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Por meio do sistema de monitoramento, você acessa os artigos publicados nos principais periódicos nacionais e internacionais. 

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Title: A Sensitive and Selective Label-Free Electrochemical DNA Biosensor for the Detection of Specific Dengue Virus Serotype 3 Sequences
Authors: Oliveira, Natália; Souza, Elaine; Ferreira, Danielly; Zanforlin, Deborah; Bezerra, Wessulla; Borba, Maria Amélia; Arruda, Mariana; Lopes, Kennya; Nascimento, Gustavo; Martins, Danyelly; Cordeiro, Marli; Lima-Filho, José

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by Maria Eugenia Toledo, Veerle Vanlerberghe, Julio Popa Rosales, Mayelin Mirabal, Pedro Cabrera, Viviana Fonseca, Tania Gómez Padrón, Mirtha Pérez Menzies, Domingo Montada, Patrick Van der Stuyft
Background Aedes control interventions are considered the cornerstone of dengue control programmes, but there is scarce evidence on their effect on disease. We set-up a cluster randomized controlled trial in Santiago de Cuba to evaluate the entomological and epidemiological effectiveness of periodical intra- and peri-domiciliary residual insecticide (deltamethrin) treatment (RIT) and long lasting insecticide treated curtains (ITC). Methodology/Principal findings Sixty three clusters (around 250 households each) were randomly allocated to two intervention (RIT and ITC) and one control arm. Routine Aedes control activities (entomological surveillance, source reduction, selective adulticiding, health education) were applied in the whole study area. The outcome measures were clinical dengue case incidence and immature Aedes infestation. Effectiveness of tools was evaluated using a generalized linear regression model with a negative binomial link function.Despite significant reduction in Aedes indices (Rate Ratio (RR) 0.54 (95%CI 0.32–0.89) in the first month after RIT, the effect faded out over time and dengue incidence was not reduced. Overall, in this setting there was no protective effect of RIT or ITC over routine in the 17months intervention period, with for house index RR of 1.16 (95%CI 0.96–1.40) and 1.25 (95%CI 1.03–1.50) and for dengue incidence RR of 1.43 (95%CI 1.08–1.90) and 0.96 (95%CI 0.72–1.28) respectively. The monthly dengue incidence rate (IR) at cluster level was best explained by epidemic periods (Incidence Rate Ratio (IRR) 5.50 (95%CI 4.14–7.31)), the IR in bordering houseblocks (IRR 1.03 (95%CI 1.02–1.04)) and the IR pre-intervention (IRR 1.02 (95%CI 1.00–1.04)). Conclusions Adding RIT to an intensive routine Aedes control programme has a transient effect on the already moderate low entomological infestation levels, while ITC did not have any effect. For both interventions, we didn’t evidence impact on disease incidence. Further studies are needed to evaluate impact in settings with high Aedes infestation and arbovirus case load.

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Title: Vigilância do vírus Chikungunya na atual tríplice epidemia de arbovírus no Brasilinvestigação de casos suspeitos e genotipagem dos vírus circulantes
Authors: Souza, Thiara Manuele Alves de
Abstract: O vírus chikungunya (CHIKV) tem sido responsável por importantes epidemias emergentes e reemergentes de uma doença caracterizada por poliartralgia intensa e incapacitante em diversas regiões tropicais e temperadas do mundo. No Brasil, os primeiros casos autóctones do genótipo Asiático deste vírus foram identificados em Oiapoque (AP) durante 2014 e neste mesmo período, o genótipo Leste-Centro-Sul Africano (ECSA) foi introduzido de forma independente em Feira de Santana (BA). Apesar da importância dos mosquitos Ae. aegypti na transmissão desta arbovirose, o vetor Ae. albopictus tem sido associado como um novo causador da doença devido a uma mutação E1-A226V que favoreceu a transmissão do CHIKV por esta espécie. Atualmente, o país vive uma tríplice epidemia de arbovírus (DENV, ZIKV e CHIKV) tornando o diagnóstico diferencial extremamente difícil para os profissionais de saúde. Desta forma, o presente estudo teve como principais objetivos investigar casos suspeitos de CHIKV e a possível ocorrência de co-infecções entre os três arbovírus circulantes, assim como realizar a genotipagem e caracterização molecular a partir do sequenciamento parcial da região E1 das cepas representativas de CHIKV provenientes de epidemias ocorridas no Amapá (AP) e Feira de Santana (BA) em 2014-2015 e em Campo Grande (MS) e Rio de Janeiro (RJ) durante 2016. No AP, os resultados demonstram que 107/208 (51.44%) dos casos avaliados foram confirmados para CHIKV, sendo 71.02% (76/107) da cidade de Oiapoque, 25.23% (27/107) de Macapá e 3.73% (4/107) de Porto Grande. Destes, foram observadas 24 co-infecções por CHIKV e DENV, 2 por CHIKV e DENV-1 e 2 por CHIKV e DENV-4. Na BA, 24/28 (85.71%) dos casos suspeitos foram confirmados para este vírus e destes, 12 co-infecções por CHIKV e DENV foram encontradas. No MS, 7/134 (5.22%) dos casos apresentaram apenas uma evidência sorológica desta infecção, indicando um quadro epidêmico em crescimento nesta região. Destes, foram observadas 1 co-infecção por CHIKV e DENV, 2 por CHIKV e DENV-1 e 1 por CHIKV, DENV-1 e ZIKV. No RJ, 70/91 (76.92%) dos casos foram confirmados para CHIKV, sendo estes prevalentes na Zona Sul da cidade (32.14%), com destaque para os bairros do Catete, Glória e Laranjeiras. Destes, foram observadas 8 co-infecções por CHIKV e DENV e 17 por CHIKV e ZIKV. Adicionalmente, os dados sugerem a predominância de infecção entre indivíduos do sexo feminino e maiores de 15 anos no AP e no RJ. No AP, o maior número de casos foi destacado para indivíduos entre 16 a 20 anos e 26 a 55 anos e no RJ, a maior frequência de casos confirmados foi para indivíduos entre 26 a 30 anos, seguido de 41 a 45 e 51 a 55 anos. Com relação às manifestações clínicas dos casos de CHIKV do AP, MS e RJ, houve predominância de febre, artralgia, mialgia, prostração, edema, exantema, hiperemia conjuntival, lombalgia, tontura, náusea, dor retro-orbitária e anorexia. Por fim, apesar de não ter sido observada nenhuma alteração de aminoácidos, foi demonstrado que todas as cepas de CHIKV do AP analisadas pertencem ao genótipo Asiático. No RJ, foi demonstrada pela primeira vez a circulação do ECSA nesta região e nenhuma mutação A226V foi observada. Apesar disso, foi revelada uma alteração E1-V156A em duas amostras e pela primeira vez na literatura a mutação E1-K211T em todas as amostras analisadas. Outros estudos serão necessários para esclarecer as consequências destas mudanças no fitness dos mosquitos e no sistema imunológico humano, sendo de fundamental importância o monitoramento dos casos suspeitos de CHIKV e da dispersão dos genótipos circulantes, além da identificação de possíveis mutações que facilitam a transmissão pelos mosquitos vetores, especialmente em regiões onde há um amplo território, alta densidade do vetor, presença de indivíduos suscetíveis e intenso movimento de turistas.

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Title: Zika virus displacement by a chikungunya outbreak in Recife, Brazil
Authors: Magalhaes, Tereza; Braga, Cynthia; Cordeiro, Marli T.; Oliveira, Andre L. S.; Castanha, Priscila M. S.; Maciel, Ana Paula R.; Amancio, Nathalia M. L.; Gouveia, Pollyanne N.; Peixoto-da-Silva, Valter J.; Peixoto, Thaciana F. L.; Britto, Helena; Lima, Priscilla V.; Lima, Andreza R. S.; Rosenberger, Kerstin D.; Jaenisch, Thomas; Marques, Ernesto T. A.

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Title: Central Nervous System Effects of Intrauterine Zika Virus Infection: A Pictorial Review
Authors: Ribeiro, Bianca Guedes; Werner, Heron; Lopes, Flávia P. P. L.; Cruz, L. Celso Hygino da; Fazecas, Tatiana M.; Daltro, Pedro A. N.; Nogueira, Renata A.
Description: Comentários em vídeo dos autores disponíveis em: https://www.youtube.com/watch?v=3OZ4rLAUHfw

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by Craig J. Bierle, Claudia Fernández-Alarcón, Nelmary Hernandez-Alvarado, Jason C. Zabeli, Bradley C. Janus, Dira S. Putri, Mark R. Schleiss

Primary Zika virus (ZIKV) infections that occur during pregnancy can cause spontaneous abortion and profoundly disrupt fetal development. While the full range of developmental abnormalities associated with congenital Zika syndrome is not yet known, severe cases of the syndrome can present with microcephaly, extensive neurologic and ocular damage, and pronounced joint malformations. Animal models that accurately recapitulate congenital Zika syndrome are urgently needed for vaccine development and for the study of ZIKV pathogenesis. As guinea pigs have successfully been used to model transplacental infections by cytomegalovirus, syphilis, and Listeria monocytogenes, we sought to test whether ZIKV could productively infect guinea pigs and whether viral transmission with attendant fetal pathology would occur after a mid-gestation viral challenge. We found that guinea pig cells supported ZIKV replication in vitro. Experimental infection of non-pregnant animals did not result in overt disease but low-level, detectable viremia was observed. When pregnant guinea pigs were challenged with ZIKV at between 18 and 21 days gestational age, ZIKV was not detected in maternal or pup blood, plasma, or tissues and no significant differences in maternal weight gain or pup size were observed following challenge. Nonetheless, a robust antibody response against ZIKV was detected in both the pups and dams. These results suggest that, while guinea pigs can model aspects of the immune response to ZIKV infection during pregnancy, naturally circulating ZIKV strains are not pathogenic during the pregnancy of immunocompetent guinea pigs and do not interfere with normal pup development.

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by Felipe J. Colón-González, Carlos A. Peres, Christine Steiner São Bernardo, Paul R. Hunter, Iain R. Lake
Background Zika is one of the most challenging emergent vector-borne diseases, yet its future public health impact remains unclear. Zika was of little public health concern until recent reports of its association with congenital syndromes. By 3 August 2017 ∼217,000 Zika cases and ∼3,400 cases of associated congenital syndrome were reported in Latin America and the Caribbean. Some modelling exercises suggest that Zika virus infection could become endemic in agreement with recent declarations from the The World Health Organisation. Methodology/Principal findings We produced high-resolution spatially-explicit projections of Zika cases, associated congenital syndromes and monetary costs for Latin America and the Caribbean now that the epidemic phase of the disease appears to be over. In contrast to previous studies which have adopted a modelling approach to map Zika potential, we project case numbers using a statistical approach based upon reported dengue case data as a Zika surrogate. Our results indicate that ∼12.3 (0.7–162.3) million Zika cases could be expected across Latin America and the Caribbean every year, leading to ∼64.4 (0.2–5159.3) thousand cases of Guillain-Barré syndrome and ∼4.7 (0.0–116.3) thousand cases of microcephaly. The economic burden of these neurological sequelae are estimated to be USD ∼2.3 (USD 0–159.3) billion per annum. Conclusions/Significance Zika is likely to have significant public health consequences across Latin America and the Caribbean in years to come. Our projections inform regional and federal health authorities, offering an opportunity to adapt to this public health challenge.

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Title: Prevalência e Incidência de Infecção pelo Vírus da Dengue em uma Comunidade Urbana: Um Estudo de Coorte
Authors: Tavares, Aline da Silva; Kikuti, Mariana; Paploski, Igor Adolfo Dexheimer; Silva, Monaise Madalena Oliveira e; Cruz, Jaqueline Silva; Reis, Mitermayer Galvão dos; Ribeiro, Guilherme Sousa
Abstract: Introdução: Nos últimos 25 anos a dengue reemergiu como um dos maiores problemas de
saúde pública do Brasil. A formulação de políticas públicas para prevenção e controle da
dengue, inclusive sobre a introdução de uma vacina, depende de um melhor entendimento
sobre a dinâmica de transmissão do vírus no país. Apesar disso, até o presente, poucos estudos
utilizaram dados primários para estimar a incidência e identificar grupos de risco para
infecções pelo vírus da dengue no Brasil.

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by Jung-Seok Lee, Vittal Mogasale, Jacqueline K. Lim, Mabel Carabali, Kang-Sung Lee, Chukiat Sirivichayakul, Duc Anh Dang, Diana Cristina Palencia-Florez, Thi Hien Anh Nguyen, Arthorn Riewpaiboon, Pornthep Chanthavanich, Luis Villar, Brian A. Maskery, Andrew Farlow
Background Dengue fever is a major public health concern in many parts of the tropics and subtropics. The first dengue vaccine has already been licensed in six countries. Given the growing interests in the effective use of the vaccine, it is critical to understand the economic burden of dengue fever to guide decision-makers in setting health policy priorities. Methods/Principal findings A standardized cost-of-illness study was conducted in three dengue endemic countries: Vietnam, Thailand, and Colombia. In order to capture all costs during the entire period of illness, patients were tested with rapid diagnostic tests on the first day of their clinical visits, and multiple interviews were scheduled until the patients recovered from the current illness. Various cost items were collected such as direct medical and non-medical costs, indirect costs, and non-out-of-pocket costs. In addition, socio-economic factors affecting disease severity were also identified by adopting a logit model. We found that total cost per episode ranges from $141 to $385 for inpatient and from $40 to $158 outpatient, with Colombia having the highest and Thailand having the lowest. The percentage of the private economic burden of dengue fever was highest in the low-income group and lowest in the high-income group. The logit analyses showed that early treatment, higher education, and better knowledge of dengue disease would reduce the probability of developing more severe illness. Conclusions/Significance The cost of dengue fever is substantial in the three dengue endemic countries. Our study findings can be used to consider accelerated introduction of vaccines into the public and private sector programs and prioritize alternative health interventions among competing health problems. In addition, a community would be better off by propagating the socio-economic factors identified in this study, which may prevent its members from developing severe illness in the long run.

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by Elena Lorente, Alejandro Barriga, Juan García-Arriaza, François A. Lemonnier, Mariano Esteban, Daniel López
Background The adaptive cytotoxic T lymphocyte (CTL)-mediated immune response is critical for clearance of many viral infections. These CTL recognize naturally processed short viral antigenic peptides bound to human leukocyte antigen (HLA) class I molecules on the surface of infected cells. This specific recognition allows the killing of virus-infected cells. The T cell immune T cell response to Chikungunya virus (CHIKV), a mosquito-borne Alphavirus of the Togaviridae family responsible for severe musculoskeletal disorders, has not been fully defined; nonetheless, the importance of HLA class I-restricted immune response in this virus has been hypothesized. Methodology/Principal findings By infection of HLA-A*0201-transgenic mice with a recombinant vaccinia virus that encodes the CHIKV structural polyprotein (rVACV-CHIKV), we identified the first human T cell epitopes from CHIKV. These three novel 6K transmembrane protein-derived epitopes are presented by the common HLA class I molecule, HLA-A*0201. One of these epitopes is processed and presented via a complex pathway that involves proteases from different subcellular locations. Specific chemical inhibitors blocked these events in rVACV-CHIKV-infected cells. Conclusions/Significance Our data have implications not only for the identification of novel Alphavirus and Togaviridae antiviral CTL responses, but also for analyzing presentation of antigen from viruses of different families and orders that use host proteinases to generate their mature envelope proteins.

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Title: Trabalho prescrito e trabalho real nas ações de controle vetorial do Aedes Aegypti: nocividade frente ao uso de produtos químicos formulados à base de ingredientes ativos de agrotóxicos
Authors: Guedes, Clenio Azevedo
Abstract: A expansão das arboviroses transmitidas por mosquitos do gênero Aedes, tais como Dengue, Chikungunya e Zika, tem sido observada de modo crescente em vários países recentemente. O modelo de controle das arboviroses preconizado pelo Ministério da Saúde do Brasil é pautado no uso de produtos químicos para o controle do vetor, não contemplando efetivas medidas de segurança para os Agentes de Saúde Ambiental e Combate às Endemias (ASACE). O presente estudo buscou avaliar como são percebidas as nocividades para a saúde dos trabalhadores que atuam no controle do Aedes aegypti devido à exposição a substâncias químicas. Foi realizado um estudo de caso com os ASACE do município do Recife mediante o método da Análise Coletiva do Trabalho (ACT). Foi evidenciado que, nas ações de controle vetorial, os ASACEs se expõem a substâncias químicas durante o preparo da calda, aplicação, manutenção/limpeza do aplicador costal, no armazenamento e transporte dessas substâncias e pelo contato com equipamentos de proteção individual (EPI) contaminados. Não há uma política de educação continuada para o manuseio de produtos químicos. Os trabalhadores não recebem os EPI completos, adequados e dentro do prazo de validade, tampouco treinamento para seu uso. O controle periódico da saúde não é desenvolvido, e os trabalhadores revelaram queixas de saúde que podem estar relacionadas com a exposição aos produtos químicos utilizados. As diferenças existentes entre o trabalho prescrito e o real foram explicitadas na visão crítica dos trabalhadores, que compreendem que o uso dos venenos, além de não resolver os problemas das arboviroses, pode afetar sua saúde, a da população e o ambiente. A discrepância entre o trabalho prescrito e o real também se evidenciou na precarização do trabalho, que apresenta diversas situações de risco não consideradas pelo sistema de saúde local, mas que são percebidas pelos trabalhadores, gerando descontentamento e insegurança (AU)

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by Rogelio Danis-Lozano, Esteban Eduardo Díaz-González, Karina del Carmen Trujillo-Murillo, Sandra Caballero-Sosa, Jesús Sepúlveda-Delgado, Iliana Rosalía Malo-García, Luis Miguel Canseco-Ávila, Luis Manuel Salgado-Corsantes, Sergio Domínguez-Arrevillaga, Raúl Torres-Zapata, Omar Gómez-Cruz, Ildefonso Fernández-Salas
Background The emerging chikungunya virus (CHIKV), is an arbovirus causing intense outbreaks in North America. The situation in Mexico is alarming, and CHIKV threatens to spread further throughout North America. Clinical and biological features of CHIKF outbreaks in Mexico have not been well described; thus, we conducted a cross sectional study of a CHIKV outbreak in Chiapas, Southern Mexico to further characterize these features. Methodology/Principal findings We collected blood samples from patients suspected of having chikungunya fever (CHIKF) who presented to Clinical Hospital ISSSTE Dr. Roberto Nettel in Tapachula, Chiapas, Mexico. In addition to the clinical examination, real-time polymerase chain reaction (PCR) standardized for the Asian Chikungunya lineage and/or enzyme-linked immunosorbent assay for immunoglobulin M (IgM) were used to confirm CHIKV diagnosis. Of a total of 850 patients who presented with probably CHIKV at Hospital “Dr. Roberto Nettel”, 112 probable CHIKF cases were enrolled in this study from November 2014- June 2015, of which 95 patients (84.8%) were CHIKV positive and 17 were negative (15.2%). Of these 95 CHIKV positive patients, 62 were positive by real-time reverse transcriptase PCR (+qRT-PCR); and 33 were seropositive to +IgM with a negative qRT-PCR. The most frequent symptoms reported were fever (100%), headache (82.3%), polyarthralgia (72.1%), and exanthem (82.3%). Biological abnormalities observed during CHIKV infection were lymphopenia (41.1%), leukopenia (51.6%), elevated transaminases (30.5%-46.3%) and high LDH (46.3%) and CRP (60.0%). Conclusion Clinical and biological data obtained from this study is providing more useful information for benchmarking purposes with outbreaks from different parts of the world and would be helpful for better patient care and treatment.

PLOS ONE -

Title: Seminário Oficina Conjunta UNASUR/CPLP de atualização científica e tecnológica sobre febre amarela e outras arboviroses emergentes e reemergentes - Dia 4/10
Authors: Alves, Manoella; Parra, Edgar Alberto; Guimarães, Rosane Cuber; Zabulon, Yoti; Chiang, Jannifer Oliveira; Lima, Luiz Alberto dos S.; Martins, Reinaldo de Menezes; Vasconcelos, Jocelyne Neto de
Abstract: Organizado pela Fiocruz, através da Coordenação de Vigilância e Laboratórios de Referência e do Centro de Relações internacionais em Saúde, tem o objetivo de fortalecer a capacidade dos Institutos Nacionais de Saúde da UNASUR e da CPLP e dos Ministérios da Saúde, para prestação de serviços e geração de conhecimentos e formação de recursos humanos necessários à prevenção e o controle de emergências sanitárias, com particular referência à febre amarela e outras arboviroses, emergente e reemergentes.

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by Lopamudra Dey, Anirban Mukhopadhyay

PLOS Neglected Tropical Diseases -

by Mayra Diosa-Toro, Liliana Echavarría-Consuegra, Jacky Flipse, Geysson Javier Fernández, Joost Kluiver, Anke van den Berg, Silvio Urcuqui-Inchima, Jolanda M. Smit
Background Due to the high burden of dengue disease worldwide, a better understanding of the interactions between dengue virus (DENV) and its human host cells is of the outmost importance. Although microRNAs modulate the outcome of several viral infections, their contribution to DENV replication is poorly understood. Methods and principal findings We investigated the microRNA expression profile of primary human macrophages challenged with DENV and deciphered the contribution of microRNAs to infection. To this end, human primary macrophages were challenged with GFP-expressing DENV and sorted to differentiate between truly infected cells (DENV-positive) and DENV-exposed but non-infected cells (DENV-negative cells). The miRNAome was determined by small RNA-Seq analysis and the effect of differentially expressed microRNAs on DENV yield was examined. Five microRNAs were differentially expressed in human macrophages challenged with DENV. Of these, miR-3614-5p was found upregulated in DENV-negative cells and its overexpression reduced DENV infectivity. The cellular targets of miR-3614-5p were identified by liquid chromatography/mass spectrometry and western blot. Adenosine deaminase acting on RNA 1 (ADAR1) was identified as one of the targets of miR-3614-5p and was shown to promote DENV infectivity at early time points post-infection. Conclusion/Significance Overall, miRNAs appear to play a limited role in DENV replication in primary human macrophages. The miRNAs that were found upregulated in DENV-infected cells did not control the production of infectious virus particles. On the other hand, miR-3614-5p, which was upregulated in DENV-negative macrophages, reduced DENV infectivity and regulated ADAR1 expression, a protein that facilitates viral replication.

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by Margus Varjak, Claire L. Donald, Timothy J. Mottram, Vattipally B. Sreenu, Andres Merits, Kevin Maringer, Esther Schnettler, Alain Kohl

RNA interference (RNAi) controls arbovirus infections in mosquitoes. Two different RNAi pathways are involved in antiviral responses: the PIWI-interacting RNA (piRNA) and exogenous short interfering RNA (exo-siRNA) pathways, which are characterized by the production of virus-derived small RNAs of 25–29 and 21 nucleotides, respectively. The exo-siRNA pathway is considered to be the key mosquito antiviral response mechanism. In Aedes aegypti-derived cells, Zika virus (ZIKV)-specific siRNAs were produced and loaded into the exo-siRNA pathway effector protein Argonaute 2 (Ago2); although the knockdown of Ago2 did not enhance virus replication. Enhanced ZIKV replication was observed in a Dcr2-knockout cell line suggesting that the exo-siRNA pathway is implicated in the antiviral response. Although ZIKV-specific piRNA-sized small RNAs were detected, these lacked the characteristic piRNA ping-pong signature motif and were bound to Ago3 but not Piwi5 or Piwi6. Silencing of PIWI proteins indicated that the knockdown of Ago3, Piwi5 or Piwi6 did not enhance ZIKV replication and only Piwi4 displayed antiviral activity. We also report that the expression of ZIKV capsid (C) protein amplified the replication of a reporter alphavirus; although, unlike yellow fever virus C protein, it does not inhibit the exo-siRNA pathway. Our findings elucidate ZIKV-mosquito RNAi interactions that are important for understanding its spread.

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by Pi Guo, Tao Liu, Qin Zhang, Li Wang, Jianpeng Xiao, Qingying Zhang, Ganfeng Luo, Zhihao Li, Jianfeng He, Yonghui Zhang, Wenjun Ma
Background In China, dengue remains an important public health issue with expanded areas and increased incidence recently. Accurate and timely forecasts of dengue incidence in China are still lacking. We aimed to use the state-of-the-art machine learning algorithms to develop an accurate predictive model of dengue. Methodology/Principal findings Weekly dengue cases, Baidu search queries and climate factors (mean temperature, relative humidity and rainfall) during 2011–2014 in Guangdong were gathered. A dengue search index was constructed for developing the predictive models in combination with climate factors. The observed year and week were also included in the models to control for the long-term trend and seasonality. Several machine learning algorithms, including the support vector regression (SVR) algorithm, step-down linear regression model, gradient boosted regression tree algorithm (GBM), negative binomial regression model (NBM), least absolute shrinkage and selection operator (LASSO) linear regression model and generalized additive model (GAM), were used as candidate models to predict dengue incidence. Performance and goodness of fit of the models were assessed using the root-mean-square error (RMSE) and R-squared measures. The residuals of the models were examined using the autocorrelation and partial autocorrelation function analyses to check the validity of the models. The models were further validated using dengue surveillance data from five other provinces. The epidemics during the last 12 weeks and the peak of the 2014 large outbreak were accurately forecasted by the SVR model selected by a cross-validation technique. Moreover, the SVR model had the consistently smallest prediction error rates for tracking the dynamics of dengue and forecasting the outbreaks in other areas in China. Conclusion and significance The proposed SVR model achieved a superior performance in comparison with other forecasting techniques assessed in this study. The findings can help the government and community respond early to dengue epidemics.

PLOS Neglected Tropical Diseases -

Title: On the origin and timing of Zika virus introduction in Brazil
Authors: Massad, E; Burattini, M Nascimento; Khan, K; Struchiner, C J; Coutinho, F A B; Wilder-Smith, A

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Title: Full-length infectious clone of a low passage dengue virus serotype 2 from Brazil
Authors: Santos, Jefferson José da Silva; Magalhães, Tereza; Silva Junior, José Valter Joaquim; Silva, Andréa Nazaré Monteiro Rangel da; Cordeiro, Marli Tenório; Gil, Laura Helena Vega Gonzales

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by John F. Arboleda Alzate, Izabela A. Rodenhuis-Zybert, Juan C. Hernández, Jolanda M. Smit, Silvio Urcuqui-Inchima
Background Severe dengue disease is associated with high viral loads and overproduction of pro-inflammatory cytokines, suggesting impairment in the control of dengue virus (DENV) and the mechanisms that regulate cytokine production. Vitamin D3 has been described as an important modulator of immune responses to several pathogens. Interestingly, increasing evidence has associated vitamin D with decreased DENV infection and early disease recovery, yet the molecular mechanisms whereby vitamin D reduces DENV infection are not well understood. Methods and principal findings Macrophages represent important cell targets for DENV replication and consequently, they are key drivers of dengue disease. In this study we evaluated the effect of vitamin D3 on the differentiation of monocyte-derived macrophages (MDM) and their susceptibility and cytokine response to DENV. Our data demonstrate that MDM differentiated in the presence of vitamin D3 (D3-MDM) restrict DENV infection and moderate the classical inflammatory cytokine response. Mechanistically, vitamin D3-driven differentiation led to reduced surface expression of C-type lectins including the mannose receptor (MR, CD206) that is known to act as primary receptor for DENV attachment on macrophages and to trigger of immune signaling. Consequently, DENV bound less efficiently to vitamin D3-differentiated macrophages, leading to lower infection. Interestingly, IL-4 enhanced infection was reduced in D3-MDM by restriction of MR expression. Moreover, we detected moderate secretion of TNF-α, IL-1β, and IL-10 in D3-MDM, likely due to less MR engagement during DENV infection. Conclusions/Significance Our findings reveal a molecular mechanism by which vitamin D counteracts DENV infection and progression of severe disease, and indicates its potential relevance as a preventive or therapeutic candidate.

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Title: Coinfections of Zika and Chikungunya Viruses in Bahia, Brazil, Identified by Metagenomic Next-Generation Sequencing
Authors: Sardi, Silvia Ines; Somasekar, Sneha; Naccache, Samia N; Bandeira, Antonio Carlos; Tauro, Laura Beatriz; Campos, Gubio Soares; Chiu, Charles Y

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Title: Antibody-based assay discriminates Zika virus infection from other flaviviruses
Authors: Balmaseda, Angel; Stettler, Karin; Medialdea-Carrera, Raquel; Collado, Damaris; Jin, Xia; Zambrana, José Victor; Jaconi, Stefano; Cameroni, Elisabetta; Saborio, Saira; Rovida, Francesca; Percivalle, Elena; Ijaz, Samreen; Dicks, Steve; Ushiro-Lumb, Ines; Barzon, Luisa; Siqueira, Patricia; Brown, David W. G.; Baldanti, Fausto; Tedder, Richard; Zambon, Maria; Filippis, A. M. Bispo de; Harris, Eva; Corti, Davide

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Title: Heparin removal by ecteola-cellulose pre-treatment enables the use of plasma samples for accurate measurement of anti-Yellow fever virus neutralizing antibodies.
Authors: Azevedo, Ana Carolina Campi; Pascoal, Vanessa Peruhype Magalhães; Reis, Jordana Grazziela Coelho dos; Pereira, Christiane Costa; Yamamura, Anna Yoshida; Lima, Sheila Maria Barbosa de; Simões, Marisol; Campos, Fernanda Magalhães Freire; Tonini, Aline de Castro Zacche; Lemos, Elenice Moreira; Brum, Ricardo Cristiano; Noronha, Tatiana Guimarães de; Freire, Marcos Silva; Maia, Maria de Lourdes Sousa; Camacho, Luiz Antônio Bastos; Rios, Maria; Chancey, Caren; Romano, Alessandro; Domingues, Carla Magda; Carvalho, Andréa Teixeira de; Martins Filho, Olindo Assis

Arca Fiocruz -

Title: Zika virus transmission to mouse ear by mosquito bite: a laboratory model that replicates the natural transmission process
Authors: Secundino, Nagila Francinete Costa; Chaves, Barbara Aparecida; Orfano, Alessandra Silva; Silveira, Karine Renata Dias; Rodrigues, Nilton Barnabe; Campolina, Thais Bonifácio; Pimenta, Rafael Nacif; Martinez-Villegas, Luiz Eduardo; Silva, Breno Melo; Lacerda, Marcus Vinícius Guimarães; Norris, Douglas Eric; Pimenta, Paulo Filemon Paolucci

Arca Fiocruz -

by Jelte Elsinga, Martin P. Grobusch, Adriana Tami, Izzy Gerstenbluth, Ajay Bailey
Introduction Chikungunya is an emerging public health problem in tropical and subtropical regions, due to ongoing transmission and its incapacitating acute disease phase, and chronic sequelae. The disease is responsible for a major impact on Health Related Quality of Life (HRQoL), which may last several years. To our knowledge, this study is the first qualitative examination of HRQoL and coping strategies of chikungunya-infected individuals. Methods Qualitative research methods consisted of 20 in-depth interviews and seven Focus Group Discussions (FGDs), n = 50. Analysis was based on the principles of the grounded theory. Results Different impacts on HRQoL were reported. The physical and emotional domains of the HRQoL were mainly affected by chikungunya, while social and individual financial consequences were limited. Individual financial impact was limited through the universal health care program of Curaçao. Long-term lingering musculoskeletal and other manifestations caused significant pain and limited mobility. Hence, participants experienced dependency, impairment of normal daily life activities, moodiness, hopelessness, a change of identity, and insecurity about their future. The unpredictable nature and consequences of chikungunya gave rise to various coping strategies. Problem-focused coping styles led to higher uptake of medical care and were linked to more negative impact of HRQoL, whereas emotional coping strategies focusing on acceptance of the situation were linked to less uptake of medical care and more positive impact on HRQoL. Conclusions This study provides an in-depth understanding of acute and long-term HRQoL impact of chikungunya. The results can better inform health promotion policies and interventions. Messages to the public should focus on promoting healthy and efficient coping strategies, in order to prevent additional stress in affected individuals.

PLOS Neglected Tropical Diseases -

by Suellen de Oliveira, Daniel Antunes Maciel Villela, Fernando Braga Stehling Dias, Luciano Andrade Moreira, Rafael Maciel de Freitas
Background Wolbachia has been deployed in several countries to reduce transmission of dengue, Zika and chikungunya viruses. During releases, Wolbachia-infected females are likely to lay their eggs in local available breeding sites, which might already be colonized by local Aedes sp. mosquitoes. Therefore, there is an urgent need to estimate the deleterious effects of intra and interspecific larval competition on mosquito life history traits, especially on the duration of larval development time, larval mortality and adult size. Methodology/principal findings Three different mosquito populations were used: Ae. aegypti infected with Wolbachia (wMelBr strain), wild Ae. aegypti and wild Ae. albopictus. A total of 21 treatments explored intra and interspecific larval competition with varying larval densities, species proportions and food levels. Each treatment had eight replicates with two distinct food levels: 0.25 or 0.50 g of Chitosan and fallen avocado leaves. Overall, overcrowding reduced fitness correlates of the three populations. Ae. albopictus larvae presented lower larval mortality, shorter development time to adult and smaller wing sizes than Ae. aegypti. The presence of Wolbachia had a slight positive effect on larval biology, since infected individuals had higher survivorship than uninfected Ae. aegypti larvae. Conclusions/significance In all treatments, Ae. albopictus outperformed both wild Ae. aegypti and the Wolbachia-infected group in larval competition, irrespective of larval density and the amount of food resources. The major force that can slow down Wolbachia invasion is the population density of wild mosquitoes. Given that Ae. aegypti currently dominates in Rio, in comparison with Ae. albopictus frequency, additional attention must be given to the population density of Ae. aegypti during releases to increase the likelihood of Wolbachia invasion.

PLOS Neglected Tropical Diseases -

by Erin M. McDonald, Nisha K. Duggal, Aaron C. Brault

The Spondweni serogroup of viruses (Flaviviridae, Flavivirus) is comprised of Spondweni virus (SPONV) and Zika virus (ZIKV), which are mosquito-borne viruses capable of eliciting human disease. Numerous cases of ZIKV sexual transmission in humans have been documented following the emergence of the Asian genotype in the Americas. The African ZIKV genotype virus was previously implicated in the first reported case of ZIKV sexual transmission. Reports of SPONV infection in humans have been associated with non-specific febrile illness, but no association with sexual transmission has been reported. In order to assess the relative efficiency of sexual transmission of different ZIKV strains and the potential capacity of SPONV to be sexually transmitted, viral loads in the male reproductive tract and in seminal fluids were assessed in interferon α/β and –γ receptor deficient (AG129) mice. Male mice were inoculated subcutaneously with Asian genotype ZIKV strains PRVABC59 (Puerto Rico, 2015), FSS13025 (Cambodia, 2010), or P6-740 (Malaysia, 1966); African genotype ZIKV strain DakAr41524 (Senegal, 1984); or SPONV strain SAAr94 (South Africa, 1955). Infectious virus was detected in 60–72% of ejaculates collected from AG129 mice inoculated with ZIKV strains. In contrast, only 4% of ejaculates from SPONV-inoculated AG129 males were found to contain infectious virus, despite viral titers in the testes that were comparable to those of ZIKV-inoculated mice. Based on these results, future studies should be undertaken to assess the role of viral genetic determinants and host tropism that dictate the differential sexual transmission potential of ZIKV and SPONV.

PLOS Neglected Tropical Diseases -

Title: Mobilização Sócio-Educativa para Prevenção e Controle da Dengue
Authors: Souza, Kathleen Ribeiro; Guimarães, Isabel; Morais, Geruza; Monte Alegre, Adriano; Santos, Maria Lígia Rangel; Ribeiro, Guilherme de Souza; Silva, Luciano Kalabric
Abstract: Introdução: O mosquito Aedes aegypti é o principal vetor da dengue e outras arboviroses no ambiente urbano. O presente
estudo tem por objetivo desenvolver ações de mobilização sócio-educativas que resultem num controle vetorial mais efetivo por
parte da comunidade. Material e Métodos: Foram selecionadas duas áreas (estrato 299 e 302) em Salvador-BA, com
características socio-demográficas, urbanísticas e IIP históricos semelhantes (> 4%).

Arca Fiocruz -

by Shengzhang Dong, Velmurugan Balaraman, Asher M. Kantor, Jingyi Lin, DeAna G. Grant, Nicole L. Held, Alexander W. E. Franz

In the mosquito, the midgut epithelium is the initial tissue to become infected with an arthropod-borne virus (arbovirus) that has been acquired from a vertebrate host along with a viremic bloodmeal. Following its replication in midgut epithelial cells, the virus needs to exit the midgut and infect secondary tissues including the salivary glands before it can be transmitted to another vertebrate host. The viral exit mechanism from the midgut, the midgut escape barrier (MEB), is poorly understood although it is an important determinant of mosquito vector competence for arboviruses. Using chikungunya virus (CHIKV) as a model in Aedes aegypti, we demonstrate that the basal lamina (BL) of the extracellular matrix (ECM) surrounding the midgut constitutes a potential barrier for the virus. The BL, predominantly consisting of collagen IV and laminin, becomes permissive during bloodmeal digestion in the midgut lumen. Bloodmeal digestion, BL permissiveness, and CHIKV dissemination are coincident with increased collagenase activity, diminished collagen IV abundance, and BL shredding in the midgut between 24–32 h post-bloodmeal. This indicates that there may be a window-of-opportunity during which the MEB in Ae. aegypti becomes permissive for CHIKV. Matrix metalloproteinases (MMPs) are the principal extracellular endopeptidases responsible for the degradation/remodeling of the ECM including the BL. We focused on Ae. aegypti (Ae)MMP1, which is expressed in midgut epithelial cells, is inducible upon bloodfeeding, and shows collagenase (gelatinase) activity. However, attempts to inhibit AeMMP activity in general or specifically that of AeMMP1 did not seem to affect its function nor produce an altered midgut escape phenotype. As an alternative, we silenced and overexpressed the Ae. aegypti tissue inhibitor of metalloproteinases (AeTIMP) in the mosquito midgut. AeTIMP was highly upregulated in the midgut during bloodmeal digestion and was able to inhibit MMP activity in vitro. Bloodmeal-inducible, midgut-specific overexpression of AeTIMP or its expression via a recombinant CHIKV significantly increased midgut dissemination rates of the virus. Possibly, AeTIMP overexpression affected BL degradation and/or restoration thereby increasing the midgut dissemination efficiency of the virus.

PLOS Neglected Tropical Diseases -

by Brian J. Johnson, Sara N. Mitchell, Christopher J. Paton, Jessica Stevenson, Kyran M. Staunton, Nigel Snoad, Nigel Beebe, Bradley White, Scott A. Ritchie
Background Recent interest in male-based sterile insect technique (SIT) and incompatible insect technique (IIT) to control Aedes aegypti and Aedes albopictus populations has revealed the need for an economical, rapid diagnostic tool for determining dispersion and mating success of sterilized males in the wild. Previous reports from other insects indicated rhodamine B, a thiol-reactive fluorescent dye, administered via sugar-feeding can be used to stain the body tissue and seminal fluid of insects. Here, we report on the adaptation of this technique for male Ae. aegypti to allow for rapid assessment of competitiveness (mating success) during field releases. Methodology/Principle findings Marking was achieved by feeding males on 0.1, 0.2, 0.4 or 0.8% rhodamine B (w/v) in 50% honey solutions during free flight. All concentrations produced >95% transfer to females and successful body marking after 4 days of feeding, with 0.4 and 0.8% solutions producing the longest-lasting body marking. Importantly, rhodamine B marking had no effect on male mating competitiveness and proof-of-principle field releases demonstrated successful transfer of marked seminal fluid to females under field conditions and recapture of marked males. Conclusions/Significance These results reveal rhodamine B to be a potentially useful evaluation method for male-based SIT/IIT control strategies as well as a viable body marking technique for male-based mark-release-recapture experiments without the negative side-effects of traditional marking methods. As a standalone method for use in mating competitiveness assays, rhodamine B marking is less expensive than PCR (e.g. paternity analysis) and stable isotope semen labelling methods and less time-consuming than female fertility assays used to assess competitiveness of sterilised males.

PLOS Neglected Tropical Diseases -