie mais prevalente, principalmente em ocos de árvores e cisternas de água. A maior intensidade de mosquitos foi em junho (2.243 adultos emergidos) e novembro (2.667 adultos emergidos), enquanto a menor foi em janeiro (203 adultos emergidos). Uma correlação positiva perfeita (r = +0,8) foi encontrada entre temperatura e população de mosquitos (DF 10 e α 0,05). O índice de diversidade de espécies de mosquitos permaneceu entre 0,12 e 1,76. Os componentes de riqueza de Margalef foram visivelmente baixos para armadilhas de bambu (0,2) e razoavelmente altos para campos de arroz, água percolada e rastros de animais (1,3), o que mostra a abundância de espécies de mosquitos nesses habitats. Da mesma forma, a uniformidade de Pielou foi maior para armadilhas de bambu (E = 1), mostrando distribuição uniforme das espécies. As pegadas de animais foram presumidas não apenas como habitat diverso, mas também possuíam alto valor para riqueza e uniformidade de espécies. Temperatura, chuva, umidade e outros atributos relacionados responsáveis pela variação e abundância das espécies precisam ser analisados mais a fundo para abrir caminho para o controle de espécies de vetores em seus locais de oviposição alvo.