Monitoramento das Produções

by Olivia C. Winokur, Bradley J. Main, Jay Nicholson, Christopher M. Barker

Since Zika virus (ZIKV) emerged as a global human health threat, numerous studies have pointed to Aedes aegypti as the primary vector due to its high competence and propensity to feed on humans. The majority of vector competence studies have been conducted between 26–28°C, but arboviral extrinsic incubation periods (EIPs), and therefore transmission efficiency, are known to be affected strongly by temperature. To better understand the relationship between ZIKV EIPs and temperature, we evaluated the effect of adult mosquito exposure temperature on ZIKV infection, dissemination, and transmission in Ae. aegypti at four temperatures: 18°C, 21°C, 26°C, and 30°C. Mosquitoes were exposed to viremic mice infected with a 2015 Puerto Rican ZIKV strain, and engorged mosquitoes were sorted into the four temperatures with 80% RH and constant access to 10% sucrose. ZIKV infection, dissemination, and transmission rates were assessed via RT-qPCR from individual mosquito bodies, legs and wings, and saliva, respectively, at three to five time points per temperature from three to 31 days, based on expectations from other flavivirus EIPs. The median time from ZIKV ingestion to transmission (median EIP, EIP50) at each temperature was estimated by fitting a generalized linear mixed model for each temperature. EIP50 ranged from 5.1 days at 30°C to 24.2 days at 21°C. At 26°C, EIP50 was 9.6 days. At 18°C, only 15% transmitted by day 31 so EIP50 could not be estimated. This is among the first studies to characterize the effects of temperature on ZIKV EIP in Ae. aegypti, and the first to do so based on feeding of mosquitoes on a live, viremic host. This information is critical for modeling ZIKV transmission dynamics to understand geographic and seasonal limits of ZIKV risk; it is especially relevant for determining risk in subtropical regions with established Ae. aegypti populations and relatively high rates of return travel from the tropics (e.g. California or Florida), as these regions typically experience cooler temperature ranges than tropical regions.

by Jörg Blessmann, Yvonne Winkelmann, Latdamone Keoviengkhone, Vatsana Sopraseuth, Simone Kann, Jessica Hansen, Hussein El Halas, Petra Emmerich, Jonas Schmidt-Chanasit, Herbert Schmitz, Angela Mika, Christina Deschermeier
Background Rapid tests detecting both dengue virus (DENV) NS1 antigen and anti-DENV IgM and IgG antibodies facilitate diagnosis of dengue fever (DF) in resource-poor settings. Methodology/principal findings 92 acute phase serum samples from patients with a PCR-confirmed DENV infection collected in Lao People’s Democratic Republic (Lao PDR) in 2013 and 2015 were analyzed with the SD Bioline Dengue Duo test. A subset of 74 samples was additionally tested with the Platelia NS1 antigen test, the Panbio DENV μ-capture ELISA and the Panbio DENV IgG ELISA. IgM seroconversion was assayed using follow-up samples of 35 patients collected in the convalescent phase. 57.6%, 22.8% and 44.6% of acute phase serum samples tested positive in the SD Bioline Dengue Duo NS1, IgM, and IgG test, respectively. Diagnostic sensitivity of the SD Bioline Dengue Duo NS1 test strongly correlated with viral load, decreased rapidly over the acute phase of the disease, and was significantly reduced in presence of high anti-DENV IgG antibody titers resulting from secondary DENV infection. While a good concordance (Cohen’s kappa 0.78) was found between the SD Bioline Dengue Duo NS1 test and the Platelia NS1 antigen ELISA, both the SD Bioline Dengue Duo IgM and IgG test displayed a significantly lower sensitivity than the corresponding ELISA tests. Conclusions/significance The SD Bioline Dengue Duo test is a valuable tool for diagnosis of DENV infections especially when analyzing early acute phase samples with high viral load. Nevertheless, in endemic areas, where secondary flavivirus infections are common, diagnostic sensitivity of the NS1 and IgM test components may be compromised.

by Farah Z. Vera-Maloof, Karla Saavedra-Rodriguez, Rosa P. Penilla-Navarro, Americo D. Rodriguez-Ramirez, Felipe Dzul, Pablo Manrique-Saide, William C. Black IV
Background Resistance to pyrethroid insecticides in Aedes aegypti has become widespread after almost two decades of the frequent use of these pesticides to reduce arbovirus transmission. Despite this resistance, pyrethroids continue to be used because they are relatively inexpensive and have low human toxicity. Resistance management has been proposed as a way to retain the use of pyrethroids in natural populations. A key component of resistance management is the assumption that negative fitness is associated with resistance alleles such that resistance alleles will decline in frequency when the insecticides are removed. At least three studies in Ae. aegypti have demonstrated a decrease in pyrethroid resistance once the insecticide has been removed. Methods/Principal findings The present study aims to evaluate variation in the loss of pyrethroid resistance among newly established laboratory populations of Ae. aegypti from Mexico. Eight field collections were maintained for up to eight generations, and we recorded changes in the frequencies of the mutations at the V1,016I locus and at the F1,534C locus in the voltage-gated sodium channel gene (VGSC). I1,016 and C1,534 confer resistance. We also examined resistance ratios (RR) with type 1 and 2 pyrethroids. Conclusions/Significance We demonstrate that, in general, the frequency of the Ae. aegypti pyrethroid-resistance alleles I1,016 and C1,534 decline when they are freed from pyrethroid pressure in the laboratory. However, the pattern of decline is strain dependent. In agreement with earlier studies, the RR was positively correlated with the frequencies of the resistance allele I1,016 and showed significant protection against permethrin, and deltamethrin, whereas F1,534C showed protection against permethrin but not against deltamethrin.

by Carolina da S. G. Pedrosa, Leticia R. Q. Souza, Tiago A. Gomes, Caroline V. F. de Lima, Pitia F. Ledur, Karina Karmirian, Jimena Barbeito-Andres, Marcelo do N. Costa, Luiza M. Higa, Átila D. Rossi, Maria Bellio, Amilcar Tanuri, Arnaldo Prata-Barbosa, Fernanda Tovar-Moll, Patricia P. Garcez, Flavio A. Lara, Renato J. R. Molica, Stevens K. Rehen

The northeast (NE) region of Brazil commonly goes through drought periods, which favor cyanobacterial blooms, capable of producing neurotoxins with implications for human and animal health. The most severe dry spell in the history of Brazil occurred between 2012 and 2016. Coincidently, the highest incidence of microcephaly associated with the Zika virus (ZIKV) outbreak took place in the NE region of Brazil during the same years. In this work, we tested the hypothesis that saxitoxin (STX), a neurotoxin produced in South America by the freshwater cyanobacteria Raphidiopsis raciborskii, could have contributed to the most severe Congenital Zika Syndrome (CZS) profile described worldwide. Quality surveillance showed higher cyanobacteria amounts and STX occurrence in human drinking water supplies of NE compared to other regions of Brazil. Experimentally, we described that STX doubled the quantity of ZIKV-induced neural cell death in progenitor areas of human brain organoids, while the chronic ingestion of water contaminated with STX before and during gestation caused brain abnormalities in offspring of ZIKV-infected immunocompetent C57BL/6J mice. Our data indicate that saxitoxin-producing cyanobacteria is overspread in water reservoirs of the NE and might have acted as a co-insult to ZIKV infection in Brazil. These results raise a public health concern regarding the consequences of arbovirus outbreaks happening in areas with droughts and/or frequent freshwater cyanobacterial blooms.

by Antoine Bertolotti, Marême Thioune, Sylvie Abel, Gilda Belrose, Isabelle Calmont, Raymond Césaire, Minerva Cervantes, Laurence Fagour, Émilie Javelle, Catherine Lebris, Fatiha Najioullah, Sandrine Pierre-François, Benoît Rozé, Marie Vigan, Cédric Laouénan, André Cabié, the Chronic Chikungunya working group of University Medical Center of Martinique
Background The chikungunya virus (CHIKV) is a re-emerging alphavirus that can cause chronic and potentially incapacitating rheumatic musculoskeletal disorders known as chronic chikungunya arthritis (CCA). We conducted a prospective cohort study of CHIKV-infected subjects during the 2013 chikungunya outbreak in Martinique. The aim of this study was to assess the prevalence of CCA at 12 months and to search for acute phase factors significantly associated with chronicity. Methodology/Principal findings A total of 193 patients who tested positive for CHIKV RNA via qRT-PCR underwent clinical investigations in the acute phase (

by Israel Guerrero-Arguero, Taalin R. Høj, E. Shannon Tass, Bradford K. Berges, Richard A. Robison

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes rash, fever and severe polyarthritis that can last for years in humans. Murine models display inflammation and macrophage infiltration only in the adjacent tissues at the site of inoculation, showing no signs of systemic polyarthritis. Monocyte-derived macrophages are one cell type suspected to contribute to a systemic CHIKV infection. The purpose of this study was to analyze differences in CHIKV infection in two different cell lines, human U937 and murine RAW264.7 monocyte derived macrophages. PMA-differentiated U937 and RAW264.7 macrophages were infected with CHIKV, and infectious virus production was measured by plaque assay and by reverse transcriptase quantitative PCR at various time points. Secreted cytokines in the supernatants were measured using cytometric bead arrays. Cytokine mRNA levels were also measured to supplement expression data. Here we show that CHIKV replicates more efficiently in human macrophages compared to murine macrophages. In addition, infected human macrophages produced around 10-fold higher levels of infectious virus when compared to murine macrophages. Cytokine induction by CHIKV infection differed between human and murine macrophages; IL-1, IL-6, IFN-γ, and TNF were significantly upregulated in human macrophages. This evidence suggests that CHIKV replicates more efficiently and induces a much greater pro-inflammatory cytokine profile in human macrophages, when compared to murine macrophages. This may shed light on the critical role that macrophages play in the CHIKV inflammatory response.

by Donald Salami, César Capinha, Maria do Rosário Oliveira Martins, Carla Alexandra Sousa

The spread of dengue through global human mobility is a major public health concern. A key challenge is understanding the transmission pathways and mediating factors that characterized the patterns of dengue importation into non-endemic areas. Utilizing a network connectivity-based approach, we analyze the importation patterns of dengue fever into European countries. Seven connectivity indices were developed to characterize the role of the air passenger traffic, seasonality, incidence rate, geographical proximity, epidemic vulnerability, and wealth of a source country, in facilitating the transport and importation of dengue fever. We used generalized linear mixed models (GLMMs) to examine the relationship between dengue importation and the connectivity indices while accounting for the air transport network structure. We also incorporated network autocorrelation within a GLMM framework to investigate the propensity of a European country to receive an imported case, by virtue of its position within the air transport network. The connectivity indices and dynamical processes of the air transport network were strong predictors of dengue importation in Europe. With more than 70% of the variation in dengue importation patterns explained. We found that transportation potential was higher for source countries with seasonal dengue activity, high passenger traffic, high incidence rates, high epidemic vulnerability, and in geographical proximity to a destination country in Europe. We also found that position of a European country within the air transport network was a strong predictor of the country’s propensity to receive an imported case. Our findings provide evidence that the importation patterns of dengue into Europe can be largely explained by appropriately characterizing the heterogeneities of the source, and topology of the air transport network. This contributes to the foundational framework for building integrated predictive models for bio-surveillance of dengue importation.

Title: Return of the founder Chikungunya virus to its place of introduction into Brazil is revealed by genomic characterization of exanthematic disease cases
Authors: Maia, Zuinara Pereira Gusmão; Pereira, Felicidade Mota; Said, Rodrigo Fabiano do Carmo; Fonseca, Vagner; Gräf, Tiago; Nogueira, Fernanda de Bruycker; Nardy, Vanessa Brandão; Xavier, Joilson; Maia, Maricelia Lima; Abreu, André L.; Albuquerque, Carlos F. Campelo de; Oliveira, Wanderson Kleber; Croda, Julio; Filippis, Ana Maria Bispo de; Cunha, Rivaldo Venancio; Lourenço, Jose; Oliveira, Tulio de; Faria, Nuno Rodrigues; Alcantara, Luiz Carlos Junior; Giovanetti, Marta

Title: Persistence of chikungunya ECSA genotype and local outbreak in an upper medium class neighborhood in Northeast Brazil
Authors: Jesus, Jaqueline Goes de; Wallau, Gabriel da Luz; Maia, Maricelia Lima; Xavier, Joilson; Lima, Maria Aparecida Oliveira; Fonseca, Vagner; Abreu, Alvaro Salgado de; Tosta, Stephane Fraga de Oliveira; Amaral, Helineide Ramos do; Lima, Italo Andrade Barbosa; Silva, Paloma Viana; Santos, Daiana Carlos dos; Oliveira, Aline Sousa de; Souza, Siane Campos de; Falcão, Melissa Barreto; Cerqueira, Erenilde; Machado, Laís Ceschini; Sobral, Mariana Carolina; Rezende, Tatiana Maria Teodoro; Pereira, Mylena Ribeiro; Pereira, Felicidade Mota; Maia, Zuinara Pereira Gusmão; França, Rafael Freitas de Oliveira; Abreu, André Luiz de; Melo, Carlos Frederico Campelo de Albuquerque e; Faria, Nuno Rodrigues; Cunha, Rivaldo Venâncio da; Giovanetti, Marta; Alcantara, Luiz Carlos Junior

Title: Spermathecal Filling in Aedes aegypti and Aedes albopictus: Effects of Female and Male Body Sizes and Species
Authors: Carrasquilla, María C.; Lounibos, Leon Philip; Honorio, Nildimar Alves; Murr, Sarah

Title: Definition of persistent areas with increased dengue risk by detecting clusters in populations with differing mobility and immunity in Rio de Janeiro, Brazil
Authors: Santos, Jefferson Pereira Caldas dos; Honório, Nildimar Alves; Nobre, Aline Araújo
Abstract: A dengue é uma arbovirose reemergente de grande
importância epidemiológica. A detecção de clusters
de dengue representa uma importante estratégia de
vigilância epidemiológica, que contribui para melhor
alocação de medidas de controle no território
e priorização de áreas sujeitas a risco aumentado
de transmissão. São raros os estudos que envolvem
populações humanas com mobilidade baixa;
portanto, este estudo tem como objetivo investigar
a presença de clusters persistentes de dengue no
Município do Rio de Janeiro, Brasil, entre populações
com diferentes padrões de mobilidade e imunidade.
Os dados epidemiológicos sobre dengue
foram obtidos do Ministério da Saúde. As áreas de
risco aumentado foram definidas pelo método estatístico
de varredura espaço-tempo, e a análise de
persistência usou a álgebra cartográfica. Para as
duas populações do estudo, os clusters identificados
não mostraram concordância espacial, exceto
nos anos em que ambas apresentaram o mesmo
perfil imunológico. Para ambas as populações, os
clusters persistentes estavam localizados principalmente
na Zona Oeste da cidade. Os clusters nas
duas populações do estudo mostraram concordância
especial apenas nos anos em que ambas apresentavam
perfis imunológicos semelhantes, o que
confirma o papel de confounding da imunidade
e sustenta o uso de populações com percentuais altos
de indivíduos suscetíveis no desenho de estudos
sobre dengue com base territorial. A semelhança
espaço-temporal entre as áreas de risco persistente
em ambas as populações sugere que a Zona Oeste,
uma região com crescimento urbano desordenado
e média de renda baixa, apresenta o maior risco
de transmissão de dengue. A definição de clusters
de dengue persistentes contribui para o aprimoramento
das estratégias de controle da dengue e de
planejamento territorial.

by Maria Vittoria Mancini, Christie S. Herd, Thomas H. Ant, Shivan M. Murdochy, Steven P. Sinkins

The global incidence of arboviral diseases transmitted by Aedes mosquitoes, including dengue, chikungunya, yellow fever, and Zika, has increased dramatically in recent decades. The release of Aedes aegypti carrying the maternally inherited symbiont Wolbachia as an intervention to control arboviruses is being trialled in several countries. However, these efforts are compromised in many endemic regions due to the co-localization of the secondary vector Aedes albopictus, the Asian tiger mosquito. Ae. albopictus has an expanding global distribution following incursions into a number of new territories. To date, only the wMel and wPip strains of Wolbachia have been reported to be transferred into and characterized in this vector. A Wolbachia strain naturally infecting Drosophila simulans, wAu, was selected for transfer into a Malaysian Ae. albopictus line to create a novel triple-strain infection. The newly generated line showed self-compatibility, moderate fitness cost and complete resistance to Zika and dengue infections.

by Yujiao Zhao, Matthew Amodio, Brent Vander Wyk, Bram Gerritsen, Mahesh M. Kumar, David van Dijk, Kevin Moon, Xiaomei Wang, Anna Malawista, Monique M. Richards, Megan E. Cahill, Anita Desai, Jayasree Sivadasan, Manjunatha M. Venkataswamy, Vasanthapuram Ravi, Erol Fikrig, Priti Kumar, Steven H. Kleinstein, Smita Krishnaswamy, Ruth R. Montgomery

The genus Flavivirus contains many mosquito-borne human pathogens of global epidemiological importance such as dengue virus, West Nile virus, and Zika virus, which has recently emerged at epidemic levels. Infections with these viruses result in divergent clinical outcomes ranging from asymptomatic to fatal. Myriad factors influence infection severity including exposure, immune status and pathogen/host genetics. Furthermore, pre-existing infection may skew immune pathways or divert immune resources. We profiled immune cells from dengue virus-infected individuals by multiparameter mass cytometry (CyTOF) to define functional status. Elevations in IFNβ were noted in acute patients across the majority of cell types and were statistically elevated in 31 of 36 cell subsets. We quantified response to in vitro (re)infection with dengue or Zika viruses and detected a striking pattern of upregulation of responses to Zika infection by innate cell types which was not noted in response to dengue virus. Significance was discovered by statistical analysis as well as a neural network-based clustering approach which identified unusual cell subsets overlooked by conventional manual gating. Of public health importance, patient cells showed significant enrichment of innate cell responses to Zika virus indicating an intact and robust anti-Zika response despite the concurrent dengue infection.

by Yun Wu, Xinyu Yang, Zhicheng Yao, Xinhuai Dong, Danrui Zhang, Yiwen Hu, Shihao Zhang, Jiajie Lin, Jiahui Chen, Shu An, Hengming Ye, Shuqing Zhang, Ziying Qiu, Zhenjian He, Mingxing Huang, Guohong Wei, Xun Zhu

The rapidly emerging human health crisis associated with the Zika virus (ZIKV) epidemic and its link to severe complications highlights the growing need to identify the mechanisms by which ZIKV accesses hosts. Interferon response protects host cells against viral infection, while the cellular factors that mediate this defense are the products of interferon-stimulated genes (ISGs). Although hundreds of ISGs have been identified, only a few have been characterized for their antiviral potential, target specificity and mechanisms of action. In this work, we focused our investigation on the possible antiviral effect of a novel ISG, C19orf66 in response to ZIKV infection and the associated mechanisms. We found that ZIKV infection could induce C19orf66 expression in ZIKV-permissive cells, and such an overexpression of C19orf66 remarkably suppressed ZIKV replication. Conversely, the depletion of C19orf66 led to a significant increase in viral replication. Furthermore, C19orf66 was found to interact and co-localize with ZIKV nonstructural protein 3 (NS3), thus inducing NS3 degradation via a lysosome-dependent pathway. Taken together, this study identified C19orf66 as a novel ISG that exerts antiviral effects against ZIKV by specifically degrading a viral nonstructural protein. These findings uncovered an intriguing mechanism of C19orf66 that targeting NS3 protein of ZIKV, providing clues for understanding the actions of innate immunity, and affording the possible availability of new drug targets that can be used for therapeutic intervention.

by Yoann Teissier, Richard Paul, Maite Aubry, Xavier Rodo, Carlos Dommar, Henrik Salje, Anavaj Sakuntabhai, Bernard Cazelles, Van-Mai Cao-Lormeau

Understanding the transition of epidemic to endemic dengue transmission remains a challenge in regions where serotypes co-circulate and there is extensive human mobility. French Polynesia, an isolated group of 117 islands of which 72 are inhabited, distributed among five geographically separated subdivisions, has recorded mono-serotype epidemics since 1944, with long inter-epidemic periods of circulation. Laboratory confirmed cases have been recorded since 1978, enabling exploration of dengue epidemiology under monotypic conditions in an isolated, spatially structured geographical location. A database was constructed of confirmed dengue cases, geolocated to island for a 35-year period. Statistical analyses of viral establishment, persistence and fade-out as well as synchrony among subdivisions were performed. Seven monotypic and one heterotypic dengue epidemic occurred, followed by low-level viral circulation with a recrudescent epidemic occurring on one occasion. Incidence was asynchronous among the subdivisions. Complete viral die-out occurred on several occasions with invasion of a new serotype. Competitive serotype replacement has been observed previously and seems to be characteristic of the South Pacific. Island population size had a strong impact on the establishment, persistence and fade-out of dengue cases and endemicity was estimated achievable only at a population size in excess of 175 000. Despite island remoteness and low population size, dengue cases were observed somewhere in French Polynesia almost constantly, in part due to the spatial structuration generating asynchrony among subdivisions. Long-term persistence of dengue virus in this group of island populations may be enabled by island hopping, although could equally be explained by a reservoir of sub-clinical infections on the most populated island, Tahiti.

by Megan O’Driscoll, Natsuko Imai, Neil M. Ferguson, Sri Rezeki Hadinegoro, Hindra Irawan Satari, Clarence C. Tam, Ilaria Dorigatti
Background Approximately 70% of the global burden of dengue disease occurs on the Asian continent, where many large urban centres provide optimal environments for sustained endemic transmission and periodic epidemic cycles. Jakarta, the capital of Indonesia, is a densely populated megacity with hyperendemic dengue transmission. Characterization of the spatiotemporal distribution of dengue transmission intensity is of key importance for optimal implementation of novel control and prevention programmes, including vaccination. In this paper we use mathematical models to provide the first detailed description of spatial and temporal variability in dengue transmission intensity in Jakarta. Methodology/Principal findings We applied catalytic models in a Bayesian framework to age-stratified dengue case notification data to estimate dengue force of infection and reporting probabilities in 42 subdistricts of Jakarta. The model was fitted to yearly and average annual data covering a 10-year period between 2008 and 2017. We estimated a long-term average annual transmission intensity of 0.130 (95%CrI: 0.129–0.131) per year in Jakarta province, ranging from 0.090 (95%CrI: 0.077–0.103) to 0.164 (95%CrI: 0.153–0.174) across subdistricts. Annual average transmission intensity in Jakarta province during the 10-year period ranged from 0.012 (95%CrI: 0.011–0.013) in 2017 to 0.124 (95%CrI: 0.121–0.128) in 2016. Conclusions/Significance While the absolute number of dengue case notifications cannot be relied upon as a measure of endemicity, the age-distribution of reported dengue cases provides valuable insights into the underlying nature of transmission. Our estimates from yearly and average annual case notification data represent the first detailed estimates of dengue transmission intensity in Jakarta’s subdistricts. These will be important to consider when assessing the population-level impact and cost-effectiveness of potential control and prevention programmes in Jakarta province, such as the controlled release of Wolbachia-carrying mosquitoes and vaccination.

by Tilly Gurman, Anne Ballard Sara, Florentina Villanueva Lorenzo, Desirée Luis, Gabrielle Hunter, Sean Maloney, Ryanne Fujita-Conrads, Elli Leontsini
Background Zika remains an epidemiological threat in Latin America, including the Dominican Republic. Although transmitted by the same mosquito as Dengue and Chikungunya, Zika is unique in the potentially harmful consequences for babies born to women infected during pregnancy. Experts highlight the feminization of Zika, in terms of burden of disease and women’s caregiving responsibilities. Understanding gender’s role in Zika prevention, therefore, is key to strengthening current and future programs. Methodology/Principal findings This qualitative study, comprised of 12 focus group discussions and eight in-depth interviews, explored gender’s role in Zika among pregnant and non-pregnant women as well as male partners of pregnant women in the Dominican Republic. Topics included perceptions about Zika and perceived feasibility and effectiveness of prevention behaviors (e.g. cleaning water storage containers, using condoms during pregnancy). Researchers applied grounded theory through a process of deductive coding—classifying data around predetermined categories—followed by inductive coding—identifying themes that emerged from coded data. Study findings uncovered three ways in which gender may influence Zika prevention. First, women are largely responsible for household chores—including cleaning water storage containers—with men as assistants. Second, men described their role in the family as the protector. Finally, men and women believed that partners would perceive suggesting condom use or abstinence during pregnancy as a sign of infidelity. Conclusions Current/future Zika programs should address knowledge gaps, especially around water storage cleaning techniques and sexual transmission. Programs should also integrate gender into programming in culturally-relevant ways that avoid reinforcing stereotypes. Furthermore, programs should tailor activities for men, women, as well as the couple. In the end, integrating gender in a way that is mindful of the local context while not exploiting existing gender roles is critical for preventing Zika and similar mosquito-borne diseases, both in the Dominican Republic and throughout the region.

by Elizabeth Fahsbender, Antonio Charlys da-Costa, Danielle Elise Gill, Flavio Augusto de Padua Milagres, Rafael Brustulin, Fred Julio Costa Monteiro, Marlisson Octavio da Silva Rego, Edcelha Soares D’Athaide Ribeiro, Ester Cerdeira Sabino, Eric Delwart

Plasma from patients with dengue-like symptoms was collected in 2013 to 2016 from the Brazilian states of Tocantins and Amapa. 781 samples testing negative for IgM against Dengue, Zika, and Chikungunya viruses and for flaviviruses, alphaviruses and enteroviruses RNA using RT-PCRs were analyzed using viral metagenomics. Viral particles-associated nucleic acids were enriched, randomly amplified, and deep sequenced in 102 mini-pools generating over 2 billion reads. Sequence data was analyzed for the presence of known and novel eukaryotic viral reads. Anelloviruses were detected in 80%, human pegivirus 1 in 19%, and parvovirus B19 in 17% of plasma pools. HIV and enteroviruses were detected in two pools each. Previously uncharacterized viral genomes were also identified, and their presence in single plasma samples confirmed by PCR. Chapparvovirus and ambidensovirus genomes, both in the Parvoviridae family, were partially characterized showing 33% and 34% identity in their NS1 sequences to their closest relative. Molecular surveillance using pre-existing plasma from febrile patients provides a readily scalable approach for the detection of novel, potentially emerging, viruses.

by Bixing Huang, Brian L. Montgomery, Rebecca Adamczyk, Gerhard Ehlers, Andrew F. van den Hurk, David Warrilow
Background Yellow fever, dengue, chikungunya and Zika viruses are responsible for considerable morbidity and mortality in humans. Aedes aegypti and Aedes albopictus are the most important mosquito vectors involved in their transmission. Accurate identification of these species is essential for the implementation of control programs to limit arbovirus transmission, during suspected detections at ports of first entry, to delimit incursions or during presence/absence surveillance programs in regions vulnerable to invasion. We developed and evaluated simple and rapid colorimetric isothermal tests to detect these two mosquito species based on loop-mediated isothermal amplification (LAMP) targeting the ribosomal RNA internal transcribed spacer 1 (ITS1). Methodology/Principal findings Samples were prepared by homogenizing and heating at 99 oC for 10 min before an aliquot was added to the LAMP reaction. After 40 min incubation at 65 oC, a colour change indicated a positive result. The tests were 100% sensitive and species-specific, and demonstrated a limit of detection comparable with PCR-based detection (TaqMan chemistry). The LAMP assays were able to detect target species for various life stages tested (adult, 1st instar larva, 4th instar larva and pupa), and body components, such as legs, wings and pupal exuviae. Importantly, the LAMP assays could detect Ae. aegypti DNA in mosquitoes stored in Biogents Sentinel traps deployed in the field for 14 d. A single 1st instar Ae. aegypti larva could also be detected in a pool of 1,000 non-target 1st instar Aedes notoscriptus, thus expediting processing of ovitrap collections obtained during presence/absence surveys. A simple syringe-sponge protocol facilitated the concentration and collection of larvae from the ovitrap water post-hatch. Conclusions/Significance We describe the development of LAMP assays for species identification and demonstrate their direct application for surveillance in different field contexts. The LAMP assays described herein are useful adjuncts to laboratory diagnostic testing or could be employed as standalone tests. Their speed, ease-of-use, low cost and need for minimal equipment and training make the LAMP assays ideal for adoption in low-resource settings without the need to access diagnostic laboratory services.

by Kerstin D. Rosenberger, Neal Alexander, Eric Martinez, Lucy C. S. Lum, Carl-Erik Dempfle, Thomas Junghanss, Bridget Wills, Thomas Jaenisch, the DENCO Clinical Study Group

Severe dengue was perceived as one clinical disease entity until the WHO 2009 classification stratified it into severe vascular leakage, severe bleeding, and severe organ dysfunction. The objectives of this study were to investigate the potential use of severe dengue categories as endpoints for intervention research. 271 patients with severe dengue among 1734 confirmed dengue patients were followed prospectively in this hospital-based observational study in Latin America and Asia. We compared the distribution of severe dengue categories according to gender and age (below/above 15y), and determined the relative frequency and the overlap of severe dengue categories in the same patients. In a next step, we extended the analysis to candidate moderate severity categories, based on recently suggested definitions which were adapted for our purposes. Severe vascular leakage occurred in 244 (90%), severe bleeding in 39 (14%), and severe organ dysfunction in 28 (10%) of 271 severe dengue patients. A higher frequency of severe leakage was seen in children or adolescents (

by Moses Muia Masika, Essi Korhonen, Teemu Smura, Ruut Uusitalo, Katariina Vapalahti, Dufton Mwaengo, Anne J. Jääskeläinen, Omu Anzala, Olli Vapalahti, Eili Huhtamo

Dengue virus (DENV) has caused recent outbreaks in coastal cities of Kenya, but the epidemiological situation in other areas of Kenya is largely unknown. We investigated the role of DENV infection as a cause of acute febrile disease in non-epidemic settings in rural and urban study areas in Kenya. Altogether, 560 patients were sampled in 2016–2017 in rural Taita–Taveta County (n = 327) and urban slums of Kibera, Nairobi (n = 233). The samples were studied for DENV IgM, IgG, NS1 antigen and flaviviral RNA. IgG seroprevalence was found to be higher in Taita–Taveta (14%) than in Nairobi (3%). Five Taita–Taveta patients were positive for flaviviral RNA, all identified as DENV-2, cosmopolitan genotype. Local transmission in Taita–Taveta was suspected in a patient without travel history. The sequence analysis suggested that DENV-2 strains circulating in coastal and southern Kenya likely arose from a single introduction from India. The molecular clock analyses dated the most recent ancestor to the Kenyan strains a year before the large 2013 outbreak in Mombasa. After this, the virus has been detected in Kilifi in 2014, from our patients in Taita–Taveta in 2016, and in an outbreak in Malindi in 2017. The results highlight that silent transmission occurs between epidemics and also affects rural areas. More information is needed to understand the local epidemiological characteristics and future risks of dengue in Kenya.

by Bangyao Sun, Xin Zhang, Huan Zhang, Haizhou Liu, Lina Sun, Qiqi Tan, Mifang Liang, De Wu, Di Liu

Dengue fever, a mosquito-borne viral disease in humans, has been endemic in many Southeast Asian countries. Since its first outbreak in 1978 in Foshan, Guangdong province, China, dengue has been continually epidemic in recent years in Guangdong, which raised the concern whether dengue infection is endemic in Guangdong. In this study, we performed phylogenetic, recombinant, and nucleotide variation analyses of 114 complete genome sequences of dengue virus serotypes 1–4 (DENV1-4) collected from 2013 to 2017 in 18 of 21 cities of Guangdong. Phylogenetic analyses revealed that DENV sequences did not form a single cluster, indicating that dengue fever was not endemic in Guangdong, although DENV1-4 co-circulated in Guangdong. Twenty intra-serotype recombinant isolates involving DENV1-4 were detected, but no inter-serotype recombinant events were identified in this study. Additionally, the most recombinant events were detected simultaneously in the gene NS3 of DENV1-4. Nucleotide variation analyses showed that no significant intra-serotype differences were observed, whereas more significant inter-subtype differences were discovered in non-structural genes than in structural genes. Our investigation will facilitate the understanding of the current prevalent status of dengue fever in Guangdong and contribute to designing more effective preventive and control strategies for dengue infection.

by Zhiwei Xu, Hilary Bambrick, Francesca D. Frentiu, Gregor Devine, Laith Yakob, Gail Williams, Wenbiao Hu
Background Dengue is a mosquito-borne viral disease and its transmission is closely linked to climate. We aimed to review available information on the projection of dengue in the future under climate change scenarios. Methods Using five databases (PubMed, ProQuest, ScienceDirect, Scopus and Web of Science), a systematic review was conducted to retrieve all articles from database inception to 30th June 2019 which projected the future of dengue under climate change scenarios. In this review, “the future of dengue” refers to disease burden of dengue, epidemic potential of dengue cases, geographical distribution of dengue cases, and population exposed to climatically suitable areas of dengue. Results Sixteen studies fulfilled the inclusion criteria, and five of them projected a global dengue future. Most studies reported an increase in disease burden, a wider spatial distribution of dengue cases or more people exposed to climatically suitable areas of dengue as climate change proceeds. The years 1961–1990 and 2050 were the most commonly used baseline and projection periods, respectively. Multiple climate change scenarios introduced by the Intergovernmental Panel on Climate Change (IPCC), including B1, A1B, and A2, as well as Representative Concentration Pathway 2.6 (RCP2.6), RCP4.5, RCP6.0 and RCP8.5, were most widely employed. Instead of projecting the future number of dengue cases, there is a growing consensus on using “population exposed to climatically suitable areas for dengue” or “epidemic potential of dengue cases” as the outcome variable. Future studies exploring non-climatic drivers which determine the presence/absence of dengue vectors, and identifying the pivotal factors triggering the transmission of dengue in those climatically suitable areas would help yield a more accurate projection for dengue in the future. Conclusions Projecting the future of dengue requires a systematic consideration of assumptions and uncertainties, which will facilitate the development of tailored climate change adaptation strategies to manage dengue.

Title: Práticas educativas para o controle da dengue nos serviços de saúde: o caso do município de Itaboraí
Authors: Sousa, Viviane Alves de
Abstract: A dengue se destaca como um dos maiores problemas de saúde no mundo,
principalmente por possuir uma capacidade de produção de epidemias de vulto nas grandes
cidades com graves implicações econômicas e sociais, sendo de vital interesse para os
setores da saúde pública. O estudo apresentado é uma pesquisa com abordagem qualitativa,
cujo objetivo geral é caracterizar as práticas educativas para o controle da dengue no
município de Itaboraí, relacionando-as com o contexto social onde ocorrem. Os objetivos
específicos são descrever o contexto social e político organizacional onde ocorrem as
práticas de educação e saúde; caracterizar as práticas educativas no Programa de Controle
da Dengue e descrever os limites e possibilidades das práticas para o controle da dengue,
tendo em vista o contexto do município de Itaboraí. Procuram-se salientar os impactos no
município e região com a implantação do Complexo Petroquímico do Rio de Janeiro
(COMPERJ) no ano de 2006. Para descrição do contexto social e político organizacional,
enfatizando-se a governabilidade, e para caracterização das práticas e descrição dos limites
e possibilidades foram utilizadas a análise documental e entrevistas semiestruturadas com
roteiros previamente elaborados. Foram entrevistados cinco profissionais que atuam no
nível central e no nível local. Os resultados do estudo mostraram mudanças frequentes de
gestores no setor de saúde do município. Essa instabilidade parece coincidir temporalmente
com a instalação do Comperj. Os serviços de educação em saúde parecem se ressentir da
desativação do Núcleo de Educação em Saúde (NES). O Núcleo é mencionado, mas não
mais aparece no organograma da Secretaria Municipal de Saúde. A fala dos sujeitos
entrevistados revelou uma interrupção das ações educativas e falta de regularidade na
capacitação para esses serviços. Não há regularidade de planejamento e avaliação das
atividades. Os discursos dos entrevistados revelaram que a visão sobre as ações de
educação em saúde é predominantemente modelada segundo as abordagens tradicionais,
verticais e prescritivas. Observa-se uma contradição em alguns discursos, quando ressaltam
a necessidade de atenção em relação à escuta e à consideração do contexto local de vida e
das possibilidades de participação popular no processo educativo, mas observam que a
população não cumpre o que lhes é determinado.

Title: Neurodevelopment of children exposed intra-uterus by Zika virus: A case series
Authors: Peçanha, Pedro Massaroni; Gomes Junior, Saint Clair; Pone, Sheila Moura; Pone, Marcos Vinicius da Silva; Vasconcelos, Zilton; Zin, Andrea; Vilibor, Renata Hydee Hasue; Costa, Roozemeria Pereira; Meio, Maria Dalva Barbosa Baker; Nielsen-Saines, Karin; Brasil, Patricia; Brickley, Elizabeth; Lopes Moreira, Maria Elisabeth

by Clare Wenham, João Nunes, Gustavo Correa Matta, Carolina de Oliveira Nogueira, Polyana Aparecida Valente, Denise Nacif Pimenta

by Preston K. Manwill, Megha Kalsi, Sijin Wu, Erick J. Martinez-Rodriguez, Xiaolin Cheng, Peter M. Piermarini, Harinantenaina L. Rakotondraibe

The Aedes aegypti mosquito serves as a major vector for viral diseases, such as dengue, chikungunya, and Zika, which are spreading across the globe and threatening public health. In addition to increased vector transmission, the prevalence of insecticide-resistant mosquitoes is also on the rise, thus solidifying the need for new, safe and effective insecticides to control mosquito populations. We recently discovered that cinnamodial, a unique drimane sesquiterpene dialdehyde of the Malagasy medicinal plant Cinnamosma fragrans, exhibited significant larval and adult toxicity to Ae. aegypti and was more efficacious than DEET–the gold standard for insect repellents–at repelling adult female Ae. aegypti from blood feeding. In this study several semi-synthetic analogues of cinnamodial were prepared to probe the structure-activity relationship (SAR) for larvicidal, adulticidal and antifeedant activity against Ae. aegypti. Initial efforts were focused on modification of the dialdehyde functionality to produce more stable active analogues and to understand the importance of the 1,4-dialdehyde and the α,ß-unsaturated carbonyl in the observed bioactivity of cinnamodial against mosquitoes. This study represents the first investigation into the SAR of cinnamodial as an insecticide and antifeedant against the medically important Ae. aegypti mosquito.

by Joseph R. McMillan, Philip M. Armstrong, Theodore G. Andreadis
Background In the northeast United States (U.S.), mosquitoes transmit a number of arboviruses, including eastern equine encephalitis, Jamestown Canyon, and West Nile that pose an annual threat to human and animal health. Local transmission of each arbovirus may be driven by the involvement of multiple mosquito species; however, the specificity of these vector-virus associations has not been fully quantified. Methodology We used long-term surveillance data consistently collected over 18 years to evaluate mosquito and arbovirus community composition in the State of Connecticut (CT) based on land cover classifications and mosquito species-specific natural histories using community ecology approaches available in the R package VEGAN. We then used binomial-error generalized linear mixed effects models to quantify species-specific trends in arbovirus detections. Primary results The composition of mosquito communities throughout CT varied more among sites than among years, with variation in mosquito community composition among sites explained mostly by a forested-to-developed-land-cover gradient. Arboviral communities varied equally among sites and years, and only developed and forested wetland land cover classifications were associated with the composition of arbovirus detections among sites. Overall, the avian host arboviruses, mainly West Nile and eastern equine encephalitis, displayed the most specific associations among mosquito species and sites, while in contrast, the mammalian host arboviruses (including Cache Valley, Jamestown Canyon, and Potosi) associated with a more diverse mix of mosquito species and were widely distributed throughout CT. Conclusions We find that avian arboviruses act as vector specialists infecting a few key mosquito species that associate with discrete habitats, while mammalian arboviruses are largely vector generalists infecting a wide diversity of mosquito species and habitats in the region. These distinctions have important implications for the design and implementation of mosquito and arbovirus surveillance programs as well as mosquito control efforts.

by Saeed Anwar, Jarin Taslem Mourosi, Md. Fahim Khan, Mohammad Ohid Ullah, Olivier M. Vanakker, Mohammad Jakir Hosen
Introduction A massive outbreak of chikungunya virus (CHIKV) occurred in Bangladesh during the period of April-September 2017, and over two million people were at risk of getting infected by the virus. A prospective cohort of viremic patients was constituted and analyzed to define the clinical, hematological, and long-term aspects of this outbreak. Methods A 35-day long comprehensive survey was conducted in two major, neighboring cities, Dhaka and Mymensingh. One-hundred and eighty-seven laboratory-confirmed CHIKV cases were enrolled in the cross-sectional cohort study. Additionally, a smaller group of 48 chikungunya patients was monitored for post-infection effects for 12 months. Results Clinical data revealed that a combination of fever and arthralgia (oligoarthralgia and/or polyarthralgia) was the cardinal hallmark (97.9% of cases) of the infection. Hematological analysis showed that irrespective of age and sex groups, CHIKV patients had a decreased level of hemoglobin (n = 64, p 0.01) and elevated erythrocyte sedimentation rate (n = 131, p 0.01). Besides, a significant portion of the patients represented abnormal values for RBC (n = 38, p = 0.0005) and WBC (n = 63, p 0.01) counts. The post-infection study revealed that children had an early recovery from the infection compared to the adults. Moreover, post-infection weakness, successive relapse of arthralgic pain, and memory problems were the most significant aftereffects, which had an impact on the daily activities of patients. Conclusions This study represents a comprehensive overview of clinical and epidemiological features of the 2017 outbreak of CHIKV in Bangladesh as well as its chronic outcomes till the 12th month. It provides insights into the natural history of this disease, which may help to improve the management of CHIKV patients.

Title: Participação social no controle da dengue: a importância de uma mudança conceitual
Authors: Jardim, João Bosco; Schall, Virgínia Torres
Description: Palavras-chave inseridas após a leitura do capítulo.