ABSTRACT
Flaviviruses continue to emerge as global health threats. There are currently no Food and Drug Administration (FDA) approved antiviral treatments for flaviviral infections. Therefore, there is a pressing need to identify host and viral factors that can be targeted for effective therapeutic intervention. Type I interferon (IFN-I) production in response to microbial products is one of the host's first line of defense against invading pathogens. Cytidine/uridine monophosphate kinase 2 (CMPK2) is a type I interferon-stimulated gene (ISG) that exerts antiviral effects. However, the molecular mechanism by which CMPK2 inhibits viral replication is unclear. Here, we report that CMPK2 expression restricts Zika virus (ZIKV) replication by specifically inhibiting viral translation and that IFN-I- induced CMPK2 contributes significantly to the overall antiviral response against ZIKV. We demonstrate that expression of CMPK2 results in a significant decrease in the replication of other pathogenic flaviviruses including dengue virus (DENV-2), Kunjin virus (KUNV) and yellow fever virus (YFV). Importantly, we determine that the N-terminal domain (NTD) of CMPK2, which lacks kinase activity, is sufficient to restrict viral translation. Thus, its kinase function is not required for CMPK2's antiviral activity. Furthermore, we identify seven conserved cysteine residues within the NTD as critical for CMPK2 antiviral activity. Thus, these residues may form an unknown functional site in the NTD of CMPK2 contributing to its antiviral function. Finally, we show that mitochondrial localization of CMPK2 is required for its antiviral effects. Given its broad antiviral activity against flaviviruses, CMPK2 is a promising potential pan-flavivirus inhibitor.
Subject(s)
Flavivirus , Interferon Type I , Zika Virus Infection , Zika Virus , Humans , Zika Virus/genetics , Flavivirus/physiology , Virus Replication/physiology , Antiviral Agents/metabolism , Interferon Type I/metabolismABSTRACT
Antimicrobial peptides (AMPs) are major components of the innate immune defense. Accumulating evidence suggests that the antibacterial activity of many AMPs is dependent on the formation of amyloid-like fibrils. To identify novel fibril forming AMPs, we generated a spleen-derived peptide library and screened it for the presence of amyloidogenic peptides. This approach led to the identification of a C-terminal 32-mer fragment of alpha-hemoglobin, termed HBA(111-142). The non-fibrillar peptide has membranolytic activity against various bacterial species, while the HBA(111-142) fibrils aggregated bacteria to promote their phagocytotic clearance. Further, HBA(111-142) fibrils selectively inhibited measles and herpes viruses (HSV-1, HSV-2, HCMV), but not SARS-CoV-2, ZIKV and IAV. HBA(111-142) is released from its precursor by ubiquitous aspartic proteases under acidic conditions characteristic at sites of infection and inflammation. Thus, HBA(111-142) is an amyloidogenic AMP that may specifically be generated from a highly abundant precursor during bacterial or viral infection and may play an important role in innate antimicrobial immune responses.
Subject(s)
COVID-19 , Zika Virus Infection , Zika Virus , Humans , Peptides , Amyloid/chemistry , Anti-Bacterial Agents/pharmacology , HemoglobinsABSTRACT
The flavivirus genus contains several clinically important pathogens that account for tremendous global suffering. Primarily transmitted by mosquitos or ticks, these viruses can cause severe and potentially fatal diseases ranging from hemorrhagic fevers to encephalitis. The extensive global burden is predominantly caused by six flaviviruses: dengue, Zika, West Nile, yellow fever, Japanese encephalitis and tick-borne encephalitis. Several vaccines have been developed, and many more are currently being tested in clinical trials. However, flavivirus vaccine development is still confronted with many shortcomings and challenges. With the use of the existing literature, we have studied these hurdles as well as the signs of progress made in flavivirus vaccinology in the context of future development strategies. Moreover, all current licensed and phase-trial flavivirus vaccines have been gathered and discussed based on their vaccine type. Furthermore, potentially relevant vaccine types without any candidates in clinical testing are explored in this review as well. Over the past decades, several modern vaccine types have expanded the field of vaccinology, potentially providing alternative solutions for flavivirus vaccines. These vaccine types offer different development strategies as opposed to traditional vaccines. The included vaccine types were live-attenuated, inactivated, subunit, VLPs, viral vector-based, epitope-based, DNA and mRNA vaccines. Each vaccine type offers different advantages, some more suitable for flaviviruses than others. Additional studies are needed to overcome the barriers currently faced by flavivirus vaccine development, but many potential solutions are currently being explored.
Subject(s)
Flavivirus Infections , Flavivirus , Viral Vaccines , Yellow Fever , Zika Virus Infection , Zika Virus , Animals , Humans , Flavivirus/genetics , Mosquito Vectors , Yellow Fever/prevention & control , Zika Virus Infection/drug therapyABSTRACT
BACKGROUND: The United States Virgin Islands (USVI) Department of Health (DOH) conducted a second Zika health brigade (ZHB) in 2021 to provide recommended Zika-related pediatric health screenings, including vision, hearing, neurologic, and developmental screenings, for children in the USVI. This was replicated after the success of the first ZHB in 2018, which provided recommended Zika-related pediatric health screenings to 88 infants and children exposed to Zika virus (ZIKV) during pregnancy. METHODS: Ten specialty pediatric care providers were recruited and traveled to the USVI to conduct the screenings. USVI DOH scheduled appointments for children included in CDC's U.S. Zika Pregnancy and Infant Registry (USZPIR). During the ZHB, participants were examined by pediatric ophthalmologists, pediatric audiologists, and pediatric neurologists. We report the percentage of participants who were referred for additional follow-up care or given follow-up recommendations in the 2021 ZHB and compare these referrals and recommendations to those given in the 2018 ZHB. RESULTS: Thirty-three children born to mothers with laboratory evidence of ZIKV infection during pregnancy completed screenings at the 2021 ZHB, of which 15 (45%) children were referred for additional follow-up care. Ophthalmological screenings resulted in the highest number of new referrals for a specialty provider among ZHB participants, with 6 (18%) children receiving referrals for that specialty. Speech therapy was the most common therapy referral, with 10 (30%) children referred, of which 9 (90%) were among those who attended the 2018 ZHB. CONCLUSIONS: Thirty-three children in a jurisdiction with reduced access to healthcare specialists received recommended Zika-related pediatric health screenings at the ZHB. New and continuing medical and developmental concerns were identified and appropriate referrals for follow-up care and services were provided. The ZHB model was successful in creating connections to health services not previously received by the participants.
Subject(s)
Pregnancy Complications, Infectious , Zika Virus Infection , Zika Virus , Pregnancy , Infant , Female , Humans , Child , United States Virgin Islands , ParturitionABSTRACT
Viral infection in respiratory tract usually leads to cell death, impairing respiratory function to cause severe disease. However, the diversity of clinical manifestations of SARS-CoV-2 infection increases the complexity and difficulty of viral infection prevention, and especially the high-frequency asymptomatic infection increases the risk of virus transmission. Studying how SARS-CoV-2 affects apoptotic pathway may help to understand the pathological process of its infection. Here, we uncovered SARS-CoV-2 imployed a distinct anti-apoptotic mechanism via its N protein. We found SARS-CoV-2 virus-like particles (trVLP) suppressed cell apoptosis, but the trVLP lacking N protein didn't. Further study verified that N protein repressed cell apoptosis in cultured cells, human lung organoids and mice. Mechanistically, N protein specifically interacted with anti-apoptotic protein MCL-1, and recruited a deubiquitinating enzyme USP15 to remove the K63-linked ubiquitination of MCL-1, which stabilized this protein and promoted it to hijack Bak in mitochondria. Importantly, N protein promoted the replications of IAV, DENV and ZIKV, and exacerbated death of IAV-infected mice, all of which could be blocked by a MCL-1 specific inhibitor, S63845. Altogether, we identifed a distinct anti-apoptotic function of the N protein, through which it promoted viral replication. These may explain how SARS-CoV-2 effectively replicates in asymptomatic individuals without cuasing respiratory dysfunction, and indicate a risk of enhanced coinfection with other viruses. We anticipate that abrogating the N/MCL-1-dominated apoptosis repression is conducive to the treatments of SARS-CoV-2 infection as well as coinfections with other viruses.
Subject(s)
COVID-19 , Coinfection , Zika Virus Infection , Zika Virus , Humans , Animals , Mice , Myeloid Cell Leukemia Sequence 1 Protein/genetics , SARS-CoV-2 , COVID-19/genetics , Virus Replication/genetics , Ubiquitin-Specific ProteasesABSTRACT
Infection caused by the Zika virus (ZIKV) can lead to serious neurological complications such as microcephaly in neonates. At present, no approved ZIKV vaccine is available, but few vaccine candidates are undergoing clinical trial. One major challenge faced is antibody-dependent enhancement (ADE) reaction that may provoke severe outcome in subsequent infection by ZIKV or other flaviviruses. Thus, more efforts should be dedicated to understanding ADE in designing a safe and effective vaccine to minimize the consequence of the potentially fatal infection's complications and to tackle potential ZIKV reemergence. This review discusses different types of ZIKV vaccine candidates that are currently underway in various stages of preclinical and clinical evaluations.
Subject(s)
Viral Vaccines , Zika Virus Infection , Zika Virus , Infant, Newborn , Humans , Antibody-Dependent Enhancement , Antibodies, ViralABSTRACT
Japanese encephalitis virus (JEV) is the emerging and geographically expanding flavivirus and the major causative agent of encephalitis in humans in Asia. There are risks of JEV introduction into the Americas given a large population of amplifying hosts-pigs and wild boars, and insect vectors-Culex mosquitoes. There are emerging concerns about vector-free ways of flavivirus transmission, for example sexual and transplacental Zika virus transmissions, which may change flavivirus epidemiology and expand the geographical range to territories with no insect vectors. It is unknown whether JEV has tropism in the female lower reproductive tract and the potential for sexual transmission in humans. While clinical outcomes of transplacental JEV infection are described in humans and pigs, cellular targets and tissue tropism in the upper reproductive tract are also unknown. Here, we studied JEV infection phenotypes and host transcriptional responses in human reproductive epithelial cells. We found that JEV caused persistent infection and cytopathology in the vaginal epithelium, endometrial epithelium, and trophoblast. Human vaginal epithelial cells infected with JEV had altered transcriptional responses associated with inflammation and disruption of epithelial barrier function. Also, using pigs-the native amplifying host for JEV, we confirmed JEV tropism in the female lower and upper reproductive tracts. We discovered that JEV persists in the vaginal mucosa for at least 28 days and pigs shed the virus in vaginal secretions. We also found JEV persistence in the endometrium and placenta with transplacental and fetal infections. Altogether, we discovered that JEV targets the vaginal epithelium and has the potential for sexual transmission in humans. We also contributed to a better understanding of JEV pathogenesis during transplacental infection. Further studies are needed to better understand the interactions of JEV with reproductive tissues, how persistent infection affects female reproductive functions, and the risks for non-vector transmission.
Subject(s)
Culex , Encephalitis Virus, Japanese , Encephalitis, Japanese , Zika Virus Infection , Zika Virus , Animals , Encephalitis Virus, Japanese/genetics , Encephalitis, Japanese/epidemiology , Encephalitis, Japanese/veterinary , Epithelium , Female , Humans , Mosquito Vectors , Swine , Zika Virus/geneticsABSTRACT
Bacterial or viral infections, such as Brucella, mumps virus, herpes simplex virus, and Zika virus, destroy immune homeostasis of the testes, leading to spermatogenesis disorder and infertility. Of note, recent research shows that SARS-CoV-2 can infect male gonads and destroy Sertoli and Leydig cells, leading to male reproductive dysfunction. Due to the many side effects associated with antibiotic therapy, finding alternative treatments for inflammatory injury remains critical. Here, we found that Dmrt1 plays an important role in regulating testicular immune homeostasis. Knockdown of Dmrt1 in male mice inhibited spermatogenesis with a broad inflammatory response in seminiferous tubules and led to the loss of spermatogenic epithelial cells. Chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq) revealed that Dmrt1 positively regulated the expression of Spry1, an inhibitory protein of the receptor tyrosine kinase (RTK) signaling pathway. Furthermore, immunoprecipitation-mass spectrometry (IP-MS) and co-immunoprecipitation (Co-IP) analysis indicated that SPRY1 binds to nuclear factor kappa B1 (NF-κB1) to prevent nuclear translocation of p65, inhibit activation of NF-κB signaling, prevent excessive inflammatory reaction in the testis, and protect the integrity of the blood-testis barrier. In view of this newly identified Dmrt1- Spry1-NF-κB axis mechanism in the regulation of testicular immune homeostasis, our study opens new avenues for the prevention and treatment of male reproductive diseases in humans and livestock.
Subject(s)
COVID-19 , Rodent Diseases , Zika Virus Infection , Zika Virus , Humans , Male , Mice , Animals , Testis , NF-kappa B/metabolism , COVID-19/veterinary , SARS-CoV-2/metabolism , Homeostasis , Fertility , Zika Virus/metabolism , Zika Virus Infection/metabolism , Zika Virus Infection/veterinary , Membrane Proteins/metabolism , Phosphoproteins/metabolism , Phosphoproteins/pharmacology , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/pharmacology , Rodent Diseases/metabolismABSTRACT
Progress in stem cell research has revolutionized the medical field for more than two decades. More recently, the discovery of induced pluripotent stem cells (iPSCs) has allowed for the development of advanced disease modeling and tissue engineering platforms. iPSCs are generated from adult somatic cells by reprogramming them into an embryonic-like state via the expression of transcription factors required for establishing pluripotency. In the context of the central nervous system (CNS), iPSCs have the potential to differentiate into a wide variety of brain cell types including neurons, astrocytes, microglial cells, endothelial cells, and oligodendrocytes. iPSCs can be used to generate brain organoids by using a constructive approach in three-dimensional (3D) culture in vitro. Recent advances in 3D brain organoid modeling have provided access to a better understanding of cell-to-cell interactions in disease progression, particularly with neurotropic viral infections. Neurotropic viral infections have been difficult to study in two-dimensional culture systems in vitro due to the lack of a multicellular composition of CNS cell networks. In recent years, 3D brain organoids have been preferred for modeling neurotropic viral diseases and have provided invaluable information for better understanding the molecular regulation of viral infection and cellular responses. Here we provide a comprehensive review of the literature on recent advances in iPSC-derived 3D brain organoid culturing and their utilization in modeling major neurotropic viral infections including HIV-1, HSV-1, JCV, ZIKV, CMV, and SARS-CoV2.
Subject(s)
COVID-19 , Induced Pluripotent Stem Cells , Virus Diseases , Viruses , Zika Virus Infection , Zika Virus , Humans , Induced Pluripotent Stem Cells/metabolism , Zika Virus Infection/genetics , Endothelial Cells , RNA, Viral/metabolism , SARS-CoV-2 , Brain , Virus Diseases/metabolism , Organoids/metabolismABSTRACT
Monkeypox is a disease with pandemic potential. It is caused by the monkeypox virus (MPXV), a double-stranded DNA virus from the Poxviridae family, that replicates in the cytoplasm and must encode for its own RNA processing machinery including the capping machinery. Here, we present crystal structures of its 2'-O-RNA methyltransferase (MTase) VP39 in complex with the pan-MTase inhibitor sinefungin and a series of inhibitors that were discovered based on it. A comparison of this 2'-O-RNA MTase with enzymes from unrelated single-stranded RNA viruses (SARS-CoV-2 and Zika) reveals a conserved sinefungin binding mode, implicating that a single inhibitor could be used against unrelated viral families. Indeed, several of our inhibitors such as TO507 also inhibit the coronaviral nsp14 MTase.
Subject(s)
COVID-19 , Zika Virus Infection , Zika Virus , Humans , Methyltransferases/metabolism , SARS-CoV-2/genetics , Monkeypox virus/genetics , Monkeypox virus/metabolism , Viral Nonstructural Proteins/chemistry , RNA , Zika Virus/genetics , RNA, Viral/geneticsABSTRACT
Maternal infections during pregnancy, as cytomegalovirus and zika, have been consistently associated with severe newborn neurodevelopmental conditions, mainly related to vertical transmission and congenital infection. However, little is known about the neurodevelopmental consequences of maternal respiratory viral infections, which are the most prevalent infections during pregnancy. The recent COVID-19 pandemic has increased the interest in understanding the consequences of infections in offspring's development. This systematic review explores whether maternal gestational viral respiratory infections are associated with neurodevelopmental deviations in children below 10 years-old. The search was conducted in Pubmed, PsychInfo and Web of Science databases. 13 articles were revised, including information about maternal infection (Influenza, SARS-CoV-2 and unspecified respiratory infections) and offspring's neurodevelopment (global development, specific functions, temperament and behavioral/emotional aspects). Controversial results were reported regarding maternal respiratory infections during pregnancy and infants' neurodevelopment. Maternal infections seem to be associated with subtle alterations in some offspring's developmental subdomains, as early motor development, and attentional, behavioral/emotional minor problems. Further studies are needed to determine the impact of other psychosocial confounding factors.
Subject(s)
COVID-19 , Zika Virus Infection , Zika Virus , Pregnancy , Infant , Infant, Newborn , Child , Female , Humans , SARS-CoV-2 , Pandemics , Infectious Disease Transmission, VerticalABSTRACT
SARS-CoV-2 has caused a global pandemic with significant humanity and economic loss since 2020. Currently, only limited options are available to treat SARS-CoV-2 infections for vulnerable populations. In this study, we report a universal fluorescence polarization (FP)-based high throughput screening (HTS) assay for SAM-dependent viral methyltransferases (MTases), using a fluorescent SAM-analogue, FL-NAH. We performed the assay against a reference MTase, NSP14, an essential enzyme for SARS-CoV-2 to methylate the N7 position of viral 5'-RNA guanine cap. The assay is universal and suitable for any SAM-dependent viral MTases such as the SARS-CoV-2 NSP16/NSP10 MTase complex and the NS5 MTase of Zika virus (ZIKV). Pilot screening demonstrated that the HTS assay was very robust and identified two candidate inhibitors, NSC 111552 and 288387. The two compounds inhibited the FL-NAH binding to the NSP14 MTase with low micromolar IC50. We used three functional MTase assays to unambiguously verified the inhibitory potency of these molecules for the NSP14 N7-MTase function. Binding studies indicated that these molecules are bound directly to the NSP14 MTase with similar low micromolar affinity. Moreover, we further demonstrated that these molecules significantly inhibited the SARS-CoV-2 replication in cell-based assays at concentrations not causing cytotoxicity. Furthermore, NSC111552 significantly synergized with known SARS-CoV-2 drugs including nirmatrelvir and remdesivir. Finally, docking suggested that these molecules bind specifically to the SAM-binding site on the NSP14 MTase. Overall, these molecules represent novel and promising candidates to further develop broad-spectrum inhibitors for the management of viral infections.
Subject(s)
COVID-19 , Zika Virus Infection , Zika Virus , Humans , Methyltransferases/genetics , Methyltransferases/metabolism , SARS-CoV-2/genetics , High-Throughput Screening Assays , Viral Nonstructural Proteins/metabolism , Zika Virus/genetics , Zika Virus/metabolism , Binding Sites , RNA Caps/chemistry , RNA Caps/genetics , RNA Caps/metabolism , Fluorescence Polarization , RNA, Viral/geneticsABSTRACT
Zika virus (ZIKV) infection may cause serious birth defects and is a critical concern for women of child-bearing age in affected regions. A simple, portable, and easy-to-use ZIKV detection method would enable point-of-care testing, which may aid in prevention of the spread of the virus. Herein, we describe a reverse transcription isothermal loop-mediated amplification (RT-LAMP) method that detects the presence of ZIKV RNA in complex samples (e.g., blood, urine, and tap water). Phenol red is the colorimetric indicator of successful amplification. Color changes based on the amplified RT-LAMP product from the presence of viral target are monitored using a smartphone camera under ambient light conditions. A single viral RNA molecule per µL can be detected in as quickly as 15 min using this method with 100% sensitivity and 100% specificity in blood and tap water, while 100% sensitivity and 67% specificity in urine. This platform can also be used to identify other viruses including SARS-CoV-2 and improve the current state of field-based diagnostics.
Subject(s)
COVID-19 , Zika Virus Infection , Zika Virus , Female , Humans , Zika Virus/genetics , Microfluidics , Smartphone , Sensitivity and Specificity , SARS-CoV-2ABSTRACT
PURPOSE OF REVIEW: The most common infectious etiologies of meningitis and encephalitis are viruses. In this review, we will discuss current epidemiology, prevention, diagnosis, and treatment of the most common causes of viral meningitis and encephalitis worldwide. RECENT FINDINGS: Viral meningitis and encephalitis are increasingly diagnosed as molecular diagnostic techniques and serologies have become more readily available worldwide but recent progress in novel antiviral therapies remains limited. Emerging and re-emerging viruses that have caused endemic or worldwide outbreaks or epidemics are arboviruses (e.g., West Nile virus, Japanese encephalitis, Tick borne encephalitis, Dengue, Zika, Toscana), enteroviruses (e.g., Enterovirus 71, Enterovirus D68), Parechoviruses, respiratory viruses [e.g., severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza, metapneumoviruses, measles, mumps], and herpes viruses [e.g., herpes simplex virus (HSV) type 1 (HSV-1), HSV-2, human herpes (HV) 6, varicella zoster virus (VZV)]. Future efforts should concentrate in increasing availability for those viruses with effective vaccination [e.g., Japanese encephalitis, Tick borne encephalitis, varicella zoster viruses, SARS-CoV-2, influenza], prompt initiation of those with encephalitis with treatable viruses (e.g., HSV-1, VZV), increasing the diagnostic yield by using novel techniques such as metagenomic sequencing and avoiding unnecessary antibiotics in those with viral meningitis or encephalitis. SUMMARY: We review the current epidemiology, clinical presentation, diagnosis, and treatment of the common causative agents of viral meningitis and encephalitis worldwide.
Subject(s)
COVID-19 , Encephalitis , Herpesvirus 1, Human , Influenza, Human , Meningitis, Viral , Viruses , Zika Virus Infection , Zika Virus , Humans , COVID-19/epidemiology , SARS-CoV-2 , Herpesvirus 3, HumanABSTRACT
RNA viruses continue to remain a threat for potential pandemics due to their rapid evolution. Potentiating host antiviral pathways to prevent or limit viral infections is a promising strategy. Thus, by testing a library of innate immune agonists targeting pathogen recognition receptors, we observe that Toll-like receptor 3 (TLR3), stimulator of interferon genes (STING), TLR8, and Dectin-1 ligands inhibit arboviruses, Chikungunya virus (CHIKV), West Nile virus, and Zika virus to varying degrees. STING agonists (cAIMP, diABZI, and 2',3'-cGAMP) and Dectin-1 agonist scleroglucan demonstrate the most potent, broad-spectrum antiviral function. Furthermore, STING agonists inhibit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and enterovirus-D68 (EV-D68) infection in cardiomyocytes. Transcriptome analysis reveals that cAIMP treatment rescue cells from CHIKV-induced dysregulation of cell repair, immune, and metabolic pathways. In addition, cAIMP provides protection against CHIKV in a chronic CHIKV-arthritis mouse model. Our study describes innate immune signaling circuits crucial for RNA virus replication and identifies broad-spectrum antivirals effective against multiple families of pandemic potential RNA viruses.
Subject(s)
COVID-19 , Chikungunya virus , RNA Viruses , Zika Virus Infection , Zika Virus , Animals , Mice , SARS-CoV-2 , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Chikungunya virus/physiology , Immunity, InnateABSTRACT
Microphysiological systems (MPS) are 2D or 3D multicellular constructs able to mimic tissue microenvironments. The latest models encompass a range of techniques, including co-culturing of various cell types, utilization of scaffolds and extracellular matrix materials, perfusion systems, 3D culture methods, 3D bioprinting, organ-on-a-chip technology, and examination of tissue structures. Several human brain 3D cultures or brain MPS (BMPS) have emerged in the last decade. These organoids or spheroids are 3D culture systems derived from induced pluripotent cells or embryonic stem cells that contain neuronal and glial populations and recapitulate structural and physiological aspects of the human brain. BMPS have been introduced recently in the study and modeling of neuroinfectious diseases and have proven to be useful in establishing neurotropism of viral infections, cell-pathogen interactions needed for infection, assessing cytopathological effects, genomic and proteomic profiles, and screening therapeutic compounds. Here we review the different methodologies of organoids used in neuroinfectious diseases including spheroids, guided and unguided protocols as well as microglia and blood-brain barrier containing models, their specific applications, and limitations. The review provides an overview of the models existing for specific infections including Zika, Dengue, JC virus, Japanese encephalitis, measles, herpes, SARS-CoV2, and influenza viruses among others, and provide useful concepts in the modeling of disease and antiviral agent screening.
Subject(s)
COVID-19 , Induced Pluripotent Stem Cells , Zika Virus Infection , Zika Virus , Humans , Microphysiological Systems , Proteomics , RNA, Viral , COVID-19/pathology , SARS-CoV-2 , Brain , Zika Virus Infection/pathology , Induced Pluripotent Stem Cells/physiologyABSTRACT
BACKGROUND: Rapid data sharing can maximize the utility of data. In epidemics and pandemics like Zika, Ebola, and COVID-19, the case for such practices seems especially urgent and warranted. Yet rapidly sharing data widely has previously generated significant concerns related to equity. The continued lack of understanding and guidance on equitable data sharing raises the following questions: Should data sharing in epidemics and pandemics primarily advance utility, or should it advance equity as well? If so, what norms comprise equitable data sharing in epidemics and pandemics? Do these norms address the equity-related concerns raised by researchers, data providers, and other stakeholders? What tensions must be balanced between equity and other values? METHODS: To explore these questions, we undertook a systematic scoping review of the literature on data sharing in epidemics and pandemics and thematically analyzed identified literature for its discussion of ethical values, norms, concerns, and tensions, with a particular (but not exclusive) emphasis on equity. We wanted to both understand how equity in data sharing is being conceptualized and draw out other important values and norms for data sharing in epidemics and pandemics. RESULTS: We found that values of utility, equity, solidarity, and reciprocity were described, and we report their associated norms, including researcher recognition; rapid, real-time sharing; capacity development; and fair benefits to data generators, data providers, and source countries. The value of utility and its associated norms were discussed substantially more than others. Tensions between utility norms (e.g., rapid, real-time sharing) and equity norms (e.g., researcher recognition, equitable access) were raised. CONCLUSIONS: This study found support for equity being advanced by data sharing in epidemics and pandemics. However, norms for equitable data sharing in epidemics and pandemics require further development, particularly in relation to power sharing and participatory approaches prioritizing inclusion. Addressing structural inequities in the wider global health landscape is also needed to achieve equitable data sharing in epidemics and pandemics.
Subject(s)
COVID-19 , Zika Virus Infection , Zika Virus , Humans , Information Dissemination , Organizations , Pandemics , SARS-CoV-2 , Zika Virus Infection/epidemiologyABSTRACT
Nonstructural protein 1 (NS1) is a glycoprotein among the flavivirus genus. It is found in both membrane-associated and soluble secreted forms, has an essential role in viral replication, and modulates the host immune response. NS1 is secreted from infected cells within hours after viral infection, and thus immunodetection of NS1 can be used for early serum diagnosis of dengue fever infections instead of real-time (RT)-PCR. This method is fast, simple, and affordable, and its availability could provide an easy point-of-care testing solution for developing countries. Early studies show that detecting NS1 in cerebrospinal fluid (CSF) samples is possible and can improve the surveillance of patients with dengue-associated neurological diseases. NS1 can be detected postmortem in tissue specimens. It can also be identified using noninvasive methods in urine, saliva, and dried blood spots, extending the availability and effective detection period. Recently, an enzyme-linked immunosorbent assay (ELISA) assay for detecting antibodies directed against Zika virus NS1 has been developed and used for diagnosing Zika infection. This NS1-based assay was significantly more specific than envelope protein-based assays, suggesting that similar assays might be more specific for other flaviviruses as well. This review summarizes the knowledge on flaviviruses' NS1's potential role in antigen and antibody diagnosis.
Subject(s)
Flavivirus Infections , Zika Virus Infection , Zika Virus , Humans , Antibodies , Autopsy , Biological Assay , Flavivirus Infections/diagnosis , Zika Virus Infection/diagnosisABSTRACT
The functionality and performance of public health programmes at all levels of government play a critical role in preventing, detecting, mitigating and responding to public health threats, including infectious disease outbreaks. Multiple and concurrent outbreaks in recent years, such as COVID-19, Ebola and Zika, have highlighted the importance of documenting lessons learnt from public health responses of national and global agencies. In February 2020, the US Centers for Disease Control and Prevention (CDC) Center for Global Health (CGH) activated the Measles Incident Management System (MIMS) to accelerate the ability to detect, mitigate and respond to measles outbreaks globally and advance progress towards regional measles elimination goals. The activation was triggered by a global resurgence in reported measles cases during 2018-2019 and supported emergency response activities conducted by partner organisations and countries. MIMS leadership decided early in the response to form an evaluation team to design and implement an evaluation approach for producing real-time data to document progress of response activities and inform timely decision-making. In this manuscript, we describe how establishing an evaluation unit within MIMS, and engaging MIMS leadership and subject matter experts in the evaluation activities, was critical to monitor progress and document lessons learnt to inform decision making. We also explain the CDC's Framework for Evaluation in Public Health Practice applied to evaluate the dynamic events throughout the MIMS response. Evaluators supporting emergency response should use a flexible framework that can be adaptable in dynamic contexts and document response activities in real-time.
Subject(s)
COVID-19 , Hemorrhagic Fever, Ebola , Measles , Zika Virus Infection , Zika Virus , United States/epidemiology , Humans , COVID-19/epidemiology , Disease Outbreaks/prevention & control , Hemorrhagic Fever, Ebola/epidemiology , Measles/epidemiology , Measles/prevention & control , Zika Virus Infection/epidemiology , Centers for Disease Control and Prevention, U.S.ABSTRACT
Ivermectin (IVM) is a drug from the group of anthelmintics used in veterinary and human medicine. Recently, interest in IVM has increased as it has been used for the treatment of some malignant diseases, as well as viral infections caused by the Zika virus, HIV-1 and SARS-CoV-2. The electrochemical behaviour of IVM was investigated using cyclic (CV), differential pulse (DPV) and square wave voltammetry (SWV) at glassy carbon electrode (GCE). IVM showed independent oxidation and reduction processes. The effect of pH and scan rate indicated the irreversibility of all processes and confirmed the diffusion character of oxidation and reduction as an adsorption-controlled process. Mechanisms for IVM oxidation at the tetrahydrofuran ring and reduction of the 1,4-diene structure in the IVM molecule are proposed. The redox behaviour of IVM in a biological matrix (human serum pool) showed a pronounced antioxidant potential similar to that of Trolox during short incubation, whereas a prolonged stay among biomolecules and in the presence of an exogenous pro-oxidant (tert-butyl hydroperoxide, TBH) resulted in a loss of its antioxidant effect. The antioxidant potential of IVM was confirmed by voltametric methodology which is proposed for the first time.