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1.
Zootaxa ; 5120(1): 53-64, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35391182

RESUMO

A list of corrections as well as the addition of new taxa described since Borkent Dominiak (2020) published a catalog of the Ceratopogonidae of the world is provided. We record a further 70 extant and 7 fossil species and 2 new fossil genera. Beyond the summary provided by Borkent Dominiak (2020, Table 1), the family now includes 6276 extant and 303 fossil species and 23 fossil genera. The number of species names that are nomina dubia is now 181.


Assuntos
Ceratopogonidae , Animais , Fósseis
2.
Zootaxa ; 5091(3): 487-494, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35391234

RESUMO

A new species, Leptoconops (Proleptoconops) chacoensis, is described and photographed from a female collected in a forest area of the Chaco province, Argentina. This is the first record of the subgenus L. (Proleptoconops) Clastrier from the Neotropical region south of Mexico, and the new species is compared with L. (P.) werneri Wirth Atchley from southern USA and Mexico and L. (P.) aviarum from Tajikistan. Besides, the first description of the male of L. (Leptoconops) casali Cavalieri Chiossone is provided, from males collected associated with females in La Rioja and La Pampa provinces, Argentina, and this species is newly recorded from several areas of the country, significantly enlarging its geographical distribution. In addition, a key to Neotropical species of the genus is provided.


Assuntos
Ceratopogonidae , Lepidópteros , Animais , Argentina , Feminino , Masculino
3.
Zootaxa ; 5091(1): 107-130, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35391258

RESUMO

Popularly known as fungus gnats, Mycetophilidae are found in humid environments usually associated with mushrooms and decaying wood. Their immature forms often feed on fungus fruiting bodies. Similar to most bibionomorphans, mycetophilids need due attention concerning their taxonomy and information on their natural history, especially in the Neotropical region. This work describes Monoclona carambeiensis sp. nov., a new species of Monoclona Mik, and furnishes information on the morphology of adults and immatures, besides notes and photographs on the life cycle of the species. Immature forms present on a piece of decaying wood with lichens and fungi were collected from Carambe, Paran, and reared in the laboratory. The emerged adult male was fixed in 80% ethanol. This is the first study describing an immature of a Neotropical species of Monoclona, and also the first record of the genus in the state of Paran, Brazil. This is the third Neotropical species of Mycetophilidae to have its life cycle described, for a fauna with over 1,100 known species.


Assuntos
Agaricales , Ceratopogonidae , Dípteros , Líquens , Animais , Estágios do Ciclo de Vida , Masculino , Nematóceros
4.
Zootaxa ; 5093(4): 445-464, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35391475

RESUMO

Five new Neotropical species in the predaceous midge genus Macrurohelea Ingram Macfie are described: M. bassoi, M. donatoi, M. morenoi, M. sirii, and M. ventanensis, n. spp. and the previously unknown males of M. kuscheli Wirth and M. monotheca Spinelli Grogan are described from specimens collected in several localities of Argentina and Chile. Illustrations and photomicrographs of key features of both sexes are provided as well as a key to all Neotropical species of Macrurohelea.


Assuntos
Ceratopogonidae , Chironomidae , Dípteros , Animais , Argentina , Feminino , Masculino
5.
Parasit Vectors ; 15(1): 69, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236409

RESUMO

BACKGROUND: Proper vector surveillance relies on the ability to identify species of interest accurately and efficiently, though this can be difficult in groups containing cryptic species. Culicoides Latreille is a genus of small biting flies responsible for the transmission of numerous pathogens to a multitude of vertebrates. Regarding pathogen transmission, the C. variipennis species complex is of particular interest in North America. Of the six species within this group, only C. sonorensis Wirth & Jones is a proven vector of bluetongue virus and epizootic hemorrhagic disease virus. Unfortunately, subtle morphological differences, cryptic species, and mitonuclear discordance make species identification in the C. variipennis complex challenging. Recently, single-nucleotide polymorphism (SNP) analysis enabled discrimination between the species of this group; however, this demanding approach is not practical for vector surveillance. METHODS: The aim of the current study was to develop a reliable and affordable way of distinguishing between the species within the C. variipennis complex, especially C. sonorensis. Twenty-five putative microsatellite markers were identified using the C. sonorensis genome and tested for amplification within five species of the C. variipennis complex. Machine learning was then used to determine which markers best explain the genetic differentiation between species. This led to the development of a subset of four and seven markers, which were also tested for species differentiation. RESULTS: A total of 21 microsatellite markers were successfully amplified in the species tested. Clustering analyses of all of these markers recovered the same species-level identification as the previous SNP data. Additionally, the subset of seven markers was equally capable of accurately distinguishing between the members of the C. variipennis complex as the 21 microsatellite markers. Finally, one microsatellite marker (C508) was found to be species-specific, only amplifying in the vector species C. sonorensis among the samples tested. CONCLUSIONS: These microsatellites provide an affordable way to distinguish between the sibling species of the C. variipennis complex and could lead to a better understanding of the species dynamics within this group. Additionally, after further testing, marker C508 may allow for the identification of C. sonorensis with a single-tube assay, potentially providing a powerful new tool for vector surveillance in North America.


Assuntos
Vírus Bluetongue , Ceratopogonidae , Animais , Vírus Bluetongue/genética , Genética Populacional , Insetos Vetores/genética , Repetições de Microssatélites
6.
Viruses ; 14(3)2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35336912

RESUMO

Bluetongue virus (BTV) and African horse sickness virus (AHSV) cause economically important diseases that are currently exotic to the United Kingdom (UK), but have significant potential for introduction and onward transmission. Given the susceptibility of animals kept in zoo collections to vector-borne diseases, a qualitative risk assessment for the introduction of BTV and AHSV to ZSL London Zoo was performed. Risk pathways for each virus were identified and assessed using published literature, animal import data and outputs from epidemiological models. Direct imports of infected animals, as well as wind-borne infected Culicoides, were considered as routes of incursion. The proximity of ongoing disease events in mainland Europe and proven capability of transmission to the UK places ZSL London Zoo at higher risk of BTV release and exposure (estimated as low to medium) than AHSV (estimated as very low to low). The recent long-range expansion of AHSV into Thailand from southern Africa highlights the need for vector competence studies of Palearctic Culicoides for AHSV to assess the risk of transmission in this region.


Assuntos
Vírus da Doença Equina Africana , Doença Equina Africana , Vírus Bluetongue , Bluetongue , Ceratopogonidae , Doença Equina Africana/epidemiologia , Animais , Bluetongue/epidemiologia , Cavalos , Medição de Risco , Ovinos , Reino Unido/epidemiologia
7.
Sci Rep ; 12(1): 3910, 2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35273211

RESUMO

African horse sickness (AHS) is a devastating equine infectious disease. On 17 March 2020, it first appeared in Thailand and threatened all the South-East Asia equine industry security. Therefore, it is imperative to carry out risk warnings of the AHS in China. The maximum entropy algorithm was used to model AHS and Culicoides separately by using climate and non-climate variables. The least cost path (LCP) method was used to analyze the habitat connectivity of Culicoides with the reclassified land cover and altitude as cost factors. The models showed the mean area under the curve as 0.918 and 0.964 for AHS and Culicoides. The prediction result map shows that there is a high risk area in the southern part of China while the habitats of the Culicoides are connected to each other. Therefore, the risk of introducing AHS into China is high and control of the border area should be strengthened immediately.


Assuntos
Vírus da Doença Equina Africana , Doença Equina Africana , Ceratopogonidae , Doença Equina Africana/epidemiologia , Animais , China/epidemiologia , Ecossistema , Cavalos , Insetos Vetores , Medição de Risco
8.
Open Vet J ; 12(1): 114-123, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342732

RESUMO

Background: Bluetongue (BT) is an important infectious, non-contagious, OIE-listed viral disease of domestic and wild ruminants. The disease is transmitted among susceptible animals by a few species of an insect vector in the genus Culicoides. Recently, during the fall of 2020 (September and October), a Bluetongue virus-4 epizootic marked the epidemiological situation in several delegations of Tunisia with clinical cases recorded in sheep and cattle. Aim: Determine the eco-climatic variables most likely associated with delegations reporting BT cases. Methods: A logistic regression model (LRM) was used to examine which eco-climatic variables were most likely associated with delegations reporting BT cases. Results: Based on the LRM, our findings demonstrated that the key factors contributing significantly to BT cases' distribution among delegations in Tunisia included day land surface temperatures (DLST), night land surface temperatures (NLST) and normalized difference vegetation index (NDVI). A positive correlation between sheep distribution and rainfall amounts was demonstrated. Statistical analysis focusing on the most affected delegations during the BT epidemic (the Sahel and the Centre of Tunisia) demonstrated that the epidemic situation seems to be a consequence of the combination of the following environmental parameters: NDVI with values ranging between 0.16 and 0.2, moderate rainfall 2-4-fold above the normal (10-50 mm) and DLST values between 32°C and 34°C in September. Conclusion: These findings suggest and develop a robust and efficient early warning surveillance program in risk areas based on eco-climatic risk factors.


Assuntos
Vírus Bluetongue , Bluetongue , Doenças dos Bovinos , Ceratopogonidae , Doenças dos Ovinos , Animais , Bluetongue/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Insetos Vetores , Ovinos , Doenças dos Ovinos/epidemiologia , Tunísia/epidemiologia
9.
Sci Rep ; 12(1): 1748, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110661

RESUMO

African horse sickness is a vector-borne, non-contagious and highly infectious disease of equines caused by African horse sickness viruses (AHSv) that mainly affect horses. The occurrence of the disease causes huge economic impacts because of its high fatality rate, trade ban and disease control costs. In the planning of vectors and vector-borne diseases like AHS, the application of Ecological niche models (ENM) used an enormous contribution in precisely delineating the suitable habitats of the vector. We developed an ENM to delineate the global suitability of AHSv based on retrospective outbreak data records from 2005 to 2019. The model was developed in an R software program using the Biomod2 package with an Ensemble modeling technique. Predictive environmental variables like mean diurnal range, mean precipitation of driest month(mm), precipitation seasonality (cv), mean annual maximum temperature (oc), mean annual minimum temperature (oc), mean precipitation of warmest quarter(mm), mean precipitation of coldest quarter (mm), mean annual precipitation (mm), solar radiation (kj /day), elevation/altitude (m), wind speed (m/s) were used to develop the model. From these variables, solar radiation, mean maximum temperature, average annual precipitation, altitude and precipitation seasonality contributed 36.83%, 17.1%, 14.34%, 7.61%, and 6.4%, respectively. The model depicted the sub-Sahara African continent as the most suitable area for the virus. Mainly Senegal, Burkina Faso, Niger, Nigeria, Ethiopia, Sudan, Somalia, South Africa, Zimbabwe, Madagascar and Malawi are African countries identified as highly suitable countries for the virus. Besides, OIE-listed disease-free countries like India, Australia, Brazil, Paraguay and Bolivia have been found suitable for the virus. This model can be used as an epidemiological tool in planning control and surveillance of diseases nationally or internationally.


Assuntos
Vírus da Doença Equina Africana , Doença Equina Africana , Ecossistema , Modelos Estatísticos , África/epidemiologia , Doença Equina Africana/epidemiologia , Doença Equina Africana/transmissão , Animais , Ceratopogonidae/virologia , Surtos de Doenças/veterinária , Cavalos , Índia/epidemiologia , Insetos Vetores/virologia , Software , África do Sul/epidemiologia , América do Sul/epidemiologia , Temperatura , Doenças Transmitidas por Vetores/epidemiologia , Doenças Transmitidas por Vetores/transmissão , Doenças Transmitidas por Vetores/veterinária
10.
Sci Rep ; 12(1): 1730, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110675

RESUMO

The inability to distinguish between species can be a serious problem in groups responsible for pathogen transmission. Culicoides biting midges transmit many pathogenic agents infecting wildlife and livestock. In North America, the C. variipennis species complex contains three currently recognized species, only one of which is a known vector, but limited species-specific characters have hindered vector surveillance. Here, genomic data were used to investigate population structure and genetic differentiation within this species complex. Single nucleotide polymorphism data were generated for 206 individuals originating from 17 locations throughout the United States and Canada. Clustering analyses suggest the occurrence of two additional cryptic species within this complex. All five species were significantly differentiated in both sympatry and allopatry. Evidence of hybridization was detected in three different species pairings indicating incomplete reproductive isolation. Additionally, COI sequences were used to identify the hybrid parentage of these individuals, which illuminated discordance between the divergence of the mitochondrial and nuclear datasets.


Assuntos
Ceratopogonidae/genética , DNA Mitocondrial/genética , Evolução Molecular , Especiação Genética , Polimorfismo de Nucleotídeo Único , Simpatria , Animais , Ceratopogonidae/classificação , Genética Populacional , Haplótipos , Especificidade da Espécie
11.
Parasitology ; 149(4): 436-443, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35166204

RESUMO

Climate change effects on host­parasite interactions have been poorly studied in arid or semi-arid habitats. Here, we conducted an experiment aimed to increase the temperature inside European roller Coracias garrulus nest boxes located in a semi-arid habitat on different nest-site types to look for effects on different ectoparasite abundances and nestling growth. Average nest temperature was slightly higher in heated nests than in control nests, although differences were not statistically significant. However, relative humidity was significantly lower at night in heated nests as compared to control nests. The abundance of sand flies, mites and carnid flies was significantly higher in heated, less humid, nests while biting midge abundance was significantly lower in heated nests. Other ectoparasites were not significantly affected by treatment. Relative humidity was high even in heated nests, reaching more than 60%. Sand fly abundance was higher in nests located in sandstone walls, while mite abundance was higher in isolated farmhouses. In addition, sand fly prevalence was higher in nests located in isolated farmhouses and sandstone walls. Heat treatment, nest-site type or ectoparasite abundances did not affect the nestling body mass, wing length or their growth at different nestling ages.


Assuntos
Aves , Ceratopogonidae , Animais , Interações Hospedeiro-Parasita , Umidade , Comportamento de Nidação , Temperatura
12.
Poult Sci ; 101(4): 101690, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35149282

RESUMO

The biting midge Culicoides arakawae is the vector for the parasite Leucocytozoon caulleryi. Birds infected with L. caulleryi develop leucocytozoonosis. Given the food safety concern regarding drug residue in eggs, discovering a natural alternative to antibiotics is a worthy of exploration. Thus, we investigated the effects of the antimalarial herb Artemisia annua on experimentally induced leucocytozoonosis in chickens. We reared C. arakawae in the laboratory. Eggs were cultured, developing into larvae, pupae, and imagoes. Female midges sucked the blood of sick chickens and then were ground into a solution injected into healthy chickens. The control group was given empty capsules daily, whereas the 2 experimental groups were given 40 mg/kg sulfadimethoxine or 0.5 g of A. annua powder. Leucocytozoon gametocytes were detected in chicken blood through Giemsa staining. PCR detected the cytochrome b gene of L. caulleryi in the infected chickens. No significant among-group differences in body weight gain were observed before d 14 postinoculation (P > 0.05). Body weight gain in the control group was significantly lower from day 14 to 28 postinoculation (P < 0.05). After day 14, rectal temperature in the experimental groups decreased significantly compared with that in the control group. Lower rates of pale comb and green feces were observed in the animals receiving treatment from day 0. The experimental groups had a higher recovery rate and recovered earlier than did the control group. By day 31, all the animals had recovered. PCR detected L. caulleryi in the infected chickens with high sensitivity and accuracy. The animals receiving A. annua exhibited increased weight gain and reduced parasite concentrations in the blood. This in turn reduced mortality and the occurrence of pale comb and green feces. The findings are informative for research on leucocytozoonosis.


Assuntos
Artemisia annua , Ceratopogonidae , Doenças das Aves Domésticas , Animais , Peso Corporal , Ceratopogonidae/parasitologia , Galinhas/parasitologia , Feminino , Óvulo , Doenças das Aves Domésticas/induzido quimicamente , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/parasitologia
13.
J Chem Ecol ; 48(4): 359-369, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35107692

RESUMO

Host-derived repellents offer a novel way to reduce disease vector-host interactions, particularly for vectors and nuisance pests where commercial repellents are not available, e.g., Culicoides biting midges. By revising the criteria previously used to identify bioactive volatile organic compounds for Culicoides nubeculosus, we identify (E)-2-hexenal, (E)-2-heptenal, (E)-2-octenal, and (E)-2-nonenal to be differentially present in the headspace odour of cattle hair and to elicit antennal responses in this research model species. A blend of these unsaturated aldehydes elicited an aversive response in C. nubeculosus, as well as a repellent response in three disease vector mosquito species, Aedes aegypti, Culex quinquefasciatus and Anopheles coluzzii, a response that was stronger than that to the commercially available repellents tested (DEET, IR3535, PMD, icaridin, and d-allethrin). Culicoides nubeculosus was behaviourally indifferent to these commercially available repellents tested, except d-allethrin to which it was attracted. The identification of a host-derived repellent odour blend, which reduces the interaction between biting midges extends the array of tools to be used in integrated vector management of these and other disease vectors.


Assuntos
Aedes , Anopheles , Ceratopogonidae , Repelentes de Insetos , Aldeídos/farmacologia , Aletrinas , Animais , Bovinos , Repelentes de Insetos/farmacologia , Mosquitos Vetores
14.
Schweiz Arch Tierheilkd ; 164(1): 66-70, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34983740

RESUMO

INTRODUCTION: Culicoides biting midges unexpectedly arose in Europe as highly efficient vectors of bluetongue virus in the epidemics that started in the Netherlands in 2006. They are known vectors of other orbiviruses, such as African horse sickness (AHSV) and epizootic haemorrhagic disease viruses (EHDV), which are not endemic to Europe. We investigated whether Culicoides occurring in Switzerland at two altitudes (Swiss Plateau, 650 meters above sea level [masl]; and pre-alpine, 2,130 masl) can act as vectors for AHSV and EHDV (two strains each). Biting midges were collected from farms, allowed to feed on virus-spiked blood meals through an artificial membrane in the laboratory and incubated for eight days under two temperature regimes (22 ± 6 °C or 26 ± 6 °C) reflecting a summer day or a hot spell on the Swiss Plateau. Vector competence was assessed from head homogenates by RT-qPCR and virus isolation. Overall, over 15,000 biting midges were exposed to any one of the four viruses. Fully disseminated infections were identified for all four virus strains in 14 individuals (6 C. obsoletus, 8 C. scoticus, as identified by MALDI-TOF mass spectrometry), all originating from the Swiss Plateau, by RT-qPCR. Viable virus could be isolated from 8 of these specimens. Dissemination rates ranged from 1-5%. No viral dissemination was observed in biting midges from the high altitude, predominantly belonging to the species C. grisescens, which were only investigated at the high temperature regime. However, a multivariable logistic regression model revealed no statistical difference in the dissemination rates based on the origin of midges (altitude), virus strain or temperature regime. Thus, AHDV and EHDV transmission is feasible on the Swiss Plateau but unlikely in the pre-alpine area by considering vector abundance. Ways of potential virus introduction include illegal animal movement but also long-distance wind-dispersal of infectious Culicoides.


INTRODUCTION: Les moucherons culicoïdes sont apparus de manière inattendue en Europe en tant que vecteurs très efficaces du virus de la fièvre catarrhale du mouton lors des épidémies qui ont commencé aux Pays-Bas en 2006. Ils sont des vecteurs connus d'autres orbivirus, tels que la peste équine (AHSV) et la maladie à virus hémorragique épizootique (EHDV), qui ne sont pas endémiques en Europe. Nous avons cherché à savoir si les culicoïdes présents en Suisse à deux altitudes (Plateau suisse, 650 mètres au-dessus du niveau de la mer et Préalpes, 2130 mètres au-dessus du niveau de la mer) peuvent agir comme vecteurs pour l'AHSV et l'EHDV (deux souches chacune). Des moucherons piqueurs ont été collectés dans des élevages, laissés se nourrir de repas de sang contaminé par le virus à travers une membrane artificielle en laboratoire et incubés pendant huit jours sous deux régimes de température (22 ± 6 °C ou 26 ± 6 °C) reflétant une journée d'été ou une vague de chaleur sur le plateau suisse. La compétence vectorielle a été évaluée à partir d'homogénats de tête par RT-qPCR et isolement du virus. Dans l'ensemble, plus de 15 000 moucherons piqueurs ont été exposés à l'un des quatre virus. Des infections entièrement disséminées ont été identifiées pour les quatre souches virales chez 14 individus (6 C. obsoletus, 8 C. scoticus, identifiés par spectrométrie de masse MALDI-TOF), tous originaires du plateau suisse, par RT-qPCR. Le virus viable a pu être isolé à partir de 8 de ces échantillons. Les taux de diffusion allaient de 1 à 5 %. Aucune dissémination virale n'a été observée chez les moucherons piqueurs de haute altitude, appartenant majoritairement à l'espèce C. grisescens, qui n'ont été étudiées qu'au régime de haute température. Cependant, un modèle de régression logistique multivariable n'a révélé aucune différence statistique dans les taux de dissémination en fonction de l'origine des moucherons (altitude), de la souche virale ou du régime de température. Ainsi, la transmission de l'AHDV et de l'EHDV est possible sur le plateau suisse mais peu probable dans la zone préalpine en considérant l'abondance des vecteurs. Les voies d'introduction potentielle du virus comprennent les déplacements illégaux d'animaux, mais aussi la dispersion par le vent sur de longues distances de culicoïdes infectieux.


Assuntos
Vírus da Doença Equina Africana , Ceratopogonidae , Vírus da Doença Hemorrágica Epizoótica , Animais , Insetos Vetores , Suíça
15.
J Med Entomol ; 59(1): 240-247, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34632513

RESUMO

Biting midges are widespread in Brazilian natural ecosystems. However, deforestation and other activities that impact the environment are reducing natural habitats where biting midges proliferate. The objective of this study was to verify whether there is variation in the composition, richness, abundance, and seasonality of biting midges between wild and rural environments, in a forest area with intense deforestation. Biting midges were captured using 6 traps installed at an average height of 1.5 m in the peridomicile, intradomicile, and deciduous seasonal forests, once a month from May 2012 to April 2013. In total, 2,182 specimens of 13 species of the genus Culicoides were captured. Species richness was similar in the intradomicile (13 species), forest (12), and peridomicile (11), but species diversity was greater in the peridomicile (H' = 0.803) compared with the intradomicile (H' = 0.717) and forest (H' = 0.687). The order of species dominance varied between the forest (Culicoides paucienfuscatus Barbosa > Culicoides leopodoi Ortiz > Culicoides foxi Ortiz > Culicoides ignacioi Forattini) and peridomicile + intradomicile habitats (C. paucienfuscatus > C. foxi > C. filariferus Hoffman > C. ignacioi). The activity of these dipterans was strongly influenced by meteorological variables, as biting midges are predominant in the rainy season (80.7% of specimens), when higher rainfall, relative humidity, and lower temperatures prevail. The abundance of biting midges was higher in the peridomicile + intradomicile (83.7% of specimens) compared with the degraded forest (16.3%), a result that reflects the loss of forest habitat due to intense and progressive deforestation.


Assuntos
Ceratopogonidae/classificação , Classificação , Animais , Brasil , Ecossistema , Florestas , Insetos Vetores/classificação , População Rural , Estações do Ano
16.
Med Vet Entomol ; 36(1): 113-126, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34811772

RESUMO

Comparative monitoring of the abundance and distribution of Culicoides biting midges (Diptera: Ceratopogonidae), the biological vectors of the causative agents of several diseases of global veterinary importance, will be crucial in determining the risk of disease outbreak and spread. Ultraviolet (UV) suction traps have become the most frequent method used for the monitoring of Culicoides diversity and abundance. The current study compared the trapping efficiency of the two most used UV suction light traps, i.e., the Onderstepoort (OP)- and the Centres for Disease Control trap, for the collection of livestock associated Culicoides species in South Africa. The study confirmed the superiority of the OP trap and indicated a correlation in species composition and age grading results as determine with the two trap types. Substantial variations in the comparative trap efficiency, as found between areas and sites within an area, suggest that a universal conversion factor between the two trap types may not be advisable as it is unclear to what extent species composition and environmental factors may influence the conversion factor. Light traps, independent of trap model, can be considered acceptable for determining the serial comparison of population numbers for seasonal fluctuation and species abundance in distribution surveys.


Assuntos
Ceratopogonidae , Animais , Centers for Disease Control and Prevention, U.S. , Gado , África do Sul , Raios Ultravioleta , Estados Unidos
18.
J Med Entomol ; 59(2): 772-776, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-34971396

RESUMO

Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) play a paramount role in medical and veterinary entomology worldwide, particularly as vectors of pathogens which cause animal diseases. Biting midges are also infamous for the nuisance they provoke to people involved in outdoor activities. Nonetheless, attacks to man by midges from any Culicoides species have not been reported in Italy. An entomological investigation was performed following repeated attacks to man in a nature park near Rome (central Italy). The study area is a natural degassing zone, characterized by widespread hazardous gas emissions of CO2 and H2S, with several water bodies including permanent lakes, ponds, and pools. The biting midge C. riethi Kieffer, 1914 was very active during daytime in the period April-June. The species has been identified as responsible for attacks on people in the area. An in-depth analysis of the extreme environmental conditions revealed the ability of larvae to thrive in several water bodies, characterized by an extremely low pH and a high concentration of sulfates.


Assuntos
Ceratopogonidae , Animais , Cruzamento , Humanos , Insetos Vetores , Itália , Larva , Água
19.
Parasit Vectors ; 14(1): 607, 2021 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-34922599

RESUMO

BACKGROUND: Culicoides kingi and Culicoides oxystoma belong to the Schultzei group of biting midges. These two species are vectors of disease in livestock of economic importance. As described in the literature, morphological identification for discrimination between them is still unclear. However, species-specific identification is necessary to solve taxonomic challenges between species and to understand their roles in disease transmission and epidemiology. This study aims to develop accurate tools to discriminate C. oxystoma from C. kingi using traditional morphometry and polymerase chain reaction-restriction fragment length polymorphism (PCR RFLP) assays for use in developing countries. METHODS: Specimens were collected from the region of Kairouan in central Tunisia. A total of 446 C. oxystoma/C. kingi individuals were identified using traditional morphometric analyses combined with PCR-RFLP of the cytochrome c oxidase subunit I gene. Thirteen morphometric measurements were performed from the head, wings, and abdomen of slide-mounted specimens, and six ratios were calculated between these measurements. Multivariate analyses of the morphometric measurements were explored to identify which variables could lead to accurate species identification. RESULTS: Four variables, namely antennae, wings, spermathecae, and palpus length, were suitable morphometric characteristics to differentiate between the species. Digestion with the SspI restriction enzyme of the PCR product led to good discriminative ability. Molecular procedures and phylogenetic analysis confirmed the efficiency of this simple and rapid PCR-RFLP method. CONCLUSIONS: This study highlights for the first time in Tunisia the presence of C. oxystoma and its discrimination from C. kingi using abdominal measurements and the PCR-RFLP method. This approach could be applied in future epidemiological studies at the national and international levels.


Assuntos
Distribuição Animal , Ceratopogonidae/anatomia & histologia , Ceratopogonidae/genética , DNA/genética , Animais , Ceratopogonidae/classificação , Ceratopogonidae/fisiologia , Genoma , Genômica , Especificidade da Espécie , Tunísia
20.
PLoS Negl Trop Dis ; 15(12): e0010014, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34910720

RESUMO

Biting midges of genus Culicoides (Diptera: Ceratopogonidae) are the vectors of several pathogenic arboviruses and parasites of humans and animals. Several reports have suggested that biting midges might be a potential vector of Leishmania parasites. In this study, we screened for Leishmania and Trypanosoma DNA in biting midges collected from near the home of a leishmaniasis patient in Lamphun province, northern Thailand by using UV-CDC light traps. The identification of biting midge species was based on morphological characters and confirmed using the Cytochrome C oxidase subunit I (COI) gene. The detection of Leishmania and Trypanosoma DNA was performed by amplifying the internal transcribed spacer 1 (ITS1) and small subunit ribosomal RNA (SSU rRNA) genes, respectively. All the amplified PCR amplicons were cloned and sequenced. The collected 223 biting midges belonged to seven species (Culicoides mahasarakhamense, C. guttifer, C. innoxius, C. sumatrae, C. huffi, C. oxystoma, and C. palpifer). The dominant species found in this study was C. mahasarakhamense (47.53%). Leishmania martiniquensis DNA was detected in three samples of 106 specimens of C. mahasarakhamense tested indicating a field infection rate of 2.83%, which is comparable to reported rates in local phlebotomines. Moreover, we also detected Trypanosoma sp. DNA in one sample of C. huffi. To our knowledge, this is the first molecular detection of L. martiniquensis in C. mahasarakhamense as well as the first detection of avian Trypanosoma in C. huffi. Blood meal analysis of engorged specimens of C. mahasarakhamense, C. guttifer, and C. huffi revealed that all specimens had fed on avian, however, further studies of the host ranges of Culicoides are needed to gain a better insight of potential vectors of emerging leishmaniasis. Clarification of the vectors of these parasites is also important to provide tools to establish effective disease prevention and control programs in Thailand.


Assuntos
Ceratopogonidae/parasitologia , Insetos Vetores/parasitologia , Leishmania/genética , Trypanosoma/genética , Animais , Ceratopogonidae/anatomia & histologia , Ceratopogonidae/classificação , DNA de Protozoário/genética , Feminino , Especificidade de Hospedeiro , Humanos , Leishmania/isolamento & purificação , Leishmania/patogenicidade , Técnicas de Amplificação de Ácido Nucleico , Tailândia , Trypanosoma/isolamento & purificação , Trypanosoma/patogenicidade
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