Several genetic variations of Severe Acute Respiratory Ryndrome coronavirus (SARS-CoV) are continuously arising due to the uncontrolled dissemination of the virus during the pandemic. Omicron (B.1.1.529), the most prevalent variation of concern, has demonstrated extraordinary proliferation and pathogenicity and has emerged as the dominant variant as it has inflicted mass casualties worldwide. Impeding the expression of 3CLpro, a coronavirus protease that is essential for digesting the RNA polyproteins, and the human angiotensin-converting enzyme 2 (ACE2) that serves as a receptor for the viral protein is identified as a competent therapeutic target. In the current study, human ACE2 and the viral 3CLpro complex was the target for the designing of novel drugs against the lethal virus. The docked complex was validated by Procheck, and the covid ligand library was investigated for its pharmacological efficacy using admetSAR 2.0. The molecular docking study was performed with the screened compounds obtained from the PubChem database against the docked protein complex. The molecular dynamics simulation study was effectuated using Desmond Schrodinger 2019.2 to assess the stability and interaction of the 3CLpro-ACE2 complex with the ligand followed by normal mode analysis. In addition to having favorable pharmacological qualities, the ligand 1-(4-fluorophenyl)-N'-(4-methylphenyl) propane-1,3-diamine exhibited the best binding affinity with the complex. Consequently, this compound can be used to develop anti-covid medications to combat complications associated with Omicron infection.

From the metabolite ecology (KNapSAcK) and herbs medicinal plants, phytochemistry, and therapeutics (IMPPAT) databases, the phytoconstituents from the herbal natural inhalant (turmeric) were taken. More samples of the phytoconstituents that adhere to drug likeness limits were obtained for in-silico research. To identify SARS-CoV-2 inhibitors, the Drug Likeness and ADMET experiments were used to screen volatile molecules from natural medicinal inhalants. The seven chemicals that make up turmeric all adhere to the ADMET restrictions and interact well with the Covid-19 proteins. Two active molecules are predicted by molecular docking studies to have strong binding affinity with the Sars-CoV-2 proteins (6LU7 and 6M0J). Based on this study 2 phytochemicals from turmeric, they have good binding affinity. DFT computing is applied to elucidate the molecular characteristics, and the molecular electrostatic potential (MEP) is generated to analyses the distribution of charges. These substances could be further subjected to in-vitro studies to evaluate their efficacy against Covid-19.

SUMMARY Sequential dengue virus (DENV) infections often generate neutralizing antibodies against all four DENV serotypes and sometimes, Zika virus. Characterizing cross-flavivirus broadly neutralizing antibody (bnAb) responses can inform countermeasure strategies that avoid infection enhancement associated with non-neutralizing antibodies. Here, we used single cell transcriptomics to mine the bnAb repertoire following secondary DENV infection. We identified several new bnAbs with comparable or superior breadth and potency to known bnAbs, and with distinct recognition determinants. Unlike all known flavivirus bnAbs, which are IgG1, one newly identified cross-flavivirus bnAb (F25.S02) was derived from IgA1. Both IgG1 and IgA1 versions of F25.S02 and known bnAbs displayed neutralizing activity, but only IgG1 enhanced infection in monocytes expressing IgG and IgA Fc receptors. Moreover, IgG-mediated enhancement of infection was inhibited by IgA1 versions of bnAbs. We demonstrate a role for IgA in flavivirus infection and immunity with implications for vaccine and therapeutic strategies.

Interferon ε (IFNε) is a unique type I IFN that has been implicated in host defense against sexually transmitted infections (STIs). Zika virus (ZIKV), an emerging pathogen, can infect the female reproductive tract (FRT) and cause devastating diseases, particularly in pregnant women. How IFNε contributes to protection against ZIKV infection in vivo is unknown. Here, we show that IFNε plays a critical role in host protection against vaginal ZIKV infection in mice. We found that IFNε was expressed not only by epithelial cells in the FRT, but also by certain immune and other cells at baseline or after exposure to viruses or specific TLR agonists. IFNε-deficient mice exhibited abnormalities in the epithelial border and underlying tissue in the cervicovaginal tract, and these defects were associated with increased susceptibility to vaginal, but not subcutaneous ZIKV infection. IFNε-deficiency resulted in an increase in magnitude, duration, and depth of ZIKV infection in the FRT. Critically, intravaginal administration of recombinant IFNε protected Ifnε -/- mice and highly susceptible Ifnar1 -/- mice against vaginal ZIKV infection, indicating that IFNε was sufficient to provide protection even in the absence of signals from other type I IFNs and in an IFNAR1-independent manner. Our findings reveal a potentially critical role for IFNε in mediating protection against transmission of ZIKV in the context of sexual contact. Significance Interferon ε (IFNε), a unique Type I IFN that is highly expressed in the epithelium of the female reproductive tract (FRT), is thought to protect the host against sexually transmitted infections (STIs) but the mechanism of action is not defined. Zika virus (ZIKV), a causative agent for preterm birth and other severe diseases in pregnant women, can be spread through vaginal transmission. Here, we show that mice lacking the Ifnε gene have abnormal epithelial development and tissue architecture in the cervicovaginal tract. The role of IFNε in protecting host against ZIKV is FRT-specific and is independent of IFNAR1 signaling. Our findings suggest potential preventive strategies based on harnessing mucosal immunity against STIs.

Worldwide outbreaks of hand, foot, and mouth disease (HFMD) are caused by enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16). Since no anti-HFMD drugs are currently available, it is interesting to study potential viral inhibitors. Rupintrivir is a rhinovirus 3C protease (3Cpro) inhibitor with apparent inhibitory activity against HFMD. This study constructs pharmacophore models of the EV-A71 and CV-A16 3Cpro complexed with rupintrivir using molecular dynamics (MD) simulations. Both models had similar pharmacophore features, including hydrogen bond donors and acceptors and hydrophobic interactions. These pharmacophore models were then used as a template to screen 39 flavonoid compounds as potential novel inhibitors. Diosmin, epigallocatechin gallate (EGCG), and RTH-011 showed high binding affinities for EV-A71 and CV-A16 3Cpro. They formed hydrogen bonds with important surrounding residues in both proteins, including H40, L127, T142, A144, T145, H161, I162, G163, and G164. In addition, their effective concentrations against rhabdomyosarcoma (RD) cell infection by EV-A71 and CV-A16 were determined. EGCG had the highest half maximal effective concentration (EC50) of 12.86 ± 1.30 µM for EV-A71 and 15.54 ± 1.50 µM for CV-A16, while diosmin had EC50 of 21.01±1.57 µM for EV-A71 and 30.68 ± 3.25 µM for CV-A16. Both compounds were non-toxic in RD cells, with 50% cytotoxic concentrations of >100 µM for EGCG and >500 µM for diosmin. In addition, MD simulation analysis showed that EGCG had a higher binding affinity than diosmin, supported by its significantly lower solvated binding free energies and greater numbers of contact atoms and key binding residues. Moreover, previous studies reported EGCG’s inhibitory effect on other viruses, such as severe acute respiratory syndrome coronavirus 2. Therefore, our findings suggest that EGCG can effectively inhibit the EV-A71 and CV-A16 3Cpro.

Maternal Zika virus (ZIKV) infection during pregnancy can associate with severe intrauterine growth restriction (IUGR), placental damage, and metabolism disturbance, as well as newborn neurological abnormalities. Here, we investigated whether maternal ZIKV infection affects placental nutrient transporters and nutrient-sensitive pathways. Immunocompetent (C57BL/6) mice were injected with Low (10 3 PFU-ZIKV PE243 ) and High (5×10 7 PFU-ZIKV PE243 ) ZIKV titers at gestational day (GD) 12.5, for tissue collection at GD18.5 (term). Feto-placental growth of male fetuses was dramatically affected by ZIKV, whereas no differences were observed in female fetuses. ZIKV promoted increased expression of glucose transporter type 1 ( Slc2a1 /Glut1) and decreased levels of glucose-6-phosphate in female placentas, with no differences in amino-acid transport potential. In contrast, glucose transport in male placentas was not affected by ZIKV, whilst a decreased placental protein expression of sodium-coupled neutral amino acid 2 (Snat2) was detected in the male low-dose ZIKV-infected group. There were also sex-dependent differences in the hexosamine biosynthesis pathway (HBP) and O-GlcNAcylation in ZIKV infected pregnancies, showing that ZIKV can cause disturbance in the nutrient handling in the placental tissue. Our findings thus identify relevant molecular alterations in the placenta caused by maternal ZIKV infection related to nutrient transport and availability. Notably, our results suggest that female and male placentas adopt different strategies to cope with the altered metabolic state caused by ZIKV. This may have relevance for understanding the effects of congenital Zika syndrome and could potentially assist future therapeutic strategies. Author Summary The Zika virus (ZIKV) has emerged as a major global health concern in the past decade. ZIKV infection during pregnancy can cause infants to be born with microcephaly and fetal growth restriction, among other pregnancy complications. Currently, the number of cases of ZIKV disease declined onwards globally. However, transmission persists at low levels in several countries in the Americas and other endemic regions, with neither a licensed vaccine nor an antiviral drug available for prevention and treatment. Here, we use a mice model of maternal ZIKV infection to analyze placental nutrient transporters and nutrient-sensitive pathways as a potential link to the complications related to congenital ZIKV infection. We found that feto-placental growth of male fetuses was dramatically affected by ZIKV, whereas no differences were observed in female fetuses. We also found that placental nutrient transporters and nutrient-sensitive pathways were altered in response to ZIKV infection, depending on the fetal sex. Our study presents relevant molecular alterations caused by maternal ZIKV infection and suggests that female and male placentas adopt different strategies in response to the altered environment caused by ZIKV. Our observations may have relevance for understanding the effects of ZIKV infection and could potentially assist future therapeutic strategies.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, is associated with a high mortality rate. The clinical course is attributed to the severity of pneumonia and systemic complications. In COVID-19 patients and murine models of SARS-CoV-2 infection, the disease may be accompanied by over-exuberant production of cytokines, leading to accumulation of immune cells in affected organs such as lungs. Previous reports have shown that SARS-CoV-2 infection antagonizes interferon (IFN)-dependent antiviral response, thereby preventing the expression of IFN-stimulated genes (ISGs). Lower IFN levels have been linked to more severe COVID-19. Interleukin 27 (IL27) is a heterodimeric cytokine composed of IL27p28 and EBI3 subunits that induce both pro- and anti-inflammatory responses. Recently, we and others have reported that IL27 also induces a strong antiviral response in an IFN-independent manner. Here, we investigated transcription levels of both IL27 subunits in COVID-19 patients. Results show that SARS-CoV-2 infection modulates TLR1/2-MyD88 signaling in PBMCs and monocytes, and induces NF-κB activation and robust pro-inflammatory response-dependent NF-κB-target genes expression, including EBI3; as well as it activates IRF1 signaling, that induces IL27p28 mRNA expression. Results suggest that IL27 induces a robust STAT1-dependent pro-inflammatory and antiviral response in an IFN-independent manner in COVID-derived PBMCs, and Monocytes as a function of severe COVID-19 clinical course. Similar results were observed in SARS-CoV-2 Spike protein-stimulated macrophages. Thus, IL27 can trigger host antiviral response suggesting the possibility of novel therapeutics against SARS-CoV-2 infection in humans.

Background: The study of the etiology of acute febrile illness (AFI) has historically been designed as a prevalence of pathogens detected from a case series. This strategy has an inherent unrealistic assumption that all pathogen detection allows for causal attribution, despite known asymptomatic carriage of the principal causes of acute febrile illness in most low- and middle-income countries (LMICs). We designed a semi-quantitative PCR in a modular format to detect bloodborne agents of acute febrile illness that encompassed common etiologies of AFI in the region, etiologies of recent epidemics, etiologies that require an immediate public health response and additional pathogens of unknown endemicity. We then designed a study that would delineate background levels of transmission in the community in the absence of symptoms to provide corrected estimates of attribution for the principal determinants of AFI. Methods: A case-control study of acute febrile illness in patients ten years or older seeking health care in Iquitos, Loreto, Peru, was planned. Upon enrollment, we will obtain blood, saliva, and mid-turbinate nasal swabs at enrollment with a follow-up visit on day 21-28 following enrollment to attain vital status and convalescent saliva and blood samples, as well as a questionnaire including clinical, socio-demographic, occupational, travel, and animal contact information for each participant. Whole blood samples are to be simultaneously tested for 32 pathogens using TaqMan array cards. Mid-turbinate samples will be tested for SARS-CoV-2, Influenza A and Influenza B. Conditional logistic regression models will be fitted treating case/control status as the outcome and with pathogen-specific sample positivity as predictors to attain estimates of attributable pathogen fractions for AFI. Discussion: The modular PCR platforms will allow for reporting of all primary results of respiratory samples within 72 hours and blood samples within one week, allowing for results to influence local medical practice and enable timely public health responses. The inclusion of controls will allow for a more accurate estimate of the importance of specific, prevalent pathogens as a cause of acute illness. Study Registration: Project 1791, Registro de Proyectos de Investigación en Salud Pública (PRISA), Instituto Nacional de Salud, Perú.

Zika virus (ZIKV) is a Flavivirus responsible for recent epidemics in Pacific Islands and in the Americas. In humans, the consequences of ZIKV infection range from asymptomatic infection to severe neurological disease such as Guillain-Barré syndrome or fetal neurodevelopmental defects, suggesting, among other factors, the influence of host genetic variants. We previously reported similar diverse outcomes of ZIKV infection in mice of the Collaborative Cross (CC), a collection of inbred strains with large genetic diversity. CC071/TauUnc (CC071) was the most susceptible CC strain with severe symptoms and lethality. Notably, CC071 has been recently reported to be also susceptible to other flaviviruses including dengue virus, Powassan virus, West Nile virus, and to Rift Valley fever virus. To identify the genetic origin of this broad susceptibility, we investigated ZIKV replication in mouse embryonic fibroblasts (MEFs) from CC071 and two resistant strains. CC071 showed uncontrolled ZIKV replication associated with delayed induction of type-I interferons (IFN-I). Genetic analysis identified a mutation in the Irf3 gene specific to the CC071 strain which prevents the protein phosphorylation required to activate interferon beta transcription. We demonstrated that this mutation induces the same defective IFN-I response and uncontrolled viral replication in MEFs as an Irf3 knock-out allele. By contrast, we also showed that Irf3 deficiency did not induce the high plasma viral load and clinical severity observed in CC071 mice and that susceptibility alleles at other genes, not associated with the IFN-I response, are required. Our results provide new insight into the in vitro and in vivo roles of Irf3 , and into the genetic complexity of host responses to flaviviruses. Author summary Recent ZIKV outbreaks led to millions of infected people, with rare but severe complications such as Guillain-Barré syndrome and encephalitis in adults suggesting that host genes influence the susceptibility to severe forms of infection. We previously reported the importance of host genes in ZIKV pathogenesis using a panel of genetically diverse mouse strains and identified CC071 as the most susceptible strain. Importantly, this mouse strain has been shown by others to be also susceptible to several other RNA viruses. Through a combination of functional and genetic approaches in a cellular model, we identified a mutation in the Irf3 gene which plays a key role in activating the expression of interferon beta to induce the type I interferon response, the first line of host defense against the virus. This mutation fully explains the high viral replication observed in CC071 cells. However, it was not able to induce the elevated viremia and the symptoms displayed by CC071 ZIKV-infected mice, unraveling the implication of other host genes which are not associated with the type I interferon response. Because of the broad susceptibility of CC071 to multiple viruses, our results have implications beyond ZIKV infection and contribute to shedding light on the plurality of host mechanisms fighting infectious diseases.

Summary Development of vaccines and therapeutics that are broadly effective against known and emergent coronaviruses is an urgent priority. Current strategies for developing pan-coronavirus countermeasures have largely focused on the receptor binding domain ( RBD ) and S2 regions of the coronavirus Spike protein; it has been unclear whether the N-terminal domain ( NTD ) is a viable target for universal vaccines and broadly neutralizing antibodies ( Abs ). Additionally, many RBD-targeting Abs have proven susceptible to viral escape. We screened the circulating B cell repertoires of COVID-19 survivors and vaccinees using multiplexed panels of uniquely barcoded antigens in a high-throughput single cell workflow to isolate over 9,000 SARS-CoV-2-specific monoclonal Abs ( mAbs ), providing an expansive view of the SARS-CoV-2-specific Ab repertoire. We observed many instances of clonal coalescence between individuals, suggesting that Ab responses frequently converge independently on similar genetic solutions. Among the recovered antibodies was TXG-0078, a public neutralizing mAb that binds the NTD supersite region of the coronavirus Spike protein and recognizes a diverse collection of alpha- and beta-coronaviruses. TXG-0078 achieves its exceptional binding breadth while utilizing the same VH1-24 variable gene signature and heavy chain-dominant binding pattern seen in other NTD supersite-specific neutralizing Abs with much narrower specificity. We also report the discovery of CC24.2, a pan-sarbecovirus neutralizing mAb that targets a novel RBD epitope and shows similar neutralization potency against all tested SARS-CoV-2 variants, including BQ.1.1 and XBB.1.5. A cocktail of TXG-0078 and CC24.2 provides protection against in vivo challenge with SARS-CoV-2, suggesting potential future use in variant-resistant therapeutic Ab cocktails and as templates for pan-coronavirus vaccine design.

Mining and analysis of the Big Data of Twitter conversations have been of significant interest to the scientific community in the fields of healthcare, epidemiology, big data, data science, computer science, and their related areas, as can be seen from several works in the last few years that focused on sentiment analysis and other forms of text analysis of Tweets related to Ebola, E-Coli, Dengue, Human papillomavirus (HPV), Middle East Respiratory Syndrome (MERS), Measles, Zika virus, H1N1, influenza-like illness, swine flu, flu, Cholera, Listeriosis, cancer, Liver Disease, Inflammatory Bowel Disease, kidney disease, lupus, Parkinson's, Diphtheria, and West Nile virus. The recent outbreaks of COVID-19 and MPox have served as "catalysts" for Twitter usage related to seeking and sharing information, views, opinions, and sentiments involving both these viruses. While there have been a few works published in the last few months that focused on performing sentiment analysis of Tweets related to either COVID-19 or MPox, none of the prior works in this field thus far involved analysis of Tweets focusing on both COVID-19 and MPox at the same time. With an aim to address this research gap, a total of 61,862 Tweets that focused on Mpox and COVID-19 simultaneously, posted between May 7, 2022, to March 3, 2023, were studied to perform sentiment analysis and text analysis. The findings of this study are manifold. First, the results of sentiment analysis show that almost half the Tweets (the actual percentage is 46.88%) had a negative sentiment. It was followed by Tweets that had a positive sentiment (31.97%) and Tweets that had a neutral sentiment (21.14%). Second, this paper presents the top 50 hashtags that were used in these Tweets. Third, it presents the top 100 most frequently used words that are featured in these Tweets. The findings of text analysis show that some of the commonly used words involved directly referring to either or both viruses. In addition to this, the presence of words such as "Polio", "Biden", "Ukraine", "HIV", "climate", and "Ebola" in the list of the top 100 most frequent words indicate that topics of conversations on Twitter in the context of COVID-19 and MPox also included a high level of interest related to other viruses, President Biden, and Ukraine. Finally, a comprehensive comparative study that involves a comparison of this work with 49 prior works in this field is presented to uphold the scientific contributions and relevance of the same.

Public health events (PHEs) have emerged as significant threats to human life and health, as well as affecting economic growth. PHEs such as COVID-19 have led people to reflect on better regular prevention and control (RPC) for PHEs. Firstly, under the background of RPC for PHEs, a neoclassical economic growth model is established from a long-term and macro perspective with the core concept of prevention and control intensity (PCI). Secondly, we obtain the equilibrium solution of the model, with the steady state and the balanced growth path analyzed. Additionally, an algorithm for optimal PCI and marginal propensity to consume (MPC) is given. Finally, the numerical simulation results demonstrate that this model has good interpretability to explore the mechanism of RPC for PHEs on economic growth, and can provide valuable guidance and policy recommendations of RPC for PHEs.

In 2016, in face of the Zika virus outbreak, research funding was made available to study the virus and the scientific community directed its resources correspondingly. This resulted in several publications and increased understanding of the infection, the virus, its vector, associated syndromes and mechanisms. Brazil was particularly affected by the outbreak and at the same time had a prominent position in the global scientific production about the outbreak.In this study, we aim to characterize the researchers who engaged with Zika research in Brazil and how funding policy mediated the redirection of research towards particular themes. We performed a bibliometric assessment of the authors in Brazil who worked on Zika as a case study of how individual scientists respond to major changes in the macro research agenda.Using data from Web of Science, PubMed and the Lattes platform, we investigated (1) the pattern of researcher’s “pivots”, i.e. changes in research direction due to the Zika outbreak and (2) the correspondence between funding mandates and the research output.Our results show that while authors engaged with Zika research coming from more apparently distant fields - such as neuroscience -, most of the authors who studied Zika came from the expected fields and themes - infectious diseases or public health. Using a MeSH term-based classification, we also analyzed the output of a particular grant with an specific research agenda, finding a partial correspondence between the funding mandate and the output produced by the grantees.The results obtained are an important addition to our understanding of how research funding can contribute to preparedness policy - a need made more obvious with the COVID-19 pandemic - while opening up new questions and ways of studying the downstream effects of funding policies on individual scientists’ choices of research paths.

SARS-CoV-2 infection during pregnancy is associated with severe COVID-19 and adverse fetal outcomes, but the underlying mechanisms remain poorly understood. Moreover, clinical studies assessing therapeutics against SARS-CoV-2 in pregnancy are limited. To address these gaps, we developed a mouse model of SARS-CoV-2 infection during pregnancy. Outbred CD1 mice were infected at embryonic day (E) 6, E10, or E16 with a mouse adapted SARS-CoV-2 (maSCV2) virus. Outcomes were gestational age-dependent, with greater morbidity, reduced anti-viral immunity, greater viral titers, and more adverse fetal outcomes occurring with infection at E16 (3 rd trimester-equivalent) than with infection at either E6 (1 st trimester-equivalent) or E10 (2 nd trimester-equivalent). To assess the efficacy of ritonavir-boosted nirmatrelvir (recommended for pregnant individuals with COVID-19), we treated E16-infected dams with mouse equivalent doses of nirmatrelvir and ritonavir. Treatment reduced pulmonary viral titers, decreased maternal morbidity, and prevented adverse offspring outcomes. Our results highlight that severe COVID-19 during pregnancy and adverse fetal outcomes are associated with heightened virus replication in maternal lungs. Ritonavir-boosted nirmatrelvir mitigated adverse maternal and fetal outcomes of SARS-CoV-2 infection. These findings prompt the need for further consideration of pregnancy in preclinical and clinical studies of therapeutics against viral infections.

Zika virus (ZIKV) is now in a post-pandemic period, for which the potential for re-emergence and future spread is unknown. Adding to this uncertainty is the unique capacity of ZIKV to directly transmit between humans via sexual transmission. Recently, we demonstrated that direct transmission of ZIKV between vertebrate hosts leads to rapid adaptation resulting in enhanced virulence in mice and the emergence of three amino acid substitutions (NS2A-A117V, NS2A- A117T, and NS4A-E19G) shared among all vertebrate-passaged lineages. Here, we further characterized these host-adapted viruses and found that vertebrate-passaged viruses also have enhanced transmission potential in mosquitoes. To understand the contribution of genetic changes to the enhanced virulence and transmission phenotype, we engineered these amino acid substitutions, singly and in combination, into a ZIKV infectious clone. We found that NS4A- E19G contributed to the enhanced virulence and mortality phenotype in mice. Further analyses revealed that NS4A-E19G results in increased neurotropism and distinct innate immune signaling patterns in the brain. None of the substitutions contributed to changes in transmission potential in mosquitoes. Together, these findings suggest that direct transmission chains could enable the emergence of more virulent ZIKV strains without compromising mosquito transmission capacity, although the underlying genetics of these adaptations are complex.

Background & Aims Human genetic variation is thought to guide the outcome of hepatitis C virus (HCV) infection but model systems within which to dissect these host genetic mechanisms are limited. Norway rat hepacivirus (NrHV), closely related to HCV, causes chronic liver infection in rats but causes acute self-limiting hepatitis in typical strains of laboratory mice, which resolves in two weeks. The Collaborative Cross (CC) is a robust mouse genetics resource comprised of a panel of recombinant inbred strains, which model the complexity of the human genome and provide a system within which to understand diseases driven by complex allelic variation. Approach & Results We infected a panel of CC strains with NrHV and identified several that failed to clear virus after 4 weeks. Strains displayed an array of virologic phenotypes ranging from delayed clearance (CC046) to chronicity (CC071, CC080) with viremia for at least 10 months. Body weight loss, hepatocyte infection frequency, viral evolution, T-cell recruitment to the liver, liver inflammation and the capacity to develop liver fibrosis varied among infected CC strains. Conclusions These models recapitulate many aspects of HCV infection in humans and demonstrate that host genetic variation affects a multitude of virus and host phenotypes. These models can be used to better understand the molecular mechanisms that drive hepacivirus clearance and chronicity, the virus and host interactions that promote chronic disease manifestations like liver fibrosis, therapeutic and vaccine performance, and how these factors are affected by host genetic variation.

The Supreme Court’s most recent term produced a number of blockbuster decisions, nearly hiding a federalism agenda that surfaced in health law, reproductive rights, administrative law, and other domains, weaving through cases where federalism was not obviously at issue, and appearing in “shadow docket” as well as regular decisions. Health laws have been front and center at the Court many times before now, and health care has been a vehicle for constitutional change in the past, but the New Roberts Court is raising the stakes for older health laws, most of which rely on states to achieve national goals. This article shows that the Court has increased formal interpretive methods that limit governmental power, like clear statement rules and the major questions doctrine, which are likely to have deregulatory impact across public laws. I claim a pattern is developing in which the New Roberts Court is centering a formal, separate-spheres vision of federalism that favors states’ rights, regardless of states’ capacity to wield that power or evidence that they do not. Law is a determinant of health, controlling access to individual medical care and public health. For most social programs, Congress relies on federalism, which divides power and responsibility for implementing policies across federal, state, and local governments. However, laws enacted before the Court’s “Federalism Revolution” in the 1990s, like the Medicaid Act, have no federal alternative (or “fallback”) if states refuse to participate. State capacity to exercise power allocated by federalism has been assumed by judges and theorists alike. Yet, the pandemic crystalized that the governance capacity assumption is out of step with actual practice, and that states can effectively veto federal laws that have no fallback. Additionally, the inherent variability federalism invites impacts health inequitably, especially for racial and ethnic minorities and other vulnerable populations like rural communities. This article spotlights the Court’s recent decisions using health law as a vehicle for constitutional change and probes theoretical assumptions about federalism’s values, illustrating the risks of these new patterns through two key examples, Medicaid expansion and the public health emergency for COVID-19. The article then identifies legal and ethical principles courts, administrative agencies, states, and policymakers could employ given that the Court is not likely to change course soon. Congress has authority to create new federal laws, or to amend laws, either of which would ironically increase federal power in states that will not partner. I also argue the traditional federalism values could and should be evaluated concretely using existing principles in law and bioethics as well as data from other disciplines. Many federal health laws are in danger of instability and dilution, but it may be possible to avert bad outcomes.

The SARS-CoV-2 pandemic has led to the emergence of various variants of concern (VoCs) that are associated with increased transmissibility, immune evasion, or differences in disease severity. The emergence of VoCs fueled interest in understanding the potential impact of travel restrictions and surveillance strategies to prevent or delay the early spread of VoCs. We performed phylogenetic analyses and mathematical modeling to study the importation and spread of the VoCs Alpha and Delta in Switzerland in 2020 and 2021. Using a phylogenetic approach, we estimated 383-1,038 imports of Alpha and 455-1,347 imports of Delta into Switzerland. We then used the results from the phylogenetic analysis to parameterize a dynamic transmission that accurately described the subsequent spread of Alpha and Delta. We modeled different counterfactual intervention scenarios to quantify the potential impact of border closures and surveillance of travelers on the spread of Alpha and Delta. We found that implementing border closures after the announcement of VoCs would have been of limited impact to mitigate the spread of VoCs. In contrast, increased surveillance of travelers could prove to be an effective measure for delaying the spread of VoCs in situations where their severity remains unclear. Our study shows how phylogenetic analysis in combination with dynamic transmission models can be used to estimate the number of imported SARS-CoV-2 variants and the potential impact of different intervention scenarios to inform the public health response during the pandemic.

Development of disposable, rapid and convenient biosensor with high sensitivity and reliability is the most desired method of viral disease prevention. To achieve this goal, in this work, a practical impedimetric biosensor has been implemented into a disposable electrode on a screen-printed carbon electrode (SPCE) for the detection of two mosquito-borne viruses. The biosensor fabrication has step-wisely carried out on the disposable electrode surface at room temperature: starting from conductive film formation, physical binding of the gold nanoparticles (AuNPs)-polyaniline (PAni) into the conductive film, and biofunctionalization. To get the maximum efficiency of the antibody, biotinylated antibody has been conjugated on the surface of AuNP-PAni /PAni-SPCE via the streptavidin-biotin conjugation method which is a critical factor for the high sensitivity. Using the antibody-antigen interaction, this disposable electrode has designed to detect mosquito-borne infectious viruses, Chikungunya virus (CHIKV) and Zika Virus (ZIKV) separately in a wide linear range of 100 fg/mL to 1 ng/mL with a low detection limit of 1.33 fg/mL and 12.31 fg/mL, respectively.

Aging is the primary risk factor for most neurodegenerative diseases, and recently coronavirus disease 2019 (COVID-19) has been associated with severe neurological manifestations that can eventually impact neurodegenerative conditions in the long-term. The progressive accumulation of senescent cells in vivo strongly contributes to brain aging and neurodegenerative co-morbidities but the impact of virus-induced senescence in the aetiology of neuropathologies is unknown. Here, we show that senescent cells accumulate in physiologically aged brain organoids of human origin and that senolytic treatment reduces inflammation and cellular senescence; for which we found that combined treatment with the senolytic drugs dasatinib and quercetin rejuvenates transcriptomic human brain aging clocks. We further interrogated brain frontal cortex regions in postmortem patients who succumbed to severe COVID-19 and observed increased accumulation of senescent cells as compared to age-matched control brains from non-COVID-affected individuals. Moreover, we show that exposure of human brain organoids to SARS-CoV-2 evoked cellular senescence, and that spatial transcriptomic sequencing of virus-induced senescent cells identified a unique SARS-CoV-2 variant-specific inflammatory signature that is different from endogenous naturally-emerging senescent cells. Importantly, following SARS-CoV-2 infection of human brain organoids, treatment with senolytics blocked viral retention and prevented the emergence of senescent corticothalamic and GABAergic neurons. Furthermore, we demonstrate in human ACE2 overexpressing mice that senolytic treatment ameliorates COVID-19 brain pathology following infection with SARS-CoV-2. In vivo treatment with senolytics improved SARS-CoV-2 clinical phenotype and survival, alleviated brain senescence and reactive astrogliosis, promoted survival of dopaminergic neurons, and reduced viral and senescence-associated secretory phenotype gene expression in the brain. Collectively, our findings demonstrate SARS-CoV-2 can trigger cellular senescence in the brain, and that senolytic therapy mitigates senescence-driven brain aging and multiple neuropathological sequelae caused by neurotropic viruses, including SARS-CoV-2.

Purpose: Transmission of infectious travel diseases is increasing, especially in travelers from developed to developing countries. Still, the incidence of many travel diseases is not known, because retrospective surveillance systems do not detect asymptomatic infections. Methods: : We took medical history and blood samples of 81 German travelers before and after travelling to South and Southeast Asia. IgG, IgM, and if possible IgA antibody titers were measured for Dengue virus (DENV), Chikungunya virus (CHIKV), Zika virus (ZIKV), Hepatitis E virus (HEV), and Camphylobacter jejuni (C.jejuni) using commercial ELISA kits. Additionally, we tested for Cytomegalovirus and Helicobacter pylori. Results: : No symptoms were reported. Still, we found one anti-ZIKV and two anti-DENV IgG seroconversions. For CHIKV, we found three individuals who were IgG-positive before travel and negative afterwards. We found five IgG seroconversions for C.jejuni and zero for HEV. We also found one IgG seroconversion for CMV, and zero for H.pylori. Calculated incidences were between zero and 6.5%. Conclusion: Using serological analyses, we found a small but significant number of travel infections that would have gone unnoticed by retrospectively asking for symptoms alone. This suggests that the risk for these infections may be higher than previously estimated.

The nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor that plays a critical role in the xenobiotic and stress responses. During viral infection, NRF2 can modulate the host metabolism and innate immunity; however, the most common activity of NRF2 in viral diseases is controlling reactive oxygen species (ROS). The Zika virus (ZIKV) is involved in a vertical infection in pregnancy, with reported fetal health consequences. However, the possibility that ZIKV regulates NRF2 expression in placental trophoblasts has not been investigated. In this report, we evaluated the upregulation of NRF2 and antioxidant enzymes in a trophoblast-like cell. These findings could help us understand the antioxidant mechanism underlying the ZIKV infection in the placenta during pregnancy.

Zika virus (ZIKV) can be transmitted vertically from mother to fetus during pregnancy, resulting in a range of outcomes, including severe birth defects and fetal/infant death. Potential pathways of vertical transmission in utero have been proposed but remain undefined. Identifying the timing and routes of vertical transmission of ZIKV may help us identify when interventions would be most effective. Furthermore, understanding what barriers ZIKV overcomes to effect vertical transmission may help improve models for evaluating infection by other pathogens during pregnancy. To determine the pathways of vertical transmission, we inoculated 12 pregnant rhesus macaques with an African-lineage ZIKV at gestational day 30 (term is 165 days). Eight pregnancies were surgically terminated at either seven or 14 days post-maternal infection. Maternal-fetal interface and fetal tissues and fluids were collected and evaluated with RT-qPCR, in situ hybridization for ZIKV RNA, immunohistochemistry, and plaque assays. Four additional pregnant macaques were inoculated and terminally perfused with 4% paraformaldehyde at three, six, nine, or ten days post-maternal inoculation. For these four cases, the entire fixed pregnant uterus was evaluated with in situ hybridization for ZIKV RNA. We determined that ZIKV can reach the MFI by six days post-infection and infect the fetus by ten days. Infection of the chorionic membrane and the extraembryonic coelomic fluid preceded infection of the fetus and the mesenchymal tissue of the placental villi. We did not find evidence to support a transplacental route of ZIKV vertical transmission via infection of syncytiotrophoblasts or villous cytotrophoblasts. The pattern of infection observed in the maternal-fetal interface provides evidence of vertical ZIKV transmission through the fetal membranes. Author’s Summary Zika virus (ZIKV) can be vertically transmitted from mother to fetus during pregnancy resulting in adverse pregnancy outcomes. For vertical transmission to occur, ZIKV must overcome the barriers of the maternal-fetal interface, yet the exact pathway ZIKV takes remains undefined. The maternal-fetal interface consists of the maternal decidua, the placenta, and the fetal membranes. ZIKV could reach the fetus through the placenta if it can infect the layer of cells that are directly exposed to maternal blood. ZIKV could also reach the fetus by infecting the decidua and then the adjacent fetal membranes. To determine the pathways of ZIKV vertical transmission, we infected pregnant macaques and evaluated ZIKV burden in the maternal-fetal interface and fetus shortly after maternal infection. The pattern of infection observed suggests that ZIKV vertically transmits through the fetal membranes, not the placenta. This finding is significant because it challenges the assumption that vertical transmission occurs exclusively across the placenta. By including the fetal membranes in our models of vertical transmission, we can more accurately determine which pathogens can be vertically transmitted. Ultimately, this study demonstrates that fetal membranes are an essential barrier to pathogens that warrant further investigation.

ABSTRACT With no therapeutics available, there is an urgent need to better understand the pathogenesis of flaviviruses which constitute a threat to public health worldwide. During infection, dengue virus (DENV) and Zika virus (ZIKV), two flaviviruses induce alterations of mitochondria morphology to favor viral replication, suggesting a viral co-opting of mitochondria functions. Here, we performed an extensive transmission electron microscopy-based quantitative analysis to demonstrate that both DENV and ZIKV alter endoplasmic reticulum-mitochondria contacts (ERMC). This correlated at the molecular level with an impairment of ERMC tethering protein complexes located at the surface of both organelles. Furthermore, virus infection, as well as NS4B expression modulated the mitochondrial oxygen consumption rate. Consistently, metabolomic and mitoproteomic analyses revealed a decrease in the abundance of several metabolites of the Krebs cycle and changes in the stoichiometry of the electron transport chain. Most importantly, ERMC destabilization by protein knockdown increased virus replication while dampening ZIKV-induced apoptosis. Overall, our results support the notion that flaviviruses hijack ERMCs to generate a cytoplasmic environment beneficial for sustained and efficient replication.

Background: Studies examining the association between in utero Zika virus (ZIKV) exposure and child neurodevelopmental outcomes have produced varied results limited by the absence of a comparison group. The present study aimed to assess the neurodevelopmental outcomes among a cohort of children born with normal head circumference from pregnant people enrolled in the Zika in Pregnancy in Honduras (ZIPH) cohort study between July and December 2016. Methods Enrollment of pregnant people was voluntary and occurred during their first prenatal visit at a health center in Tegucigalpa, with collection of venous blood. Children with the following characteristics were selected for the longitudinal follow-up study: normal birth head circumference, > 6 months of age, born at one of two hospitals in Tegucigalpa, and known in utero ZIKV exposure status. In utero exposure to ZIKV was defined as a positive prenatal ZIKV IgM and/or positive ZIKV RNA result at enrollment. The developmental evaluation included Spanish language versions of the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III) and the Ages & Stages Questionnaires: Social-Emotional, Second Edition (ASQ:SE-2). Results One hundred fifty-two children were assessed between May 2018 and March 2020. The mean age was 2.0 years, and > 93% had adequate anthropometric growth. Sixty children were exposed to ZIKV during pregnancy. BSID-III and ASQ:SE-2 were performed in 151 and 152 children, respectively. Forty-one children had a delay (< 85 composite score) in any of the BSID-III domains. There were no statistically significant differences between exposed and unexposed groups; however, children with in utero exposure to ZIKV had lower cognitive and language scores that persisted after adjusting for maternal age and education and after excluding children born preterm and low birth weight from the analysis. Assessment of socioemotional development showed that 92% of children had adequate development with a score equal to or below the cutoff point; there were no statistically significant differences between exposed and non-exposed children. Conclusions The exploration of cognitive and language differences in ZIKV exposed vs. non-exposed children could be informed by additional research in larger samples. Children with prenatal ZIKV exposure can be monitored for cognitive and language delays and referred for interventions as needed.