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1.
Nat Commun ; 12(1): 2766, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986255

RESUMO

The escalating global prevalence of arboviral diseases emphasizes the need to improve our understanding of their biology. Research in this area has been hindered by the lack of molecular tools for studying virus-mosquito interactions. Here, we develop an Aedes aegypti cell line which stably expresses Zika virus (ZIKV) capsid proteins in order to study virus-vector protein-protein interactions through quantitative label-free proteomics. We identify 157 interactors and show that eight have potentially pro-viral activity during ZIKV infection in mosquito cells. Notably, silencing of transitional endoplasmic reticulum protein TER94 prevents ZIKV capsid degradation and significantly reduces viral replication. Similar results are observed if the TER94 ortholog (VCP) functioning is blocked with inhibitors in human cells. In addition, we show that an E3 ubiquitin-protein ligase, UBR5, mediates the interaction between TER94 and ZIKV capsid. Our study demonstrates a pro-viral function for TER94/VCP during ZIKV infection that is conserved between human and mosquito cells.


Assuntos
Proteínas do Capsídeo/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Proteína com Valosina/metabolismo , Zika virus/metabolismo , Células A549 , Aedes/virologia , Animais , Capsídeo/metabolismo , Linhagem Celular Tumoral , Retículo Endoplasmático/metabolismo , Humanos , Mapas de Interação de Proteínas , Interferência de RNA , RNA Interferente Pequeno/genética , Proteína com Valosina/genética , Replicação Viral/fisiologia , Zika virus/genética , Infecção por Zika virus/patologia
2.
Nat Commun ; 12(1): 2290, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33863888

RESUMO

Arthropod-borne viruses pose a major threat to global public health. Thus, innovative strategies for their control and prevention are urgently needed. Here, we exploit the natural capacity of viruses to generate defective viral genomes (DVGs) to their detriment. While DVGs have been described for most viruses, identifying which, if any, can be used as therapeutic agents remains a challenge. We present a combined experimental evolution and computational approach to triage DVG sequence space and pinpoint the fittest deletions, using Zika virus as an arbovirus model. This approach identifies fit DVGs that optimally interfere with wild-type virus infection. We show that the most fit DVGs conserve the open reading frame to maintain the translation of the remaining non-structural proteins, a characteristic that is fundamental across the flavivirus genus. Finally, we demonstrate that the high fitness DVG is antiviral in vivo both in the mammalian host and the mosquito vector, reducing transmission in the latter by up to 90%. Our approach establishes the method to interrogate the DVG fitness landscape, and enables the systematic identification of DVGs that show promise as human therapeutics and vector control strategies to mitigate arbovirus transmission and disease.


Assuntos
Antivirais/administração & dosagem , Vírus Defeituosos/genética , Mosquitos Vetores/efeitos dos fármacos , Infecção por Zika virus/tratamento farmacológico , Zika virus/genética , Aedes/efeitos dos fármacos , Aedes/virologia , Animais , Chlorocebus aethiops , Biologia Computacional , Evolução Molecular Direcionada , Modelos Animais de Doenças , Feminino , Aptidão Genética , Genoma Viral/genética , Células HEK293 , Humanos , Camundongos , Controle de Mosquitos/métodos , Mosquitos Vetores/virologia , Fases de Leitura Aberta/genética , RNA Viral/genética , Células Vero , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
3.
Int J Infect Dis ; 105: 595-597, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33713818

RESUMO

Zika virus (ZIKV) is a Flavivirus transmitted by Aedes mosquitoes, and was responsible for a worldwide outbreak between 2013 and 2016. However, no ZIKV outbreak has been described in Southeast Asia since 2017. In this study, we report the first microcephaly case with probable ZIKV infection during pregnancy in Lao People's Democratic Republic.


Assuntos
Aedes/virologia , Surtos de Doenças , Microcefalia/diagnóstico , Infecção por Zika virus/diagnóstico , Zika virus/isolamento & purificação , Adulto , Animais , Ásia Sudeste/epidemiologia , Feminino , Humanos , Recém-Nascido , Laos/epidemiologia , Masculino , Microcefalia/epidemiologia , Microcefalia/virologia , Gravidez , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/virologia
4.
PLoS Negl Trop Dis ; 15(3): e0009259, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33705409

RESUMO

Dengue, Zika and chikungunya are diseases of global health significance caused by arboviruses and transmitted by the mosquito Aedes aegypti, which is of worldwide circulation. The arrival of the Zika and chikungunya viruses to South America increased the complexity of transmission and morbidity caused by these viruses co-circulating in the same vector mosquito species. Here we present an integrated analysis of the reported arbovirus cases between 2007 and 2017 and local climate and socio-economic profiles of three distinct Colombian municipalities (Bello, Cúcuta and Moniquirá). These locations were confirmed as three different ecosystems given their contrasted geographic, climatic and socio-economic profiles. Correlational analyses were conducted with both generalised linear models and generalised additive models for the geographical data. Average temperature, minimum temperature and wind speed were strongly correlated with disease incidence. The transmission of Zika during the 2016 epidemic appeared to decrease circulation of dengue in Cúcuta, an area of sustained high incidence of dengue. Socio-economic factors such as barriers to health and childhood services, inadequate sanitation and poor water supply suggested an unfavourable impact on the transmission of dengue, Zika and chikungunya in all three ecosystems. Socio-demographic influencers were also discussed including the influx of people to Cúcuta, fleeing political and economic instability from neighbouring Venezuela. Aedes aegypti is expanding its range and increasing the global threat of these diseases. It is therefore vital that we learn from the epidemiology of these arboviruses and translate it into an actionable local knowledge base. This is even more acute given the recent historical high of dengue cases in the Americas in 2019, preceding the COVID-19 pandemic, which is itself hampering mosquito control efforts.


Assuntos
Febre de Chikungunya/epidemiologia , Dengue/epidemiologia , Infecção por Zika virus/epidemiologia , Aedes/fisiologia , Aedes/virologia , Animais , Febre de Chikungunya/economia , Febre de Chikungunya/virologia , Vírus Chikungunya/fisiologia , Clima , Colômbia/epidemiologia , Dengue/economia , Dengue/virologia , Vírus da Dengue/fisiologia , Ecossistema , Humanos , Mosquitos Vetores/fisiologia , Mosquitos Vetores/virologia , América do Sul , Temperatura , Zika virus/fisiologia , Infecção por Zika virus/economia , Infecção por Zika virus/virologia
5.
Acta Trop ; 218: 105885, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33713628

RESUMO

Aedes aegypti and Aedes albopictus are mosquito vectors of numerous arboviruses of sanitary importance. Presently in Argentina, neither Ae. aegypti nor Ae. albopictus, have displaced the other species in the places where they coexist, since the introduction of the latter in 1998. In this study, we evaluated whether these species coexist at different scales (ovitrap, microhabitat and habitat) in the city of Eldorado, Misiones province, northeast Argentina. We also analyzed the seasonal variation and climate variables related to the delay in egg hatching of both species. Mosquitoes were collected weekly, from June 2017 to May 2018, using ovitraps placed in urban areas. We conclude that Ae. aegypti and Ae. albopictus coexist in the study area, at the ovitrap, microhabitat and habitat scales. Furthermore, no pronounced pattern of delayed hatching has been observed for either species; however, eggs of Ae. albopictus laid during colder weeks and less rainfall needed a greater number of immersions to hatch, while for Ae. aegypti those laid during weeks with low rainfall and high temperatures showed the longest delay in hatching response.


Assuntos
Aedes/fisiologia , Aedes/virologia , Mosquitos Vetores/fisiologia , Mosquitos Vetores/virologia , Ovulação , Clima Tropical , Animais , Arbovirus/fisiologia , Argentina , Cidades , Ecossistema , Estações do Ano
6.
Biomed Res Int ; 2021: 6649038, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763480

RESUMO

Background: Genetic modification offers opportunities to introduce artificially created molecular defence mechanisms to vector mosquitoes to counter diseases causing pathogens such as the dengue virus, malaria parasite, and Zika virus. RNA interference is such a molecular defence mechanism that could be used for this purpose to block the transmission of pathogens among human and animal populations. In our previous study, we engineered a dengue-resistant transgenic Ae. aegypti using RNAi to turn off the expression of dengue virus serotype genomes to reduce virus transmission, requiring assessment of the fitness of this mosquito with respect to its wild counterpart in the laboratory and semifield conditions. Method: Developmental and reproductive fitness parameters of TM and WM have assessed under the Arthropod Containment Level 2 conditions, and the antibiotic treatment assays were conducted using co-trimoxazole, amoxicillin, and doxycycline to assess the developmental and reproductive fitness parameters. Results: A significant reduction of developmental and reproductive fitness parameters was observed in transgenic mosquito compared to wild mosquitoes. However, it was seen in laboratory-scale studies that the fitness of this mosquito has improved significantly in the presence of antibiotics such as co-trimoxazole, amoxicillin, and doxycycline in their feed. Conclusion: Our data indicate that the transgenic mosquito produced had a reduction of the fitness parameters and it may lead to a subsequent reduction of transgenic vector density over the generations in field applications. However, antibiotics of co-trimoxazole, amoxicillin, and doxycycline have shown the improvement of fitness parameters indicating the usefulness in field release of transgenic mosquitoes.


Assuntos
Animais Geneticamente Modificados , Antibacterianos/farmacologia , Vírus da Dengue/fisiologia , Aptidão Genética , Mosquitos Vetores , Replicação Viral , Aedes/genética , Aedes/virologia , Animais , Dengue/genética , Dengue/prevenção & controle , Dengue/transmissão , Mosquitos Vetores/genética , Mosquitos Vetores/virologia , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
7.
J Med Entomol ; 58(2): 983-989, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33710313

RESUMO

Madagascar is a hotspot of biodiversity, but poverty and population growth provoke a high risk of conflict between food security and biodiversity conservation in this tropical country. Numerous vector-borne diseases, including viral infections, affect public health in Madagascar and a continuous expansion of anthropogenically used areas intensifies contact on the human-wildlife interface. However, data on human and animal pathogens in potential insect vectors is limited. Therefore, we conducted a parasitological and virological survey of 785 adult female mosquitoes between March and May 2016 at the Ankarafantsika National Park in northwestern Madagascar. Screening included Alpha-, Phlebo-, and Flaviviridae and the recently described filarial nematode species, Lemurfilaria lemuris. The predominant mosquito genus was Culex (91%), followed by Mansonia (4.1%), Anopheles (3.4%), and Aedes (0.9%). Viral screening revealed no arboviruses, but an insect-specific flavivirus in two Culex sitiens pools. No pools screened positive for the lemur-specific filarial nematode L. lemuris.


Assuntos
Flavivirus/isolamento & purificação , Mosquitos Vetores , Nematoides/isolamento & purificação , Aedes/parasitologia , Aedes/virologia , Animais , Anopheles/parasitologia , Anopheles/virologia , Biodiversidade , Culex/parasitologia , Culex/virologia , Reservatórios de Doenças , Filariose/transmissão , Lemur , Madagáscar , Mosquitos Vetores/parasitologia , Mosquitos Vetores/virologia , Viroses/transmissão
8.
Nat Commun ; 12(1): 1810, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33753725

RESUMO

For most pathogens, transmission is driven by interactions between the behaviours of infectious individuals, the behaviours of the wider population, the local environment, and immunity. Phylogeographic approaches are currently unable to disentangle the relative effects of these competing factors. We develop a spatiotemporally structured phylogenetic framework that addresses these limitations by considering individual transmission events, reconstructed across spatial scales. We apply it to geocoded dengue virus sequences from Thailand (N = 726 over 18 years). We find infected individuals spend 96% of their time in their home community compared to 76% for the susceptible population (mainly children) and 42% for adults. Dynamic pockets of local immunity make transmission more likely in places with high heterotypic immunity and less likely where high homotypic immunity exists. Age-dependent mixing of individuals and vector distributions are not important in determining spread. This approach provides previously unknown insights into one of the most complex disease systems known and will be applicable to other pathogens.


Assuntos
Algoritmos , Vírus da Dengue/genética , Dengue/transmissão , Modelos Teóricos , Adulto , Aedes/virologia , Animais , Criança , Dengue/epidemiologia , Dengue/virologia , Vírus da Dengue/classificação , Vírus da Dengue/fisiologia , Genoma Viral/genética , Interações Hospedeiro-Patógeno , Humanos , Mosquitos Vetores/virologia , Filogenia , Filogeografia/métodos , Filogeografia/estatística & dados numéricos , Dinâmica Populacional , Tailândia/epidemiologia
9.
PLoS Negl Trop Dis ; 15(2): e0008524, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33591970

RESUMO

BACKGROUND: The mosquito Aedes aegypti is a major vector for the arthropod-borne viruses (arboviruses) chikungunya, dengue, yellow fever and Zika viruses. Vector immune responses pose a major barrier to arboviral transmission, and transgenic insects with altered immunity have been proposed as tools for reducing the global public health impact of arboviral diseases. However, a better understanding of virus-immune interactions is needed to progress the development of such transgenic insects. Although the NF-κB-regulated Toll and 'immunodeficiency' (Imd) pathways are increasingly thought to be antiviral, relevant pattern recognition receptors (PRRs) and pathogen-associated molecular patterns (PAMPs) remain poorly characterised in A. aegypti. METHODOLOGY/PRINCIPLE FINDINGS: We developed novel RT-qPCR and luciferase reporter assays to measure induction of the Toll and Imd pathways in the commonly used A. aegypti-derived Aag2 cell line. We thus determined that the Toll pathway is not inducible by exogenous stimulation with bacterial, viral or fungal stimuli in Aag2 cells under our experimental conditions. We used our Imd pathway-specific assays to demonstrate that the viral dsRNA mimic poly(I:C) is sensed by the Imd pathway, likely through intracellular and extracellular PRRs. The Imd pathway was also induced during infection with the model insect-specific virus cricket paralysis virus (CrPV). CONCLUSIONS/SIGNIFICANCE: Our demonstration that a general PAMP shared by many arboviruses is sensed by the Imd pathway paves the way for future studies to determine how viral RNA is sensed by mosquito PRRs at a molecular level. Our data also suggest that studies measuring inducible immune pathway activation through antimicrobial peptide (AMP) expression in Aag2 cells should be interpreted cautiously given that the Toll pathway is not responsive under all experimental conditions. With no antiviral therapies and few effective vaccines available to treat arboviral diseases, our findings provide new insights relevant to the development of transgenic mosquitoes as a means of reducing arbovirus transmission.


Assuntos
Aedes/virologia , Alphavirus/fisiologia , NF-kappa B/imunologia , Padrões Moleculares Associados a Patógenos/imunologia , Replicação Viral , Animais , Linhagem Celular , Inativação Gênica , Mosquitos Vetores , RNA Viral/análise , Receptores de Reconhecimento de Padrão , Transdução de Sinais
10.
Nat Commun ; 12(1): 916, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568638

RESUMO

The global emergence of Zika virus (ZIKV) revealed the unprecedented ability for a mosquito-borne virus to cause congenital birth defects. A puzzling aspect of ZIKV emergence is that all human outbreaks and birth defects to date have been exclusively associated with the Asian ZIKV lineage, despite a growing body of laboratory evidence pointing towards higher transmissibility and pathogenicity of the African ZIKV lineage. Whether this apparent paradox reflects the use of relatively old African ZIKV strains in most laboratory studies is unclear. Here, we experimentally compare seven low-passage ZIKV strains representing the recently circulating viral genetic diversity. We find that recent African ZIKV strains display higher transmissibility in mosquitoes and higher lethality in both adult and fetal mice than their Asian counterparts. We emphasize the high epidemic potential of African ZIKV strains and suggest that they could more easily go unnoticed by public health surveillance systems than Asian strains due to their propensity to cause fetal loss rather than birth defects.


Assuntos
Infecção por Zika virus/mortalidade , Infecção por Zika virus/virologia , Zika virus/fisiologia , Zika virus/patogenicidade , Aedes/fisiologia , Aedes/virologia , África , Animais , Ásia , Feminino , Humanos , Masculino , Camundongos , Filogenia , Virulência , Zika virus/classificação , Zika virus/genética , Infecção por Zika virus/transmissão
11.
Mem Inst Oswaldo Cruz ; 115: e200313, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33533870

RESUMO

BACKGROUND: Aedes aegypti is the sole vector of urban arboviruses in French Guiana. Overtime, the species has been responsible for the transmission of viruses during yellow fever, dengue, chikungunya and Zika outbreaks. Decades of vector control have produced resistant populations to deltamethrin, the sole molecule available to control adult mosquitoes in this French Territory. OBJECTIVES: Our surveillance aimed to provide public health authorities with data on insecticide resistance in Ae. aegypti populations and other species of interest in French Guiana. Monitoring resistance to the insecticide used for vector control and to other molecule is a key component to develop an insecticide resistance management plan. METHODS: In 2009, we started to monitor resistance phenotypes to deltamethrin and target-site mechanisms in Ae. aegypti populations across the territory using the WHO impregnated paper test and allelic discrimination assay. FINDINGS: Eight years surveillance revealed well-installed resistance and the dramatic increase of alleles on the sodium voltage-gated gene, known to confer resistance to pyrethroids (PY). In addition, we observed that populations were resistant to malathion (organophosphorous, OP) and alpha-cypermethrin (PY). Some resistance was also detected to molecules from the carbamate family. Finally, those populations somehow recovered susceptibility against fenitrothion (OP). In addition, other species distributed in urban areas revealed to be also resistant to pyrethroids. CONCLUSION: The resistance level can jeopardize the efficiency of chemical adult control in absence of other alternatives and conducts to strongly rely on larval control measures to reduce mosquito burden. Vector control strategies need to evolve to maintain or regain efficacy during epidemics.


Assuntos
Aedes/efeitos dos fármacos , Insetos Vetores/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Mosquitos Vetores/efeitos dos fármacos , Piretrinas/farmacologia , Aedes/genética , Aedes/virologia , Animais , Guiana Francesa , Insetos Vetores/efeitos dos fármacos , Controle de Mosquitos/métodos , Mosquitos Vetores/virologia , Análise Espaço-Temporal
12.
Nursing (Säo Paulo) ; 24(273): 5229-5242, fev.2021.
Artigo em Português | LILACS, BDENF - Enfermagem | ID: biblio-1148490

RESUMO

Objetivo: descrever incidência de dengue em Santos/SP e relacionar coeficiente de incidência (CI) de dengue com indicadores socioeconômicos e entomológicos de 2012-2016. Método: estudo epidemiológico, descritivo, ecológico dos casos confirmados de dengue, residentes em Santos, de 2012-2016, do Sistema de Informação de Agravos de Notificação-Online; foram obtidos seis indicadores socioeconômicos da base de setores censitários do Instituto Brasileiro de Geografia e Estatística-2010; o sétimo do Índice Paulista de Vulnerabilidade Social-2010 e os indicadores entomológicos da Secretaria de Saúde; foi aplicada Correlação bivariada de Spearman (SPSS-Statistics®). Aprovado pelo Comitê de Ética em Pesquisa-CAAE nº79776017.1.0000.5479. Resultados: de 2012-2016 ocorreram 16.451 casos, com CI de 117,4 (2012) a 2.122,8 (2013) casos/100.000 habitantes, maior no sexo feminino e de 15-29 anos; os fatores socioeconômicos foram mais significativos entre 2015-2016; o Índice de Densidade de fêmeas Aedes aegypti apresentou maior correlação positiva. Conclusão: descreveu-se perfil epidemiológico/entomológico da dengue, apoiando gestores nas ações locais de controle.(AU)


Objectives: describe incidence of dengue in Santos/SP and relate dengue incidence coefficient (IC) with socioeconomic and entomological indicators from 2012-2016. Methods: epidemiological, descriptive, ecological study of confirmed cases of dengue, resident in Santos, from 2012-2016, of the Online-Notifiable Diseases Information System; six socioeconomic indicators were obtained from census sectors base of Brazilian Institute of Geography and Statistics-2010; the seventh from the São Paulo Index of Social Vulnerability-2010 and the entomological indicators from the Health Department; Spearman's Bivariate Correlation (SPSS-Statistics®) was applied. Approved by the Research Ethics Committee-CAAE nº79776017.1.0000.5479. Results: from 2012-2016 there were 16.451 cases, with IC from 117,4 (2012) to 2.122,8 (2013) cases/100.000 inhabitants, higher in females and between 15-29 years old; socioeconomic factors were more significant between 2015-2016; the Density Index of Aedes aegypti females showed a greater positive correlation. Conclusion: epidemiological/entomological profile of dengue was described, supporting managers in local control actions.(AU)


Objetivos: describir incidencia del dengue en Santos/SP y relacionar coeficiente de incidencia (CI) del dengue con indicadores socioeconómicos y entomológicos para 2012-2016. Métodos: estudio epidemiológico, descriptivo, ecológico de casos confirmados de dengue, residentes en Santos, desde 2012-2016, del Sistema de Información de Enfermedades de Notificación-Online; obtuvieron-se seis indicadores socioeconómicos desde base de sectores censales del Instituto Brasileño de Geografía y Estadística-2010, el séptimo del Índice de Vulnerabilidad Social de São Paulo-2010 y los indicadores entomológicos del Departamento de Salud. Aplicó-se Correlación Bivariada de Spearman (SPSS-Statistics®). Aprobado por el Comité de Ética en Investigación-CAAE nº79776017.1.0000.5479. Resultados: desde 2012-2016 hubo 16.451 casos, con CI de 117,4 (2012) a 2.122,8 (2013) casos/100.000 habitantes, mayor en mujeres y de 15-29 años; los factores socioeconómicos fueron más significativos entre 2015-2016; el Índice de Densidad de hembras Aedes aegypti mostró mayor correlación positiva. Conclusión: describió-se perfil epidemiológico/entomológico del dengue, apoyando a los gerentes en acciones de control local.(AU)


Assuntos
Humanos , Animais , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Aedes/virologia , Dengue/epidemiologia , Mosquitos Vetores/virologia , Fatores Socioeconômicos , Fatores Sexuais , Incidência , Fatores Etários , Estudos Ecológicos , Índice de Vulnerabilidade Social
13.
Acta Trop ; 216: 105829, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33465350

RESUMO

The aim of this study is to investigate the feasibility and outcomes of using Gravid Oviposition Sticky (GOS) trap and dengue NS1 antigen tests for indoor and outdoor dengue/Aedes surveillance in the field. A one-year community-based study was carried out at Sungai Buloh Hospital Quarters, Selangor, Malaysia. GOS traps were first placed outdoors in three apartment blocks (Anggerik, Bunga Raya and Mawar). Beginning 29th week of the study, indoor traps were set in two apartment units on every floor in Anggerik. All female Aedes mosquitoes caught were tested for the presence of dengue NS1 antigen. Dengue seroprevalence and knowledge, attitude and practices on dengue prevention of the community and their reception to the surveillance approach were also assessed. Dengue-positive mosquitoes were detected at least 1 week before a dengue onset. More mosquitoes were caught indoors than outdoors in block Anggerik, but the total number of mosquitoes caught in all 3 blocks were similar. There was a significant difference in distribution of Ae. aegypti and Ae. albopictus between the 3 blocks. 66.1% and 3.4% of the community were positive for dengue IgG and IgM, respectively. Most respondents think that this surveillance method is Good (89%) and support its use nationwide. Dengue case ratio in the study apartment blocks decreased from year 2018 to 2019. This study demonstrated the practicality of performing proactive dengue/Aedes surveillance inside apartment units using the GOS traps. This surveillance method can be performed with immediate result output in the field.


Assuntos
Aedes/virologia , Dengue/prevenção & controle , Controle de Mosquitos/métodos , Oviposição , Proteínas não Estruturais Virais/análise , Animais , Dengue/epidemiologia , Dengue/transmissão , Entomologia , Feminino , Humanos , Estudos Soroepidemiológicos
14.
PLoS Negl Trop Dis ; 15(1): e0008972, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33395435

RESUMO

Arbovirus infection in Aedes aegypti has historically been quantified from a sample of the adult population by pooling collected mosquitoes to increase detectability. However, there is a significant knowledge gap about the magnitude of natural arbovirus infection within areas of active transmission, as well as the sensitivity of detection of such an approach. We used indoor Ae. aegypti sequential sampling with Prokopack aspirators to collect all mosquitoes inside 200 houses with suspected active ABV transmission from the city of Mérida, Mexico, and tested all collected specimens by RT-PCR to quantify: a) the absolute arbovirus infection rate in individually tested Ae. aegypti females; b) the sensitivity of using Prokopack aspirators in detecting ABV-infected mosquitoes; and c) the sensitivity of entomological inoculation rate (EIR) and vectorial capacity (VC), two measures ABV transmission potential, to different estimates of indoor Ae. aegypti abundance. The total number of Ae. aegypti (total catch, the sum of all Ae. aegypti across all collection intervals) as well as the number on the first 10-min of collection (sample, equivalent to a routine adult aspiration session) were calculated. We individually tested by RT-PCR 2,161 Aedes aegypti females and found that 7.7% of them were positive to any ABV. Most infections were CHIKV (77.7%), followed by DENV (11.4%) and ZIKV (9.0%). The distribution of infected Aedes aegypti was overdispersed; 33% houses contributed 81% of the infected mosquitoes. A significant association between ABV infection and Ae. aegypti total catch indoors was found (binomial GLMM, Odds Ratio > 1). A 10-min indoor Prokopack collection led to a low sensitivity of detecting ABV infection (16.3% for detecting infected mosquitoes and 23.4% for detecting infected houses). When averaged across all infested houses, mean EIR ranged between 0.04 and 0.06 infective bites per person per day, and mean VC was 0.6 infectious vectors generated from a population feeding on a single infected host per house/day. Both measures were significantly and positively associated with Ae. aegypti total catch indoors. Our findings provide evidence that the accurate estimation and quantification of arbovirus infection rate and transmission risk is a function of the sampling effort, the local abundance of Aedes aegypti and the intensity of arbovirus circulation.


Assuntos
Aedes/virologia , Infecções por Arbovirus/epidemiologia , Mosquitos Vetores/virologia , Animais , Infecções por Arbovirus/diagnóstico , Infecções por Arbovirus/transmissão , Feminino , Masculino , Densidade Demográfica
15.
PLoS Negl Trop Dis ; 15(1): e0008351, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33481791

RESUMO

The Asian tiger mosquito, Aedes albopictus (Ae. albopictus), is an important vector that transmits arboviruses such as dengue (DENV), Zika (ZIKV) and Chikungunya virus (CHIKV). Long noncoding RNAs (lncRNAs) are known to regulate various biological processes. Knowledge on Ae. albopictus lncRNAs and their functional role in virus-host interactions are still limited. Here, we identified and characterized the lncRNAs in the genome of an arbovirus vector, Ae. albopictus, and evaluated their potential involvement in DENV and ZIKV infection. We used 148 public datasets, and identified a total of 10, 867 novel lncRNA transcripts, of which 5,809, 4,139, and 919 were intergenic, intronic and antisense respectively. The Ae. albopictus lncRNAs shared many characteristics with other species such as short length, low GC content, and low sequence conservation. RNA-sequencing of Ae. albopictus cells infected with DENV and ZIKV showed that the expression of lncRNAs was altered upon virus infection. Target prediction analysis revealed that Ae. albopictus lncRNAs may regulate the expression of genes involved in immunity and other metabolic and cellular processes. To verify the role of lncRNAs in virus infection, we generated mutations in lncRNA loci using CRISPR-Cas9, and discovered that two lncRNA loci mutations, namely XLOC_029733 (novel lncRNA transcript id: lncRNA_27639.2) and LOC115270134 (known lncRNA transcript id: XR_003899061.1) resulted in enhancement of DENV and ZIKV replication. The results presented here provide an important foundation for future studies of lncRNAs and their relationship with virus infection in Ae. albopictus.


Assuntos
Aedes/genética , Aedes/virologia , Vírus da Dengue/fisiologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Zika virus/fisiologia , Aedes/metabolismo , Animais , Sistemas CRISPR-Cas , Linhagem Celular , Dengue/virologia , Vírus da Dengue/genética , Regulação da Expressão Gênica , Genoma , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Mosquitos Vetores/genética , Mosquitos Vetores/virologia , Transcriptoma , Zika virus/genética , Infecção por Zika virus/virologia
16.
Nat Commun ; 12(1): 595, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33500409

RESUMO

Zika virus (ZIKV) emerged from obscurity in 2013 to spread from Asia to the South Pacific and the Americas, where millions of people were infected, accompanied by severe disease including microcephaly following congenital infections. Phylogenetic studies have shown that ZIKV evolved in Africa and later spread to Asia, and that the Asian lineage is responsible for the recent epidemics in the South Pacific and Americas. However, the reasons for the sudden emergence of ZIKV remain enigmatic. Here we report evolutionary analyses that revealed four mutations, which occurred just before ZIKV introduction to the Americas, represent direct reversions of previous mutations that accompanied earlier spread from Africa to Asia and early circulation there. Our experimental infections of Aedes aegypti mosquitoes, human cells, and mice using ZIKV strains with and without these mutations demonstrate that the original mutations reduced fitness for urban, human-amplifed transmission, while the reversions restored fitness, increasing epidemic risk. These findings include characterization of three transmission-adaptive ZIKV mutations, and demonstration that these and one identified previously restored fitness for epidemic transmission soon before introduction into the Americas. The initial mutations may have followed founder effects and/or drift when the virus was introduced decades ago into Asia.


Assuntos
Epidemias , Evolução Molecular , Aptidão Genética , Infecção por Zika virus/epidemiologia , Zika virus/genética , Aedes/virologia , África/epidemiologia , América/epidemiologia , Substituição de Aminoácidos , Animais , Ásia/epidemiologia , Linhagem Celular , Modelos Animais de Doenças , Feminino , Fibroblastos , Humanos , Queratinócitos , Camundongos , Mutação , Filogenia , Cultura Primária de Células , Saúde da População Urbana/estatística & dados numéricos , Zika virus/patogenicidade , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
17.
Parasit Vectors ; 14(1): 76, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482887

RESUMO

BACKGROUND: On 11 March 2020, the World Health Organisation (WHO) declared the coronavirus disease 2019 (COVID-19) outbreak to be a pandemic. As the mosquito season progressed, the understandable concern that mosquitoes could transmit the virus began to increase among the general public and public health organisations. We have investigated the vector competence of Culex pipiens and Aedes albopictus, the two most common species of vector mosquitoes in Europe, for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Due to the very unusual feeding behaviour of Ae. albopictus, we also evaluated the role of this mosquito in a potential mechanical transmission of the virus. METHODS: For the vector competence study, mosquitoes were allowed to take several infectious blood meals. The mosquitoes were then collected and analysed at 0, 3, 7 and 10 days post-feeding. For the mechanical transmission test, Ae. albopictus females were allowed to feed for a short time on a feeder containing infectious blood and then on a feeder containing virus-free blood. Both mosquitoes and blood were tested for viral presence. RESULTS: Culex pipiens and Ae. albopictus were found not be competent vectors for SARS-CoV-2, and Ae. albopictus was unable to mechanically transmit the virus. CONCLUSIONS: This is the first study to show that the most common species of vector mosquitoes in Europe do not transmit SARS-CoV-2 and that Ae. albopictus is unable to mechanically transmit the virus from a positive host to a healthy host through host-feeding.


Assuntos
Aedes/virologia , Culex/virologia , Mosquitos Vetores/virologia , /fisiologia , Animais , Sangue/virologia , Europa (Continente) , Feminino , RNA Viral/análise , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Ovinos/sangue
18.
Nat Commun ; 12(1): 151, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420058

RESUMO

Mosquito-borne viruses threaten the Caribbean due to the region's tropical climate and seasonal reception of international tourists. Outbreaks of chikungunya and Zika have demonstrated the rapidity with which these viruses can spread. Concurrently, dengue fever cases have climbed over the past decade. Sustainable disease control measures are urgently needed to quell virus transmission and prevent future outbreaks. Here, to improve upon current control methods, we analyze temporal and spatial patterns of chikungunya, Zika, and dengue outbreaks reported in the Dominican Republic between 2012 and 2018. The viruses that cause these outbreaks are transmitted by Aedes mosquitoes, which are sensitive to seasonal climatological variability. We evaluate whether climate and the spatio-temporal dynamics of dengue outbreaks could explain patterns of emerging disease outbreaks. We find that emerging disease outbreaks were robust to the climatological and spatio-temporal constraints defining seasonal dengue outbreak dynamics, indicating that constant surveillance is required to prevent future health crises.


Assuntos
Febre de Chikungunya/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Dengue/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Doenças Endêmicas/estatística & dados numéricos , Infecção por Zika virus/epidemiologia , Adolescente , Aedes/virologia , Animais , Febre de Chikungunya/prevenção & controle , Febre de Chikungunya/transmissão , Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Criança , Pré-Escolar , Doenças Transmissíveis Emergentes/prevenção & controle , Doenças Transmissíveis Emergentes/transmissão , Doenças Transmissíveis Emergentes/virologia , Dengue/prevenção & controle , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/isolamento & purificação , Surtos de Doenças/prevenção & controle , República Dominicana/epidemiologia , Doenças Endêmicas/prevenção & controle , Monitoramento Epidemiológico , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Controle de Mosquitos , Mosquitos Vetores/virologia , Análise Espaço-Temporal , Adulto Jovem , Zika virus/isolamento & purificação , Infecção por Zika virus/prevenção & controle , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
19.
Viruses ; 13(1)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466915

RESUMO

Mosquito-borne arthropod-borne viruses (arboviruses) such as the dengue virus (DENV), Zika virus (ZIKV), and chikungunya virus (CHIKV) are important human pathogens that are responsible for significant global morbidity and mortality. The recent emergence and re-emergence of mosquito-borne viral diseases (MBVDs) highlight the urgent need for safe and effective vaccines, therapeutics, and vector-control approaches to prevent MBVD outbreaks. In nature, arboviruses circulate between vertebrate hosts and arthropod vectors; therefore, disrupting the virus lifecycle in mosquitoes is a major approach for combating MBVDs. Several strategies were proposed to render mosquitoes that are refractory to arboviral infection, for example, those involving the generation of genetically modified mosquitoes or infection with the symbiotic bacterium Wolbachia. Due to the recent development of high-throughput screening methods, an increasing number of drugs with inhibitory effects on mosquito-borne arboviruses in mammalian cells were identified. These antivirals are useful resources that can impede the circulation of arboviruses between arthropods and humans by either rendering viruses more vulnerable in humans or suppressing viral infection by reducing the expression of host factors in mosquitoes. In this review, we summarize recent advances in small-molecule antiarboviral drugs in mammalian and mosquito cells, and discuss how to use these antivirals to block the transmission of MBVDs.


Assuntos
Aedes/virologia , Antivirais/farmacologia , Infecções por Arbovirus/transmissão , Infecções por Arbovirus/virologia , Arbovirus/efeitos dos fármacos , Mosquitos Vetores/virologia , Aedes/efeitos dos fármacos , Animais , Antivirais/química , Antivirais/uso terapêutico , Infecções por Arbovirus/tratamento farmacológico , Arbovirus/classificação , Células Cultivadas , Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos , Humanos , Controle de Mosquitos/métodos , Doenças Transmitidas por Vetores/tratamento farmacológico , Doenças Transmitidas por Vetores/transmissão , Doenças Transmitidas por Vetores/virologia , Replicação Viral/efeitos dos fármacos
20.
Parasit Vectors ; 14(1): 12, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407824

RESUMO

BACKGROUND: Aedes albopictus is an indigenous primary vector for dengue and Zika viruses in China. Compared with its insecticide resistance, biology and vector competence, little is known about its genetic variation, which corresponds to environmental variations. Thus, the present study examines how Ae. albopictus varies among different climatic regions in China and deciphers its potential dispersal patterns. METHODS: The genetic variation and population structure of 17 Ae. albopictus populations collected from three climatic regions of China were investigated with 11 microsatellite loci and the mitochondrial coxI gene. RESULTS: Of 44 isolated microsatellite markers, 11 pairs were chosen for genotyping analysis and had an average PIC value of 0.713, representing high polymorphism. The number of alleles was high in each population, with the ne value increasing from the temperate region (3.876) to the tropical region (4.144). Twenty-five coxI haplotypes were detected, and the highest diversity was observed in the tropical region. The mean Ho value (ca. 0.557) of all the regions was significantly lower than the mean He value (ca. 0.684), with nearly all populations significantly departing from HWE and displaying significant population expansion (p value < 0.05). Two genetically isolated groups and three haplotype clades were evaluated via STRUCTURE and haplotype phylogenetic analyses, and the tropical populations were significantly isolated from those in the other regions. Most genetic variation in Ae. albopictus was detected within populations and individuals at 31.40 and 63.04%, respectively, via the AMOVA test, and a relatively significant positive correlation was observed among only the temperate populations via IBD analysis (R2 = 0.6614, p = 0.048). Recent dispersions were observed among different Ae. albopictus populations, and four major migration trends with high gene flow (Nm > 0.4) were reconstructed between the tropical region and the other two regions. Environmental factors, especially temperature and rainfall, may be the leading causes of genetic diversity in different climatic regions. CONCLUSIONS: Continuous dispersion contributes to the genetic communication of Ae. albopictus populations across different climatic regions, and environmental factors, especially temperature and rainfall, may be the leading causes of genetic variation.


Assuntos
Aedes/genética , Distribuição Animal , Genética Populacional , Aedes/virologia , Animais , China/epidemiologia , Clima , Dengue/transmissão , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes de Insetos , Variação Genética , Repetições de Microssatélites/genética , Mosquitos Vetores/genética , Mosquitos Vetores/virologia , Filogenia , Polimorfismo Genético , Infecção por Zika virus/transmissão
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