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1.
Zootaxa ; 4858(4): zootaxa.4858.4.1, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33056210

RESUMO

Species of Culex (Diptera: Culicidae) belonging to the subgenus Culiciomyia were collected in partially logged areas and in surrounding pristine forest (Talangaye Forest) in the Nguti Subdivision in the South-West Region of Cameroon. Mosquitoes were collected mainly by sweep netting through forest floor vegetation. Morphological species identification of African Culiciomyia relies almost exclusively on the structure of the male genitalia and the shapes of comb scales on the maxillary palpi of males. Other features of males and the habitus of females are largely indistinguishable between the species of this subgenus. In total, seven currently described species and three new species were collected in the forest. The males of the three new species are described and named as Culex apicopilosus Cornel Mayi, sp. n., Culex lanzaroi Cornel Mayi, sp. n. and Culex pseudosubaequalis Cornel Mayi, sp. n. More detailed descriptions of males of the other currently known species that were collected in the Talangaye Forest and pictorial keys to the males of all Afrotropical species of Culiciomyia, including the new species, are provided.


Assuntos
Culex , Culicidae , Animais , Camarões , Feminino , Florestas , Masculino
2.
Zootaxa ; 4789(2): zootaxa.4789.2.12, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-33056442

RESUMO

Sabethes (Sabethoides) glaucodaemon was described for the first time by Dyar Shannon (1925) based on the adult female. Later, descriptions of the male genitalia and parts of the fourth-instar larva and pupa were published by other authors. No one has described the female genitalia or made a complete description of the larva and pupa. The aim of this study was to redescribe Sa. glaucodaemon in the adult stage, including the male and female genitalia, and the pupa and fourth-instar larva. All stages are illustrated. Distinctions from Sa. (Sbo.) tridentatus are discussed.


Assuntos
Culicidae , Animais , Feminino , Genitália Feminina , Genitália Masculina , Larva , Masculino , Pupa
3.
Zootaxa ; 4772(2): zootaxa.4772.2.10, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-33055620

RESUMO

Seven genera and more than 98 species of mosquitoes (Diptera: Culicidae) are found in southwestern Asia (Harbach 1988). The most recent checklist of Iranian mosquitoes includes 69 species representing either seven or 11 genera depending on the classification used for aedines (Azari-Hamidian et al. 2019). Orthopodomyia pulcripalpis (Rondani) was the most recent genus and species to be added to the Iranian mosquito fauna (Azari-Hamidian et al. 2017).


Assuntos
Culicidae , Animais
4.
Zootaxa ; 4830(2): zootaxa.4830.2.4, 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-33056153

RESUMO

Decamyia Dyar is a subgenus of Wyeomyia Theobald with three valid species. Wyeomyia rorotai Senevet, Chabelard Abonnenc, a species originally described rather briefly in the subgenus Dendromyia, is without subgeneric position in the genus. In the present work, we redescribe Wy. rorotai in all life stages and formally define its taxonomic placement in the subgenus Decamyia by combining morphological and molecular analyses based on the mitochondrial cytochrome c oxidase subunit I gene. We also show that Decamyia is a rather homogeneous group of four species, i.e. Wy. ulocoma (Theobald), Wy. pseudopecten Dyar Knab, Wy. felicia Dyar Núñez Tovar and Wy. rorotai, the immature stages of which almost exclusively inhabit the flower bracts of Heliconiaceae.


Assuntos
Culicidae , Heliconiaceae , Animais
5.
Zootaxa ; 4838(4): zootaxa.4838.4.7, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-33056806

RESUMO

The known cicada fauna of the Republic of Trinidad and Tobago is identified. Calyria hyperochelabrys n. sp., Carineta trinidadensis n. sp., and Herrera grammosticta n. sp. are described as new. The first records of Fidicinoides descampsi Boulard Martinelli, 1996, Proarna hilaris (Germar, 1834), Guyalna bogotana (Distant, 1892a), Majeorona aper (Walker, 1850), Taphura boulardi Sanborn, 2011a, Carineta matura Distant, 1892b, and Herrera nigropercula Sanborn, 2020b are provided. The first reports for the genera Guyalna Boulard Martinelli, 1996, Majeorona Distant, 1905d, Calyria Stål, 1862, Carineta Amyot Audinet-Serville, 1843 and Herrera Distant, 1905c and the tribes Parnisini Distant, 1905e and Carinetini Distant, 1905c are represented by the records for the new species and new records. The first records of Proarna hilaris (Germar, 1830) for Anegada, Antigua, Grenada, Canoun Island, Mayreau Island and Union Island in the Grenadines, Little St. James, Little Thatch Island, Montserrat, Mosquito Island, and St. Kitts, Proarna palisoti (Metcalf, 1963a) for Navarro Island, Majeorona aper (Walker, 1850) for Grenada, and Ariasa albimaculosa Sanborn, 2016c for Bonaire are provided to increase the known distributions of these species and the Caribbean fauna. The currently known cicada fauna for Trinidad is increased here to 15 species representing ten genera, four tribes and two subfamilies. Only Quesada gigas (Olivier, 1790) is known currently from Tobago.


Assuntos
Culicidae , Hemípteros , Animais , Trinidad e Tobago
6.
BMC Infect Dis ; 20(1): 790, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33096994

RESUMO

BACKGROUND: Jamestown Canyon virus (JCV) is a mosquito-borne orthobunyavirus that causes acute febrile illness, meningitis, and meningoencephalitis, mainly among adults. JCV is widely distributed in North America and the number of JCV cases in the U.S. has increased in recent years. Therefore, the central nervous system disease caused by JCV can be considered a potentially re-emerging viral disease. However, the seroprevalence of JCV is unknown in Japan. The purpose of this study is to evaluate the seroprevalence of JCV in the Japanese population. METHODS: We used an IgG enzyme-linked immunosorbent assay (IgG-ELISA) with JCV-infected cell-lysates and/or a neutralizing (NT) antibody assay. The cut-off value of IgG-ELISA was determined using IgG-ELISA to analyze serum specimens from 37 healthy Japanese donors. IgG-ELISA was validated by assessing its sensitivity and specificity, using 38 human serum samples previously tested for the presence or absence of antibodies against JCV and snowshoe hare virus (SSHV), in an in-house NT antibody assay conducted by the Public Health Agency of Canada. The seroepidemiological study was performed using IgG-ELISA and NT antibody assay to analyze 246 human serum samples from the serum bank of the National Institute of Infectious Diseases (NIID) in Japan. RESULTS: The cut-off value of IgG-ELISA was determined at 0.20, based on the mean (- 0.075) and standard deviation (0.092) values using Japanese donors' sera. The sensitivity and the specificity of IgG-ELISA determined using 25 JCV-positive and 4 JCV-negative serum samples were 96 and 100%, respectively. Analysis of the 246 Japanese serum samples revealed that no specimen showed a higher value than the cut-off value of IgG-ELISA, and no sample tested positive by the NT antibody assay. CONCLUSIONS: Our results showed that JCV is not circulating significantly in Japan. To the best of our knowledge, this is the first report to demonstrate the seroprevalence of JCV in the general population in Japan.


Assuntos
Anticorpos Antivirais/imunologia , Vírus da Encefalite da Califórnia/imunologia , Encefalite da Califórnia/epidemiologia , Ensaio de Imunoadsorção Enzimática/métodos , Testes de Neutralização/métodos , Adolescente , Adulto , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Culicidae/virologia , Encefalite da Califórnia/virologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Lactente , Recém-Nascido , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Adulto Jovem
7.
Zootaxa ; 4801(1): zootaxa.4801.1.9, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-33056678

RESUMO

The genus Uranotaenia (Diptera: Culicidae) has been well documented in Madagascar where it includes 73 species, 89.4% being endemic. However, one problem is that most species are morphologically similar in the adult stage. Here, 713 Uranotaenia specimens collected in the tropical forests of Anorana and Maromizaha between 2008 and 2014 were examined. Using the dichotomous keys for the Uranotaenia fauna of Madagascar published in 2004, three species were identified: Uranotaenia neireti (220), Ur. alboabdominalis (110) and Ur. mayottensis (28). The other specimens (355) were not identifiable and were classified as Uranotaenia sp1. Using wing morphometry, the four taxa were classified into four morphogroups. Within the Uranotaenia sp1 group, specimens from the Anorana forest and those from the Maromizaha forest overlapped. This result suggests that wing morphometric traits could be a good marker to distinguish Uranotaenia species in Madagascar.


Assuntos
Culicidae , Animais , Madagáscar , Asas de Animais
8.
PLoS One ; 15(10): e0235726, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33006968

RESUMO

Anthropogenic environments provide favorable conditions for some species, which is especially true of mosquitoes that present eclecticism at the moment of choice for the site of oviposition. In the present study, the diversity of mosquitoes was assessed by providing plastic containers, bamboo internodes, and tires in a forest, the forest edge, and peridomicile environments in a rural settlement area. Eighteen sampling points were chosen, delimited by a buffer of 200 m, placed in three environments: forest, forest edge, and peridomicile. In each environment, larvitraps were installed, separated by a minimum distance of 7 m and 1 m from the ground. A total of 10,131 immature mosquitoes of 20 species were collected. The most abundant species was Culex urichii (29.5%), followed by Trichoprosopon digitatum (27.1%), and Cx. (Melanoconion) spp. (10.4%). There was a difference in the composition of immature mosquito populations between larvitraps (p < 0.0005), and the plastic container hosted a greater diversity of species, whereas tires presented a greater abundance of individuals. The forest, forest edge, and peridomicile environments were also different with regard to diversity of immature mosquito populations (p < 0.0010). The forest edge was the environment with the greatest diversity of species, followed by the peridomicile and forest environments. In the forest and peridomicile, plastic container larvitraps had the greatest diversity, whereas the forest edge tire presented the largest number of individuals. Further, tire larvitraps collected the largest number of individuals in all environments. Ten species associated with the bamboo internode and tire were identified. The preference of species for artificial larvitraps, such as the plastic container and tire, even in wild environments was noted. These artificial objects may represent a risk factor for the population living in this region, as all vector species found in the study were present in plastic containers and tires.


Assuntos
Biodiversidade , Culicidae/classificação , Culicidae/fisiologia , Ecossistema , Animais , Brasil , Feminino , Florestas
9.
PLoS Comput Biol ; 16(10): e1008292, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33075052

RESUMO

The lack of effective vaccines for many endemic diseases often forces policymakers to rely on non-immunizing control measures, such as vector control, to reduce the massive burden of these diseases. Controls can have well-known counterintuitive effects on endemic infections, including the honeymoon effect, in which partially effective controls cause not only a greater initial reduction in infection than expected, but also large outbreaks during control resulting from accumulation of susceptibles. Unfortunately, many control measures cannot be maintained indefinitely, and the results of cessation are poorly understood. Here, we examine the results of stopped or failed non-immunizing control measures in endemic settings. By using a mathematical model to compare the cumulative number of cases expected with and without control, we show that deployment of control can lead to a larger total number of infections, counting from the time that control started, than without any control-the divorce effect. This result is directly related to the population-level loss of immunity resulting from non-immunizing controls and is seen in a variety of models when non-immunizing controls are used against an infection that confers immunity. Finally, we examine three control plans for minimizing the magnitude of the divorce effect in seasonal infections and show that they are incapable of eliminating the divorce effect. While we do not suggest stopping control programs that rely on non-immunizing controls, our results strongly argue that the accumulation of susceptibility should be considered before deploying such controls against endemic infections when indefinite use of the control is unlikely. We highlight that our results are particularly germane to endemic mosquito-borne infections, such as dengue virus, both for routine management involving vector control and for field trials of novel control approaches, and in the context of non-pharmaceutical interventions aimed at COVID-19.


Assuntos
Controle de Doenças Transmissíveis/métodos , Doenças Endêmicas/prevenção & controle , Programas de Imunização , Animais , Número Básico de Reprodução , Infecções por Coronavirus/prevenção & controle , Culicidae , Vacinas contra Dengue/uso terapêutico , Política de Saúde , Humanos , Insetos Vetores , Modelos Teóricos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Saúde Pública , Rubéola (Sarampo Alemão)/prevenção & controle , Vacina contra Rubéola/uso terapêutico , Estações do Ano , Dengue Grave/prevenção & controle , Vacinas Virais/uso terapêutico
10.
Chemosphere ; 254: 126779, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957265

RESUMO

Pyrethroids are a class of highly effective, broad-spectrum, less toxic, biodegradable synthetic pesticides. However, despite the extremely wide application of pyrethroids, there are many problems, such as insecticide resistance, lethal/sub-lethal toxicity to mammals, aquatic organisms or other beneficial organisms. The objectives of this review were to cover the main structures, synthesis, steroisomers, mechanisms of action, anti-mosquito activities, resistance, photodegradation and toxicities of pyrethroids. That was to provide a reference for synthesizing or screening novel pyrethroids with low insecticide resistance and low toxicity to beneficial organisms, evaluating the environmental pollution of pyrethroids and its metabolites. Besides, pyrethroids are mainly used for the control of vectors such as insects, and the non-target organisms are mammals, aquatic organisms etc. While maintaining the insecticidal activity is important, its toxic effects on non-target organisms should be also considered. Pyrethroid resistance is present not only in insect mosquitoes but also in environmental microorganisms, which results in anti-pyrethroids resistance (APR) strains. Besides, photodegradation product dibenzofurans is harmful to mammals and environment. Additionally, pyrethroid metabolites may have higher hormonal interference than the parents. Particularly, delivery of pyrethroids in nanoform can reduce the discharge of more toxic substances (such as organic solvents, etc.) to the environment.


Assuntos
Inseticidas/toxicidade , Piretrinas/toxicidade , Animais , Culicidae/efeitos dos fármacos , Resistência a Inseticidas/fisiologia , Inseticidas/química , Inseticidas/metabolismo , Mosquitos Vetores , Fotólise , Piretrinas/química , Piretrinas/metabolismo
11.
Arch Virol ; 165(12): 2903-2908, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32894348

RESUMO

A novel orbivirus (genus Orbivirus, family Reoviridae), designated Yonaguni orbivirus (YONOV), was isolated from bovine blood collected on a subtropical island of Japan in 2015. The YONOV genome (20,054 nucleotides in total) has a coding arrangement similar to those of mosquito-borne orbiviruses. YONOV has a close genetic relationship to mosquito-borne orbiviruses, especially to Mobuck virus (MBV), which was isolated in North America. However, YONOV and MBV share less than 74% nucleotide sequence identity in the major subcore protein (T2) coding sequence, which satisfies the criterion for species demarcation. It is still uncertain whether YONOV should be assigned to a novel species in the genus Orbivirus.


Assuntos
Genoma Viral , Orbivirus/classificação , Orbivirus/isolamento & purificação , Filogenia , Infecções por Reoviridae/veterinária , Proteínas Virais/genética , Animais , Bovinos/virologia , Culicidae/virologia , Japão , Fases de Leitura Aberta , Infecções por Reoviridae/virologia , Análise de Sequência de DNA
12.
PLoS Negl Trop Dis ; 14(9): e0008621, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32970673

RESUMO

Ross River virus (RRV) is the most common and widespread arbovirus in Australia. Epidemiological models of RRV increase understanding of RRV transmission and help provide early warning of outbreaks to reduce incidence. However, RRV predictive models have not been systematically reviewed, analysed, and compared. The hypothesis of this systematic review was that summarising the epidemiological models applied to predict RRV disease and analysing model performance could elucidate drivers of RRV incidence and transmission patterns. We performed a systematic literature search in PubMed, EMBASE, Web of Science, Cochrane Library, and Scopus for studies of RRV using population-based data, incorporating at least one epidemiological model and analysing the association between exposures and RRV disease. Forty-three articles, all of high or medium quality, were included. Twenty-two (51.2%) used generalised linear models and 11 (25.6%) used time-series models. Climate and weather data were used in 27 (62.8%) and mosquito abundance or related data were used in 14 (32.6%) articles as model covariates. A total of 140 models were included across the articles. Rainfall (69 models, 49.3%), temperature (66, 47.1%) and tide height (45, 32.1%) were the three most commonly used exposures. Ten (23.3%) studies published data related to model performance. This review summarises current knowledge of RRV modelling and reveals a research gap in comparing predictive methods. To improve predictive accuracy, new methods for forecasting, such as non-linear mixed models and machine learning approaches, warrant investigation.


Assuntos
Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/transmissão , Animais , Austrália/epidemiologia , Clima , Culicidae/virologia , Previsões , Humanos , Incidência , Vírus do Rio Ross/isolamento & purificação , Tempo (Meteorologia)
13.
PLoS One ; 15(9): e0235548, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946475

RESUMO

We constructed an electric multi-rotor autonomous unmanned aerial system (UAS) to perform mosquito control activities. The UAS can be equipped with any of four modules for spraying larvicides, dropping larvicide tablets, spreading larvicide granules, and ultra-low volume spraying of adulticides. The larvicide module sprayed 124 µm drops at 591 mL/min over a 14 m swath for a total application rate of 1.6 L/ha. The tablet module was able to repeatedly deliver 40-gram larvicide tablets within 1.1 m of the target site. The granular spreader covered a 6 m swath and treated 0.76 ha in 13 min at an average rate of 1.8 kg/ha. The adulticide module produced 16 µm drops with an average deposition of 2.6 drops/mm2. UAS pesticide applications were made at rates prescribed for conventional aircraft, limited only by the payload capacity and flight time. Despite those limitations, this system can deliver pesticides with much greater precision than conventional aircraft, potentially reducing pesticide use. In smaller, congested environments or in programs with limited resources, UAS may be a preferable alternative to conventional aircraft.


Assuntos
Aeronaves , Culicidae , Monitorização de Parâmetros Ecológicos/instrumentação , Inseticidas/administração & dosagem , Controle de Mosquitos/instrumentação , Animais , Larva
14.
PLoS Med ; 17(9): e1003248, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32946451

RESUMO

BACKGROUND: Two billion long-lasting insecticidal nets (LLINs) have been procured for malaria control. A functional LLIN is one that is present, is in good physical condition, and remains insecticidal, thereby providing protection against vector-borne diseases through preventing bites and killing disease vectors. The World Health Organization (WHO) prequalifies LLINs that remain adequately insecticidal 3 years after deployment. Therefore, institutional buyers often assume that prequalified LLINs are functionally identical with a 3-year lifespan. We measured the lifespans of 3 LLIN products, and calculated their cost per year of functional life, to demonstrate the economic and public health importance of procuring the most cost-effective LLIN product based on its lifespan. METHODS AND FINDINGS: A randomised double-blinded trial of 3 pyrethroid LLIN products (10,571 nets in total) was conducted at 3 follow-up points: 10 months (August-October 2014), 22 months (August-October 2015), and 36 months (October-December 2016) among 3,393 households in Tanzania using WHO-recommended methods. Primary outcome was LLIN functional survival (LLIN present and in serviceable condition). Secondary outcomes were (1) bioefficacy and chemical content (residual insecticidal activity) and (2) protective efficacy for volunteers sleeping under the LLINs (bite reduction and mosquitoes killed). Median LLIN functional survival was significantly different between the 3 net products (p = 0.001): 2.0 years (95% CI 1.7-2.3) for Olyset, 2.5 years (95% CI 2.2-2.8) for PermaNet 2.0 (hazard ratio [HR] 0.73 [95% CI 0.64-0.85], p = 0.001), and 2.6 years (95% CI 2.3-2.8) for NetProtect (HR = 0.70 [95% CI 0.62-0.77], p < 0.001). Functional survival was affected by accumulation of holes, leading to users discarding nets. Protective efficacy also significantly differed between products as they aged. Equivalent annual cost varied between US$1.2 (95% CI $1.1-$1.4) and US$1.5 (95% CI $1.3-$1.7), assuming that each net was priced identically at US$3. The 2 longer-lived nets (PermaNet and NetProtect) were 20% cheaper than the shorter-lived product (Olyset). The trial was limited to only the most widely sold LLINs in Tanzania. Functional survival varies by country, so the single country setting is a limitation. CONCLUSIONS: These results suggest that LLIN functional survival is less than 3 years and differs substantially between products, and these differences strongly influence LLIN value for money. LLIN tendering processes should consider local expectations of cost per year of functional life and not unit price. As new LLIN products come on the market, especially those with new insecticides, it will be imperative to monitor their comparative durability to ensure that the most cost-effective products are procured for malaria control.


Assuntos
Mosquiteiros Tratados com Inseticida/economia , Inseticidas/economia , Controle de Mosquitos/métodos , Animais , Culicidae/efeitos dos fármacos , Vetores de Doenças , Características da Família , Seguimentos , Humanos , Resistência a Inseticidas/efeitos dos fármacos , Mosquiteiros Tratados com Inseticida/tendências , Inseticidas/farmacologia , Malária/prevenção & controle , Controle de Mosquitos/economia , Mosquitos Vetores/efeitos dos fármacos , Piretrinas/farmacologia , Tanzânia/epidemiologia
15.
PLoS Negl Trop Dis ; 14(8): e0008669, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866146

RESUMO

Exposure of adult mosquitoes to pyriproxyfen (PPF), an analog of insect juvenile hormone (JH), has shown promise to effectively sterilize female mosquitoes. However, the underlying mechanisms of the PPF-induced decrease in mosquito fecundity are largely unknown. We performed a comprehensive study to dissect the mode of PPF action in Aedes aegypti mosquitoes. Exposure to PPF prompted the overgrowth of primary follicles in sugar-fed Ae. aegypti females but blocked the development of primary follicles at Christopher's Stage III after blood feeding. Secondary follicles were precociously activated in PPF-treated mosquitoes. Moreover, PPF substantially altered the expression of many genes that are essential for mosquito physiology and oocyte development in the fat body and ovary. In particular, many metabolic genes were differentially expressed in response to PPF treatment, thereby affecting the mobilization and utilization of energy reserves. Furthermore, PPF treatment on the previtellogenic female adults considerably modified mosquito responses to JH and 20-hydroxyecdysone (20E), two major hormones that govern mosquito reproduction. Krüppel homolog 1, a JH-inducible transcriptional regulator, showed consistently elevated expression after PPF exposure. Conversely, PPF upregulated the expression of several key players of the 20E regulatory cascades, including HR3 and E75A, in the previtellogenic stage. After blood-feeding, the expression of these 20E response genes was significantly weaker in PPF-treated mosquitoes than the solvent-treated control groups. RNAi-mediated knockdown of the Methoprene-tolerant (Met) protein, the JH receptor, partially rescued the impaired follicular development after PPF exposure and substantially increased the hatching of the eggs produced by PPF-treated female mosquitoes. Thus, the results suggested that PPF relied on Met to exert its sterilizing effects on female mosquitoes. In summary, this study finds that PPF exposure disturbs normal hormonal responses and metabolism in Ae. aegypti, shedding light on the molecular targets and the downstream signaling pathways activated by PPF.


Assuntos
Aedes/efeitos dos fármacos , Culicidae/efeitos dos fármacos , Inseticidas/farmacologia , Metoprene/metabolismo , Esterilização , Animais , Ecdisterona/farmacologia , Corpo Adiposo/crescimento & desenvolvimento , Feminino , Glicogênio/metabolismo , Proteínas de Insetos/genética , Hormônios Juvenis/farmacologia , Ovário/crescimento & desenvolvimento , Piridinas , Interferência de RNA , Triglicerídeos/metabolismo
16.
PLoS One ; 15(9): e0239478, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986725

RESUMO

Rift Valley fever (RVF) is an arboviral zoonosis that primarily affects ruminants but can also cause illness in humans. The increasing impact of RVF in Africa and Middle East and the risk of expansion to other areas such as Europe, where competent mosquitos are already established, require the implementation of efficient surveillance programs in animal populations. For that, it is pivotal to regularly assess the performance of existing diagnostic tests and to evaluate the capacity of veterinary labs of endemic and non-endemic countries to detect the infection in an accurate and timely manner. In this context, the animal virology network of the MediLabSecure project organized between October 2016 and March 2017 an external quality assessment (EQA) to evaluate the RVF diagnostic capacities of beneficiary veterinary labs. This EQA was conceived as the last step of a training curriculum that included 2 diagnostic workshops that were organized by INIA-CISA (Spain) in 2015 and 2016. Seventeen veterinary diagnostic labs from 17 countries in the Mediterranean and Black Sea regions participated in this EQA. The exercise consisted of two panels of samples for molecular and serological detection of the virus. The laboratories were also provided with positive controls and all the kits and reagents necessary to perform the recommended diagnostic techniques. All the labs were able to apply the different protocols and to provide the results on time. The performance was good in the molecular panel with 70.6% of participants reporting 100% correct results, and excellent in the serological panel with 100% correct results reported by 94.1% of the labs. This EQA provided a good overview of the RVFV diagnostic capacities of the involved labs and demonstrated that most of them were able to correctly identify the virus genome and antibodies in different animal samples.


Assuntos
Febre do Vale de Rift/diagnóstico , Animais , Mar Negro , Culicidae , Europa (Continente) , Genoma Viral , Humanos , Laboratórios , Mar Mediterrâneo , Febre do Vale de Rift/virologia , Vírus da Febre do Vale do Rift/genética , Ruminantes
17.
PLoS Negl Trop Dis ; 14(8): e0008574, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32853274

RESUMO

BACKGROUND: Shifts have occurred in the epidemiological characteristics of Japanese encephalitis (JE), extending from the molecular level to the population level. The aim of this study was to investigate the seroprevalence of JE neutralizing antibodies in healthy populations from different age groups in Zhejiang Province, and to conduct mosquito monitoring to evaluate the infection rate of Japanese encephalitis virus (JEV) among vectors, as well as the molecular characteristics of the E gene of isolated JEV strains. METHODOLOGY/PRINCIPAL FINDINGS: A total of 1190 sera samples were screened by a microseroneutralization test, including 429 infants (28d-11m) and 761 participants (2y-82y). For those under 1 year old, the geometric mean titers (GMTs) of the JE neutralizing antibody was 9.49 at birth and significantly declined as the age of month increased (r = -0.225, P<0.001). For those above 1-year old, seropositive proportions were higher in subjects aged 1-3 years old as well as ≥25 years old (65%-75%), and relatively lower in subjects aged between 4-25 years old (22%-55%). Four or more years after the 2nd dose of JEV-L (first dose administered at 8 months and the second at 2 years of age), the seropositive proportion decreased to 32.5%, and GMTs decreased to 8.08. A total of 87,201 mosquitoes were collected from livestock sheds in 6 surveillance sites during 2015-2018, from which 139 E gene sequences were successfully amplified. The annual infection rate according to bias-corrected maximum likelihood estimation of JEV in Culex tritaeniorhynchus was 1.56, 2.36, 5.65 and 1.77 per 1000, respectively. JEV strains isolated during 2015-2018 all belonged to Genotype I. The E gene of amplified 139 samples differed from the JEV-L vaccine strain at fourteen amino acid residues, including the eight key residues related to virulence and virus attenuation. No divergence was observed at the sites related to antigenicity. CONCLUSIONS/SIGNIFICANCE: Zhejiang Province was at a high risk of JE exposure due to relatively lower neutralizing antibody levels among the younger-aged population and higher infection rates of JEV in mosquitoes. Continuous, timely and full coverage of JE vaccination are essential, as well as the separation of human living areas and livestock shed areas. In addition, annual mosquito surveillance and periodic antibody level monitoring are important for providing evidence for improvement in JE vaccines and immunization schedules.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/virologia , Epidemiologia Molecular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Neutralizantes , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Culex/virologia , Culicidae/virologia , Vírus da Encefalite Japonesa (Espécie)/classificação , Vírus da Encefalite Japonesa (Espécie)/imunologia , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Genes Virais/genética , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Mosquitos Vetores/virologia , Estudos Soroepidemiológicos , Adulto Jovem
18.
PLoS One ; 15(8): e0236920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745085

RESUMO

BACKGROUND: Twenty-seven villages were selected in southwest Burkina Faso to implement new vector control strategies in addition to long lasting insecticidal nets (LLINs) through a Randomized Controlled Trial (RCT). We conducted entomological surveys in the villages during the dry cold season (January 2017), dry hot season (March 2017) and rainy season (June 2017) to describe malaria vectors bionomics, insecticide resistance and transmission prior to this trial. METHODS: We carried out hourly catches (from 17:00 to 09:00) inside and outside 4 houses in each village using the Human Landing Catch technique. Mosquitoes were identified using morphological taxonomic keys. Specimens belonging to the Anopheles gambiae complex and Anopheles funestus group were identified using molecular techniques as well as detection of Plasmodium falciparum infection and insecticide resistance target-site mutations. RESULTS: Eight Anopheles species were detected in the area. Anopheles funestus s.s was the main vector during the dry cold season. It was replaced by Anopheles coluzzii during the dry hot season whereas An. coluzzii and An. gambiae s.s. were the dominant species during the rainy season. Species composition of the Anopheles population varied significantly among seasons. All insecticide resistance mechanisms (kdr-w, kdr-e and ace-1 target site mutations) investigated were found in each members of the An. gambiae complex but at different frequencies. We observed early and late biting phenotypes in the main malaria vector species. Entomological inoculation rates were 2.61, 2.67 and 11.25 infected bites per human per month during dry cold season, dry hot season and rainy season, respectively. CONCLUSION: The entomological indicators of malaria transmission were high despite the universal coverage with LLINs. We detected early and late biting phenotypes in the main malaria vector species as well as physiological insecticide resistance mechanisms. These data will be used to evaluate the impact of complementary tools to LLINs in an upcoming RCT.


Assuntos
Anopheles , Resistência a Inseticidas/genética , Malária Falciparum/transmissão , Mosquitos Vetores/genética , Animais , Anopheles/classificação , Anopheles/genética , Anopheles/parasitologia , Burkina Faso/epidemiologia , Culex/classificação , Culex/genética , Culex/parasitologia , Culicidae/classificação , Culicidae/genética , Culicidae/parasitologia , Ecologia , Genótipo , Humanos , Malária Falciparum/prevenção & controle , Controle de Mosquitos/métodos , Controle de Mosquitos/organização & administração , Mosquitos Vetores/classificação , Mosquitos Vetores/parasitologia , Plasmodium falciparum/isolamento & purificação , Estações do Ano
19.
Am J Trop Med Hyg ; 103(3): 976-985, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32748773

RESUMO

Gene drive technologies represent powerful tools to develop vector control strategies that will complement the current approaches to mitigate arthropod-borne infectious diseases. The characteristics of gene drive technologies have raised additional concerns to those for standard genetically engineered organisms. This generates a need for adaptive governance that has not been met yet because of the rapid rate of progress in gene drive research. For the eventual release of gene drive insects into wild populations, an international governance network would be helpful in guiding scientists, stakeholders, public opinion, and affected communities in its use. We examined the current institutions and governing bodies among various continents that could have an impact on gene drive governance or the potential to adapt to its future use. Possible governance strategies also are proposed that seek to bridge gaps and promote an ethically sound policy framework. Ideally, governance strategies should be developed before or at the same pace as gene drive research to anticipate field releases and maximize their impact as a public health tool. However, this is not likely to happen as it takes years to develop global accords, and some countries may choose to move ahead independently on the new technology.


Assuntos
Culicidae/genética , Tecnologia de Impulso Genético/legislação & jurisprudência , Cooperação Internacional/legislação & jurisprudência , Controle de Mosquitos/legislação & jurisprudência , Mosquitos Vetores/genética , Agricultura/ética , Agricultura/métodos , Animais , Animais Geneticamente Modificados , Pesquisa Biomédica/ética , Pesquisa Biomédica/métodos , Tecnologia de Impulso Genético/ética , Humanos , Controle de Mosquitos/organização & administração , Saúde Pública , Característica Quantitativa Herdável
20.
Proc Biol Sci ; 287(1932): 20201065, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32752986

RESUMO

Temperature is widely known to influence the spatio-temporal dynamics of vector-borne disease transmission, particularly as temperatures vary across critical thermal thresholds. When temperature conditions exhibit such 'transcritical variation', abrupt spatial or temporal discontinuities may result, generating sharp geographical or seasonal boundaries in transmission. Here, we develop a spatio-temporal machine learning algorithm to examine the implications of transcritical variation for West Nile virus (WNV) transmission in the Los Angeles metropolitan area (LA). Analysing a large vector and WNV surveillance dataset spanning 2006-2016, we found that mean temperatures in the previous month strongly predicted the probability of WNV presence in pools of Culex quinquefasciatus mosquitoes, forming distinctive inhibitory (10.0-21.0°C) and favourable (22.7-30.2°C) mean temperature ranges that bound a narrow 1.7°C transitional zone (21-22.7°C). Temperatures during the most intense months of WNV transmission (August/September) were more strongly associated with infection probability in Cx. quinquefasciatus pools in coastal LA, where temperature variation more frequently traversed the narrow transitional temperature range compared to warmer inland locations. This contributed to a pronounced expansion in the geographical distribution of human cases near the coast during warmer-than-average periods. Our findings suggest that transcritical variation may influence the sensitivity of transmission to climate warming, and that especially vulnerable locations may occur where present climatic fluctuations traverse critical temperature thresholds.


Assuntos
Temperatura , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental , Animais , California , Culex , Culicidae , Geografia , Humanos , Los Angeles/epidemiologia , Mosquitos Vetores , Febre do Nilo Ocidental/epidemiologia
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