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1.
Pestic Biochem Physiol ; 174: 104823, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33838716

RESUMEN

Conventional and volatile pyrethroids are widely used to control the vectors of dengue arboviral diseases, Aedes albopictus in China. The development of resistance to conventional pyrethroids has become an increasing problem, potentially affecting the use of volatile pyrethroid. The Ae. albopictus dimefluthrin-resistant (R) strain by selecting the field population with dimefluthrin were investigated the multiple and cross-resistance levels between conventional and volatile pyrethroids and analyzed both target-site and metabolic resistant mechanisms to dimefluthrin compared with three volatile pyrethroids metofluthrin, meperfluthrin and esbiothrin and type II pyrethroid deltamethrin. The R strain displayed moderate to low resistance to selected pyrethroids (dimefluthrin, metofluthrin, meperfluthrin, esbiothrin and deltamethrin) associated with metabolic enzymes, but less distinctly to selected pyrethroids (dimefluthrin and metofluthrin) associated with a high frequency of sodium channel gene mutation (F1534S). Profiles of the multiple and cross-resistance of the R strain to other three volatile pyrethroids and type II pyrethroid deltamethrin were detected. Both synergistic and enzyme activity studies indicated that multifunctional oxidase (MFO) played an important role in this resistance.


Asunto(s)
Aedes , Insecticidas , Piretrinas , Aedes/genética , Animales , China , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Mosquitos Vectores , Piretrinas/farmacología
2.
Arch. argent. pediatr ; 119(2): 131-138, abril 2021. ilus
Artículo en Español | LILACS, BINACIS | ID: biblio-1152134

RESUMEN

A 11 años del primer brote de dengue en Buenos Aires, el 20 de marzo de 2020, mientras se iniciaba la cuarentena obligatoria por COVID-19, dengue pasó a ser la causa más común de consulta por fiebre. La nueva ola de casos de dengue ya se encontraba entre las predicciones de la Organización Panamericana de la Salud en función del aumento en la región de las Américas que se venía presentando desde el año anterior. La llegada del SARS-CoV-2 a principios de marzo, sumada al brote de dengue que ya estaba en curso, resultó en un nuevo desafío para el sistema de salud, mientras comenzaba un paradigma con planes de adaptación a la nueva infección pandémica en el país. La superposición de infecciones con potencial epidémico, como dengue, recuerda la importancia de no desatender otras enfermedades endémicas, emergentes y reemergentes a la sombra del nuevo fenómeno epidemiológico


Eleven years after the first dengue outbreak in Buenos Aires, on March 20, 2020, while the mandatory quarantine for COVID-19 began dengue became the most common cause of fever consultation. The new wave of dengue cases was already among the predictions of the Pan American Health Organization based on the increase in the region of the Americas that had been occurring since the previous year. The arrival of SARS-CoV-2 at the beginning of March, added to the dengue outbreak that was already underway, made a new challenge for the health system while a new paradigm was initiated with adaptation plans to the new pandemic infection in the country. The overlapping of infections with epidemic potential such as dengue recalls the importance of not neglecting other endemic, emerging and re-emerging diseases in the shadow of the new epidemiological phenomenon.


Asunto(s)
Humanos , Dengue/epidemiología , Pediatría , Arbovirus , Argentina/epidemiología , Infecciones por Coronavirus , Aedes , Coinfección
3.
PLoS Negl Trop Dis ; 15(3): e0009259, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33705409

RESUMEN

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.


Asunto(s)
Fiebre Chikungunya/epidemiología , Dengue/epidemiología , Infección por el Virus Zika/epidemiología , Aedes/fisiología , Aedes/virología , Animales , Fiebre Chikungunya/economía , Fiebre Chikungunya/virología , Virus Chikungunya/fisiología , Clima , Colombia/epidemiología , Dengue/economía , Dengue/virología , Virus del Dengue/fisiología , Ecosistema , Humanos , Mosquitos Vectores/fisiología , Mosquitos Vectores/virología , América del Sur , Temperatura , Virus Zika/fisiología , Infección por el Virus Zika/economía , Infección por el Virus Zika/virología
4.
Nat Microbiol ; 6(4): 467-478, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33727702

RESUMEN

Activation of the RIG-I-like receptors, retinoic-acid inducible gene I (RIG-I) and melanoma differentiation-associated protein 5 (MDA5), establishes an antiviral state by upregulating interferon (IFN)-stimulated genes (ISGs). Among these is ISG15, the mechanistic roles of which in innate immunity still remain enigmatic. In the present study, we report that ISG15 conjugation is essential for antiviral IFN responses mediated by the viral RNA sensor MDA5. ISGylation of the caspase activation and recruitment domains of MDA5 promotes its oligomerization and thereby triggers activation of innate immunity against a range of viruses, including coronaviruses, flaviviruses and picornaviruses. The ISG15-dependent activation of MDA5 is antagonized through direct de-ISGylation mediated by the papain-like protease of SARS-CoV-2, a recently emerged coronavirus that has caused the COVID-19 pandemic. Our work demonstrates a crucial role for ISG15 in the MDA5-mediated antiviral response, and also identifies a key immune evasion mechanism of SARS-CoV-2, which may be targeted for the development of new antivirals and vaccines to combat COVID-19.


Asunto(s)
/metabolismo , Citocinas/metabolismo , Inmunidad Innata , Helicasa Inducida por Interferón IFIH1/antagonistas & inhibidores , /inmunología , Ubiquitinas/metabolismo , Aedes , Animales , Chlorocebus aethiops , Cricetinae , Células HEK293 , Humanos , Helicasa Inducida por Interferón IFIH1/metabolismo , Leucocitos Mononucleares , Ratones , Células Vero
5.
Rev Soc Bras Med Trop ; 54: e05762020, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33656151

RESUMEN

INTRODUCTION: Aedes aegypti is the main vector of dengue and yellow fever. Recently, the use of plant-sourced larvicides has gained momentum. METHODS: The hydroethanolic extracts and fractions ofOcotea nutansleaves and stems were bioassayed to determine the larvicidal efficacy of these samples. RESULTS: S-HEX (hexane fraction from the crude stem extract) demonstrated high potential for controlling third-stage larvae, with an LC50 of 14.14 µg.mL-1 (concentration required to inhibit 50% of the treated larvae). CONCLUSIONS: Extracts from O. nutans were effective against third-stage larvae ofA. aegyptiafter 24 h of exposure.


Asunto(s)
Aedes , Insecticidas , Ocotea , Animales , Insecticidas/farmacología , Larva , Mosquitos Vectores , Extractos Vegetales/farmacología , Hojas de la Planta
6.
Braz J Biol ; 82: e236498, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33787746

RESUMEN

Mormodica charantia (Curcubitaceae) is a plant with great medicinal potential, also used as an alternative of mosquitoes control as demonstrated by previous studies. We evaluated the larvicidal activity of crude extracts of ethyl acetate, methanol and hexane from flowers and fruits of M. charantia against Aedes aegypti (Culicidae). Flowers and fruits were macerated in methanol, ethyl acetate and hexane. Bioassays were performed with application of the extracts at final concentrations of 1 - 200 µg/mL in the middle of the third instar larvae of A. aegypti (L3). The results showed high toxicity to ethyl acetate extracts from flowers and fruits at concentrations of 200 µg/mL and 100 µg/mL, with 97% and 87% of larvae mortality (L3), respectively. Hexane extract demonstrated low toxicity, while methanol extract exhibited 78% larval mortality. The data suggested that the ethyl acetate extracts of flowers and fruits of M. charantia can effectively contribute to larvicidal activity. In addition, purification of M. charantia extracts may lead to a promising larvicidal activity to control the A. aegypti population.


Asunto(s)
Aedes , Insecticidas , Momordica charantia , Animales , Insecticidas/farmacología , Larva , Extractos Vegetales/farmacología , Hojas de la Planta
7.
Nat Commun ; 12(1): 1810, 2021 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-33753725

RESUMEN

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.


Asunto(s)
Algoritmos , Virus del Dengue/genética , Dengue/transmisión , Modelos Teóricos , Adulto , Aedes/virología , Animales , Niño , Dengue/epidemiología , Dengue/virología , Virus del Dengue/clasificación , Virus del Dengue/fisiología , Genoma Viral/genética , Interacciones Huésped-Patógeno , Humanos , Mosquitos Vectores/virología , Filogenia , Filogeografía/métodos , Filogeografía/estadística & datos numéricos , Dinámica Poblacional , Tailandia/epidemiología
8.
Ecotoxicol Environ Saf ; 213: 112013, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33601173

RESUMEN

Mosquito larvicides are an effective tool for reducing numbers of adult females that bite and potentially spread pathogenic organisms. Methionine, an essential amino acid in humans, has been previously demonstrated to be a highly effective larvicide against four (4) mosquito species in three (3) genera, Anopheles, Culex and Aedes. The aim of the present study was to determine the potential impact on non-target aquatic organisms of methionine applied as a mosquito larvicide. DL-methionine concentrations ranging from 0.06% to 1.00% were used; wherein the highest concentration of 1.00% would result in 100% mortality within 48 h in mosquitoes. Acute toxicity assays were conducted in accordance with the US Environmental Protection Agency (US EPA) guidelines for the water flea (Daphnia magna Straus; Cladocera: Daphniidae) and the fathead minnow (Pimephales promelas Rafinesque; Cypriniformes: Cyprinidae). Water fleas and fish were placed directly into the solutions in glass containers and tanks for 48-hours and 96-hours, respectively. When applied within the above-mentioned range of effective mosquito larvicide concentrations, DL-methionine meets US EPA criteria as a "practically non-toxic" pesticide for both species. These results suggest that methionine is a viable alternative to current mosquito larvicide options, which are typically classified as moderately to highly toxic and may be a valuable addition to a mosquito integrated pest management program.


Asunto(s)
Organismos Acuáticos , Metionina/toxicidad , Control de Mosquitos , Aedes , Animales , Anopheles , Culex , Cyprinidae , Daphnia , Femenino , Humanos , Larva
9.
Artículo en Inglés | MEDLINE | ID: mdl-33572650

RESUMEN

Aedes aegypti is a cosmopolitan vector for arboviruses dengue, Zika and chikungunya, disseminated in all Brazilian states. The Eco-Bio-Social (EBS) strategy is vital in Aedes aegypti control as it mobilizes stakeholders (government, professionals, society, and academics) to promote healthy environments. This paper describes the rationale and methods of expanding the EBS strategy for Aedes aegypti control in Fortaleza, Northeast Brazil. A cluster, non-randomized controlled clinical trial was developed to analyze the strategy's effectiveness in vulnerable territories (high incidence of dengue and violent deaths; low HDI; substandard urban infrastructure, high population density, and water scarcity). We selected two intervention and two control groups, resulting in a sample of approximately 16,000 properties. The intervention consisted of environmental management by sealing large elevated water tanks, introduction of beta fish in waterholes, elimination of potential breeding sites, and mobilization and training of schoolchildren, endemic disease workers, health workers, social mobilizers, and community leaders; community surveillance of arboviruses; construction and validation of a booklet for the prevention of arboviruses in pregnant women. We analyzed the costs of arboviruses to government and households, the intervention cost-effectiveness, chikungunya's chronicity, and acceptance, sustainability, and governance of vector control actions. The primary outcome (infestation) was analyzed using the house, container, and Breteau indices. We hope that this study will help us understand how to scale up strategies to fight Aedes aegypti in vulnerable areas.


Asunto(s)
Aedes , Dengue , Infección por el Virus Zika , Virus Zika , Animales , Brasil/epidemiología , Niño , Dengue/epidemiología , Dengue/prevención & control , Femenino , Humanos , Control de Mosquitos , Mosquitos Vectores , Embarazo , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/prevención & control
10.
Nat Commun ; 12(1): 916, 2021 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-33568638

RESUMEN

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.


Asunto(s)
Infección por el Virus Zika/mortalidad , Infección por el Virus Zika/virología , Virus Zika/fisiología , Virus Zika/patogenicidad , Aedes/fisiología , Aedes/virología , África , Animales , Asia , Femenino , Humanos , Masculino , Ratones , Filogenia , Virulencia , Virus Zika/clasificación , Virus Zika/genética , Infección por el Virus Zika/transmisión
11.
Ecol Lett ; 24(4): 698-707, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33554374

RESUMEN

Recurring seasonal changes can lead to the evolution of phenological cues. For example, many arthropods undergo photoperiodic diapause, a programmed developmental arrest induced by short autumnal day length. The selective mechanisms that determine the timing of autumnal diapause initiation have not been empirically identified. We quantified latitudinal clines in genetically determined diapause timing of an invasive mosquito, Aedes albopictus, on two continents. We show that variation in diapause timing within and between continents is explained by a novel application of a growing degree day (GDD) model that delineates a location-specific deadline after which it is not possible to complete an additional full life cycle. GDD models are widely used to predict spring phenology by modelling growth and development as physiological responses to ambient temperatures. Our results show that the energy accumulation dynamics represented by GDD models have also led to the evolution of an anticipatory life-history cue in autumn.


Asunto(s)
Aedes , Especies Introducidas , Aedes/genética , Animales , Clima , Fotoperiodo , Estaciones del Año
12.
Nat Commun ; 12(1): 942, 2021 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-33574256

RESUMEN

The mosquito microbiota impacts the physiology of its host and is essential for normal larval development, thereby influencing transmission of vector-borne pathogens. Germ-free mosquitoes generated with current methods show larval stunting and developmental deficits. Therefore, functional studies of the mosquito microbiota have so far mostly been limited to antibiotic treatments of emerging adults. In this study, we introduce a method to produce germ-free Aedes aegypti mosquitoes. It is based on reversible colonisation with bacteria genetically modified to allow complete decolonisation at any developmental stage. We show that, unlike germ-free mosquitoes previously produced using sterile diets, reversibly colonised mosquitoes show no developmental retardation and reach the same size as control adults. This allows us to uncouple the study of the microbiota in larvae and adults. In adults, we detect no impact of bacterial colonisation on mosquito fecundity or longevity. In larvae, data from our transcriptome analysis and diet supplementation experiments following decolonisation suggest that bacteria support larval development by contributing to folate biosynthesis and by enhancing energy storage. Our study establishes a tool to study the microbiota in insects and deepens our knowledge on the metabolic contribution of bacteria to mosquito development.


Asunto(s)
Interacciones Microbiota-Huesped/fisiología , Microbiota/fisiología , Mosquitos Vectores/microbiología , Aedes/genética , Aedes/crecimiento & desarrollo , Aedes/microbiología , Animales , Bacterias/clasificación , Bacterias/genética , Bacterias/crecimiento & desarrollo , Ácido Fólico , Alimentos Fortificados , Tracto Gastrointestinal/microbiología , Regulación de la Expresión Génica , Vida Libre de Gérmenes , Larva/genética , Larva/crecimiento & desarrollo , Larva/microbiología , Metabolismo de los Lípidos , Mosquitos Vectores/crecimiento & desarrollo , ARN Ribosómico 16S
13.
Mem Inst Oswaldo Cruz ; 115: e200313, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33533870

RESUMEN

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.


Asunto(s)
Aedes/efectos de los fármacos , Insectos Vectores/genética , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Mosquitos Vectores/efectos de los fármacos , Piretrinas/farmacología , Aedes/genética , Aedes/virología , Animales , Guyana Francesa , Insectos Vectores/efectos de los fármacos , Control de Mosquitos/métodos , Mosquitos Vectores/virología , Análisis Espacio-Temporal
14.
Nursing (Säo Paulo) ; 24(273): 5229-5242, fev.2021.
Artículo en Portugués | LILACS, BDENF - Enfermería | ID: biblio-1148490

RESUMEN

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)


Asunto(s)
Humanos , Enfermería en Salud Pública , Perfil de Salud , Incidencia , Aedes/virología , Dengue/epidemiología , Índice de Vulnerabilidad Social , Factores Socioeconómicos , Vulnerabilidad ante Desastres/estadística & datos numéricos , Entomología
15.
Recurso de Internet en Portugués | LIS - Localizador de Información en Salud | ID: lis-48013

RESUMEN

A estação mais quente do ano também é conhecida pela intensa propagação de vírus transmitidos pelo mosquito Aedes aegypti, como dengue, zika e chikungunya


Asunto(s)
Aedes , Dengue , Virus Zika
16.
Pest Manag Sci ; 77(5): 2530-2538, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33470514

RESUMEN

BACKGROUND: Resistant populations of Ae. aegypti have been a major problem in arboviruses epidemic areas, generating a strong demand for novel methods of vector control. In this regard, our group has demonstrated the use of curcumin as an efficient photoactive larvicide to eliminate Ae. aegypti larvae. This work was aimed to evaluate the Ae. aegypti (Rockefeller) development under sublethal conditions, using a curcumin/d-mannitol (DMC) formulation. The photolarvicidal efficacy under semi-field and field conditions (wild populations) was also analyzed, as well as the photobleaching and residual activity of DMC. RESULTS: A delay in development time when larvae were exposed to sublethal concentrations of DMC was observed, followed by significant changes in sex ratio and reduction in longevity. DMC also presented a low residual activity when compared to usual larvicides, and had a substantial photolarvicidal activity against wild populations in field trials, achieving 71.3% mortality after 48 h. CONCLUSIONS: Overall, these findings are of great biological importance for the process of enabling the implementation of DMC as a new product in the control of Ae. aegypti larvae, and contributes to the improvement of new plant-based larvicides. © 2021 Society of Chemical Industry.


Asunto(s)
Aedes , Curcumina , Insecticidas , Animales , Insecticidas/farmacología , Larva , Manitol , Mosquitos Vectores , Razón de Masculinidad
17.
Mil Med ; 186(Suppl 1): 82-90, 2021 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-33499489

RESUMEN

INTRODUCTION: Zika virus (ZIKV) is a mild febrile illness generally transmitted via the bite of infected Aedes species mosquitoes, including Aedes aegypti, with the potential to cause neurological complications. Nearly 200 U.S. military installations are located within areas where Aedes mosquitos are found, putting thousands of personnel at risk for infection with ZIKV. This analysis aims to quantify the benefits of interventions, including vaccination, to decrease the risk of ZIKV on U.S. military installations. METHODS: The authors developed a dynamic transmission model to test the "effectiveness" of vaccination, personal protective measures (PPM), and mosquito control at reducing morbidity within U.S. military populations. ZIKV transmission was modeled as a compartmental susceptible-exposed-infected-recovered model tracking interactions between humans and mosquitos and incorporating seasonality of mosquito populations and the potential for herd immunity. The model included two-dose vaccination as well as symptomatic and asymptomatic infection. The model was calibrated against 2016 public health data in Puerto Rico; sensitivity analyses were performed on model parameters and interventions. RESULTS: The greatest reduction in total modeled ZIKV cases resulted from vaccination combined with mosquito control and PPM. All three interventions at their highest estimated level of efficiency reduced ZIKV cases by 99.9% over the baseline case of low-level adherence to PPM. The addition of vaccination had limited additional benefit over effective vector control and PPM since the significant lag to vaccine-induced protection limited effectiveness of vaccination. CONCLUSIONS: Given the current vaccine, the model predicted that up to 92.8% of Zika cases occurring in deployment settings over a 10-year period could be prevented by adding vaccination to current low-level PPM. Combining vaccination with other interventions can reduce cases further. A location-specific cost-benefit analysis would be a valuable contribution to outbreak control policy as it could evaluate the economic impact of the interventions versus the reduced level of illness and downtime in this setting.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Aedes , Animales , Humanos , Mosquitos Vectores , Puerto Rico , Vacunación , Vacunas Virales , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/prevención & control
18.
J Agric Food Chem ; 69(3): 1091-1106, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33432806

RESUMEN

Furanocoumarins are photoactive compounds derived from secondary plant metabolites. They possess many bioactivities, including antioxidative, anticancer, insecticidal, and bactericidal activities. Here, we designed a new scheme for synthesizing 2-arylfuranocoumarin derivatives by condensation, esterification, bromination, and Wittig reaction. We found that 2-thiophenylfuranocoumarin (Iy) had excellent photosensitive activity. Three Iy concentrations (LC25, LC50, and LC75) were used to treat the fourth instar larvae of Aedes aegypti (A. aegypti). The photoactivated toxicity, sublethal dose, mitochondrial dysfunction, oxidative stress level, intestinal barrier dysfunction, and apoptosis were studied. The results showed that Iy induced reactive oxygen species (ROS) production in midgut cells under ultraviolet light. Ultrastructural analysis demonstrated that mitochondria were damaged, and the activities of related enzymes were inhibited. Ultimately, Iy exposure led to excessive ROS production followed by the inhibition of antioxidant enzymes, including SOD, CAT, GPx, and GR, which diminished ROS elimination and escalated oxidative stress in midgut cells, aggravating the degree of oxidative damage in these cells. Histopathological changes were observed in the midgut, which led to intestinal barrier dysfunction. When the elimination of ROS was blocked and it accumulated in cells, apoptosis-related genes, including AeDronc, AeCaspase7, and AeCaspase8, were induced and activated. In addition, Iy affected the growth and development of A. aegypti at sublethal concentrations, and there was an obvious post-lethal effect. Thus, we found that Iy caused midgut damage and apoptosis in A. aegypti larvae under ultraviolet light, which preliminarily revealed the mode of action of Iy in A. aegypti.


Asunto(s)
Aedes/efectos de los fármacos , Apoptosis/efectos de los fármacos , Furocumarinas/química , Furocumarinas/toxicidad , Insecticidas/síntesis química , Insecticidas/toxicidad , Aedes/fisiología , Animales , Sistema Digestivo/efectos de los fármacos , Sistema Digestivo/metabolismo , Insecticidas/química , Larva/efectos de los fármacos , Larva/fisiología , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo
19.
Nat Commun ; 12(1): 151, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33420058

RESUMEN

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.


Asunto(s)
Fiebre Chikungunya/epidemiología , Enfermedades Transmisibles Emergentes/epidemiología , Dengue/epidemiología , Brotes de Enfermedades/estadística & datos numéricos , Enfermedades Endémicas/estadística & datos numéricos , Infección por el Virus Zika/epidemiología , Adolescente , Aedes/virología , Animales , Fiebre Chikungunya/prevención & control , Fiebre Chikungunya/transmisión , Fiebre Chikungunya/virología , Virus Chikungunya/aislamiento & purificación , Niño , Preescolar , Enfermedades Transmisibles Emergentes/prevención & control , Enfermedades Transmisibles Emergentes/transmisión , Enfermedades Transmisibles Emergentes/virología , Dengue/prevención & control , Dengue/transmisión , Dengue/virología , Virus del Dengue/aislamiento & purificación , Brotes de Enfermedades/prevención & control , República Dominicana/epidemiología , Enfermedades Endémicas/prevención & control , Monitoreo Epidemiológico , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Control de Mosquitos , Mosquitos Vectores/virología , Análisis Espacio-Temporal , Adulto Joven , Virus Zika/aislamiento & purificación , Infección por el Virus Zika/prevención & control , Infección por el Virus Zika/transmisión , Infección por el Virus Zika/virología
20.
Viruses ; 13(1)2021 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-33466915

RESUMEN

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.


Asunto(s)
Aedes/virología , Antivirales/farmacología , Infecciones por Arbovirus/transmisión , Infecciones por Arbovirus/virología , Arbovirus/efectos de los fármacos , Mosquitos Vectores/virología , Aedes/efectos de los fármacos , Animales , Antivirales/química , Antivirales/uso terapéutico , Infecciones por Arbovirus/tratamiento farmacológico , Arbovirus/clasificación , Células Cultivadas , Descubrimiento de Drogas/métodos , Evaluación Preclínica de Medicamentos , Humanos , Control de Mosquitos/métodos , Enfermedades Transmitidas por Vectores/tratamiento farmacológico , Enfermedades Transmitidas por Vectores/transmisión , Enfermedades Transmitidas por Vectores/virología , Replicación Viral/efectos de los fármacos
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