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1.
Adv Exp Med Biol ; 1451: 1-20, 2024.
Article in English | MEDLINE | ID: mdl-38801568

ABSTRACT

Monkeypox (Mpox) is a zoonotic disease caused by a virus (monkeypox virus-MPV) belonging to the Poxviridae family. In humans, the disease has an incubation period of 5-21 days and then progresses in two phases, the prodromal phase and the rash phase. The prodromal phase is characterized by non-specific symptoms such as fever, muscle pain, malaise, lymphadenopathy, headache, and chills. Skin lesions appear in the rash phase of the disease. These lesions progress through different stages (macules, papules, vesicles, and pustules). In May 2022, WHO reported an outbreak of human Mpox in several countries which were previously Mpox-free. As per the CDC report of March 01, 2023, a total of 86,231 confirmed cases of Mpox and 105 deaths have been reported from 110 countries and territories across the globe. Notably, more than 90% of these countries were reporting Mpox for the first time. The phylogenetic analysis revealed that this outbreak was associated with the virus from the West African clade. However, most of the cases in this outbreak had no evidence of travel histories to MPV-endemic countries in Central or West Africa. This outbreak was primarily driven by the transmission of the virus via intimate contact in men who have sex with men (MSM). The changing epidemiology of Mpox raised concerns about the increasing spread of the disease in non-endemic countries and the urgent need to control and prevent it. In this chapter, we present all the documented cases of Mpox from 1970 to 2023 and discuss the past, present, and future of MPV.


Subject(s)
Disease Outbreaks , Monkeypox virus , Mpox (monkeypox) , Animals , Humans , Monkeypox virus/genetics , Monkeypox virus/pathogenicity , Mpox (monkeypox)/epidemiology , Mpox (monkeypox)/transmission , Mpox (monkeypox)/virology , Phylogeny , Zoonoses/epidemiology , Zoonoses/virology , Zoonoses/transmission
2.
Rev Med Virol ; 34(1): e2489, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37930054

ABSTRACT

In May 2022, World Health Organization (WHO) reported an outbreak of Mpox in several European countries which were previously Mpox free. Mpox (formerly known as monkeypox) is a zoonotic viral disease endemic in Central and West Africa. The sudden emergence of Mpox outside Africa and its subsequent rapid spread lead the WHO to declare the outbreak as Public Health Emergency of International Concern. By 15 May 2023, a total of 87,704 confirmed cases and 140 deaths had been reported from 111 countries and territories worldwide. Looking back on this outbreak 1 year later, several important questions have arisen. Here, we address these questions using the classic 5 Ws: What, When, Where, Who and Why? We discuss these questions to understand how this outbreak emerged and how it was effectively managed. We outline what needs to be done to prevent, or at least minimise, outbreaks due to emerging and re-emerging viral infections.


Subject(s)
Mpox (monkeypox) , Humans , Animals , Mpox (monkeypox)/epidemiology , Disease Outbreaks , Zoonoses , Public Health , Africa/epidemiology
3.
Vaccines (Basel) ; 11(3)2023 Feb 24.
Article in English | MEDLINE | ID: mdl-36992124

ABSTRACT

Epstein-Barr virus (EBV) is etiologically associated with a number of malignant and non-malignant conditions. Thus, a prophylactic vaccine against this virus could help to reduce the burden of many EBV-associated diseases. Previously, we reported that an EBV virus-like particle (VLP) vaccine was highly immunogenic and produced a strong humoral response in mice. However, since EBV does not infect mice, the efficacy of the VLP in preventing EBV infection could not be addressed. Here we examined, for the first time, the efficacy of the EBV-VLP vaccine using a novel rabbit model of EBV infection. Animals vaccinated with two doses of VLP elicited higher antibody responses to total EBV antigens compared to animals receiving one dose. Vaccinated animals also elicited both IgM and IgG to EBV-specific antigens, VCA and EBNA1. Analysis of peripheral blood and spleen for EBV copy number indicated that the viral load in both of these compartments was lower in animals receiving a 2-dose vaccine. However, the VLP vaccine was ineffective in preventing EBV infection. With several other EBV vaccine candidates currently at various stages of development and testing, we believe that the rabbit model of EBV infection could be a great platform for evaluating potential candidates.

4.
Front Immunol ; 13: 1036155, 2022.
Article in English | MEDLINE | ID: mdl-36466898

ABSTRACT

Multiple sclerosis (MS) is a chronic disease of the central nervous system (CNS), marked primarily by demyelination, inflammation, and neurodegeneration. While the prevalence and incidence rates of MS are on the rise, the etiology of the disease remains enigmatic. Nevertheless, it is widely acknowledged that MS develops in persons who are both genetically predisposed and exposed to a certain set of environmental factors. One of the most plausible environmental culprits is Epstein-Barr virus (EBV), a common herpesvirus asymptomatically carried by more than 90% of the adult population. How EBV induces MS pathogenesis remains unknown. A comprehensive understanding of the biology of EBV infection and how it contributes to dysfunction of the immune system and CNS, requires an appreciation of the viral dynamics within the host. Here, we aim to outline the different animal models, including nonhuman primates (NHP), rodents, and rabbits, that have been used to elucidate the link between EBV and MS. This review particularly focuses on how the disruption in virus-immune interaction plays a role in viral pathogenesis and promotes neuroinflammation. We also summarize the effects of virus titers, age of animals, and route of inoculation on the neuroinvasiveness and neuropathogenic potential of the virus. Reviewing the rich data generated from these animal models could provide directions for future studies aimed to understand the mechanism(s) by which EBV induces MS pathology and insights for the development of prophylactic and therapeutic interventions that could ameliorate the disease.


Subject(s)
Epstein-Barr Virus Infections , Multiple Sclerosis , Animals , Rabbits , Herpesvirus 4, Human , Multiple Sclerosis/etiology , Epstein-Barr Virus Infections/complications , Serologic Tests , Models, Animal
5.
Viruses ; 14(11)2022 11 16.
Article in English | MEDLINE | ID: mdl-36423146

ABSTRACT

Epstein-Barr virus-encoded RNAs (EBERs) are two small, noncoding, structurally conserved transcripts, constitutively expressed at >106 copies per EBV-infected cell. They have been shown to drive cell growth. However, the mechanism(s) involved in EBER-induced proliferation is not clear. In this study, we investigated the molecular mechanisms and structural impact of EBER1. Sequences of EBER1 stem-loops (SL) 1, 3, and 4 were deleted, creating three mutants: ∆SL1, ∆SL3, and ∆SL4. These mutants were cloned into pHebo plasmids and expressed in Jurkat cell lines. Cells transfected with wildtype EBER1 and pHebo were used as controls. Cell proliferation was monitored by microscopy and flow cytometry. Microarray, qPCR, and Western blotting were used to investigate the cell cycle markers. We found significantly higher cell proliferation in wildtype EBER1 cells compared to pHebo, ∆SL1, and ∆SL3, but not ∆SL4 mutants. There was also significant upregulation of S-phase and G2/M phase markers in wildtype EBER1 and ∆SL4 mutant. Furthermore, CDT1, a factor for DNA replication, was upregulated in wildtype EBER1 and ∆SL4 mutant. However, in ∆SL1 mutant, CDT1 was significantly downregulated and translocated to the cytoplasm. These data indicate that the structure of EBER1 is important in cell proliferation.


Subject(s)
Epstein-Barr Virus Infections , Herpesvirus 4, Human , Humans , Herpesvirus 4, Human/genetics , Cell Proliferation , RNA, Untranslated/genetics
7.
Front Vet Sci ; 9: 938601, 2022.
Article in English | MEDLINE | ID: mdl-36176697

ABSTRACT

Crimean-Congo hemorrhagic fever (CCHF) is an important tick-borne viral infection with a fatality rate of up to 50% during outbreaks. Crimean-Congo hemorrhagic fever virus (CCHFV) is sustained in the ecosystem in benign form through vertical and horizontal transmission cycles involving tick vectors, wildlife, and livestock. Hyalomma ticks are considered the major source of human infection. CCHF occurs most often among butchers, slaughterhouse workers, and farmworkers through infected tick bites or/and contact with blood and tissues of infected livestock. The nosocomial transmission can occur in auxiliary nurses and physicians through contact with the infected patients. The widespread distribution of CCHFV most probably occurred by ticks on migratory birds, or through international travel and trade of livestock and wildlife. During co-infections of ticks and vertebrates, reassortment among genome segments could play a significant role in generating diversity, and hence, a potential risk for the emergence of novel variants. In this systematic review, we aimed to determine the epidemiology, transmission, distribution, mortality, and clinical features of CCHF in 22 Arab countries, comprising the Arab world. Based on the analysis of 57 studies published from 1978 to 2021, we found 20 tick species that could be associated with CCHFV transmission. During the 43-year period, 321 cases of CCHF were reported from 9/22 Arab countries, Iraq, Kuwait, UAE, Saudi Arabia, Oman, Sudan, Egypt, Tunisia, and Mauritania. The mean case fatality rate was 29% during various outbreaks. Individuals working in abattoirs/slaughter houses, livestock farms, and healthcare were most at risk. Contact with blood or body secretions from infected animals and patients was the most common mode of transmission. A number of different animals, including cattle, goats, sheep, and camels were reported to be seropositive for CCHFV. The highest seroprevalence was observed in camels (29%), followed by cattle (21%), goats (15%), and sheep (14%). We discuss these results in the context of policy-making and potential preventative measures that can be implemented to reduce the burden of CCHF in the Arab world.

8.
Front Med (Lausanne) ; 9: 871885, 2022.
Article in English | MEDLINE | ID: mdl-36111116

ABSTRACT

COVID-19 is a contagious disease that has infected over half a billion people worldwide. Due to the rapid spread of the virus, countries are facing challenges to cope with the infection growth. In particular, healthcare organizations face difficulties efficiently provisioning medical staff, equipment, hospital beds, and quarantine centers. Machine and deep learning models have been used to predict infections, but the selection of the model is challenging for a data analyst. This paper proposes an automated Artificial Intelligence-enabled proactive preparedness real-time system that selects a learning model based on the temporal distribution of the evolution of infection. The proposed system integrates a novel methodology in determining the suitable learning model, producing an accurate forecasting algorithm with no human intervention. Numerical experiments and comparative analysis were carried out between our proposed and state-of-the-art approaches. The results show that the proposed system predicts infections with 72.1% less Mean Absolute Percentage Error (MAPE) and 65.2% lower Root Mean Square Error (RMSE) on average than state-of-the-art approaches.

9.
J Infect Public Health ; 15(6): 609-614, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35537237

ABSTRACT

BACKGROUND: Despite substantial resources deployed to curb SARS-CoV-2 transmission, controlling the COVID-19 pandemic has been a major challenge. New variants of the virus are frequently emerging leading to new waves of infection and re-introduction of control measures. In this study, we assessed the effectiveness of containment strategies implemented in the early phase of the pandemic. METHODS: Real-world data for COVID-19 cases was retrieved for the period Jan 1 to May 1, 2020 from a number of different sources, including PubMed, MEDLINE, Facebook, Epidemic Forecasting and Google Mobility Reports. We analyzed data for 18 countries/regions that deployed containment strategies such as travel restrictions, lockdowns, stay-at-home requests, school/public events closure, social distancing, and exposure history information management (digital contact tracing, DCT). Primary outcome measure was the change in the number of new cases over 30 days before and after deployment of a control measure. We also compared the effectiveness of centralized versus decentralized DCT. Time series data for COVID-19 were analyzed using Mann-Kendall (M-K) trend tests to investigate the impact of these measures on changes in the number of new cases. The rate of change in the number of new cases was compared using M-K z-values and Sen's slope. RESULTS: In spite of the widespread implementation of conventional strategies such as lockdowns, travel restrictions, social distancing, school closures, and stay-at-home requests, analysis revealed that these measures could not prevent the spread of the virus. However, countries which adopted DCT with centralized data storage were more likely to contain the spread. CONCLUSIONS: Centralized DCT was more effective in containing the spread of COVID-19. Early implementation of centralized DCT should be considered in future outbreaks. However, challenges such as public acceptance, data security and privacy concerns will need to be addressed.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , COVID-19/epidemiology , COVID-19/prevention & control , Pandemics/prevention & control , Communicable Disease Control , Contact Tracing
10.
Gene Rep ; 26: 101505, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35071820

ABSTRACT

This review was focused on global data analysis and risk factors associated with morbidity and mortality of coronavirus disease 2019 from different countries, including Bangladesh, Brazil, China, Central Eastern Europe, Egypt, India, Iran, Pakistan, and South Asia, Africa, Turkey and UAE. Male showed higher confirmed and death cases compared to females in most of the countries. In addition, the case fatality ratio (CFR) for males was higher than for females. This gender variation in COVID-19 cases may be due to males' cultural activities, but similar variations in the number of COVID-19 affected males and females globally. Variations in the immune system can illustrate this divergent risk comparatively higher in males than females. The female immune system may have an edge to detect pathogens slightly earlier. In addition, women show comparatively higher innate and adaptive immune responses than men, which might be explained by the high density of immune-related genes in the X chromosome. Furthermore, SARS-CoV-2 viruses use angiotensin-converting enzyme 2 (ACE2) to enter the host cell, and men contain higher ACE2 than females. Therefore, males may be more vulnerable to COVID-19 than females. In addition, smoking habit also makes men susceptible to COVID-19. Considering the age-wise distribution, children and older adults were less infected than other age groups and the death rate. On the contrary, more death in the older group may be associated with less immune system function. In addition, most of these group have comorbidities like diabetes, high pressure, low lungs and kidney function, and other chronic diseases. Due to the substantial economic losses and the numerous infected people and deaths, research examining the features of the COVID-19 epidemic is essential to gain insight into mitigating its impact in the future and preparedness for any future epidemics.

11.
Methods ; 203: 276-281, 2022 07.
Article in English | MEDLINE | ID: mdl-33662563

ABSTRACT

Because of the outstanding contribution in genome editing, CRISPR has undoubtedly become the most popular technology around the world and two pioneers are awarded the Nobel Prize in Chemistry this year. Besides, along with the discovery of nonspecific trans-cleavage activities of several Cas proteins such as Cas12 and Cas13, many CRISPR-based molecular diagnostic systems have been successfully created, showing advantages in sensitivity, specificity and operation convenience. Among them, systems with Cas12, which targets DNA and trans-cleaves single-stranded DNA probes, are both simple and highly efficient. Here in this review, we mainly focus on the Cas12-based methods and briefly discuss their applications in nucleic acids detection and beyond.


Subject(s)
CRISPR-Cas Systems , Gene Editing , CRISPR-Cas Systems/genetics , DNA/genetics , DNA, Single-Stranded , Gene Editing/methods
12.
Pan Afr Med J ; 43: 129, 2022.
Article in English | MEDLINE | ID: mdl-36762166

ABSTRACT

The COVID-19 pandemic is arguably one of the greatest public health crises since the 1918 influenza pandemic. Although several vaccines have been approved and rolled out, effective antiviral treatment options are very limited. Here, we present a case of severe COVID-19 that failed to respond to the standard interventions and continued to deteriorate. On day 22 of his illness, after informed consent, the patient was administered 4000IU of erythropoietin (EPO) subcutaneously, in the hope of improving his O2 saturation. Positive response was observed in the patient within 24 hours. This prompted us to continued EPO treatment for a total of 42 days until full recovery and discharge. Our findings warrant further studies to ascertain the use of EPO in severe cases COVID-19.


Subject(s)
Antiviral Agents , COVID-19 , Erythropoietin , Humans , Antiviral Agents/therapeutic use , COVID-19/epidemiology , Erythropoietin/therapeutic use , SARS-CoV-2
13.
Front Immunol ; 12: 764937, 2021.
Article in English | MEDLINE | ID: mdl-34899715

ABSTRACT

Epstein-Barr virus (EBV) is a common herpesvirus associated with malignant and non-malignant conditions. An accumulating body of evidence supports a role for EBV in the pathogenesis of multiple sclerosis (MS), a demyelinating disease of the CNS. However, little is known about the details of the link between EBV and MS. One obstacle which has hindered research in this area has been the lack of a suitable animal model recapitulating natural infection in humans. We have recently shown that healthy rabbits are susceptible to EBV infection, and viral persistence in these animals mimics latent infection in humans. We used the rabbit model to investigate if peripheral EBV infection can lead to infection of the CNS and its potential consequences. We injected EBV intravenously in one group of animals, and phosphate-buffered saline (PBS) in another, with and without immunosuppression. Histopathological changes and viral dynamics were examined in peripheral blood, spleen, brain, and spinal cord, using a range of molecular and histopathology techniques. Our investigations uncovered important findings that could not be previously addressed. We showed that primary peripheral EBV infection can lead to the virus traversing the CNS. Cell associated, but not free virus in the plasma, correlated with CNS infection. The infected cells within the brain were found to be B-lymphocytes. Most notably, animals injected with EBV, but not PBS, developed inflammatory cellular aggregates in the CNS. The incidence of these aggregates increased in the immunosuppressed animals. The cellular aggregates contained compact clusters of macrophages surrounded by reactive astrocytes and dispersed B and T lymphocytes, but not myelinated nerve fibers. Moreover, studying EBV infection over a span of 28 days, revealed that the peak point for viral load in the periphery and CNS coincides with increased occurrence of cellular aggregates in the brain. Finally, peripheral EBV infection triggered temporal changes in the expression of latent viral transcripts and cytokines in the brain. The present study provides the first direct in vivo evidence for the role of peripheral EBV infection in CNS pathology, and highlights a unique model to dissect viral mechanisms contributing to the development of MS.


Subject(s)
Central Nervous System Diseases/pathology , Disease Models, Animal , Epstein-Barr Virus Infections/pathology , Multiple Sclerosis/pathology , Neuroinflammatory Diseases/pathology , Animals , Central Nervous System Diseases/immunology , Epstein-Barr Virus Infections/immunology , Multiple Sclerosis/immunology , Neuroinflammatory Diseases/immunology , Rabbits
14.
Pan Afr Med J ; 39: 244, 2021.
Article in English | MEDLINE | ID: mdl-34659617

ABSTRACT

Numerous genetic tests for the detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, including those based on the ever-popular real-time polymerase chain reaction (RT-qPCR) technique, have been reported. These diagnostic tests give false negatives particularly during the early and late stages of COVID-19 clearly indicating inadequate test sensitivity. The entire COVID-19 diagnostic workflow is often overlooked and given very little attention. Herein, we propose that volumetric modifications to COVID-19 workflows would significantly improve detection limits. We would therefore encourage researchers to adopt a holistic approach, in which all the steps of a COVID-19 diagnostic workflow, are carefully scrutinised, particularly those upstream factors at the viral sampling and pre-analytical stages.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , Real-Time Polymerase Chain Reaction/methods , COVID-19 Testing/standards , False Negative Reactions , Humans , Limit of Detection , Real-Time Polymerase Chain Reaction/standards , Sensitivity and Specificity , Specimen Handling
15.
Neural Comput Appl ; : 1-9, 2021 Oct 09.
Article in English | MEDLINE | ID: mdl-34658535

ABSTRACT

COVID-19 as a global pandemic has had an unprecedented impact on the entire world. Projecting the future spread of the virus in relation to its characteristics for a specific suite of countries against a temporal trend can provide public health guidance to governments and organizations. Therefore, this paper presented an epidemiological comparison of the traditional SEIR model with an extended and modified version of the same model by splitting the infected compartment into asymptomatic mild and symptomatic severe. We then exposed our derived layered model into two distinct case studies with variations in mitigation strategies and non-pharmaceutical interventions (NPIs) as a matter of benchmarking and comparison. We focused on exploring the United Arab Emirates (a small yet urban centre (where clear sequential stages NPIs were implemented). Further, we concentrated on extending the models by utilizing the effective reproductive number (R t) estimated against time, a more realistic than the static R 0, to assess the potential impact of NPIs within each case study. Compared to the traditional SEIR model, the results supported the modified model as being more sensitive in terms of peaks of simulated cases and flattening determinations.

16.
Cells ; 10(10)2021 09 24.
Article in English | MEDLINE | ID: mdl-34685515

ABSTRACT

Eukaryotic cells contain dynamic membrane-bound organelles that are constantly remodeled in response to physiological and environmental cues. Key organelles are the endoplasmic reticulum, the Golgi apparatus and the plasma membrane, which are interconnected by vesicular traffic through the secretory transport route. Numerous viruses, especially enveloped viruses, use and modify compartments of the secretory pathway to promote their replication, assembly and cell egression by hijacking the host cell machinery. In some cases, the subversion mechanism has been uncovered. In this review, we summarize our current understanding of how the secretory pathway is subverted and exploited by viruses belonging to Picornaviridae, Coronaviridae, Flaviviridae,Poxviridae, Parvoviridae and Herpesviridae families.


Subject(s)
Endoplasmic Reticulum/virology , Golgi Apparatus/virology , Secretory Pathway/physiology , Viruses/isolation & purification , Biological Transport/physiology , Cell Membrane/metabolism , Cell Membrane/virology , Endoplasmic Reticulum/metabolism , Golgi Apparatus/metabolism , Humans
17.
Sci Rep ; 11(1): 21220, 2021 10 27.
Article in English | MEDLINE | ID: mdl-34707156

ABSTRACT

Epstein-Barr virus (EBV) is an oncogenic herpesvirus implicated in the pathogenesis of several malignant and non-malignant conditions. However, a number of fundamental aspects about the biology of EBV and the mechanism(s) by which this virus induces pathology remain unknown. One major obstacle has been the lack of a suitable animal model for EBV infection. In this study, using our recently established rabbit model of EBV infection, we examined the early events following primary EBV infection. We show that, both immunocompetent and immunosuppressed animals were readily susceptible to EBV infection. However, immunosuppressed animals showed marked splenomegaly and widespread infection. Following EBV infection, the virus primarily targeted naïve IgM+, CD20+, CD21+ and CD79a+ B cells. Infected cells expressed varying sets of viral latent/lytic gene products. Notably, co-expression of latent and lytic proteins in the same cell was not observed. Infected cells in type 0/1 latency (EBERs+), were small and proliferating (Ki67+). By contrast, cells in type 2/3 latency (LMP1+), were large, non-proliferating (Ki-67-) and p53+. Although infected B-cells were widely present in splenic follicles, they did not express germinal center marker, BCL-6. Taken together, this study shows for the first time, some of the early events following primary EBV infection.


Subject(s)
Epstein-Barr Virus Infections/immunology , Germinal Center/immunology , Spleen/immunology , Animals , Antigens, CD20/metabolism , B-Lymphocytes/immunology , B-Lymphocytes/virology , CD79 Antigens/metabolism , Epstein-Barr Virus Infections/pathology , Germinal Center/virology , Immunoglobulin M/immunology , Ki-67 Antigen/metabolism , Proto-Oncogene Proteins c-bcl-6/metabolism , Rabbits , Receptors, Complement 3d/metabolism , Spleen/pathology , Spleen/virology , Tumor Suppressor Protein p53/metabolism
18.
Microbiol Spectr ; 9(2): e0073321, 2021 10 31.
Article in English | MEDLINE | ID: mdl-34585943

ABSTRACT

Serological assays for measuring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies have crucial applications in the control and surveillance of the current COVID-19 pandemic. A large number of such assays have been developed and are now commercially available. However, there are limited studies evaluating the performance of these tests. We evaluated the performances of the following six commercially available serological assays for detecting SARS-CoV-2 antibodies: (i) Genscript cPass surrogate virus neutralization test (Genscript cPass), (ii) Diasorin-SARS-CoV-2 S1/S2 IgG detection (Diasorin-S1/S2 IgG), (iii) Alinity SARS-CoV-2 IgG II (Alinity IgG II), (iv) Diasorin-SARS-CoV-2 TrimericS IgG (Diasorin-TrimericS IgG), (v) Roche Elecsys anti-SARS-CoV-2-cobas (Roche Elecsys), and (vi) AESKU enzyme linked immunosorbent assay (AESKULISA). The results of these tests were compared against the gold standard plaque reduction neutralization test (PRNT). Roche Elecsys had the highest sensitivity, and the Genscript cPass had the highest specificity. Diasorin-TrimericS IgG had the best overall performance with the highest agreement with the PRNT results. Parallel testing of Genscript cPass with Diasorin-TrimericS IgG and Diasorin-S1/S2 IgG had the optimum performance. Based on the receiver operating characteristic (ROC) curve, lowering the cutoff from 30% to 20% in the Genscript cPass significantly increased the sensitivity and the overall agreement with the PRNT results. Commercially available serological assays are good alternatives to the standard PRNT. However, further studies on larger sample numbers are required for optimization of the assay cutoff values and for evaluation of cost effectiveness. IMPORTANCE Commercial serological assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are now widely available. This study adds new knowledge regarding the optimization of these assays for evaluating postvaccination antibodies status. It highlights the positive and negative aspects of each assay in terms of sensitivity, specificity, and positive and negative predictive values, compared to the gold standard neutralization test. When using serological assays to assess postvaccine immune status, a balance of all parameters needs to be considered and not simply the high specificity. This balance is particularly relevant in the current situation where countries are aiming to mass vaccinate their populations and bring this pandemic under control. Assays with good sensitivity will have a lower percentage of false negatives and thus provide confidence for vaccination. Understanding the strengths and limitations of commercially available serological assays is important, not only for better application of these tests but also to understand the immune response and the duration of protection postvaccination.


Subject(s)
Antibodies, Viral/blood , COVID-19 Serological Testing/methods , COVID-19 Vaccines/immunology , COVID-19/prevention & control , SARS-CoV-2/immunology , Adolescent , Adult , Aged , COVID-19/immunology , Coronavirus Nucleocapsid Proteins/immunology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Middle Aged , Phosphoproteins/immunology , Spike Glycoprotein, Coronavirus/immunology , Vaccines, Inactivated/immunology , Young Adult
19.
Virus Res ; 305: 198550, 2021 11.
Article in English | MEDLINE | ID: mdl-34454973

ABSTRACT

Epstein-Barr virus encoded RNAs (EBER1 and EBER2) are two non-polyadenylated, non-protein coding small RNAs expressed at high levels in all forms of EBV latent infections. Although not directly involved in cell transformation, a number of studies have reported that these RNAs may be involved in cell proliferation. However, which of the two EBERs play a major role in this process and the mechanisms involved remains unknown. The aim of this study was to investigate the role and mechanism of EBER1-induced cell proliferation. Using stably transfected EBER1 cell lines, and multiple methodologies, we show that EBER1 transfected epithelial, B and T cell lines proliferate at a higher rate, have higher metabolic activity and increased DNA synthesis. The mitochondrial number and activity was also observed to be higher in the EBER1 transfected cells. Moreover, cytochrome c activity and store operated calcium entry (SOCE) were potentiated in the EBER1 expressing cells. Finally, the genes associated with cell proliferation were also observed to be up-regulated in the EBER1 transfected cells. Taken together, our data has unravelled the role of mitochondria and cellular calcium pathway that appear to be involved in EBER1 induced cell proliferation of EBV infected cells.


Subject(s)
Epstein-Barr Virus Infections , Herpesvirus 4, Human , Calcium , Cell Proliferation , Epstein-Barr Virus Infections/genetics , Herpesvirus 4, Human/metabolism , Humans , RNA, Viral/genetics
20.
J Epidemiol Glob Health ; 11(3): 296-301, 2021 09.
Article in English | MEDLINE | ID: mdl-34270183

ABSTRACT

We aimed to assess global trends in Human Immunodeficiency Virus (HIV)/Acquired Immune Deficiency Syndrome (AIDS) and evaluate progress toward eradication since the inception of the pandemic. Data were extracted from the Global Burden of Disease 2019 update and the UNAIDS Data 2019. The datasets included annual figures from 1990 to 2019 for HIV/AIDS in 204 countries and all world regions. We analyzed rates and trends for prevalence, incidence, mortality and disability adjusted life years. Analysis of age and gender distribution in different regions was used to assess demographic changes. Forecasting was used to estimate disease burden up to 2040. Although many countries have witnessed a decrease in the incidence, for Russia, Ukraine, Portugal, Brazil, Spain and the United States, the rates of new cases are rising since 2010. This trend is present even in age-standardized analysis, indicating a rise in excess of population growth. Over 0.5% of the world's population is infected. About 5000 new infections occur daily, of which 500 are children. Mortality rates are falling globally; currently at 11 deaths per 100,000 population, forecasted to decrease to 8.5 deaths by 2040. Prevalence continues to increase, with South Africa, Nigeria, Mozambique, India, Kenya and the United States having the highest burden. The total number as well as the rates of new HIV infections are rising every year in Europe, South America, North America and other regions over the last decade. Maternal-to-child transmission continues at high rates despite effective preventive regimens. There is an urgent need to develop programs to curb the rising incidence of HIV.


Subject(s)
Acquired Immunodeficiency Syndrome , HIV Infections , Acquired Immunodeficiency Syndrome/epidemiology , Brazil , Europe/epidemiology , HIV Infections/epidemiology , Humans , North America/epidemiology
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