The role of NSP6 in the biogenesis of the SARS-CoV-2 replication organelle

SARS-CoV-2, like other coronaviruses, builds a membrane-bound replication organelle (RO) to enable RNA replication1. The SARS-CoV-2 RO is composed of double membrane vesicles (DMVs) tethered to the endoplasmic reticulum (ER) by thin membrane connectors2, but the viral proteins and the host factors involved are currently unknown. Here we identify the viral non-structural proteins (NSPs) that generate the SARS-CoV-2 RO. NSP3 and NSP4 generate the DMVs while NSP6, through oligomerization and an amphipathic helix, zippers ER membranes and establishes the connectors. The NSP6ΔSGF mutant, which arose independently in the α, β, γ, η, ι, and λ variants of SARS-CoV-2, behaves as a gain-of-function mutant with a higher ER-zippering activity. We identified three main roles for NSP6: to act as a filter in RO-ER communication allowing lipid flow but restricting access of ER luminal proteins to the DMVs, to position and organize DMV clusters, and to mediate contact with lipid droplets (LDs) via the LD-tethering complex DFCP1-Rab18. NSP6 thus acts as an organizer of DMV clusters and can provide a selective track to refurbish them with LD-derived lipids. Importantly, both properly formed NSP6 connectors and LDs are required for SARS-CoV-2 replication. Our findings, uncovering the biological activity of NSP6 of SARS-CoV-2 and of other coronaviruses, have the potential to fuel the search for broad antiviral agents.

Field validation of the performance of paper-based tests for the detection of the Zika and chikungunya viruses in serum samples

In low-resource settings, resilience to infectious disease outbreaks can be hindered by limited access to diagnostic tests. Here we report the results of double-blinded studies of the performance of paper-based diagnostic tests for the Zika and chikungunya viruses in a field setting in Latin America. The tests involved a cell-free expression system relying on isothermal amplification and toehold-switch reactions, a purpose-built portable reader and onboard software for computer vision-enabled image analysis. In patients suspected of infection, the accuracies and sensitivities of the tests for the Zika and chikungunya viruses were, respectively, 98.5% (95% confidence interval, 96.2–99.6%, 268 serum samples) and 98.5% (95% confidence interval, 91.7–100%, 65 serum samples) and approximately 2 aM and 5 fM (both concentrations are within clinically relevant ranges). The analytical specificities and sensitivities of the tests for cultured samples of the viruses were equivalent to those of the real-time quantitative PCR. Cell-free synthetic biology tools and companion hardware can provide de-centralized, high-capacity and low-cost diagnostics for use in low-resource settings.

Ecologic Determinants of West Nile Virus Seroprevalence among Equids, Brazil

Você conhece os impactos do vírus Zika sobre as famílias?

*Portuguese content* Com objetivo de avaliar como as famílias dessas crianças foram impactadas, a pesquisa Impactos econômicos e sociais do vírus Zika foi realizada no IFF-Fiocruz, hospital público federal situado no Rio de Janeiro, que atua em ensino, pesquisa e atendimento a mulheres, crianças e adolescentes.

Pregnant Women Infected with Zika Virus Show Higher Viral Load and Immunoregulatory Cytokines Profile with CXCL10 Increase

Results in this paper reveal that the anti-inflammatory response in pregnant women infected with ZIKA is characterized by high CXCL10, a cytokine correlated with congenital malformations.

Zika virus infection in pregnancy: a protocol for the joint analysis of the prospective cohort studies of the ZIKAlliance, ZikaPLAN and ZIKAction consortia

This article provides a protocol for the joint analysis of the prospective cohort studies of the ZIKAlliance, ZikaPLAN and ZIKAction consortia.

Zika virus transmission by Brazilian Aedes aegypti and Aedes albopictus is virus dose and temperature-dependent

Results indicate that Brazilian populations of Ae. aegypti exhibit a much higher transmission potential for ZIKV than Ae. albopictus.

Contrasted transmission efficiency of Zika virus strains by mosquito species Aedes aegypti, Aedes albopictus and Culex quinquefasciatus from Reunion Island

Our results show that both Ae. albopictus and Ae. aegypti, from Reunion Island, are more likely to be competent for ZIKV in contrast to Cx. quinquefasciatus which appeared refractory to all tested ZIKV strains. This improves our understanding of the role of mosquito species in the risk of the ZIKV emergence on Reunion Island.

Vector Competence of Aedes aegypti, Aedes albopictus and Culex quinquefasciatus from Brazil and New Caledonia for Three Zika Virus Lineages

Viral surveillance and mosquito control measures must be strengthened to avoid the spread of new ZIKV lineages and minimize the transmission of viruses currently circulating.

Detection of arboviruses in mosquitoes: Evidence of circulation of chikungunya virus in Iran

This is the first report of mosquitoes infected with CHIKV in Iran. The high-throughput screening method here presented can be proposed as a novel epidemiological surveillance tool to identify circulating arboviruses and to support preparedness to an epidemic in animals and humans.

Forced Zika Virus Infection of Culex pipiens Leads to Limited Virus Accumulation in Mosquito Saliva

In this study, researchers provide the first demonstration of ZIKV accumulation in the saliva of Cx. pipiens upon forced infection. Nevertheless, they consider Cx. pipiens as a highly inefficient vector for ZIKV.

Rapid decline of Zika virus NS1 antigen-specific antibody responses, northeastern Brazil

Researchers have found that ZIKV immunity might be shorter-lived than previously thought, which may contribute to local ZIKV resurgence once individual immune responses wane sufficiently to reduce community protective immunity in addition to birth and migration.

Reconstructing Mayaro virus circulation in French Guiana shows frequent spillovers

These findings highlight the need to strengthen MAYV surveillance in the region and showcase how modeling can improve interpretation of cross-reacting assays.

Zika Virus Circulation in Mali

This study demonstrates the circulation of ZIKV in Mali and provides evidence of a previously unidentified outbreak that occurred in the late 1990s.

The invasive Asian bush mosquito Aedes japonicus found in the Netherlands can experimentally transmit Zika virus and Usutu virus

Given that Ae. japonicus can experimentally transmit arthropod-borne viruses (arboviruses) like ZIKV and USUV and is currently expanding its territories, we should consider this mosquito as a potential vector for arboviral diseases in Europe.

A Systematic Review: Is Aedes albopictus an Efficient Bridge Vector for Zoonotic Arboviruses?

This analysis confirms the potential of Ae. albopictus as a bridge vector based on its colonization of natural breeding sites in newly invaded areas, its opportunistic feeding behaviour together with the preference for human blood, and the competence to transmit 14 arboviruses.

Survey on Non-Human Primates & Mosquitoes Does not Provide Evidences of Spillover/Spillback between the Urban & Sylvatic Cycles of YFV & ZIKV Following Severe Outbreaks in Southeast Brazil

The present study showed that there is no evidence that the ZIKV established an independent sylvatic cycle in the state of Rio de Janeiro, and provided new evidence that there was no urban transmission of Yellow Fever Virus in southeast Brazil during the current outbreak.

The global scientific research response to the public health emergency of Zika virus infection

Mapping the response to Zika, a public health emergency, demonstrated a clear pattern of the participation of countries in the scientific advances. The pattern of knowledge production found in this study represented varying country perspectives, research capacity and interests based first on their level of exposure to the epidemic and second on their financial positions regarding science.

Gender mainstreaming as a pathway for sustainable arbovirus control in Latin America

Building on the UN’s Sustainable Development Goals commitment to “leave no one behind” and the recent championing of a need for a people-centered approach to epidemic preparedness and response, the authors call for more evidence that can support policy recommendations and advocacy efforts for gender-mainstreamed arbovirus control programs in Latin America.

Genomic and Epidemiological Surveillance of Zika Virus in the Amazon Region

This study reveals how the ZIKV epidemic was ignited and maintained within the largest urban metropolis in the Amazon. These results might contribute to improving the public health response to outbreaks in Brazil.

From ancient to emerging infections: the odyssey of viruses in the male genital tract

The authors review here how viruses, from ancient viruses that integrated the germ line during evolution through old viruses (e.g. papillomaviruses originating from Neanderthals) and more modern sexually-transmitted infections (e.g. simian zoonotic HIV) to emerging viruses (e.g. Ebola and Zika) take advantage of genital tract colonization for horizontal dissemination, viral persistence, vertical transmission and endogenization.

Robustness of Serologic Investigations for Chikungunya and Mayaro Viruses following Coemergence

In this study the authors' data provide a convenient and practicable solution to ensure robust differentiation of CHIKV- and MAYV-specific antibodies.

A new class of broadly neutralizing antibodies that target the glycan loop of Zika virus envelope protein

Results showed in this article have strong implications for developing anti-ZIKV vaccines and therapeutic mAbs.

Identification of animal hosts of Fort Sherman virus, a New World zoonotic orthobunyavirus

Findings in this study highlight the occurrence of the Fort Sherman virus (FSV) across a geographic range exceeding 7,000 km, surprising genomic conservation across a time span exceeding 50 years, M gene‐based reassortment events, and the existence of multiple animal hosts of FSV.

Recombination of B- and T-cell epitope-rich loci from Aedes- and Culex-borne flaviviruses shapes Zika virus epidemiology

Findings from this article explain why explosive ZIKV epidemics occurred in DENV-endemic regions of Micronesia, Polynesia and the Americas where Culex-borne flavivirus outbreaks are infrequent, and why ZIKV did not cause major epidemics in Asia where Culex-borne flaviviruses are widespread.

Zika seroprevalence declines and neutralizing antibodies wane in adults following outbreaks in French Polynesia and Fiji

Data from this study suggest that immunity against the Zika virus may not last as long as previously thought, which could affect the chances of future outbreaks.

Spatiotemporal Analysis of the Population Risk of Congenital Microcephaly in Pernambuco State, Brazil

This study emphasizes the burden of microcephaly during the outbreak in Pernambuco, with estimates higher than in some previous studies, and with high risk in an inland region of the state for reasons which are yet to be clarified.

Viral emergence and immune interplay in flavivirus vaccines

Comment

Study protocol for the multicentre cohorts of Zika virus infection in pregnant women, infants, and acute clinical cases in Latin America and the Caribbean: the ZIKAlliance consortium

Results of large cohort studies will provide better risk estimates for birth defects and other developmental abnormalities associated with ZIKV infection including possible co-factors for the variability of risk estimates between other countries and regions. Additional outcomes include incidence and transmission estimates of ZIKV during and after pregnancy, characterization of short and long-term clinical course following infection and viral kinetics of ZIKV.

Estimating the risk of arbovirus transmission in Southern Europe using vector competence data

Based on vector competence data and vector distribution, the auhtors generate a prediction risk map for CHIKV stressing the fear of CHIKV and to a lesser extent, of other arboviruses for Europe, calling us for new public health strategies.

Typical epidemiology of respiratory virus infections in a Brazilian slum

For this study researchers collected nasopharyngeal specimens from 282 children aged ≤5 years with acute respiratory tract infection (ARI) during 2005 to 2006 in one of the largest Brazilian slums.

Zika virus threshold determines transmission by European Aedes albopictus mosquitoes

Results in this study stress the poor ability of Ae. albopictus to sustain a local transmission of ZIKV in Europe and provide a promising tool to evaluate the risk of ZIKV transmission in future outbreaks.

Zika Virus Outbreak on Curaçao and Bonaire, a Report Based on Laboratory Diagnostics Data

ZIKV cases confirmed by qRT-PCR indicate that the virus was circulating on Curaçao between at least December 2015 and March 2017, and on Bonaire between at least October 2016 and February 2017, with peak cases occurring in November 2016.

Management of insecticide resistance in the major Aedes vectors of arboviruses: Advances and challenges

Based on a plan developed for malaria vectors, here the authors propose some key activities to establish a global plan for insecticide resistance management in Aedes species.

Yeast-produced subunit protein vaccine elicits broadly neutralizing antibodies that protect mice against Zika virus lethal infection

Yeast-derived EDIII is a safe and effective ZIKV vaccine candidate with desirable production traits.

A New High-Throughput Tool to Screen Mosquito-Borne Viruses in Zika Virus Endemic/Epidemic Areas

The authors present and show a new tool that can detect endemic and epidemic viruses in different mosquito species in an epidemic context. This fast and low-cost method can be suggested as a novel epidemiological surveillance tool to identify circulating arboviruses.

High specificity and sensitivity of Zika EDIII-based ELISA diagnosis highlighted by a large human reference panel

Researchers developed a ZEDIII-based ELISA that can discriminate between past or current DENV and ZIKV infections, allowing the detection of a serological scar from other flaviviruses. This could be used to confirm exposure of pregnant women or to follow the spread of an endemic disease.

Complex Scenario of Homotypic and Heterotypic Zika Virus Immune Enhancement

Letter to the Editor

Sloths host Anhanga virus‐related phleboviruses across large distances in time and space

In this study, researchers confirmed the association of Anhanga virus (ANHV)‐related viruses with both extant two‐toed sloth species in the Choloepus genus across 3,000 km distance and half a century between the both detections.

Impact of Zika Virus Emergence in French Guiana: A Large General Population Seroprevalence Survey

This study described a large-scale representative ZIKV seroprevalence study in South America from the recent 2015–2016 Zika epidemic. The findings reveal that the majority of the population remains susceptible to ZIKV, which could potentially allow future reintroductions of the virus.

Experimental Assessment of Zika Virus Mechanical Transmission by Aedes aegypti

In this study, researchers evaluated the propensity of Aedes aegypti to transmit mechanically Zika virus (ZIKV) using an experimental design.

Zika virus differentially infects human neural progenitor cells according to their state of differentiation and dysregulates neurogenesis through the Notch pathway

Results from this research show that the differentiation state of hNPCs is a significant factor contributing to the outcome of ZIKV infection and furthermore suggest that ZIKV infection might initiate early activation of the Notch pathway resulting in an abnormal differentiation process, implicated in ZIKV-induced brain injury.

Enhanced Molecular Surveillance of Chikungunya Virus

The authors of this study developed two highly sensitive nested RT-PCR assays that cover hot spots of vector adaptation in CHIKV envelope domains. The new assays allow unprecedented molecular surveillance across all CHIKV genotypes and diagnostic use in resource-limited settings globally.

Whole-Blood Testing for Diagnosis of Acute Zika Virus Infections in Routine Diagnostic Setting

Comparison of Zika virus quantitative reverse transcription PCR results in single timepoint whole blood–plasma pairs from 227 patients with suspected Zika virus infection resulted in confirmation of 8 additional patients with Zika virus infection.

Assessing the Potential Interactions between Cellular miRNA and Arboviral Genomic RNA in the Yellow Fever Mosquito, Aedes aegypti

This study shows a broad picture of possible interactions between mosquito cellular miRNAs and the viral RNA of different genotypes/lineages of arboviruses, providing a list of mosquito cellular miRNAs candidates for experimental validations in future studies.

Zika virus infection: an update

Since the ZIKV outbreak in Brazil in 2015, the scientific community has joined efforts to gather more information on the epidemiology, clinical features and pathogenicity of the virus. Here, you can read a summary of the most important advances made recently and the discussion of promising, innovative approaches to understand and control ZIKV infection.

Transmission potential of African, Asian and American Zika virus strains by Aedes aegypti and Culex quinquefasciatus from Guadeloupe (French West Indies)

Culex quinquefasciatus mosquitoes from Guadeloupe are not able to experimentally transmit ZIKV. It was also noticed better transmission of ZIKV strain from Senegal by Ae. aegypti from Guadeloupe compared to Malaysia and Martinique strains.

A computational method for the identification of Dengue, Zika and Chikungunya virus species and genotypes

In this study, the authors developed an efficient method to classify virus sequences with respect to their species and sub-species (i.e. serotype and/or genotype).

Past and future spread of the arbovirus vectors Aedes aegypti and Aedes albopictus

This study offers an opportunity to strategically target surveillance and control programmes and thereby augment efforts to reduce arbovirus burden in human populations globally.

A Viral Polymerase Inhibitor Reduces Zika Virus Replication in the Reproductive Organs of Male Mice

In this study, the authors explore the potential of antivirals to serve as an effective strategy to prevent sexual transmission. The data illustrate the value of a mouse model to validate the efficacy of new potential ZIKV drugs at the level of the male reproductive system.

Zika Virus Infection Induces Elevation of Tissue Factor Production and Apoptosis on Human Umbilical Vein Endothelial Cells

In this study, the authors provide in vitro evidence that infection of HUVECs with ZIKV induces apoptosis and elevation of TF expression that leads to activation of secondary hemostasis.

The possible role of cross-reactive dengue virus antibodies in Zika virus pathogenesis

In this review, the authors summarize the results of the evidence to date and elaborate on other possible detrimental effects of cross-reactive flavivirus antibodies, both for ZIKV infection and the risk of ZIKV-related congenital anomalies, DENV infection, and dengue hemorrhagic fever.

Assessing Zika Virus Transmission Within Households During an Outbreak in Martinique, 2015–2016

This study characterized the contribution of household transmission in ZIKV epidemics, demonstrating the benefits of integrating multiple data sets to gain more insight into epidemic dynamics.

The Human Upper Respiratory Tract Epithelium Is Susceptible to Flaviviruses

Data in this study suggest that the human upper respiratory tract epithelium is a target for flaviviruses and could potentially play a role in the spread of infection to other body compartments through basolateral virus release. Further work is required to evaluate the risks and define the adapted measures to protect individuals exposed to flavivirus-contaminated body fluids.

Lipidomic Analysis Reveals Serum Alteration of Plasmalogens in Patients Infected With ZIKA Virus

Data provided in this article add important insights into specific host cellular lipids that are likely associated with ZIKV replication and may serve as platform for antiviral strategy against ZIKV.

Zika virus infection among symptomatic patients from two healthcare centers in Sao Paulo State, Brazil: prevalence, clinical characteristics, viral detection in body fluids and serodynamics

This study shows that urine ZIKV RT-PCR testing in the acute phase of infection can improve the sensitivity of diagnosis, while testing serum is probably less useful despite more sustained shedding in some cases. Higher sensitivity and specificity serological tests are needed for the diagnosis of patients who seek medical attention after the period of ZIKV detection by RT-PCR and for surveillance purposes in settings of high DENV background infection.

Scientific collaboration in Zika: identification of the leading research groups and researchers via social network analysis

This study shows that a Zika researcher’s influence is basically determined by three factors: (a) number of publications; (b) diversified partnerships; and (c) the links established with the research area’s pioneers.

SAMHD1 Enhances Chikungunya and Zika Virus Replication in Human Skin Fibroblasts

In this study, the authors determined the global proteomic profile of CHIKV and ZIKV infections in human skin fibroblasts using Stable Isotope Labelling by Amino acids in Cell culture (SILAC)-based mass-spectrometry analysis.

The Unfolded Protein Response: A Key Player in Zika Virus-Associated Congenital Microcephaly

The discovery of the link between ZIKV infection and UPR activation has a broader relevance, since this pathway plays a crucial role in many distinct cellular processes and its induction by ZIKV may account for several reported ZIKV-associated defects.

Genomic, epidemiological and digital surveillance of Chikungunya virus in the Brazilian Amazon

This study highlights the potential of combining traditional surveillance with portable genome sequencing technologies and digital epidemiology to inform public health surveillance in the Amazon region. Data reveal a large CHIKV-ECSA outbreak in Boa Vista, limited potential for future CHIKV outbreaks, and indicate a replacement of the Asian genotype by the ECSA genotype in the Amazon region.

Low Zika Virus Seroprevalence in Vientiane, Laos, 2003–2015

With a low herd immunity in the Vientiane population, ZIKV represents a risk for future large-scale outbreaks. Implementation of a nationwide ZIKV surveillance network and epidemiological studies throughout Laos is needed.

The association between Zika virus infection and microcephaly in Brazil 2015–2017: An observational analysis of over 4 million births

This study strengthens the evidence that congenital ZIKV infection, particularly in the first 2 trimesters of pregnancy, is associated with microcephaly and less frequently with other birth defects. The finding of no alternative causes for geographic differences in microcephaly rate lead the authors to hypothesize that the Northeast region of Brazil was disproportionately affected by this Zika outbreak, with 94% of an estimated 8.5 million total cases occurring in this region, suggesting a need for seroprevalence surveys to determine the underlying reason.

The difficulties in obtaining reliable Zika virus diagnostics

Correspondence re: Familiar barriers still unresolved - a perspective on the Zika virus outbreak research response

Potential of Aedes albopictus to cause the emergence of arboviruses in Morocco

Results obtained in this study suggest that the local transmission of four arboviruses - dengue (DENV), chikungunya (CHIKV), zika (ZIKV) and yellow fever (YFV) viruses - by Ae. albopictus newly introduced in Morocco is a likely scenario.

Zika Virus Seroprevalence in Urban and Rural Areas of Suriname, 2017

In Suriname, 770 participants were recruited from 1 urban area and 2 rural villages in the tropical rainforest in order to conduct a ZIKV serosurvey. Researchers found that 35.1% of the participants had neutralizing antibodies against ZIKV. In 1 remote village in the rainforest, 24.5% of the participants had neutralizing antibodies against ZIKV, suggesting that ZIKV was widely spread across the country.

Control of Acute Arboviral Infection by Natural Killer Cells

In this study, researchers review recent developments in the understanding of the immune response, with an emphasis on the early antiviral immune response mediated by natural killer cells and emphasize their Janus-faced effects in the control of arbovirus infection and pathogenesis.

Monocyte-Derived Dendritic Cells as Model to Evaluate Species Tropism of Mosquito-Borne Flaviviruses

The authors of this study demonstrate Flavivirus-dependent differences in the interaction with monocyte-derived dendritic cells. These may play a role in pathogenesis but appear to only partially reflect the expected species tropism.

Differential Shedding and Antibody Kinetics of Zika and Chikungunya Viruses, Brazil

Recurrent recent arbovirus infections suggested by serologic data and unspecific symptoms highlight the need for exhaustive virologic testing.

Optimization of a fragment linking hit toward Dengue and Zika virus NS5 methyltransferases inhibitors

A fragment-based drug design approach on flavivirus methyltransferase.

Combination of ELISA screening and seroneutralisation tests to expedite Zika virus seroprevalence studies

The authors of this study propose a strategy allowing implementing efficient and practicable large-scale seroepidemiological studies for Zika Virus (ZIKV).

Human stem cell-derived hepatocyte-like cells support Zika virus replication and provide a relevant model to assess the efficacy of potential antivirals

The authors of this study demonstrate that both human pluripotent stem cell (hPSC)-derived hepatocyte-like cells (HLCs) and the Huh7 hepatoma cell line support the complete ZIKV replication cycle.

Neurodevelopment in Infants Exposed to Zika Virus In Utero

Letter to the Editor

A yellow fever–Zika chimeric virus vaccine candidate protects against Zika infection and congenital malformations in mice

The authors of this study report the engineering of a chimeric virus vaccine candidate (YF-ZIKprM/E) by replacing the antigenic surface glycoproteins and the capsid anchor of YFV-17D with those of a prototypic Asian lineage ZIKV isolate.

Novel broad spectrum virucidal molecules against enveloped viruses

Researchers report on a class of rhodanine and thiobarbituric derivatives displaying a broad spectrum antiviral activity against seven different enveloped viruses including an HSV-2 acyclovir resistant strain with favorable selectivity indexes.

Potential of Aedes albopictus as a bridge vector for enzootic pathogens at the urban-forest interface in Brazil

Results from this study show that Ae. albopictus frequency declines as it penetrates into the forest and highlight its potential role as a bridge vector of zoonotic diseases at the edge of the Brazilian forests studied.

Favipiravir inhibits in vitro Usutu virus replication and delays disease progression in an infection model in mice

This study shows that treatment of mice with favipiravir (150 mg/kg/dose, BID, oral gavage) significantly reduced viral load in blood and tissues and significantly delayed virus-induced disease. The USUV mouse model is amenable for assessing the potential in vivo efficacy of (novel) USUV/flavivirus inhibitors.

Familiar barriers still unresolved - a perspective on the Zika virus outbreak research response

The authors of this study have identified three major bottlenecks in the implementation of a swift response to the increasing frequency of widespread infectious disease outbreaks: the absence of a timeline for the funding process, delays in regulatory and ethical approval, and the challenging logistics of laboratory support, including diagnostics.

Research Models and Tools for the Identification of Antivirals and Therapeutics against Zika Virus Infection

This review focuses on the recent advances regarding research models, as well as available experimental tools that can be used for the identification and characterization of potential antiviral targets and therapeutic intervention strategies.

Potential effect of Zika virus infection on human male fertility?

The findings from this study suggest a possible long-term detrimental effect of ZIKV infection on human male fertility that has to be further explored in well-characterized samples from cohort studies conducted in ZIKV-endemic areas.

Zika virus infection modulates the metabolomic profile of microglial cells

In the present study, the authors investigate the metabolomic profile of ZIKV-infected microglia.

Projecting the end of the Zika virus epidemic in Latin America: a modelling analysis

The findings in this article suggest that the ZIKV epidemic is by and large over within LAC, with incidence projected to be low in most cities in 2018. Local low levels of transmission are probable, but the estimated rate of infection suggests that most cities have a population with high levels of herd immunity.

Zika virus infects human testicular tissue and germ cells

This study provides key insights into how ZIKV may persist in semen and alter semen parameters, as well as a valuable tool for testing antiviral agents.

Differential transmission of Asian and African Zika virus lineages by Aedes aegypti from New Caledonia

The results of this study demonstrate that Ae. aegypti from New Caledonia can become infected and replicate different ZIKV strains belonging to all lineages. These data emphasize the importance of studying the interaction between vectors and their arboviruses according to each local geographic context.

Lessons learnt from the emergence of Zika virus

Comment

Exhaustive TORCH Pathogen Diagnostics Corroborate Zika Virus Etiology of Congenital Malformations in Northeastern Brazil

Data from this study support a link between maternal ZIKV infection and congenital malformations and suggest the occurrence of predominantly vector-borne ZIKV transmission in these cases. In addition, some highly prevalent TORCH pathogens may be misinterpreted as representative of ongoing ZIKV activity in the absence of exhaustive diagnostics in northeastern Brazil.

Zika virus outbreak in the Pacific: Vector competence of regional vectors

Results from this study indicate a low ZIKV transmission by Ae. aegypti and Ae. polynesiensis tested from the Pacific region. These results were unexpected and suggest the importance of other factors especially the vector density, the mosquito lifespan or the large immunologically naive fraction of the population that may have contributed to the rapid spread of the ZIKV in the Pacific region during the 2013–2017 outbreak.

A Novel Marsupial Hepatitis A Virus Corroborates Complex Evolutionary Patterns Shaping the Genus Hepatovirus

The authors conducted field work in Brazil to sample marsupials, one of the most ancient mammalian lineages, and identified a new HAV, marsupial HAV (MHAV).

External Quality Assessment for Zika Virus Molecular Diagnostic Testing, Brazil

The results from this study emphasize the need for continuous quality assessments of Zika virus diagnostic testing globally.

Zika virus and Guillain–Barré syndrome in Bangladesh

Researchers found no significant association between ZIKV infection and GBS in Bangladesh, but GBS following ZIKV infection was characterized by a distinct clinical and electrophysiological subtype compared to C. jejuni infection. These findings indicate that ZIKV may precede a specific GBS subtype but the risk is low.

Pregnancy Outcomes after ZIKV Infection in French Territories in the Americas

The risk of congenital neurologic defects related to Zika virus (ZIKV) infection has ranged from 6 to 42% in various reports. The aim of this study was to estimate this risk among pregnant women with symptomatic ZIKV infection in French territories in the Americas.

Zika virus epidemiology in Bolivia: A seroprevalence study in volunteer blood donors

The authors conclude that ZIKV has been circulating in Bolivian tropical areas but not in highlands, and that the epidemic has not been limited by previous immunity against dengue. Specific attention should be paid to the region of Santa Cruz, where the seroprevalence is still limited, but the density of Aedes aegypti populations makes plausible further spreading of the disease.

An overview of mosquito vectors of Zika virus

According to the authors of this study, mosquito control measures should remain focused on the mosquito Ae. aegypti which is also the vector of CHIKV and DENV, and much more research effort should be allocated to fill the knowledge gaps about this virus.

A novel hepatitis B virus species discovered in capuchin monkeys sheds new light on the evolution of primate hepadnaviruses

Data in this article suggest ancestral co-speciation of hepadnaviruses and NHP, and an Old World origin of the divergent HBV genotypes F/H. The identification of a novel primate hepadnavirus offers new perspectives for urgently needed animal models of chronic hepatitis B.

Evidence for multiple sylvatic transmission cycles during the 2016–2017 yellow fever virus outbreak, Brazil

Since December 2016, Brazil has experienced an unusually large outbreak of yellow fever (YF). Whether urb a n transmission may contribute to the extent of the outbreak is unclear. The objective of this study was to characterize YF virus (YFV) genomes and to identify spatial patterns to determine thedistribution and origin of YF cases in Minas Gerais, Espírito Santo and Rio de Janeiro, the most affected Brazilian states during the current YFV outbreak.

The structural proteins of epidemic and historical strains of Zika virus differ in their ability to initiate viral infection in human host cells

In this study researchers show that ZIKV containing BeH819015 structural proteins is much less efficient in cell-attachment leading to a reduced susceptibility ofepithelial A549 and neuronal SH-SY5Y cells to viral infection.

Limited Evidence for Infection of Urban and Peri-urban Nonhuman Primates with Zika and Chikungunya Viruses in Brazil

The authors of this study tested nonhuman primates (NHP) sampled during 2012 to 2017 in urban and peri-urban areas severely affected by ZIKV and CHIKV in Brazil. Seroprevalence and antibody titers were low for both viruses. Additionally, they found evidence for infection by heterologous viruses eliciting cross-reactive antibodies. These data suggest that urban or peri-urban NHP are not easily infected by ZIKV and CHIKV despite intense local transmission, and they may also imply that the ZIKV and CHIKV outbreaks in the Americas cannot be sustained in urban or peri-urban NHP once human population immunity limits urban transmission cycles.

Structural and Functional Basis of the Fidelity of Nucleotide Selection by Flavivirus RNA-Dependent RNA Polymerases

In this article, the authors review current knowledge on motifs A-G, defined as the conserved amino-acid sequence strings shared by enzymes, and their role on the structural and mechanistic basis of the fidelity of nucleotide selection and RNA synthesis by Flavivirus RdRps.

Emerging trends of Zika apprehension in an epidemic setting

The findings of this study have implications for the development of multifaceted infection control programs, including strategies for prevention and awareness, helping the population to develop an accurate perception of the threat they are facing and encouraging behavior changes.

The Zika Virus Epidemic in Brazil: From Discovery to Future Implications

The authors of this study discuss gaps in the knowledge and the challenges ahead to anticipate, prevent, and control emerging and re-emerging epidemics of arboviruses in Brazil and worldwide.

Recombinant Zika NS1 Protein Secreted from Vero Cells Is Efficient for Inducing Production of Immune Serum Directed against NS1 Dimer

The authors of this article demonstrated that recombinant ZIKV NS1 expressed in mammalian cells stably transduced with a lentiviral vector is suitable for inducing the production of specific antibody directed against NS1 oligomer. According to the authors, anti-ZIKV immune serum could be a great tool for the specific detection of secreted NS1 hexamer in human cells infected with ZIKV of African and Asia lineages, including contemporary epidemic strains.

Zika virus can be venereally transmitted between Aedes aegypti mosquitoes

In this study, researchers assessed for the first time the venereal transmission of ZIKV between Aedes aegypti under laboratory conditions. Their conclusion is that venereal transmission between Aedes mosquitoes might contribute to Zika virus maintenance in nature.

High Zika Virus Seroprevalence in Salvador, Northeastern Brazil Limits the Potential for Further Outbreaks

In this article, authors find that the high burden of Zika virus infection in a northeastern Brazilian metropolis questions the fate of the outbreak due to population protective immunity; that Zika virus infection predominantly affects geographic areas with low socioeconomic status, demonstrating a clear link between poverty and Zika virus infection; and, finally, additional evidence for the link between Zika virus infection and microcephaly.

High Zika Virus Seroprevalence in Salvador, Northeastern Brazil Limits the Potential for Further Outbreaks [Press Release]

A study published this week in mBio demonstrates rapid spread of ZIKV in Salvador, a metropolis in northeastern Brazil representing one of the most affected areas during the American ZIKV outbreak, and infection rates exceeding 60%.

Infection of a French Population of Aedes albopictus and of Aedes aegypti (Paea Strain) with Zika Virus Reveals Low Transmission Rates to These Vectors’ Saliva

This study shows that the extrinsic incubation period of Ae. aegypti for transmission is shorter than that of Ae. albopictus.

Zika virus displacement by a chikungunya outbreak in Recife, Brazil

In 2015–2016 in the Recife Metropolitan Region, the authors of this study detected the tail end of a Zika epidemic, which was displaced by a chikungunya epidemic. Few dengue cases were identified despite a high number of official dengue notifications in the area during this period. This study shows here important epidemiological features of these cases.

Culex quinquefasciatus mosquitoes do not support replication of Zika virus

The authors of this study found that Culex quinquefasciatus does not support ZIKV replication and Wolbachia is not involved in producing this phenotype. These mosquitoes are therefore very unlikely to play a role in transmission of ZIKV.

Characterization of the Zika virus induced small RNA response in Aedes aegypti cells

Results from this study suggest that ZIKV has mechanisms to evade mosquito innate immunity and it is therefore important to understand virus-vector interactions and the implications they have on transmission.

Evidence for congenital Zika virus infection from neutralizing antibody titers in maternal sera, north-eastern Brazil

Results from this study suggest that despite the inter-individual variability in immune responses, the magnitude of the maternal ZIKV-specific neutralizing antibody response may prove useful to corroborate congenital ZIKV infection, contributing to reliable estimates of the manifestation index of ZIKV-associated congenital disease. Further studies will be needed to evaluate the time-course of maternal neutralizing antibody responses to identify whether a high maternal PRNT titer can be used as an early marker of congenital infection aiding potential antiviral intervention strategies.

Replication of the Zika virus in different iPSC-derived neuronal cells and implications to assess efficacy of antivirals

This study demonstrates for the first time that motor neurons support ZIKV replication and these cells are as a consequence of ZIKV replication destroyed by the virus, and that human iPSC derived neuronal cells offer a physiologically relevant system to assess the potential antiviral effect of small molecule inhibitors of viral replication that are being developed to clear ZIKV infections in the nervous system.

Re-evaluation of routine dengue virus serology in travelers in the era of Zika virus emergence

Researchers have demonstrated that the recent ZIKV outbreak in Latin America substantially affects the DENV serology in routine diagnostic laboratories.

Neotropical bats that co-habit with humans function as dead-end hosts for dengue virus

Results from this study indicate that bats do not sustain sufficient virus amplification in order to function as reservoirs and exclude them as players in the dengue virus transmission cycle.

Zika plasma viral dynamics in nonhuman primates provides insights into early infection and antiviral strategies

Researchers found that in order for an antiviral treatment to effectively reduce the time to plasma viral clearance therapy should be initiated at the time of infection or given prophylactically.

Phenotypic Differences between Asian and African Lineage Zika Viruses in Human Neural Progenitor Cells

Taken together, this study shows that African and Asian ZIKV strains differ in their abilities to infect and replicate in different neural cells, as well as their abilities to cause cell death early after infection. This implies that caution is necessary against extrapolation of experimental data obtained using historical African ZIKV strains to the current outbreak. In addition, the fact that Asian ZIKV strains infect only a minority of cells with a relatively low burst size together with the lack of early cell death induction might contribute to their ability to cause chronic infections within the CNS.

Emerging arboviruses: Why today?

In this study, the authors select examples of (re)emerging pathogenic arboviruses and explain the reasons for their emergence and different patterns of dispersal, focusing particularly on the mosquito vectors which are important determinants of arbovirus emergence. They also attempt to identify arboviruses likely to (re)emerge in the future.

Establishment and cryptic transmission of Zika virus in Brazil and the Americas

Results from this study further indicate that viruses from northeast Brazil were important for the continental spread of ZIKV. Within Brazil, the authors find instances of virus lineage movement from northeast to southeast Brazil; most of these events are dated to the second half of 2014 and led to onwards transmission in Rio de Janeiro and São Paulo states. The authors infer that ZIKV lineages disseminated from northeast Brazil to elsewhere in Central America, the Caribbean, and South America.

Culex quinquefasciatus from areas with the highest incidence of microcephaly associated with Zika virus infections in the Northeast Region of Brazil are refractory to the virus

The study shows that Culex quinquefasciatus should not be considered a potential vector of ZIKV in Brazil.

Imipramine Inhibits Chikungunya Virus Replication in Human Skin Fibroblasts through Interference with Intracellular Cholesterol Trafficking

This study shows that imipramine strongly inhibits the replication of several Flaviviridae family members, including Zika, West Nile and Dengue virus. These data show that this compound is a potential drug candidate for anti-arboviral treatment.

Low seroprevalence of Zika virus in Cameroonian blood donors

The findings from this study indicate that the immunity of the Cameroonian population against ZIKV is low and that circulation in urban populations is uncommon. Hence, the risk of epidemic spread of ZIKV does exist. The virus is likely to be imported by infected travelers coming from epidemic areas and has the potential to be transmitted by local peri-domestic mosquitoes. This study provides biological evidence that such introduction would occur in populations that are globally immunologically naïve against ZIKV infection and live in areas where potential epidemic vectors exist.

Suramin inhibits Zika virus replication by interfering with virus attachment and release of infectious particles

The authors of this article describe inhibition of ZIKV replication by suramin, originally an anti-parasitic drug. They suggest that the inhibitory effect of suramin on ZIKV attachment and virion biogenesis and its broadspectrum activity warrant further evaluation of this compound as a potential therapeutic.

Successful technology transfer of a Zika vaccine developed by Institut Pasteur Shanghai-Chinese Academy of Sciences (IPS-CAS) to Chongqing Zhifei Biological Products Co., Ltd.

Institut Pasteur Shanghai-Chinese Academy of Sciences (IPS-CAS), a partner of the ZIKAlliance consortium, announced that it has entered into a collaborative research agreement with Chongqing Zhifei Biological Products Stock Co., Ltd. (Zhifei) for the clinical studies and commercialization of a recombinant Zika virus subunit vaccine developed by IPS-CAS.

Risk of microcephaly after Zika virus infection in Brazil, 2015 to 2016

The key message from this study is that the large uncertainty around the risk estimate needs to be further investigated because of a) the possible existence of co-factors that are yet to be validated, b) the assumptions that the authors needed to make in the absence of good data for the proportion of women who were infected during pregnancy.

Risk of microcephaly after Zika virus infection in Brazil, 2015 to 2016

The key message from this study is that the large uncertainty around the risk estimate needs to be further investigated because of a) the possible existence of co-factors that are yet to be validated, b) the assumptions that the authors needed to make in the absence of good data for the proportion of women who were infected during pregnancy.

Funding available for the SPSAS in Arbovirology in Brazil

15th International Dengue Course and ZIKAlliance WP1 meeting to be held in Cuba next August

Substrate selectivity of Dengue and Zika virus NS5 polymerase towards 2'-modified nucleotide analogues

In addition to representing the first ZIKV full-length NS5 activity report at the molecular level, this study should help the design of pan-flavivirus drugs aiming at the control of many Flavivirus members of this large family of emerging arboviruses, as well as understand the basis of re-purposing drugs against emerging viral diseases.

Zika Virus Methyltransferase: Structure and Functions for Drug Design Perspectives

The results outlined in the article contribute to a better understanding of the ZIKVMTase, a central player in viral replication and host innate immune response, and lay the basis for the development of potential antiviral drugs.

Real-Time Assessment of Health-Care Requirements During the Zika Virus Epidemic in Martinique

This study showcases the contribution of modeling to inform local health-care planning during an outbreak. Timely studies that estimate the proportion of infected persons that seek care are needed to improve the predictive power of such approaches.

Aedes aegypti Control Through Modernized, Integrated Vector Management

Researchers demonstrate that strategically combining the suppression methods with Wolbachia can generate a sustained control while mitigating the risks of inadvertent exacerbation of the wild mosquito population.

Zika virus causes supernumerary foci with centriolar proteins and impaired spindle positioning

The article concludes that infection with Flaviviridae can increase centrosome numbers and impair spindle positioning, thus potentially contributing to microcephaly in the case of Zika.

African and Asian Zika virus strains differentially induce early antiviral responses in primary human astrocytes

This study describes for the first time the specific antiviral gene expression in infected primary human astrocytes, the major glial cells within the central nervous system.

Zika and Other Emerging Viruses: Aiming at the Right Target

The article argues that the off-label use of drugs that may protect against Zika virus-induced brain damage has to be balanced with their risk during pregnancy.

From the Wellcome Trust: Zika: Why now and what next?

The Zika virus appears to have emerged from nowhere, causing widespread health concerns throughout the world after decades of relative silence.

CDC Video about Zika virus

The Zika virus is another wild card dealt to us by nature. It was first discovered in 1947.