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1.
BMC Res Notes ; 17(1): 98, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38561830

RESUMO

INTRODUCTION: Dermatobia hominis belongs to the Cuterebridae family, Diptera order; These flies inhabit tropical regions where they are called "fly of death" since the larvae are capable of causing lesions in domestic animals, wild animals including humans, the adult females of D. hominis capture other dipteran to oviposit their eggs on them (phoresis), when hematophagous mosquitoes land on an animal and / or human in order to feed on their blood, the eggs hatch and the larvae immediately penetrate the skin where they will develop to later abandon the host, then in the soil and / or other moist substrate the pupal stage develops, finally new adult flies will emerge from the pupae. OBJECTIVE: The primary goal of the present study was to determine as first record, the presence of Psorophora ferox infested with eggs of Dermatobia hominis, Peru. METHODOLOGY: The present study was carried out in an area of the private reserve "El Vencedor", located within the city of Pucallpa, Ucayali Region-Perú. The area is characterized by being humid tropical, with an average temperature of 26ºC and humidity of 92%, while the annual precipitation is approximately 1570 mm3. The capture method was carried out with the help of a hand net type "butterfly" or also called Jama. RESULTS: A total of 668 mosquitoes of different species were collected, the most abundant being Psorophora albigenu and Psorophora ferox, which represented 88.72% and the least abundant was Culex coronator and Uranotaenia apicalis with 0.15% of the total sample collected. CONCLUSIONS: Within these specimens it was captured a mosquito of the species Ps. ferox with the presence of 8 eggs of D. hominis, of which 3 would have hatched, while in the remaining 5, the larvae would remain inside the eggs.


Assuntos
Culicidae , Dípteros , Animais , Feminino , Adulto , Humanos , Peru , Larva , Pele , Pupa
2.
Parasit Vectors ; 17(1): 168, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566167

RESUMO

BACKGROUND: Mosquitoes inhabiting urban green spaces and cemeteries in Europe represent a crucial facet of public health concern and contribute to the ecological balance. As urbanization intensifies, these areas increasingly serve as vital habitats for various mosquito species, fostering breeding grounds and increasing the risk of disease transmission. METHODS: A study was conducted in the three main cities (inland, coastal, and estuarine) of the Basque Country, northern Spain, to investigate the species composition, abundance, dynamic populations, larval habitats, and host preferences of mosquitoes in urban green spaces and cemeteries. CDC traps and dipping were used to collect mosquitoes for 2 years (2019-2020). RESULTS: A total of 21 mosquito species were identified, with Culex pipiens s.l. being the most abundant and widespread. The three ecological forms of Cx. pipiens were found, and Cx. pipiens pipiens was the most common in both green areas and cemeteries. Morphological identification together with molecular tools identified 65 COI sequences with high homology. The highest species richness was found in the inland city, followed by the coastal city and the estuarine city. Mosquito abundance was significantly higher in green areas compared to cemeteries and in the coastal and estuarine cities compared to the inland city. The investigation of larval breeding sites highlighted the dominance of Cx. pipiens s.l., particularly in semi-artificial ponds, diverse water-holding containers (tyres and buckets) and drainage systems in green areas; in cemeteries, most of the larvae were found in flowerpots and funerary urns. Seasonal activity exhibited variable peaks in mosquito abundance in the different cities, with a notable increase in July or August. Additionally, blood meal analysis revealed that Cx. pipiens s.l. fed on several common urban avian species. CONCLUSIONS: Studies on mosquitoes are essential to understand their role in disease transmission and to design targeted and sustainable management strategies to mitigate the associated risks.


Assuntos
Culex , Culicidae , Animais , Espanha , Parques Recreativos , Cemitérios , Culex/anatomia & histologia , Larva
3.
J Med Entomol ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38518800

RESUMO

Water mites (Hydrachnidia) commonly parasitize mosquitoes; however, the nature of these parasitic interactions remains poorly understood. We sampled mites collected from mosquitoes taken from CDC light traps placed in a botanical garden in Northern Florida from April to November 2022. Mites were found almost exclusively parasitizing the mosquitoes, Anopheles crucians sensu lato (Wiedemann, 1828), Anopheles quadrimaculatus sensu lato (Say, 1824), and Culex erraticus (Dyar and Knab, 1906). All sampled mites were of the genus Arrenurus. Further identification proved to be impossible given the available resources. Seasonality of the mites corresponded with the seasonality of their hosts, with the highest numbers being recorded in May and September. Nomenclature for mite attachment sites on mosquitoes was developed and provided. Mites most commonly attached to the second abdominal segments of all sampled mosquitoes with varied positions around the segment depending on mosquito species. We found significance for the relationship between the abdominal segment mites attached to and what position on the segment mites would take for Cx. erraticus, which indicates a preference of attaching directly underneath the second and fourth abdominal segments. Such a relationship was not found for either Anopheles species.

4.
Gac Sanit ; 2024 Mar 06.
Artigo em Espanhol | MEDLINE | ID: mdl-38519323

RESUMO

The first detection of the tiger mosquito, Aedes (Stegomyia) albopictus (Skuse, 1894), in the autonomous community of Galicia (Spain) is reported. The finding has been possible thanks to the collaboration between citizens, the citizen science application Mosquito Alert and the Rede Galega de Vixilancia de Vectores (ReGaViVec). At the beginning of August 2023, a same person submitted through the app several reports consistent with the tiger mosquito in the municipality of Moaña, in Pontevedra. The ReGaViVec entomological team confirmed the species and conducted vector surveillance in the area by placing traps (11 ovitraps and 3 BG-Sentinel 2 with BG-Lure attractant) with a weekly collection frequency. This finding represents the most northwestern detection of the tiger mosquito in the Iberian Peninsula and shows the crucial role of citizen science in vector surveillance.

5.
Med Vet Entomol ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489505

RESUMO

Mayaro virus (MAYV; Alphavirus: Togaviridae) is an emerging pathogen in Latin America, causing fever and polyarthritis. Sporadic outbreaks of MAYV have occurred in the region, with reported human cases being imported to Europe and North America. Although primarily a risk for those residing in the Amazon basin's tropical forests, recent reports highlight that urbanization would increase the risk of MAYV transmission in Latin America. Urban emergence depends on human susceptibility and the ability of mosquitos like Aedes aegypti  (Linnaeus, 1762) (Diptera: Culicidae) to transmit MAYV. Despite the absence of active MAYV transmission in Argentine, the risk of introduction is substantial due to human movement and the presence of Ae. aegypti in the region. This study aimed to evaluate the susceptibility of different Argentine Ae. aegypti populations to MAYV genotype L (MAYV-L) using dose-response assays and determine barriers to virus infection, dissemination and transmission. Immature mosquito stages were collected in Buenos Aires, Córdoba and Rosario cities. Female Ae. aegypti (F2) were orally infected by feeding on five concentrations of MAYV-L, ranging from 1.0 to 6.0 log10 PFU/mL. Abdomens, legs and saliva were analysed using viral plaque assays. Results revealed that MAYV-L between infection and dissemination were associated with viral doses rather than the population origin. Infection rates varied between 3% and 65%, with a 50% infectious dose >5.5 log10 PFU/mL. Dissemination occurred at 39%, with a 50% dissemination dose of ~6.0 log10 PFU/mL. Dissemination among infected mosquitoes ranged from 60% to 86%, and transmission from disseminated mosquitoes ranged from 11% to 20%. Argentine Ae. aegypti populations exhibited a need for higher viral doses of MAYV-L than those typically found in humans to become infected. In addition, only a small proportion of infected mosquitoes were capable of transmitting the virus. Understanding MAYV transmission in urban areas is crucial for public health interventions.

6.
Life (Basel) ; 14(3)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38541677

RESUMO

Although tropical forests are home to most of the global diversity, they suffer from the most significant knowledge gaps concerning their fauna. Despite its high biodiversity, Brazil is facing an alarming destruction of habitats, with species becoming extinct before they can be discovered or described via science. Therefore, there is an urgent need to expand wildlife inventories, including entomofauna surveys. The present study aimed to analyze the bionomic aspects and the influence of abiotic factors on mosquito fauna whose immature phases develop in two bamboo species, Guadua tagoara and Bambusa vulgaris, in Tijuca National Park, Rio de Janeiro, Brazil. Immatures were collected in 10 artificially drilled bamboo plants, in five stalk internodes per plant, at two sampling points, from March 2022 to March 2023, during 23 collections. A total of 1845 immatures were obtained, 72.14% at sampling point 1 and 27.86% at sampling point 2. Of this, 1162 individuals reached adulthood, belonging to the following species: Culex iridescens, Culex neglectus, Haemagogus leucocelaenus, Orthopodomyia albicosta, Sabethes identicus, Sabethes melanonymphe, Sabethes purpureus, Toxorhynchites bambusicola, Toxorhynchites sp., Trichoprosopon compressum, Trichoprosopon pallidiventer, Wyeomyia arthrostigma, Wyeomyia codiocampa, Wyeomyia lutzi, Wyeomyia oblita, Wyeomyia personata, Wyeomyia serrata, and Wyeomyia sp. The Tijuca National Park is a tourist spot and receives a large number of visitors. Thus, humans can become an accessible food source for mosquitoes in this area, making the species survey critical since important arbovirus vectors have been recorded in Rio de Janeiro.

7.
Res Sq ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38464276

RESUMO

Context: Land use change drives both biodiversity loss and zoonotic disease transmission in tropical countryside landscapes. Developing solutions for protecting countryside biodiversity, public health, and livelihoods requires understanding the scales at which habitat characteristics such as land cover shape biodiversity, especially for arthropods that transmit pathogens. Evidence increasingly shows that species richness for many taxa correlates with local tree cover. Objectives: We investigated whether mosquito species richness, community composition, and presence of disease vector species responded to land use and tree cover - and if so, whether at spatial scales similar to other taxa. Methods: We paired a field survey of mosquito communities in agricultural, residential, and forested lands in rural southern Costa Rica with remotely sensed tree cover data. We compared mosquito community responses to tree cover surrounding survey sites measured across scales, and analyzed community responses to land use and environmental gradients. Results: Tree cover was positively correlated with mosquito species richness, and negatively correlated with the presence of the common invasive dengue vector Aedes albopictus, particularly at small spatial scales of 80 - 200m. Land use predicted community composition and Ae. albopictus presence. Environmental gradients of tree cover, temperature, and elevation explained 7% of species turnover among survey sites. Conclusions: The results suggest that preservation and expansion of tree cover at local scales can protect biodiversity for a wide range of taxa, including arthropods, and also confer protection against disease vector occurrence. The identified spatial range of tree cover benefits can inform land management for conservation and public health protection.

8.
Heliyon ; 10(4): e26477, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404807

RESUMO

The emergence of several zoonotic mosquito-borne pathogens in Europe, including West Nile virus, Sindbis virus and Usutu virus, has emphasised the importance of consistent surveillance. Considerable fieldwork effort is usually needed to detect low-prevalence pathogens in mosquitoes and screening vertebrate hosts and reservoirs is rarely done simultaneously with mosquito sampling. Zoological gardens offer an opportunity for the surveillance of pathogens, mosquitoes, hosts, and reservoirs concurrently; thus, the aim of this study was undertaking integrated surveillance for mosquito-borne pathogens of wild birds and mosquitoes in Chester Zoo (Cheshire) in the United Kingdom. Mosquitoes were collected in September 2020 and tested for zoonotic bird-hosted arboviruses (i.e., West Nile virus, Usutu virus and Sindbis virus) using RT-qPCRs. Of the 3316 mosquitoes trapped, 98% were identified as Culex spp. The average minimum prevalence of the viruses found in the literature was used to calculate the sample size needed for detecting these viruses with 99% confidence. The testing of 2878 Culex females found no evidence of presence of the three viruses. Significant differences were found in mosquito abundance per sampling site and collection date; furthermore, important sources of immature and resting mosquitoes were found near aviaries. Eighteen wild birds belonging to 11 species were found dead in the zoo from May to December 2020 and were RT-qPCR tested for West Nile virus and Usutu virus; all samples resulted negative for viral infection. It is unlikely that these viruses were present in the zoo during the sampling period; however, since they circulate in Europe and Usutu virus has been isolated in the United Kingdom and may overwinter here, continued monitoring of mosquitoes and wild birds is recommended as virus introduction and dissemination are possible. This study highlights the importance of regular and integrated arboviral surveillance of zoonotic pathogens in zoos providing baseline information to that end.

9.
J Insect Sci ; 24(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38367014

RESUMO

Body mass underpins many ecological processes at the level of individuals, populations, and communities. Often estimated in arthropods from linear morphological traits such as body length or head width, these relationships can vary even between closely related taxa. Length-mass relationships of mosquito (Diptera: Culicidae) larvae are poorly known despite the importance of this family to disease and aquatic ecology. To fill this gap, we measured ontogenetic changes in linear traits (body length, head width, and thorax width) and dry and wet masses and estimated length- and width-mass relationships in larvae of 3 culicid species inhabiting different niches: the tropical Aedes albopictus (Skuse, 1894), the temperate Culex pipiens (Linnaeus, 1758), and the snowmelt Ochlerotatus punctor (Kirby, 1837). We compared our results with published length-mass allometries of other aquatic dipteran larvae. We showed that thorax width and body length, but not head width, reliably predicted body mass for our 3 species. The length-mass allometry slopes in aquatic dipterans varied considerably between and within families but were independent of phylogeny, specimen handling, preservation techniques, and data fitting methods. Slope estimates became less precise with decreasing sample size and size range. To obtain reliable estimates of the allometric slopes, we have thus recommended using data on all larval stages for intraspecific allometries and a wide range of species for interspecific allometries. We also cautioned against the indiscriminate use of length-mass allometries obtained for other taxa or collected at lower taxonomic resolutions, e.g., when using length-mass relationships to estimate biomass production at a given site.


Assuntos
Aedes , Culex , Animais , Larva
10.
Protoplasma ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38236420

RESUMO

Some mosquitoes, including species of the genus Toxorhynchites, are known for actively preying on other mosquito larvae, making these predators valuable allies in the fight against vector-borne diseases. A comprehensive understanding of the anatomy and physiology of these potential biological control agents is helpful for the development of effective strategies for controlling vector populations. This includes the antennae, a crucial component in the search for hosts, mating, and selection of oviposition sites. This study utilized scanning electron microscopy to characterize the sensilla on the antennae of adult mosquitoes from two species that are exclusively phytophagous, including Toxorhynchites theobaldi and Toxorhynchites violaceus, as well as Lutzia bigoti, which females are allegedly hematophagous. The types of sensilla in each species were compared, and five basic types of antennal sensilla were identified: trichoid, chaetic, coeloconic, basiconic, and ampullacea. The analysis also found that they were morphologically similar across the three species, regardless of feeding habits or sex. The identification and characterization of basic types of antennal sensilla in T. theobaldi, T. violaceus, and L. bigoti suggest that these structures, which play a crucial role in the behavior and ecology, have common functions across different mosquito species, despite differences in feeding habits or sex.

11.
Sci Total Environ ; 912: 169443, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38114031

RESUMO

A major component of mosquito's climate change response is their heat tolerance, and any ability to rapidly adjust to extreme environmental conditions through phenotypic plasticity. The excessive use of insecticides for the control of major mosquito species leads to resistant populations, however it is largely unclear if this concurrently impacts thermal stress resistance and their potential to adjust tolerance via phenotypic plasticity. Culex pipiens pipiens, Culex pipiens molestus and Aedes albopictus populations obtained from the same region were subjected for 12 generations to selection trials to larvicides Diflubenzuron (DFB) and Bacillus thuringiensis subsp. israelensis (Bti) to develop insecticide resistance. Adults emerging from the selected populations were acclimated at different temperatures and the upper and lower critical thermal limits (CTmax and CTmin) were estimated using dynamic thermal assays. In addition, the supercooling points (SCPs) of non-acclimated adults of resistant and control populations were determined. Our results revealed marked differences in thermal response among the three species, the different acclimation regimes and sexes. Aedes albopictus was more resistant in high than low temperatures compared to both Culex pipiens biotypes. Culex forms responded similarly to heat but differently to cold stress. In both forms, females responded better than males to all thermal stressors. Acclimation at higher and lower temperatures improves CTmax and CTmin values, respectively in both insecticide resistant and control populations of all three species. Overall, selection to insecticides did not affect the thermal performance of adults. Hence, insecticide-resistant mosquito populations perform similarly to untreated ones and are capable of readily adapting to new environmental changes rising concerns regarding their geographic range expansion and disease transmission globally.


Assuntos
Aedes , Culex , Inseticidas , Feminino , Animais , Inseticidas/farmacologia , Resistência a Inseticidas
12.
Curr Biol ; 33(23): 5240-5246.e2, 2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-38052162

RESUMO

Female mosquitoes are among the most notorious blood-feeding insects, sometimes causing severe allergic responses or vectoring a variety of microbial pathogens.1,2 Hematophagy in insects is likely a feeding shift from plant fluids, with the piercing-sucking mouthparts serving as suitable exaptation for piercing vertebrates' skin. The origins of these habits are mired in an often-poor fossil record for many hematophagous lineages,3,4 particularly those of sufficient age, as to give insights into the paleoecological context in which blood feeding first appeared or even to arrive at gross estimates as to when such shifts have occurred. This is certainly the case for mosquitoes, a clade estimated molecularly to date back to the Jurassic.5 The known Mesozoic Culicidae are Late Cretaceous, assigned to the modern Anophelinae or to the extinct Burmaculicinae, sister to other Culicidae, all with mouthparts of a modern type. Here, we report the discovery, in Lower Cretaceous amber from Lebanon, of two conspecific male mosquitoes unexpectedly with piercing mouthparts, armed with denticulate sharp mandibles and laciniae. These male fossils were likely hematophagous. They represent a lineage that diverged earlier than Burmaculicinae, extending the definitive occurrence of the family into the Early Cretaceous and serving to narrow the ghost-lineage gap for mosquitoes.


Assuntos
Culicidae , Fósseis , Animais , Filogenia , Insetos , Comportamento Alimentar , Âmbar
13.
J Am Mosq Control Assoc ; 39(4): 288-290, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38078546

RESUMO

A low odor formulation of ultra-low volume (ULV) malathion (Fyfanon EW®) mosquito adulticide was evaluated in the field for its efficacy using caged female Aedes aegypti. Cages were placed in three rows, 30 m apart at 30, 60, and 90 m from the spray line. The product was applied at the manufacturer's suggested operational rate of 0.28 liter/min (9.5 fl oz/min) and at the maximum label rate of 0.37 liter/min (12.6 fl oz/min) with a Guardian 190ES truck mounted ULV sprayer. At 1 h post-treatment for the manufacturer's suggested operational rate, adult mortality ranged from 85% at 30 m to 46% at 90 m (overall average 65.5%). At 24 h post-treatment, mortality was significantly greater at each distance with complete control of caged mosquitoes at 30 m and >95% at 90 m. Overall, 24-h average mortality at this rate was 96.8%. At the maximum label rate, mosquito mortality at 1 h was considerably greater at all distances and ranged from about 89% to 75% with an overall average of 84.3%. At 24 h post-treatment, complete mortality was recorded at all transect distances at this higher rate. In conclusion, our results showed that at 24 h, Fyfanon EW® was considered very effective when applied by ULV truck mounted ground equipment for area-wide control of mosquitoes.


Assuntos
Aedes , Inseticidas , Animais , Feminino , Malation , Odorantes , Controle de Mosquitos/métodos
14.
Parasitol Res ; 123(1): 23, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38072863

RESUMO

Using Pyriproxyfen in controlling Aedes aegypti shows great potential considering its high competence in low dosages. As an endocrine disruptor, temperature can interfere with its efficiency, related to a decrease in larval emergence inhibition in hotter environments. However, previous studies have been performed at constant temperatures in the laboratory, which may not precisely reflect the environmental conditions in the field. The aim of this study was to assess the effect of the fluctuating temperatures in Pyriproxyfen efficiency on controlling Aedes aegypti larvae. We selected maximum and minimum temperatures from the Brazilian Meteorological Institute database from September to April for cities grouped by five regions. Five fluctuating temperatures (17-26; 20-28.5; 23-32.5; 23-30.5; 19.5-31 °C) were applied to bioassays assessing Pyriproxyfen efficiency in preventing adult emergence in Aedes aegypti larvae in five concentrations. In the lowest temperatures, the most diluted Pyriproxyfen treatment (0.0025 mg/L) was efficient in preventing the emergence of almost thrice the larvae than in the hottest temperatures (61% and 21%, respectively, p value = 0.00015). The concentration that inhibits the emergence of 50% of the population was lower than that preconized by the World Health Organization (0.01 mg/L) in all treatments, except for the hottest temperatures, for which we estimated 0.010 mg/L. We concluded that fluctuating temperatures in laboratory bioassays can provide a more realistic result to integrate the strategies in vector surveillance. For a country with continental proportions such as Brazil, considering regionalities is crucial to the rational use of insecticides.


Assuntos
Aedes , Inseticidas , Animais , Larva , Temperatura , Controle de Mosquitos , Mosquitos Vetores , Inseticidas/farmacologia
15.
Heliyon ; 9(12): e22754, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38107319

RESUMO

The present study aimed to investigate the roles of the physicochemical characteristics of larval habitats in biodiversity and other bionomic factors of mosquitoes in Shiraz. The physical parameters of all habitats were recorded separately. The collected mosquito larvae were identified based on morphological characters. The water samples of larval habitats were analyzed for Biochemical Oxygen Demand (BOD, mg/L), Chemical Oxygen Demand (COD, mg/L), pH, alkalinity, turbidity, total hardness (mg/L), Electrical Conductivity (EC, µS/cm), Total Dissolved Solids (TDS, mg/L), Cl2 (mg/L), and water temperature (°C). In addition, three main indices were used for surveying biodiversity. A total of 1229 larvae were collected from April to September 2018 and May to August 2019. Seven medically important mosquito species were identified morphologically. Culex quinquefasciatus and Cx. laticinctus had the highest distribution and abundance. Ecological results showed that the richness and diversity of species were higher and more stable in natural sites than in manmade places. The optimum BOD, COD, alkalinity, TDS, EC, pH, and temperature of water for mosquitoes of the studied areas were 140 mg/L, 360 mg/L, 160 mg/L, 420 mg/L, 840 µS/cm, 8.3, and 24 °C, respectively. Most mosquitoes tended to live in manmade, temporary, and sunny larval habitats with turbid water. The results provided a better understanding of the biology and ecology of mosquitoes as the most important group of disease vectors to humans and animals. Hence, they could be used to apply some safer and more environmentally friendly methods for mosquito control.

16.
J Am Mosq Control Assoc ; 39(4): 281-283, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38108425

RESUMO

Aedes scapularis has recently been detected for the first time in southwestern Florida. During the course of research and surveillance activities by local mosquito control districts in 2020 and 2021, a total of 190 adult females were collected from 14 separate locations in Collier and Lee Counties. To date, Ae. scapularis has been found in 5 counties since its rediscovery in Florida in 2006. Its detection and likely northward expansion into Collier and Lee Counties from the southern Florida Peninsula is in line with ecological niche model predictions that found the environment of the Gulf Coast of southwestern Florida to be highly suitable for the species. Due to its potential ability to transmit both exotic and endemic pathogens such as Everglades virus and Dirofilaria immitis, understanding the range and distribution of Ae. scapularis should be a priority for Florida mosquito control and public health agencies.


Assuntos
Aedes , Alphavirus , Ochlerotatus , Feminino , Animais , Ecossistema , Controle de Mosquitos
17.
J Vector Ecol ; 49(1): 15-27, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38147298

RESUMO

Amazonian savannas are among the most noteworthy landscape components of the coastal plain of French Guiana. Although they cover only 0.22% of the territory, they bring together a large part of the animal and plant diversity of this overseas region of France. This article outlines the results of the first study dedicated to mosquitoes (Diptera: Culicidae) of Amazonian savannas. Samplings were conducted in eight independent savannas evenly distributed along a transect of 170 km on the coastal plain of French Guiana. A total of 50 mosquito species were recorded, which is about 20% of the culicid fauna currently known in French Guiana. Among them, Culex (Melanoconion) organaboensis sp. nov. and Cx. (Mel.) zabanicus sp. nov. are newly described based on both morphological features of the male genitalia and a DNA barcode obtained from type specimens. Diagnostic characters to assist their identification are provided and their placement within the infrasubgeneric classification of the subgenus Melanoconion is discussed.


Assuntos
Culex , Culicidae , Animais , Masculino , Guiana Francesa , Pradaria
18.
Insects ; 14(12)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38132611

RESUMO

Aedes aegypti is a mosquito native to the African continent, which is now widespread in the tropical and subtropical regions of the world. In many regions, it represents a major challenge to public health, given its role in the cycle of transmission of important arboviruses, such as Dengue, Zika, and Chikungunya. Considering the epidemiological importance of Ae. aegypti, the present study sequenced the partial mitochondrial genome of a sample collected in the municipality of Balsas, in the Brazilian state of Maranhão, followed by High Throughput Sequencing and phylogenetic analyses. The mitochondrial sequence obtained here was 15,863 bp long, and contained 37 functional subunits (thirteen PCGs, twenty-two tRNAs and two rRNAs) in addition to a partial final portion rich in A+T. The data obtained here contribute to the enrichment of our knowledge of the taxonomy and evolutionary biology of this prominent disease vector. These findings represent an important advancement in the understanding of the characteristics of the populations of northeastern Brazil and provide valuable insights into the taxonomy and evolutionary biology of this prominent disease vector.

19.
World Allergy Organ J ; 16(11): 100836, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37965096

RESUMO

Background: Mosquito bite is normally associated with mild allergic responses, but severe localized or systemic reactions are also possible. Reliable tools for the diagnosis of mosquito allergy are still unavailable. Here, we investigated the IgE response to 3 potential salivary allergens identified in the saliva of the tiger mosquito Aedes albopictus. Methods: Serum from 55 adult individuals (28 controls and 27 allergic people), were analysed using an in-house Enzyme Linked ImmunoSorbent Assay (ELISA) against the Salivary Gland Extract (SGE) and the recombinant proteins albD7l2 (Aed al 2), albAntigen5-3 (Aed al 13) and albLIPS-2 (Aed al 14). Results: Fifteen of the 27 (56%) individuals having hypersensitive reactions to mosquito bites had IgE serum levels recognizing SGE. Negative sera did not show detectable levels of IgE targeting the SGE from the most common sympatric mosquito Culex pipiens. Among the positive individuals, 2 subjects displayed IgE targeting Aed al 2 (13%), while IgE recognizing Aed al 13 and Aed al 14 were detected in ten (67%) and seven (47%) individuals, respectively. Two sera from non-hypersensitive subjects had detectable levels of IgE targeting Aed al 13, suggesting possible cross-reaction with the homologue salivary proteins of multiple mosquito species or, more generally, of hematophagous insects. Conclusions: Our results indicate that Aed al 13 and Aed al 14 hold the potential to be developed as tools for the diagnosis of allergy to Ae. albopictus bites. Such tools would facilitate epidemiological studies on tiger mosquito allergy in humans and might foster the development of further protein-based assays to investigate cross-species allergies.

20.
Trop Med Infect Dis ; 8(10)2023 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-37888607

RESUMO

The objective of this study was to evaluate ecological aspects of Mansonia species before the construction of hydroelectric plants on the Madeira River, and thus enable the assessment of the impact of these projects on mosquitoes. A total of 199 samplings were carried out between November 2003 and August 2004, using the technique of attraction with protection. Temporal distribution was evaluated from monthly incidence values obtained from the bite index per man/hour. Relative abundance was subsequently calculated to evaluate the spatial distribution of species, according to land use and municipal districts; furthermore, the pattern of hematophagous activity was evaluated from 12-h and 4-h samplings. The data were analyzed according to the negative binomial distribution and generalized linear models to estimate the influence of environmental factors on the presence and abundance of Mansonia. A total of 1479 specimens were collected, distributed among four species-Mansonia titillans (87%), Mansonia humeralis (6.3%), Mansonia amazonensis (6%), and Mansonia indubitans (0.5%), and spatial distribution analysis showed Ma. titillans to be dominant. Hematophagous activity had peaks between 6:00 p.m. and 8:00 p.m. and species incidence was higher during the rainy season and in areas where domestic animals are raised. Therefore, the region studied presented characteristics favorable to the reproduction of Mansonia even before the construction of the hydroelectric plants and after construction, these conditions were enhanced, due to the increase in the availability of breeding sites for immatures and blood sources for females, as a consequence of changes in the environment.

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