Within the Zika virus (ZIKV) research community, a new and remarkable kind of collaboration is taking placeby EU Zika Consortia
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.
Re-visiting the evolution, dispersal and epidemiology of Zika virus in Asia. A commentary from the authors.by Pettersson et al.
Pettersson et al provide a short commentary on their research article Re-visiting the evolution, dispersal and epidemiology of Zika virus in Asia published in Emerging Microbes & Infections in May 2018. This work was supported by the European Union’s Horizon 2020 Research and Innovation Programme under ZIKAlliance Grant Agreement no. 734548 and ZikaPLAN Grant Agreement no. 734584.
In order to overcome potential technological issues related to the study of arboviruses, the authors of this study designed an improved DNA transfection protocol for insect cells and then demonstrated that the simple and flexible ISA (Infectious Subgenomic Amplicons) reverse-genetics method can be efficiently applied to both mammalian and mosquito cells to generate in days recombinant infectious positive-stranded RNA viruses belonging to genera Flavivirus (Japanese encephalitis, Yellow fever, West Nile and Zika viruses) and Alphavirus (Chikungunya virus).
The authors of this study developed novel multiplex real-time reverse transcription PCRs. The new PCRs enable yellow fever (YFV) detection with diagnostic sensitivity. Although the dual-target assay is superior to the single-target assay in sensitivity and robustness to target competition, the single-target assay – as stated by the researchers – may be advantageous in resource-limited settings and may be more convenient for multiplex usage in combination with assays targeting co-circulating arboviruses, such as chikungunya, Zika, and dengue viruses.
During the European Congress on Tropical Medicine and International Health (ECTMIH) conference in Antwerp, the three EU-funded Zika Consortia, ZIKAlliance, ZIKAction and ZikaPLAN organized a joint symposium, with an afternoon of presentations packed with up-to-date science regarding ZIKV on October 17th.
In this work, the authors analysed the transmission dynamics of the Wynwood outbreak, recorded in Florida at the end of July 2016, using a mathematical model calibrated to outbreak data, and assessed the efficacy of the implemented vector control measures in containing viral transmission. Results from this analysis provide useful insights for prevention and control of possible future outbreaks in European areas.
In this letter, the authors address the need for curation and standardized annotation of ZIKV reference genomes in order to guide researchers and clinicians in genomic analyses and the translation of research findings.
Researchers have demonstrated that the recent ZIKV outbreak in Latin America substantially affects the DENV serology in routine diagnostic laboratories.
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.
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 virusby Fernandes et al.
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 Traffickingby Wichit et al.
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.
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 particlesby Albulescu et al.
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.
Based on the reported data from Brazil in 2015/16, this publication describes a plausible range for the risk of microcephaly in women who were infected with Zika virus during pregnancy compared to those who were not infected. The key message 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 need be made for the proportion of women who were infected during pregnancy.
Substrate selectivity of Dengue and Zika virus NS5 polymerase towards 2'-modified nucleotide analoguesby Potisopon et al.
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.
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.
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 astrocytesby Hamel et al.
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.
This pioneering study suggests that the study of blood donors during outbreaks of emerging pathogens has become a key element of epidemiological surveillance.
This study highlights the dual role of Axl during ZIKV infection of glial cells: promoting viral entry and modulating innate immune responses. Therefore, inhibiting Axl function may represent a potential target for future antiviral therapies.
By using the bacterium-free ‘Infectious Subgenomic Amplicons’ (ISA) method, this study provides the scientific community with two simple and performing reverse genetics systems for ZIKV.
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.