First detection of Bandavirus dabieense in ticks collected from migratory birds in the Republic of Korea

The causative agent of severe fever with thrombocytopenia syndrome (SFTS) is Bandavirus dabieense, an emerging tick-borne zoonotic pathogen. Migratory birds have often been suggested as potential carriers of ticks that can transmit Bandavirus dabieense; however, their role remains unclear. The Republic of Korea (ROK) holds an important position as a stopover on the East Asian-Australasian Flyway. The present study aimed to investigate the potential involvement of migratory birds in the transmission of the SFTS virus (SFTSV) in the ROK. A total of 4,497 ticks were collected across various regions, including Heuksando and Daecheongdo, in the ROK, from bird migration seasons in 2022 and 2023. Genetic analysis of the SFTSV was performed for 96 ticks collected from 20 different species of migratory birds. Polymerase chain reaction (PCR) fragments of SFTSV were detected in one Haemaphysalis concinna nymph collected from a Black-faced Bunting (Emberiza spodocephala) and one Ixodes turdus nymph collected from an Olive-backed Pipit (Anthus hodgsoni) on Daecheongdo and Heuksando, respectively, during their northward migration in two spring seasons. This finding suggests that migratory birds can be considered as possible carriers and long-distance dispersers of ticks and associated tick-borne diseases. This study highlights the importance of clarifying the role and impact of migratory birds in the rapid expansion of tick-borne diseases, facilitating enhanced preparedness and the development of mitigation measures against emerging SFTS across and beyond East Asia.

Molecular epidemiology of hepatitis B virus (HBV) in Ethiopia: A review article

Hepatitis B virus (HBV) belongs to the family Hepadnaviridae and is the smallest human DNA virus, with a genome that is only 3200 nucleotides long. The absence of proofreading function in HBV reverse transcriptase provides a wide range of genetic variants for targeted outgrowth at different stages of infection. A number of sub genotypes and ten HBV genotypes (A through J) have been identified through analyses of the divergence of HBV genomic sequences. Numerous clinical outcomes, including the emergence of chronicity, the course of the disease, the effectiveness of treatment, and the response to vaccination, have been related to differences in genotype between HBV isolates. There are just seven studies that have been done in Ethiopia that examine the molecular epidemiology of HBV. Moreover, these studies haven't been compiled and reviewed yet. In this review, we looked at the genetic diversity and molecular epidemiology of HBV, the relationship between HBV genotypes and clinical outcomes, the immunopathogenesis of HBV, and finally the molecular epidemiology of HBV in Ethiopia. PubMed, Embase, and Google Scholar search engines were used to find relevant articles for the review. By using HBV genotyping, clinicians can better tailor vaccination decisions and antiviral therapy for patients with chronic hepatitis B who are more likely to experience the disease's progression.

Predictive models for functional cure in patients with CHB receiving PEG-IFN therapy based on HBsAg quantification through meta-analysis

BACKGROUND AND AIMS

The efficacy of achieving HBsAg clearance through pegylated interferon (PEG-IFNα) therapy in patients with chronic hepatitis B (CHB) remains uncertain, especially regarding the probability of achieving functional cure among patients with varying baseline HBsAg levels. We aimed to investigate the predictive value of HBsAg quantification for HBsAg seroclearance in CHB patients undergoing PEG-IFNα treatment.

METHODS

A systematic search was conducted in PubMed, Embase, and the Cochrane Library up to January 11, 2022. Subgroup analyses were performed for HBeAg-positive and HBeAg-negative patients, PEG-IFNα monotherapy and PEG-IFNα combination therapy, treatment-naive and treatment-experienced patients, and patients with or without liver cirrhosis.

RESULTS

This predictive model incorporated 102 studies. The overall HBsAg clearance rates at the end of treatment (EOT) and the end of follow-up (EOF) were 10.6% (95% CI 7.8-13.7%) and 11.1% (95% CI 8.4-14.1%), respectively. Baseline HBsAg quantification was the most significant factor. According to the model, it is projected that when baseline HBsAg levels are 100, 500, 1500, and 10,000 IU/ml, the HBsAg clearance rates at EOF could reach 53.9% (95% CI 40.4-66.8%), 32.1% (95% CI 24.8-38.7%), 14.2% (95% CI 9.8-18.8%), and 7.9% (95% CI 4.2-11.8%), respectively. Additionally, treatment-experienced patients with HBeAg-negative status, and without liver cirrhosis exhibited higher HBsAg clearance rates after PEG-IFNα treatment.

CONCLUSION

A successful predictive model has been established to predict the achievement of functional cure in CHB patients receiving PEG-IFNα therapy.

Deciphering the evolutionary landscape of severe fever with thrombocytopenia syndrome virus across East Asia

Severe fever with thrombocytopenia syndrome virus (SFTSV) poses a significant public health challenge in East Asia, necessitating a deeper understanding of its evolutionary dynamics to effectively manage its spread and pathogenicity. This study provides a comprehensive analysis of the genetic diversity, recombination patterns, and selection pressures across the SFTSV genome, utilizing an extensive dataset of 2041 sequences from various hosts and regions up to November 2023. Employing maximum likelihood and Bayesian evolutionary analysis by sampling trees (BEAST), we elucidated the phylogenetic relationships among nine distinct SFTSV genotypes (A, B1, B2, B3, B4, C, D, E, and F), revealing intricate patterns of viral evolution and genotype distribution across China, South Korea, and Japan. Furthermore, our analysis identified 34 potential reassortments, underscoring a dynamic genetic interplay among SFTSV strains. Genetic recombination was observed most frequently in the large segment and least in the small segment, with notable recombination hotspots characterized by stem-loop hairpin structures, indicative of a structural propensity for genetic recombination. Additionally, selection pressure analysis on critical viral genes indicated a predominant trend of negative selection, with specific sites within the RNA-dependent RNA polymerase and glycoprotein genes showing positive selection. These sites suggest evolutionary adaptations to host immune responses and environmental pressures. This study sheds light on the intricate evolutionary mechanisms shaping SFTSV, offering insights into its adaptive strategies and potential implications for vaccine development and therapeutic interventions.

Prevalence, Isolation, and Molecular Characterizationof Severe Fever with Thrombocytopenia Syndrome Virus in Cattle from the Republic of Korea

Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease caused by Bandavirus dabieense. Initially identified in China, this disease has spread throughout Asian countries via tick bites and animal-to-human transmission. However, reports of the prevalence of SFTS virus (SFTSV) in cattle in Korea are lacking. This study aimed to investigate SFTSV infections in grazing cattle in the Republic of Korea (ROK). Materials and Methods: In total, 845 grazing cattle serum samples were collected over 2 years (2019 and 2020) in the ROK, and viral RNA was extracted using a kit. One-step RT-nested PCR was performed to amplify the S-segment of SFTSV. Positive serum samples were used to isolate SFTSV in Vero E6 cells, and the full sequences were analyzed. A phylogenetic tree was constructed using the maximum-likelihood method with MEGA X. In addition, immunoglobulin G antibodies against SFTSV were investigated using an enzyme-linked immunosorbent assay. Results: Here, 4.0% of serum samples (34/845) were positive for SFTSV S-segments, and one virus isolate was cultured in Vero E6 cells. Phylogenetic analysis based on the partial S-segment classified 4 SFTSV isolates as the B-2 genotype, 9 as the B-3 genotype, 18 as an unclassified B genotype, and 3 as the D genotype. One cultured virus was classified as the B-2 genotype based on SFTSV L-, M-, and S-segments. Antibody detection results showed that 21.1% of serum samples (161/763) were positive for SFTSV. Conclusion: To the best of our knowledge, this is the first study performed to identify the prevalence of SFTSV in grazing cattle in the ROK. Our findings indicate the necessity for more intensive and continuous SFTSV monitoring, not only in cattle but also in other animals, to comprehend the genetic diversity of the virus and its potential eco-epidemiological impact on human health.

Molecular Characterization of Hepatitis B Virus in People Living with HIV in Rural and Peri-Urban Communities in Botswana

(1) Background: Hepatitis B virus (HBV) sequencing data are important for monitoring HBV evolution. We aimed to molecularly characterize HBV sequences from participants with HBV surface antigen-positive (HBsAg+) serology and occult hepatitis B infection (OBI+). (2) Methods: We utilized archived plasma samples from people living with human immunodeficiency virus (PLWH) in Botswana. HBV DNA was sequenced, genotyped and analyzed for mutations. We compared mutations from study sequences to those from previously generated HBV sequences in Botswana. The impact of OBI-associated mutations on protein function was assessed using the Protein Variation Effect Analyzer. (3) Results: Sequencing success was higher in HBsAg+ than in OBI+ samples [86/128 (67.2%) vs. 21/71 (29.2%)]. Overall, 93.5% (100/107) of sequences were genotype A1, 2.8% (3/107) were D3 and 3.7% (4/107) were E. We identified 13 escape mutations in 18/90 (20%) sequences with HBsAg coverage, with K122R having the highest frequency. The mutational profile of current sequences differed from previous Botswana HBV sequences, suggesting possible mutational changes over time. Mutations deemed to have an impact on protein function were tpQ6H, surfaceV194A and preCW28L. (4) Conclusions: We characterized HBV sequences from PLWH in Botswana. Escape mutations were prevalent and were not associated with OBI. Longitudinal HBV studies are needed to investigate HBV natural evolution.

Quantitative HBV Core Antibodies as a Prognostic Marker for HBeAg Seroclearance: A Systematic Review with Meta-Analysis

During chronic hepatitis B virus (HBV) infection, the seroclearance of hepatitis B e antigen (HBeAg) is an important event and a significant surrogate endpoint of all current therapeutic strategies. The prediction of HBeAg seroclearance can help assess the benefits of therapy in patients during or before therapy initiation. The quantitation of HBV core antibodies (qAnti-HBc) is a new non-invasive biomarker for solving multiple diagnostic dilemmas. A systematic review and meta-analysis of studies that measured qAnti-HBc in patients who achieved HBeAg seroclearance were performed through PubMed, Web of Science (WoS) and SCOPUS electronic database searches. Nineteen articles were included in the systematic review, comprising 3434 chronically infected patients (1014 with and 2420 without HBeAg seroclearance). Sixteen publications with data regarding qAnti-HBc levels were included in the meta-analysis. The baseline level of qAnti-HBc antibodies was significantly higher in patients with than without HBeAg seroclearance (SMD = 0.88, 95%CI SMD = 0.56-1.2, p < 0.001). The same conclusion was reached for patients originating from Asia (SMD = 0.94, 95%CI SMD = 0.55-1.33) and for the qAnti-HBc antibodies among adult HBV patients with therapy-induced HBeAg seroclearance (SMD = 0.90, 95%CI SMD = 0.54-1.25, p < 0.001). The systematic review and meta-analysis provide evidence of the role of qAnti-HBc as a promising biomarker for predicting HBeAg seroclearance in chronically infected patients.

Systematic review and meta-analysis: de novo combination of nucleos(t)ide analogs and pegylated interferon alpha versus pegylated interferon alpha monotherapy for the functional cure of chronic hepatitis B

Introduction: Chronic hepatitis B (CHB) is a worldwide infectious disease caused by hepatitis B virus (HBV). Optimizing antiviral treatment strategies could improve the functional cure (FC) rate of patients with CHB. This study aims to systematically review the FC rate of the de novo combination of nucleos(t)ide analogs (NAs) and pegylated interferon α (PEG-IFNα) versus that of PEG-IFNα monotherapy for CHB. Methods: Databases were searched until 31 December 2023. Selected studies included randomized controlled trials on the de novo combination of NAs and PEG-IFNα versus PEG-IFNα monotherapy for 48 weeks in patients with CHB to achieve FC, which was defined as hepatitis B surface antigen (HBsAg) loss and/or HBsAg seroconversion. Meta-analysis was conducted in accordance with the efficacy at the end of treatment and different time points during follow-up. Results: A total of 10 studies, encompassing 2,339 patients in total, were included. Subgroup analysis was conducted in accordance with whether first-line NAs were used. It found no statistically significant difference between HBsAg loss and HBsAg seroconversion at the end of treatment. Serum HBV DNA <500 copies/mL significantly differed between the two groups at the end of treatment and did not significantly differ during follow-up. Meanwhile, HBsAg loss and HBsAg seroconversion showed statistically significant differences at 24 weeks of follow-up. By contrast, no statistically significant difference was found in HBsAg loss at 48 weeks of follow-up. Discussion: Without distinguishing the eligible preponderant population, the efficacy of the de novo combination of NAs and PEG-IFNα in treating patients with CHB was not superior to that of PEG-IFNα monotherapy. Systematic Review Registration: PROSPERO, identifier CRD42022325239.

Serum dithiothreitol-oxidizing capacity (DOC) is a promising biomarker for excluding significant liver fibrosis: a proof-of-concept study

BACKGROUND

APRI and FIB-4 scores are used to exclude clinically significant fibrosis (defined as stage ≥ F2) in patients with chronic viral hepatitis. However, the cut-offs for these scores (generated by Youden indices) vary between different patient cohorts. This study aimed to evaluate whether serum dithiothreitol-oxidizing capacity (DOC), i.e., a surrogate test of quiescin sulfhydryl oxidase-1, which is a matrix remodeling enzyme, could be used to non-invasively identify significant fibrosis in patients with various chronic liver diseases (CLDs).

METHODS

Diagnostic performance of DOC was compared with APRI and FIB-4 for identifying significant fibrosis. ROC curve analyses were undertaken in: a) two chronic hepatitis B (CHB) cohorts, independently established from hospitals in Wenzhou (n = 208) and Hefei (n = 120); b) a MASLD cohort from Wenzhou hospital (n = 122); and c) a cohort with multiple CLD etiologies (except CHB and MASLD; n = 102), which was identified from patients in both hospitals. Cut-offs were calculated using the Youden index. All CLD patients (n = 552) were then stratified by age for ROC curve analyses and cut-off calculations.

RESULTS

Stratified by CLD etiology or age, ROC curve analyses consistently showed that the DOC test was superior to APRI and FIB-4 for discriminating between clinically significant fibrosis and no fibrosis, when APRI and FIB-4 showed poor/modest diagnostic performance (P < 0.05, P < 0.01 and P < 0.001 in 3, 1 and 3 cohort comparisons, respectively). Conversely, the DOC test was equivalent to APRI and FIB-4 when all tests showed moderate/adequate diagnostic performances (P > 0.05 in 11 cohort comparisons). DOC had a significant advantage over APRI or FIB-4 scores for establishing a uniform cut-off independently of age and CLD etiology (coefficients of variation of DOC, APRI and FIB-4 cut-offs were 1.7%, 22.9% and 47.6% in cohorts stratified by CLD etiology, 2.0%, 26.7% and 29.5% in cohorts stratified by age, respectively). The uniform cut-off was 2.13, yielded from all patients examined. Surprisingly, the uniform cut-off was the same as the DOC upper limit of normal with a specificity of 99%, estimated from 275 healthy control individuals. Hence, the uniform cut-off should possess a high negative predictive value for excluding significant fibrosis in primary care settings. A high DOC cut-off with 97.5% specificity could be used for detecting significant fibrosis (≥ F2) with an acceptable positive predictive value (87.1%).

CONCLUSIONS

This proof-of-concept study suggests that the DOC test may efficiently rule out and rule in significant liver fibrosis, thereby reducing the numbers of unnecessary liver biopsies. Moreover, the DOC test may be helpful for clinicians to exclude significant liver fibrosis in the general population.

Global epidemiology of severe fever with thrombocytopenia syndrome virus in human and animals: a systematic review and meta-analysis

Background

Since the initial identification of the Severe Fever with Thrombocytopenia Syndrome (SFTS) in ticks in rural areas of China in 2009, the virus has been increasingly isolated from a diverse array of hosts globally, exhibiting a rising trend in incidence. This study aims to conduct a systematic analysis of the temporal and spatial distribution of SFTS cases, alongside an examination of the infection rates across various hosts, with the objective of addressing public concerns regarding the spread and impact of the disease.

Methods

In this systematic review and meta-analysis, an exhaustive search was conducted across multiple databases, including PubMed, Web of Science, Embase, and Medline, CNKI, WanFang, and CQVIP. The literature search was confined to publications released between January 1, 2009, and May 29, 2023. The study focused on collating data pertaining to animal infections under natural conditions and human infection cases reported. Additionally, species names were unified using the National Center for Biotechnology Information (NCBI) database. The notification rate, notification death rate, case fatality rate, and infection rates (or MIR) were assessed for each study with available data. The proportions were pooled using a generalized linear mixed-effects model (GLMM). Meta-regressions were conducted for subgroup analysis. This research has been duly registered with PROSPERO, bearing the registration number CRD42023431010.

Findings

We identified 5492 studies from database searches and assessed 238 full-text studies for eligibility, of which 234 studies were included in the meta-analysis. For human infection data, the overall pooled notification rate was 18.93 (95% CI 17.02-21.05) per ten million people, the overall pooled notification deaths rate was 3.49 (95% CI 2.97-4.10) per ten million people, and the overall pooled case fatality rate was 7.80% (95% CI 7.01%-8.69%). There was an increasing trend in notification rate and deaths rate, while the case fatality rate showed a significant decrease globally. Regarding animal infection data, among 94 species tested, 48 species were found to carry positive nucleic acid or antibodies. Out of these, 14 species were classified under Arthropoda, while 34 species fell under Chordata, comprising 27 Mammalia and 7 Aves.

Interpretation

This systematic review and meta-analysis present the latest global report on SFTS. In terms of human infections, notification rates and notification deaths rates are on the rise, while the case fatality rate has significantly decreased. More SFTSV animal hosts have been discovered than before, particularly among birds, indicating a potentially broader transmission range for SFTSV. These findings provide crucial insights for the prevention and control of SFTS on a global scale.

Funding

None.

Occult hepatitis B virus infection and current perspectives on global WHO 2030 eradication

The current World Health Organization (WHO) Hepatitis Elimination Strategy suffers from lack of a target for diagnosing or expunging occult HBV infection. A sizable segment of the global population has an undetected HBV infection, particularly the high-risk populations and those residing in countries like India with intermediate endemicity. There is growing proof that people with hidden HBV infection can infect others, and that these infections are linked to serious chronic hepatic complications, especially hepatocellular carcinoma. Given the current diagnostic infrastructure in low-resource settings, the WHO 2030 objective of obliterating hepatitis B appears to be undeniably challenging to accomplish. Given the molecular basis of occult HBV infection strongly linked to intrahepatic persistence, patients may inexplicably harbour HBV genomes for a prolonged duration without displaying any pronounced clinical or biochemical signs of liver disease, and present histological signs of moderate degree necro-inflammation, diffuse fibrosis, and hence the international strategy to eradicate viral hepatitis warrants inclusion of occult HBV infection.

Reemergence of Clade IIb-Associated Mpox, Germany, July-December 2023

In July 2023, clade IIb-associated mpox reemerged in Germany at low levels, mainly affecting men who have sex with men. We report a representative case and phylogeny of available genome sequences. Our findings underscore the need for standardized surveillance and indication-based vaccination to limit transmission and help prevent endemicity.

A systematic mutation analysis of 13 major SARS-CoV-2 variants

SARS-CoV-2 evolves constantly with various novel mutations. Due to their enhanced infectivity, transmissibility and immune evasion, a comprehensive understanding of the association between these mutations and the respective functional changes is crucial. However, previous mutation studies of major SARS-CoV-2 variants remain limited. Here, we performed systematic analyses of full-length amino acids mutation, phylogenetic features, protein physicochemical properties, molecular dynamics and immune escape as well as pseudotype virus infection assays among thirteen major SARS-CoV-2 variants. We found that Omicron exhibited the most abundant and complex mutation sites, higher indices of hydrophobicity and flexibility than other variants. The results of molecular dynamics simulation suggest that Omicron has the highest number of hydrogen bonds and strongest binding free energy between the S protein and ACE2 receptor. Furthermore, we revealed 10 immune escape sites in 13 major variants, some of them were reported previously, but four of which (i.e. 339/373/477/496) are first reported to be specific to Omicron, whereas 462 is specific to Epslion. The infectivity of these variants was confirmed by the pseudotype virus infection assays. Our findings may help us understand the functional consequences of the mutations within various variants and the underlying mechanisms of the immune escapes conferred by the S proteins.

Exploring the efficacy of routine antimicrobial therapy in severe fever with thrombocytopenia syndrome: Overlap weighting analysis using a nationwide inpatient database

BACKGROUND

Severe fever with thrombocytopenia syndrome (SFTS) is an infectious disease that presents a formidable challenge due to the absence of established therapeutic strategies that are explicitly tailored to its management. This study aimed to assess the impact of routine antimicrobial therapy on patients diagnosed with SFTS in Japan. We conducted a comprehensive retrospective cohort analysis using extensive data from a national inpatient database.

METHODS

This study scrutinized data from adult patients with SFTS and categorized them based on whether they received antimicrobial treatment within the initial 2 days of hospital admission. A meticulous evaluation was carried out on a range of outcomes, such as in-hospital mortality rates, overall costs associated with hospitalization, and length of hospital stay. Overlap weighting was applied along with multivariate regression models to enhance the reliability of the findings through confounder adjustment. The outcomes showed no significant improvement in the prognosis of patients with SFTS who received routine antimicrobial therapy. The use of antimicrobials did not yield statistically significant improvements in in-hospital mortality rates or other secondary outcomes, suggesting that such therapeutic interventions may not be necessary during the early stages of hospital admission.

CONCLUSION

In our study, administration of antimicrobials within 2 days of admission for SFTS did not affect prognosis. The standard use of antimicrobial treatments may be an issue that should be reconsidered.

Alpha and gamma mangostins inhibit wild-type B SARS-CoV-2 more effectively than the SARS-CoV-2 variants and the major target is unlikely the 3C-like protease

Background

Anti-SARS-CoV-2 and immunomodulatory drugs are important for treating clinically severe patients with respiratory distress symptoms. Alpha- and gamma-mangostins (AM and GM) were previously reported as potential 3C-like protease (3CLpro) and Angiotensin-converting enzyme receptor 2 (ACE2)-binding inhibitors in silico.

Objective

We aimed to evaluate two active compounds, AM and GM, from Garcinia mangostana for their antivirals against SARS-CoV-2 in live virus culture systems and their cytotoxicities using standard methods. Also, we aimed to prove whether 3CLpro and ACE2 neutralization were major targets and explored whether any additional targets existed.

Methods

We tested the translation and replication efficiencies of SARS-CoV-2 in the presence of AM and GM. Initial and subgenomic translations were evaluated by immunofluorescence of SARS-CoV-2 3CLpro and N expressions at 16 h after infection. The viral genome was quantified and compared with the untreated group. We also evaluated the efficacies and cytotoxicities of AM and GM against four strains of SARS-CoV-2 (wild-type B, B.1.167.2, B.1.36.16, and B.1.1.529) in Vero E6 cells. The potential targets were evaluated using cell-based anti-attachment, time-of-drug addition, in vitro 3CLpro activities, and ACE2-binding using a surrogated viral neutralization test (sVNT). Moreover, additional targets were explored using combinatorial network-based interactions and Chemical Similarity Ensemble Approach (SEA).

Results

AM and GM reduced SARS-CoV-2 3CLpro and N expressions, suggesting that initial and subgenomic translations were globally inhibited. AM and GM inhibited all strains of SARS-CoV-2 at EC50 of 0.70-3.05 μM, in which wild-type B was the most susceptible strain (EC50 0.70-0.79 μM). AM was slightly more efficient in the variants (EC50 0.88-2.41 μM), resulting in higher selectivity indices (SI 3.65-10.05), compared to the GM (EC50 0.94-3.05 μM, SI 1.66-5.40). GM appeared to be more toxic than AM in both Vero E6 and Calu-3 cells. Cell-based anti-attachment and time-of-addition suggested that the potential molecular target could be at the post-infection. 3CLpro activity and ACE2 binding were interfered with in a dose-dependent manner but were insufficient to be a major target. Combinatorial network-based interaction and chemical similarity ensemble approach (SEA) suggested that fatty acid synthase (FASN), which was critical for SARS-CoV-2 replication, could be a target of AM and GM.

Conclusion

AM and GM inhibited SARS-CoV-2 with the highest potency at the wild-type B and the lowest at the B.1.1.529. Multiple targets were expected to integratively inhibit viral replication in cell-based system.

Hepatitis B Virus Genotypes and Subgenotypes Circulating in Infected Residents in a Country with High Vaccination Rate

Despite the availability of a vaccine against hepatitis B virus (HBV), this infection still causes public health problems, particularly in susceptible populations. In Portugal, universal free vaccination started in 1994, and most HBV infections are diagnosed in immigrants from high-prevalence countries. Our aim was to assess the pattern of HBV genotypes/subgenotypes in samples collected between 2017 and 2021 from a convenience sample of 70 infected residents in Portugal. The HBV pol/HBsAg region was amplified and sequenced, allowing the analysis of RT sequences submitted to phylogenetic analysis and mutations assessment. A total of 37.1% of samples were from native Portuguese, aged 25-53 years (mean: 36.7 years), and the remaining samples were from individuals born outside of Portugal. A high diversity of HBV was identified: subgenotypes A1-A3 in 41.0% (16/39); D1, D3, and D4 in 30.7% (12/39); E in 23.1% (9/39); and F4 in 2.6% (1/39). Besides genotypes A and D, Portuguese were also infected with genotypes E and F, which are prevalent in Africa and South America, respectively. Resistance mutations in RT sequences were not found. The findings provide valuable insights for updating the HBV molecular epidemiology in Portugal. However, successful strategies to prevent and control the infection are still needed in the country, especially among susceptible and vulnerable populations.

A Case of Rapidly Diagnosed Mycobacterium intracellulare in a Frail Geriatric Patient With Multimorbidity

The prevalence of non-tuberculous mycobacteria (NTM) infections has been on the rise in recent years, especially among the elderly population and other immunocompromised groups. Risk factors for NTM infections include advanced age, preexisting pulmonary diseases, and low body mass index. This study presents a case of NTM pulmonary disease attributed to Mycobacterium intracellulare, which was rapidly identified using metagenomic next-generation sequencing (mNGS). An 82-year-old male presented with persistent fever, cough, and shortness of breath. Initial assessments revealed an elevated white blood cell count and high-sensitivity C-reactive protein, with chest CT showing newly formed nodular shadows and cavity formation. Sputum tests confirmed NTM infection through positive acid-fast staining and mNGS, which rapidly identified M. intracellulare within 48 hours. Subsequent sputum samples confirmed the diagnosis using traditional methods. The patient had a complex medical history, including pulmonary tuberculosis, chronic pancreatitis, chronic hepatitis B, diabetes, and malnutrition. The patient was treated with a combination of cefotaxime, moxifloxacin, clarithromycin, and acetylcysteine, in addition to receiving nutritional support. After the treatment, there was an improvement in symptoms, normalization of body temperature, and a decrease in cough and sputum production. This case highlights the significance of mNGS in promptly diagnosing and treating NTM pulmonary disease, especially in elderly patients with various underlying health conditions. The collaborative effort among different medical specialties enabled more thorough patient care, ultimately leading to better outcomes. Incorporating cutting-edge diagnostic techniques such as mNGS alongside a holistic treatment approach is crucial for the successful management of NTM infections in at-risk populations.

A critical review of diagnostic and prognostic markers of chronic hepatitis B infection

A major worldwide health concern, chronic hepatitis B necessitates precise prognostic and diagnostic indicators for clinical guidance. This article highlights the clinical importance and current issues of the major markers used in both the detection and prognosis of chronic hepatitis B. An important indicator of an ongoing and persistent infection is the hepatitis B surface antigen. Hepatitis B virus DNA quantification monitoring aids in assessing viral load and hepatic cancer risk. While limited evidence of liver damage is provided by alanine aminotransferase levels, the hepatitis B core antibody verifies acute infection. Seroconversion to the hepatitis B e antibody is linked to a lower risk of disease development, and the hepatitis B e antigen status is a critical prognostic factor. Treatment choices are guided by a biopsy of the liver or minimally invasive liver fibrosis detection. Genotypes of the hepatitis B virus and host variables influence the prognosis by adding to the disease's variability. Noninvasive techniques to evaluate the severity of the disease are provided by serum markers of fibrosis, such as the fibrosis score based on four criteria and the aspartate aminotransferase-to-platelet ratio index. The requirement for indicators that distinguish between distinct viral phases and increase specificity in evaluating liver damage is one of the challenges facing chronic hepatitis B research. Even though it is quite difficult to find reliable biomarkers for resistance especially when it comes to hepatocellular cancer risk estimation, there are advanced methods, which include imaging and omics that can help in improving the accuracy of the diagnostics and prognosis. Interventions early point that improve patient outcomes are made possible using diagnostics and prognostics as they are quite effective in managing the complicated landscape of chronic hepatitis B. Key in addressing these challenges today and improving the diagnostic and prognostic markers in the future, particularly those that would support the development of successful treatment plans for people living with chronic hepatitis B virus (HBV), are scientific research, technological advances and collaborations.

Etiologically Significant microRNAs in Hepatitis B Virus-Induced Hepatocellular Carcinoma

Hepatitis B virus (HBV) infection has been causally linked to hepatocellular carcinoma (HCC) in more than 50% cases. MicroRNAs (miRNAs) play cross-cutting mechanistic roles in the complex interplay between viral pathogenesis, host survival, and clinical outcomes. The present study set out to identify etiologically significant human miRNAs associated with HBV infection in liver-related pathologies leading to HCC. In diverse tissue types, we assembled 573 miRNAs differentially expressed in HBV-associated liver pathologies, HBV infection, fibrosis, cirrhosis, acute on chronic liver failure, and HCC. Importantly, 43 human differentially expressed miRNAs (hDEmiRs) were regulated in serum/plasma and liver tissue of patients with HBV-positive conditions. However, only two hDEmiRs, hsa-miR-21-5p and hsa-miR-143-3p, were regulated across all disease conditions. To shortlist the functional miRNAs in HBV-induced HCC pathogenesis, a reverse bioinformatics analysis was performed using eight GEO datasets and the TCGA database containing the list of differentially regulated mRNAs in HCC. A comparative study using these data with the identified targets of hDEmiRs, a set of unidirectionally regulated hDEmiRs with the potential to modulate mRNAs in HCC, were found. Moreover, our study identified five miRNAs; hsa-miR-98-5p, hsa-miR-193b-3p, hsa-miR-142-5p, hsa-miR-522-5p, and hsa-miR-370-3p targeting PIGC, KNTC1, CSTF2, SLC41A2, and RAB17, respectively, in HCC. These hDEmiRs and their targets could be pivotal in HBV infection and subsequent liver pathologies modulating HCC clinical progression. HBV infection is the largest contributor to HCC, and the present study comprises the first of its kind compendium of hDEmiRs related to HBV-related pathologies.

Interim analysis of the PARADISE study: Benefits of add-on peginterferon-α in NA-treated patients with CHB

This study aimed to investigate whether peginterferon-α (IFN) add-on nucleos(t)ide analogs(NAs) can further reduce hepatocellular carcinoma(HCC) risk compared with NAs monotherapy in NA-treated patients with chronic hepatitis B(CHB). In this multi-center randomized controlled trial "PARADISE study" (NCT05671315), CHB patients with intermediate to high risk of HCC after more than 24-week NAs pretreatment were recruited, randomized to two groups at a ratio of 1:2 and followed up for 240 weeks. NAs group maintained NAs monotherapy, while IFN + NAs group received IFN add-on NAs therapy for 48 weeks, then switched to NAs monotherapy. Totally, 196 patients were included in interim analysis (NAs group 68, IFN + NAs group 128). The 96-week cumulative HCC incidence was lower in IFN + NAs group than NAs group (0% vs. 4.5%, p < 0.05). Compared with NAs group, IFN + NAs group had significantly higher rates of HBsAg loss at week 48 and 96 (22.7% vs. 0%; 16.7% vs. 0%, both p < 0.05). A new scoring system was established to predict HBsAg decline >2log10 IU/ml, HBsAg <10 IU/ml or HBsAg loss at the end of 48-week IFN treatment. The area under ROC curve was 0.914, 0.922 or 0.905 in the original cohort (n = 128) and 0.896, 0.896 or 0.864 in the external validation cohort (n = 162) for the aforementioned three outcomes, respectively. IFN add-on NAs therapy may suggest the dual benefits of reducing HCC development and facilitating HBsAg loss among NA-treated CHB patients with intermediate to high risk of HCC. The new scoring system helps to make the most of IFN treatment for a higher cost-effectiveness in healthcare.

SARS-CoV-2 journey: from alpha variant to omicron and its sub-variants

The COVID-19 pandemic has affected hundreds of millions of individuals and caused more than six million deaths. The prolonged pandemic duration and the continual inter-individual transmissibility have contributed to the emergence of a wide variety of SARS-CoV-2 variants. Genomic surveillance and phylogenetic studies have shown that substantial mutations in crucial supersites of spike glycoprotein modulate the binding affinity of the evolved SARS-COV-2 lineages to ACE2 receptors and modify the binding of spike protein with neutralizing antibodies. The immunological spike mutations have been associated with differential transmissibility, infectivity, and therapeutic efficacy of the vaccines and the immunological therapies among the new variants. This review highlights the diverse genetic mutations assimilated in various SARS-CoV-2 variants. The implications of the acquired mutations related to viral transmission, infectivity, and COVID-19 severity are discussed. This review also addresses the effectiveness of human neutralizing antibodies induced by SARS-CoV-2 infection or immunization and the therapeutic antibodies against the ascended variants.

A retrospective study to determine the correlation among HBV PreS1 antigen, HBV e antigen, alanine aminotransferase, and HBV DNA

BACKGROUND AND AIM

Hepatitis B virus (HBV) infection presents with indicators of varying clinical significance. We aimed to evaluate the correlation among HBV Pre-S1 antigen (HBV PreS1-Ag), HBV e antigen (HBeAg), HBV DNA, and alanine aminotransferase (ALT) levels.

METHODS

We retrospectively analyzed 6180 serum samples collected between 2020 and 2022 at the Shanghai General Hospital, China. Data regarding PreS1-Ag, HBeAg, ALT, and HBV DNA were compiled. Correlation analyses and cross-tabulations were employed to explore the diagnostic indicators.

RESULTS

The detection rates of both antigen indicators showed a proportional increase with HBV DNA loads. The correlation between PreS1-Ag and HBV DNA (r = 0.616) was stronger than that between HBeAg and HBV DNA (r = 0.391). The specificity of PreS1-Ag (84.30 %) was lower than that of HBeAg (97.44 %), whereas the sensitivity of HBeAg (91.13 %) significantly surpassed that of PreS1-Ag (29.56 %). Among the HBV DNA positive patients, 92.04 % tested positive for at least one indicator, which exceeded the rate of PreS1+HBeAg- and PreS1-HBeAg+ (52. 28 % and 68. 56 %, respectively). Only 1.75 % of the patients exhibited double negativity, which was lower than the percentage of patients with single negativity (1.95 % and 12.00 % for PreS1-Ag and HBeAg, respectively). The PreS1 levels correlated with ALT levels (r = 0.317); patients with PreS1-positive status had higher ALT levels than patients with PreS1-negative status.

CONCLUSION

PreS1-Ag is a more robust HBV replication indicator than HBeAg. PreS1-Ag displayed high sensitivity, whereas HBeAg demonstrated high specificity. Moreover, PreS1-Ag levels correlated with ALT levels. A combination of these indicators demonstrated dependable clinical value for detecting HBV infection and evaluating liver function.

Genetic diversity and occult hepatitis B infection in Africa: A comprehensive review

BACKGROUND

Occult hepatitis B infection (OBI) is a globally prevalent infection, with its frequency being influenced by the prevalence of hepatitis B virus (HBV) infection in a particular geographic region, including Africa. OBI can be transmitted through blood transfusions and organ transplants and has been linked to the development of hepatocellular carcinoma (HCC). The associated HBV genotype influences the infection.

AIM

To highlight the genetic diversity and prevalence of OBI in Africa.

METHODS

This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and involved a comprehensive search on PubMed, Google Scholar, Science Direct, and African Journals Online for published studies on the prevalence and genetic diversity of OBI in Africa.

RESULTS

The synthesis included 83 articles, revealing that the prevalence of OBI varied between countries and population groups, with the highest prevalence being 90.9% in patients with hepatitis C virus infection and 38% in blood donors, indicating an increased risk of HBV transmission through blood transfusions. Cases of OBI reactivation have been reported following chemotherapy. Genotype D is the predominant, followed by genotypes A and E.

CONCLUSION

This review highlights the prevalence of OBI in Africa, which varies across countries and population groups. The study also demonstrates that genotype D is the most prevalent.

The impact of HBx protein on mitochondrial dynamics and associated signaling pathways strongly depends on the hepatitis B virus genotype

Chronic hepatitis B virus (HBV) infections are strongly associated with liver cirrhosis, inflammation, and hepatocellular carcinoma. In this context, the viral HBx protein is considered as a major factor influencing HBV-associated pathogenesis through deregulation of multiple cellular signaling pathways and is therefore a potential target for prognostic and therapeutic applications. However, HBV-associated pathogenesis differs significantly between genotypes, with the relevant factors and in particular the contribution of the genetic diversity of HBx being largely unknown. To address this question, we studied the specific genotype-dependent impact of HBx on cellular signaling pathways, focusing in particular on morphological and functional parameters of mitochondria. To exclusively investigate the impact of HBx of different genotypes on integrity and function of mitochondria in the absence of additional viral factors, we overexpressed HBx in Huh7 or HepG2 cells. Key signaling pathways were profiled by kinome analysis and correlated with expression levels of mitochondrial and pathogenic markers. Conclusively, HBx of genotypes A and G caused strong disruption of mitochondrial morphology alongside an induction of PTEN-induced putative kinase 1/Parkin-mediated mitophagy. These effects were only moderately dysregulated by genotypes B and E, whereas genotypes C and D exhibit an intermediate effect in this regard. Accordingly, changes in mitochondrial membrane potential and elevated reactive oxygen species production were associated with the HBx-mediated dysfunction among different genotypes. Also, genotype-related differences in mitophagy induction were identified and indicated that HBx-mediated changes in the mitochondria morphology and function strongly depend on the genotype. This indicates a relevant role of HBx in the process of genotype-dependent liver pathogenesis of HBV infections and reveals underlying mechanisms.IMPORTANCEThe hepatitis B virus is the main cause of chronic liver disease worldwide and differs in terms of pathogenesis and clinical outcome among the different genotypes. Furthermore, the viral HBx protein is a known factor in the progression of liver injury by inducing aberrant mitochondrial structures and functions. Consequently, the selective removal of dysfunctional mitochondria is essential to maintain overall cellular homeostasis and cell survival. Consistent with the intergenotypic difference of HBV, our data reveal significant differences regarding the impact of HBx of different genotypes on mitochondrial dynamic and function and thereby on radical oxygen stress levels within the cell. We subsequently observed that the induction of mitophagy differs significantly across the heterogenetic HBx proteins. Therefore, this study provides evidence that HBx-mediated changes in the mitochondria dynamics and functionality strongly depend on the genotype of HBx. This highlights an important contribution of HBx in the process of genotype-dependent liver pathogenesis.

In Silico and In Vitro Evaluation of the Molecular Mimicry of the SARS-CoV-2 Spike Protein by Common Short Constituent Sequences (cSCSs) in the Human Proteome: Toward Safer Epitope Design for Vaccine Development

Spike protein sequences in SARS-CoV-2 have been employed for vaccine epitopes, but many short constituent sequences (SCSs) in the spike protein are present in the human proteome, suggesting that some anti-spike antibodies induced by infection or vaccination may be autoantibodies against human proteins. To evaluate this possibility of "molecular mimicry" in silico and in vitro, we exhaustively identified common SCSs (cSCSs) found both in spike and human proteins bioinformatically. The commonality of SCSs between the two systems seemed to be coincidental, and only some cSCSs were likely to be relevant to potential self-epitopes based on three-dimensional information. Among three antibodies raised against cSCS-containing spike peptides, only the antibody against EPLDVL showed high affinity for the spike protein and reacted with an EPLDVL-containing peptide from the human unc-80 homolog protein. Western blot analysis revealed that this antibody also reacted with several human proteins expressed mainly in the small intestine, ovary, and stomach. Taken together, these results showed that most cSCSs are likely incapable of inducing autoantibodies but that at least EPLDVL functions as a self-epitope, suggesting a serious possibility of infection-induced or vaccine-induced autoantibodies in humans. High-risk cSCSs, including EPLDVL, should be excluded from vaccine epitopes to prevent potential autoimmune disorders.

Development of an automated amplicon-based next-generation sequencing pipeline for rapid detection of bacteria and fungi directly from clinical specimens

The timely identification of microbial pathogens is essential to guide targeted antimicrobial therapy and ultimately, successful treatment of an infection. However, the yield of standard microbiology testing (SMT) is directly related to the duration of antecedent antimicrobial therapy as SMT culture methods are dependent on the recovery of viable organisms, the fastidious nature of certain pathogens, and other pre-analytic factors. In the last decade, metagenomic next-generation sequencing (mNGS) has been successfully utilized as a diagnostic tool for various applications within the clinical laboratory. However, mNGS is resource, time, and labor-intensive-requiring extensive laborious preliminary benchwork, followed by complex bioinformatic analysis. We aimed to address these shortcomings by developing a largely Automated targeted Metagenomic next-generation sequencing (tmNGS) PipeLine for rapId inFectIous disEase Diagnosis (AMPLIFIED) to detect bacteria and fungi directly from clinical specimens. Therefore, AMPLIFIED may serve as an adjunctive approach to complement SMT. This tmNGS pipeline requires less than 1 hour of hands-on time before sequencing and less than 2 hours of total processing time, including bioinformatic analysis. We performed tmNGS on 50 clinical specimens with concomitant cultures to assess feasibility and performance in the hospital laboratory. Of the 50 specimens, 34 (68%) were from true clinical infections. Specimens from cases of true infection were more often tmNGS positive compared to those from the non-infected group (82.4% vs 43.8%, respectively, P = 0.0087). Overall, the clinical sensitivity of AMPLIFIED was 54.6% with 85.7% specificity, equating to 70.6% and 75% negative and positive predictive values, respectively. AMPLIFIED represents a rapid supplementary approach to SMT; the typical time from specimen receipt to identification of potential pathogens by AMPLIFIED is roughly 24 hours which is markedly faster than the days, weeks, and months required to recover bacterial, fungal, and mycobacterial pathogens by culture, respectively.

IMPORTANCE

To our knowledge, this represents the first application of an automated sequencing and bioinformatics pipeline in an exclusively pediatric population. Next-generation sequencing is time-consuming, labor-intensive, and requires experienced personnel; perhaps contributing to hesitancy among clinical laboratories to adopt such a test. Here, we report a strong case for use by removing these barriers through near-total automation of our sequencing pipeline.

Programmed Death 1 and Cytotoxic T-Lymphocyte-Associated Protein 4 Gene Expression in Peripheral Blood Mononuclear Cells Can Serve as Prognostic Biomarkers for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a highly aggressive form of liver cancer with poor prognosis. The lack of reliable biomarkers for early detection and accurate diagnosis and prognosis poses a significant challenge to its effective clinical management. In this study, we investigated the diagnostic and prognostic potential of programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) expression in peripheral blood mononuclear cells (PBMCs) in HCC. PD-1 and CTLA-4 gene expression was analyzed comparatively using PBMCs collected from HCC patients and healthy individuals. The results revealed higher PD-1 gene expression levels in patients with multifocal tumors, lymphatic invasion, or distant metastasis than those in their control counterparts. However, conventional serum biomarkers of liver function do not exhibit similar correlations. In conclusion, PD-1 gene expression is associated with OS and PFS and CTLA-4 gene expression is associated with OS, whereas the serum biomarkers analyzed in this study show no significant correlation with survival in HCC. Hence, PD-1 and CTLA-4 expressed in PBMCs are considered potential prognostic biomarkers for patients with HCC that can facilitate prediction of malignancy, response to currently available HCC treatments, and overall survival.

Origin and dispersal history of Hepatitis B virus in Eastern Eurasia

Hepatitis B virus is a globally distributed pathogen and the history of HBV infection in humans predates 10000 years. However, long-term evolutionary history of HBV in Eastern Eurasia remains elusive. We present 34 ancient HBV genomes dating between approximately 5000 to 400 years ago sourced from 17 sites across Eastern Eurasia. Ten sequences have full coverage, and only two sequences have less than 50% coverage. Our results suggest a potential origin of genotypes B and D in Eastern Asia. We observed a higher level of HBV diversity within Eastern Eurasia compared to Western Eurasia between 5000 and 3000 years ago, characterized by the presence of five different genotypes (A, B, C, D, WENBA), underscoring the significance of human migrations and interactions in the spread of HBV. Our results suggest the possibility of a transition from non-recombinant subgenotypes (B1, B5) to recombinant subgenotypes (B2 - B4). This suggests a shift in epidemiological dynamics within Eastern Eurasia over time. Here, our study elucidates the regional origins of prevalent genotypes and shifts in viral subgenotypes over centuries.

Comprehensive analysis of antigenic variations and genomic properties of hepatitis B virus in clinical samples in the mid-north east region of Bangladesh

This investigation delineates an exhaustive analysis of the clinical, immunological, and genomic landscapes of hepatitis B virus (HBV) infection across a cohort of 22 verified patients. The demographic analysis unveiled a pronounced male bias (77.27%), with patient ages spanning 20 to 85 years and durations of illness ranging from 10 days to 4 years. Predominant clinical manifestations included fever, fatigue, anorexia, abdominal discomfort, and arthralgia, alongside observed co-morbidities such as chronic renal disorders and hepatocellular carcinoma. Antigenic profiling of the HBV envelope proteins elucidated significant heterogeneity among the infected subjects, particularly highlighted by discordances in the detection capabilities of small and large HBsAg assays, suggesting antigenic diversity. Quantitative assessment of viral loads unveiled a broad spectrum, accompanied by atypical HBeAg reactivity patterns, challenging the reliability of existing serological markers. Correlative studies between viral burden and antigenicity of the envelope proteins unearthed phenomena indicative of diagnostic evasion. Notably, samples demonstrating robust viral replication were paradoxically undetectable by the large HBsAg ELISA kit, advocating for more sophisticated diagnostic methodologies. Genotypic examination of three HBV isolates classified them as genotype D (D2), with phylogenetic alignment to strains from various global origins. Mutational profiling identified pivotal mutations within the basic core promoter and preS2/S1 regions, associated with an augmented risk of hepatocellular carcinoma. Further, mutations discerned in the small HBsAg and RT/overlap regions were recognized as contributors to vaccine and/or diagnostic escape mechanisms. In summation, this scholarly discourse elucidates the intricate interplay of clinical presentations, antigenic diversity, and genomic attributes in HBV infection, accentuating the imperative for ongoing investigative endeavors to refine diagnostic and therapeutic modalities.

Current Progress, Challenges and Prospects in the Development of COVID-19 Vaccines

The COVID-19 pandemic has resulted in over 772 million confirmed cases, including nearly 7 million deaths, according to the World Health Organization (WHO). Leveraging rapid development, accelerated vaccine approval processes, and large-scale production of various COVID-19 vaccines using different technical platforms, the WHO declared an end to the global health emergency of COVID-19 on May 5, 2023. Current COVID-19 vaccines encompass inactivated, live attenuated, viral vector, protein subunit, nucleic acid (DNA and RNA), and virus-like particle (VLP) vaccines. However, the efficacy of these vaccines is diminishing due to the constant mutation of SARS-CoV-2 and the heightened immune evasion abilities of emerging variants. This review examines the impact of the COVID-19 pandemic, the biological characteristics of the virus, and its diverse variants. Moreover, the review underscores the effectiveness, advantages, and disadvantages of authorized COVID-19 vaccines. Additionally, it analyzes the challenges, strategies, and future prospects of developing a safe, broad-spectrum vaccine that confers sufficient and sustainable immune protection against new variants of SARS-CoV-2. These discussions not only offer insight for the development of next-generation COVID-19 vaccines but also summarize experiences for combating future emerging viruses.

Prediction model for hepatitis B e antigen seroconversion in chronic hepatitis B with peginterferon-alfa treated based on a response-guided therapy strategy

BACKGROUND

Models for predicting hepatitis B e antigen (HBeAg) seroconversion in patients with HBeAg-positive chronic hepatitis B (CHB) after nucleos(t)ide analog treatment are rare.

AIM

To establish a simple scoring model based on a response-guided therapy (RGT) strategy for predicting HBeAg seroconversion and hepatitis B surface antigen (HBsAg) clearance.

METHODS

In this study, 75 previously treated patients with HBeAg-positive CHB underwent a 52-week peginterferon-alfa (PEG-IFNα) treatment and a 24-wk follow-up. Logistic regression analysis was used to assess parameters at baseline, week 12, and week 24 to predict HBeAg seroconversion at 24 wk post-treatment. The two best predictors at each time point were used to establish a prediction model for PEG-IFNα therapy efficacy. Parameters at each time point that met the corresponding optimal cutoff thresholds were scored as 1 or 0.

RESULTS

The two most meaningful predictors were HBsAg ≤ 1000 IU/mL and HBeAg ≤ 3 S/CO at baseline, HBsAg ≤ 600 IU/mL and HBeAg ≤ 3 S/CO at week 12, and HBsAg ≤ 300 IU/mL and HBeAg ≤ 2 S/CO at week 24. With a total score of 0 vs 2 at baseline, week 12, and week 24, the response rates were 23.8%, 15.2%, and 11.1% vs 81.8%, 80.0%, and 82.4%, respectively, and the HBsAg clearance rates were 2.4%, 3.0%, and 0.0%, vs 54.5%, 40.0%, and 41.2%, respectively.

CONCLUSION

We successfully established a predictive model and diagnosis-treatment process using the RGT strategy to predict HBeAg and HBsAg seroconversion in patients with HBeAg-positive CHB undergoing PEG-IFNα therapy.

Overview of the immunological mechanisms in hepatitis B virus reactivation: Implications for disease progression and management strategies

Hepatitis B virus (HBV) reactivation is a clinically significant challenge in disease management. This review explores the immunological mechanisms underlying HBV reactivation, emphasizing disease progression and management. It delves into host immune responses and reactivation's delicate balance, spanning innate and adaptive immunity. Viral factors' disruption of this balance, as are interactions between viral antigens, immune cells, cytokine networks, and immune checkpoint pathways, are examined. Notably, the roles of T cells, natural killer cells, and antigen-presenting cells are discussed, highlighting their influence on disease progression. HBV reactivation's impact on disease severity, hepatic flares, liver fibrosis progression, and hepatocellular carcinoma is detailed. Management strategies, including anti-viral and immunomodulatory approaches, are critically analyzed. The role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent reactivation. In conclusion, this comprehensive review furnishes a holistic view of the immunological mechanisms that propel HBV reactivation. With a dedicated focus on understanding its implications for disease progression and the prospects of efficient management strategies, this article contributes significantly to the knowledge base. The more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches, ultimately enhancing disease management and elevating patient outcomes. The dynamic landscape of management strategies is critically scrutinized, spanning anti-viral and immunomodulatory approaches. The role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation.

Hepatitis B virus genotype surveillance in Canadian blood donors and a referred patient population, 2016-2021

BACKGROUND AND OBJECTIVES

Hepatitis B virus (HBV) genotypes (A-H) have a distinct geographic distribution and are highly associated with the country of birth. Canada has experienced increased immigration over the past decade, primarily from regions where HBV is endemic. This study investigated the proportions and trends of HBV genotypes within blood donor and clinical populations of Canada over the period 2016-2021.

MATERIALS AND METHODS

Study samples involved two cohorts: (1) Canadian blood donors (n = 246) deferred from donation due to HBV test positivity and (2) chronic HBV patients from across Canada (clinically referred population, n = 3539). Plasma or serum was extracted, and the surface antigen and/or polymerase-coding region was amplified and sequenced to determine genotype by phylogenetic analysis.

RESULTS

Six (A-E, G) and eight (A-H) HBV genotypes were detected among deferred blood donors and the clinically referred population, respectively. Differences in HBV genotype proportions between the two cohorts were observed across Canada. Males comprised most of the referred population among genotypes A-E (p < 0.0001), except for genotypes B and C. The median age was younger among blood donors (36 years [range 17-72]) compared with the referred population (41 years [range 0-99]). Distinct trends of increasing (E, referred; B, blood donor) and decreasing genotype prevalence were observed over the study period.

CONCLUSION

HBV genotypes in Canada are highly diverse, suggesting a large immigrant population. Observed trends in genotype prevalence and proportional differences among cohorts imply shifts among the HBV-infected population of Canada, which warrants continued surveillance.

Hepatitis B virus genotypes associated with pregnant women in Northern Thailand

BACKGROUND

Mother-to-child transmission of hepatitis B virus (HBV) is the major route of transmission causing persistent infection. The prevalence of HBV infection and HBV genotypes found in different geographical areas varies from country to country. Therefore, this study was conducted to identify the HBV genotypes in HBV-infected pregnant women in Northern Thailand.

METHODS

Stored blood samples that were collected from 145 HBsAg-positive pregnant women who gave birth at Maharaj Nakorn Chiang Mai Hospital, Chiang Mai, Thailand from 2017 to 2020 were analyzed. The partial nucleotide sequence of the S gene of HBV was amplified by nested PCR and sequenced. All sequences were analyzed phylogenetically together with the reference strains to define the HBV genotypes.

RESULTS

A total of 31 blood samples from 145 HBsAg-positive pregnant women were positive for HBV by nested PCR. The detected HBV strains were identified as presumptive subgenotypes C1 (77.4%; 24/31), B9 (9.7%; 3/31), C2 (3.2%; 1/31), B2 (3.2%; 1/31), B4 (3.2%; 1/31), and presumptive B4/C2 recombinant subgenotype (3.2%; 1/31).

CONCLUSIONS

The findings revealed that presumptive subgenotype C1 was the most common subgenotype circulating in pregnant women in Northern Thailand and accounted for 77.4% of cases, followed by presumptive subgenotypes B9, C2, B2, and B4. Furthermore, this study reported, for the first time in Thailand, the HBV genotypes and presumptive subgenotypes, particularly subgenotype B9 circulating in pregnant women.

Multiple structural flavors of RNase P in precursor tRNA processing

The precursor transfer RNAs (pre-tRNAs) require extensive processing to generate mature tRNAs possessing proper fold, structural stability, and functionality required to sustain cellular viability. The road to tRNA maturation follows an ordered process: 5'-processing, 3'-processing, modifications at specific sites, if any, and 3'-CCA addition before aminoacylation and recruitment to the cellular protein synthesis machinery. Ribonuclease P (RNase P) is a universally conserved endonuclease in all domains of life, performing the hydrolysis of pre-tRNA sequences at the 5' end by the removal of phosphodiester linkages between nucleotides at position -1 and +1. Except for an archaeal species: Nanoarchaeum equitans where tRNAs are transcribed from leaderless-position +1, RNase P is indispensable for life and displays fundamental variations in terms of enzyme subunit composition, mechanism of substrate recognition and active site architecture, utilizing in all cases a two metal ion-mediated conserved catalytic reaction. While the canonical RNA-based ribonucleoprotein RNase P has been well-known to occur in bacteria, archaea, and eukaryotes, the occurrence of RNA-free protein-only RNase P in eukaryotes and RNA-free homologs of Aquifex RNase P in prokaryotes has been discovered more recently. This review aims to provide a comprehensive overview of structural diversity displayed by various RNA-based and RNA-free RNase P holoenzymes towards harnessing critical RNA-protein and protein-protein interactions in achieving conserved pre-tRNA processing functionality. Furthermore, alternate roles and functional interchangeability of RNase P are discussed in the context of its employability in several clinical and biotechnological applications. This article is categorized under: RNA Processing > tRNA Processing RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes.

Expression and purification of Hepatitis B virus core antigen using Escherichia coli and its utilization for the diagnosis of Hepatitis B virus infections

Hepatitis B virus (HBV) is responsible for most of the viral hepatitis worldwide. HBV is a partially double stranded DNA virus that is composed of four main open reading frames (ORFs) encoding its important antigens, namely hepatitis B surface antigen (HBsAg), hepatitis B core antigen (HBcAg), HBV polymerase and hepatitis B X antigen (HBxAg). In this study, we report a successful method for the cloning and expression of HBcAg. The ORF of HBcAg was successfully amplified using polymerase chain reaction (PCR), cloned into the expression vector pRSET-B and transformed to Escherichia coli (E. coli) BL-21 (DE3) pLysS strain for protein expression. Successful expression of HBcAg was accomplished, in which an induced protein with a molecular weight of 24 kDa was obtained and confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. The produced HBcAg was successfully used for the diagnosis of HBV infected patient through detection of antibodies against HBcAg (anti-HBcAg) in the serum of the patient utilizing Western blotting. Overall, this study provides a simple, convenient and efficient protocol for the production of HBcAg that can be used as an important candidate to study the diagnosis and prognosis of HBV disease, as well as for understanding the epidemiological prevalence of HBV cases and production of anti-HBcAg.

Quality and composition of archived nucleic acids after use in SARS-CoV-2 molecular testing

BACKGROUND

Reverse transcription real-time PCR (rRT-PCR) has been a gold-standard method to detect SARS-CoV-2, for which quality assessment of nucleic acids (NAs) is not needed. In order to prepare for future use, we evaluated NA quality from archived SARS-CoV-2 rRT-PCR samples.

METHODS

NA samples were collected in February 2021 and extracted using the QIAamp DSP Virus Spin Kit, (53 SARS-CoV-2-positive and 100 SARS-CoV-2-negative). Quality, quantity, and purity of NA were measured spectrophotometrically or fluorescently. Droplet digital PCR was used to characterize the double strand DNA (dsDNA) origin and composition by quantifying 16S rDNA and RPP30.

RESULTS

The RIN and purity were not significantly different between groups (p = 0.3828). RNA quantity was significantly higher than dsDNA in both groups (p < 0.0001); both dsDNA and RNA quantity were significantly higher in positive samples (dsDNA, RNA p = 0.021). For dsDNA, 16S rDNA copies were significantly greater than RPP30 in both groups (p < 0.0001), and RPP30 were significantly higher in positive samples (p < 0.0001).

CONCLUSIONS

Archived NA quality after SARS-CoV-2 rRT-PCR was guaranteed for subsequent molecular research using human or bacterial DNA, especially for short targets.

Current Progress of Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV) Vaccine Development

SFTSV is an emerging tick-borne virus causing hemorrhagic fever with a case fatality rate (CFR) that can reach up to 27%. With endemic infection in East Asia and the recent spread of the vector tick to more than 20 states in the United States, the SFTSV outbreak is a globally growing public health concern. However, there is currently no targeted antiviral therapy or licensed vaccine against SFTSV. Considering the age-dependent SFTS pathogenesis and disease outcome, a sophisticated vaccine development approach is required to safeguard the elderly population from lethal SFTSV infection. Given the recent emergence of SFTSV, the establishment of animal models to study immunogenicity and protection from SFTS symptoms has only occurred recently. The latest research efforts have applied diverse vaccine development approaches-including live-attenuated vaccine, DNA vaccine, whole inactivated virus vaccine, viral vector vaccine, protein subunit vaccine, and mRNA vaccine-in the quest to develop a safe and effective vaccine against SFTSV. This review aims to outline the current progress in SFTSV vaccine development and suggest future directions to enhance the safety and efficacy of these vaccines, ensuring their suitability for clinical application.

Prevalence and influential factors of isolated hepatitis B core antibody positivity in a Chinese adult population

Isolated anti-HBc (IAHBc) is defined by the presence of anti-HBc in the absence of HBsAg and hepatitis B surface antibody (anti-HBs). IAHBc is of great clinical significance as a specific pattern of HBV infection, but IAHBc has not been fully clarified. This study aimed to explore the prevalence and influential factors of IAHBc from routine examination results of inpatients.A total of 61,247 individuals were included in the study, with a median age of 55 years (range: 43-68), and a male-to-female ratio of 0.90:1. The prevalence of current HBV infection (HBsAg positive) was 6.82%, while the prevalence of previous HBV infection (HBsAg negative but anti-HBc positive) was 48.63%. The prevalence of IAHBc was 12.31%. Among them, the rates for males were 7.10%, 52.16%, and 13.70%, respectively, which were significantly higher than the rates for females at 6.56%, 45.45%, and 11.06% (P < 0.05). The prevalence rates mentioned above were significantly reduced after vaccination (P < 0.05). The prevalence of IAHBc increases with age, rising from 0.23% in the age group of 15-29 years to 13.57% in individuals aged 80 and above. After the age of 50, the prevalence of IAHBc closely parallels the previous infection rate but shows no significant association with the current infection rate (P > 0.05). Among IAHBc individuals, approximately 33.83% tested positive for anti-HBe, and their anti-HBc absorbance values were significantly higher compared to anti-HBe negative individuals (7.08 and 5.31, P < 0.01). The prevalence of anti-HBe positivity among IAHBc individuals does not vary with changes in the previous infection rate and age (P > 0.05).

Prediction Model for the Clearance of Hepatitis B Surface Antigen in Patients with Chronic Hepatitis B before Interferon Therapy: A Prospective Case-Control Study

To evaluate the prediction model comprised of patients' laboratory results and single-nucleotide polymorphism (SNP) markers of host gene for the clearance of hepatitis B surface antigen (HBsAg) in patients with chronic hepatitis B (CHB) who underwent interferon (IFN)-α therapy, this prospective case-control study enrolled 131 patients with CHB who underwent IFN-α-based regimens in our hospital between January 2015 and September 2019. Among them, 56 cases were without HBsAg clearance, while the other 75 cases had HBsAg clearance. Multivariable logistic regression analysis showed that CYP27B1 rs4646536 (odd ratio [OR] = 0.155, 95% CI: 0.030-0.807, p = 0.027), PAK4 rs9676717 (OR = 11.237, 95% CI: 1.768-71.409, p = 0.010), IL28B rs12979860 (OR = 0.059, 95% CI: 0.006-0.604, p = 0.017), baseline HBsAg (OR = 0.170, 95% CI: 0.040-0.716, p = 0.016), and HBeAg status (OR = 3.971, 95% CI: 1.138-13.859, p = 0.031) were independently associated with HBsAg clearance. The model that included rs3077, rs4646536, rs9676717, rs2850015, rs12979860, baseline HBsAg, HBeAg status, and HBV DNA had the best prediction performance for HBsAg clearance prediction, with AUC = 0.877, 80% sensitivity, and 81% specificity. In conclusion, laboratory results and gene polymorphisms before treatment might have a good predictive value for HbsAg clearance after IFN-α treatment in CHB.

Role of HBsAg levels in guiding hepatitis B virus prophylaxis in pregnancy: Insights from a multi-ethnic cohort

Pregnant mothers with chronic hepatitis B infection (CHB) need peri-partum antiviral prophylaxis (PAP) to reduce the risk of mother-to-child-transmission. Currently, PAP is recommended in those with high viral load (VL) that is, HBV DNA >200,000 IU/mL. Quantitative hepatitis B surface antigen (qHBsAg) >10,000 IU/mL, a cut-off derived primarily from hepatitis B e-antigen (HBeAg) positive antenatal cohorts in Chinese populations, is advocated as a surrogate marker of VL for guiding PAP. We investigated the utility of qHBsAg to predict high-VL in a multi-ethnic urban cohort with CHB. A consecutive cohort of women with CHB was identified from Barts Health NHS Trust databases in the United Kingdom. We included women with paired HBV DNA and qHBsAg during pregnancy. Women already on antiviral at conception were excluded. A total of 769 pregnancies in 678 CHB pregnant mothers (median age 31 years-old, 8.6% HBeAg+) were included. At median gestational age of 15.3 weeks, HBV DNA was 336 (IQR 44-2998) IU/mL, with 65 (8.5%) being high-VL. Serum qHBsAg was most useful in Black/Black-British/Caribbean/African (AUROC 0.946) with 100% sensitivity and 80.6% specificity to predict high-VL; but it performed less well for other ethnicities: Asian (AUROC 0.877), White (AUROC 0.797) and mixed ethnicities (AUROC 0.742). In conclusion, for settings where healthcare resources are not limited, HBV DNA remains the optimal marker to identify highly viraemic pregnancies for guiding PAP. For resource-limited settings where the prevailing cost is treatment, serum qHBsAg can be used in Black/Black British/Caribbean/African sub-cohorts, but not for other ethnicities.

[Delta hepatitis in Africa: epidemiological and clinical particularities]

In 2022, the World Health Organization (WHO) estimated that hepatitis B virus (HBV) infections caused 1.5 million deaths, mostly attributable to complications from chronic infections, cirrhosis and hepatocellular carcinoma (HCC). Despite the availability of a vaccine, 296 million people were chronically infected in 2019. Asia and Africa are the continents most affected by this infection, with around 100 million people infected in Africa as a whole.Hepatitis Delta or D virus (HDV), which is a "satellite" virus of HBV, is often misunderstood and its diagnosis remains neglected. However, it is associated with acute fulminant forms and chronic forms of hepatitis leading to a more rapid evolution towards cirrhosis and HCC than during HBV mono-infection. Research on these two viruses HBV and HDV has progressed a lot in recent years, and new treatments are currently in development.In people living with the human immunodeficiency virus (PlHIV), liver disease is a major cause of morbidity and mortality. Due to common modes of transmission, dual or triple HIV/HBV or HIV/HBV/HDV infections are relatively common, particularly in HBV endemic regions such as Africa. However, while today most co-infected patients benefit from effective treatment against both HIV and HBV, the latter is not active against HDV. In Africa, hepatitis B and D have already been the subject of several studies. However, the frequency and clinical consequences of these co-infections have been little studied in the general population and in PlHIV.This review seeks to update the epidemiological and clinical data and the therapeutic perspectives of HDV co-infections or triple infections (HIV-HBV-HDV) in Africa.

Performance evaluation of the cobas SARS-CoV-2 Duo, a novel qualitative and quantitative assay, for the detection of SARS-CoV-2 RNA

IMPORTANCE

Quantitative SARS-CoV-2 tests for viral load are necessary to guide patient treatment, as well as to determine infection control measures and policies. Although the real-time RT-PCR assays can report the Ct value to estimate the viral load, there are several serious concerns regarding the use of Ct values. Importantly, Ct values can vary significantly among between- and within-run methods. The diagnostic performance of the cobas SARS-CoV-2 Duo is appropriate. It is a precise, accurate, and sensitive method for the detection of SARS-CoV-2 RNA and is comparable to two qualitative assays (the cobas SARS-CoV-2 and the Liat cobas SARS-CoV-2 and Inf A/B). In contrast, using the Ct value to estimate viral load is not reliable, and utilization of a quantitative detection test, such as the cobas SARS-CoV-2 Duo, to accurately measure the viral load is needed.

Development of primer-probe sets to rapidly distinguish single nucleotide polymorphisms in SARS-CoV-2 lineages

Ongoing SARS-CoV-2 infections are driven by the emergence of various variants, with differential propensities to escape immune containment. Single nucleotide polymorphisms (SNPs) in the RNA genome result in altered protein structures and when these changes occur in the S-gene, encoding the spike protein, the ability of the virus to penetrate host cells to initiate an infection can be significantly altered. As a result, vaccine efficacy and prior immunity may be diminished, potentially leading to new waves of infection. Early detection of SARS-CoV-2 variants using a rapid and scalable approach will be paramount for continued monitoring of new infections. In this study, we developed minor groove-binding (MGB) probe-based qPCR assays targeted to specific SNPs in the S-gene, which are present in variants of concern (VOC), namely the E484K, N501Y, G446S and D405N mutations. A total of 95 archived SARS-CoV-2 positive clinical specimens collected in Johannesburg, South Africa between February 2021 and March 2022 were assessed using these qPCR assays. To independently confirm SNP detection, Sanger sequencing of the relevant region in the S-gene were performed. Where a PCR product could be generated and sequenced, qPCR assays were 100% concordant highlighting the robustness of the approach. These assays, and the approach described, offer the opportunity for easy detection and scaling of targeted detection of variant-defining SNPs in the clinical setting.

Sampling from upper and/or lower respiratory tract when diagnosing coronavirus disease 2019 (COVID-19) - results from a Danish cohort study

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can replicate in the upper and lower respiratory tract. We aimed to evaluate whether symptom characteristics and symptom duration prior to sampling are associated with test positivity in upper or lower respiratory tract samples.

METHODS

We conducted a retrospective cohort study in the Central Denmark Region from 14 April 2020 to 2 November 2020 including hospitalised patients with SARS-CoV-2 reverse transcriptase-polymerase chain reaction samples from both the upper and lower respiratory tract within 48 h and at least one positive test result.

RESULTS

Of 122 patients, 101 were positive in both samples (83%), 7 (5%) were positive only in the upper respiratory tract sample, and 14 (11%) were only positive in the lower respiratory tract sample. The median number of symptoms was 4 (IQR 3, 5.75) and 5 (IQR 3, 7), respectively, in patients with only a positive upper respiratory tract sample and in concordant positive patients; while 1 (IQR 1, 3) in patients with only a positive upper respiratory tract sample. 98% (120/122) of patients would have been diagnosed with coronavirus disease 2019 if supplemental sampling from the lower respiratory tract was guided by lower respiratory tract symptoms. No substantial difference in the duration of symptoms was observed across the three patient groups.

CONCLUSIONS

The presence of lower respiratory tract symptoms could have been used to determine whether supplemental sampling from the lower respiratory tract was necessary. Symptom duration was not associated with test positivity in the upper or lower respiratory tract.

A globally integrated structure of taxonomy to support biodiversity science and conservation

All aspects of biodiversity research, from taxonomy to conservation, rely on data associated with species names. Effective integration of names across multiple fields is paramount and depends on the coordination and organization of taxonomic data. We assess current efforts and find that even key applications for well-studied taxa still lack commonality in taxonomic information required for integration. We identify essential taxonomic elements from our interoperability assessment to support improved access and integration of taxonomic data. A stronger focus on these elements has the potential to involve taxonomic communities in biodiversity science and overcome broken linkages currently limiting research capacity. We encourage a community effort to democratize taxonomic expertise and language in order to facilitate maximum interoperability and integration.

Replication and Expression of the Consensus Genome of Hepatitis B Virus Genotype C from the Chinese Population

Hepatitis B virus (HBV) genotype C is a prevalent HBV genotype in the Chinese population. Although genotype C shows higher sequence heterogeneity and more severe liver disease than other genotypes, its pathogenesis and immunological traits are not yet fully elucidated. In this study, we first established and chemically synthesized the consensus sequence based on representative 138 full-length HBV genotype C genomes from the Chinese population. The pHBV1.3C plasmid system, containing a 1.3-fold full-length HBV genotype C consensus sequence, was constructed for subsequent validation. Next, we performed functional assays to investigate the replicative competence of pHBV1.3C in vitro through the transient transfection of HepG2 and Huh7 cells and validated the in vivo function via a hydrodynamic injection to BALB/c recipient mice. The in vitro investigation revealed that the extracellular HBV DNA and intracellular replicative intermediate (i.e., pregenomic RNA, pgRNA) were apparently measurable at 48 h, and the HBsAg and HBcAg were still positive in hepatoma cells at 96 h. We also found that HBsAg and HBeAg accumulated at the extracellular and intracellular levels in a time-dependent manner. The in vivo validation demonstrated that pHBV1.3C plasmids induced HBV viremia, triggered morphological changes and HBsAg- or HBcAg- positivity of hepatocytes, and ultimately caused inflammatory infiltration and focal or piecemeal necrosis in the livers of the murine recipients. HBV protein (HBsAg) colocalized with CD8+ T cells or CD4+ T cells in the liver. F4/80+ Kupffer cells were abundantly recruited around the altered murine hepatocytes. Taken together, our results indicate that the synthetic consensus sequence of HBV genotype C is replication-competent in vitro and in vivo. This genotype C consensus genome supports the full HBV life cycle, which is conducive to studying its pathogenesis and immune response, screening novel antiviral agents, and further optimizing testing and therapeutics.

Exploring the key genomic variation in monkeypox virus during the 2022 outbreak

BACKGROUND

In 2022, a global outbreak of monkeypox occurred with a significant shift in its epidemiological characteristics. The monkeypox virus (MPXV) belongs to the B.1 lineage, and its genomic variations that were linked to the outbreak were investigated in this study. Previous studies have suggested that viral genomic variation plays a crucial role in the pathogenicity and transmissibility of viruses. Therefore, understanding the genomic variation of MPXV is crucial for controlling future outbreaks.

METHODS

This study employed bioinformatics and phylogenetic approaches to evaluate the key genomic variation in the B.1 lineage of MPXV. A total of 979 MPXV strains were screened, and 212 representative strains were analyzed to identify specific substitutions in the viral genome. Reference sequences were constructed for each of the 10 lineages based on the most common nucleotide at each site. A total of 49 substitutions were identified, with 23 non-synonymous substitutions. Class I variants, which had significant effects on protein conformation likely to affect viral characteristics, were classified among the non-synonymous substitutions.

RESULTS

The phylogenetic analysis revealed 10 relatively monophyletic branches. The study identified 49 substitutions specific to the B.1 lineage, with 23 non-synonymous substitutions that were classified into Class I, II, and III variants. The Class I variants were likely responsible for the observed changes in the characteristics of circulating MPXV in 2022. These key mutations, particularly Class I variants, played a crucial role in the pathogenicity and transmissibility of MPXV.

CONCLUSION

This study provides an understanding of the genomic variation of MPXV in the B.1 lineage linked to the recent outbreak of monkeypox. The identification of key mutations, particularly Class I variants, sheds light on the molecular mechanisms underlying the observed changes in the characteristics of circulating MPXV. Further studies can focus on functional domains affected by these mutations, enabling the development of effective control strategies against future monkeypox outbreaks.

Insights into the mechanism of SARS-CoV-2 main protease autocatalytic maturation from model precursors

A critical step for SARS-CoV-2 assembly and maturation involves the autoactivation of the main protease (MProWT) from precursor polyproteins. Upon expression, a model precursor of MProWT mediates its own release at its termini rapidly to yield a mature dimer. A construct with an E290A mutation within MPro exhibits time dependent autoprocessing of the accumulated precursor at the N-terminal nsp4/nsp5 site followed by the C-terminal nsp5/nsp6 cleavage. In contrast, a precursor containing E290A and R298A mutations (MProM) displays cleavage only at the nsp4/nsp5 site to yield an intermediate monomeric product, which is cleaved at the nsp5/nsp6 site only by MProWT. MProM and the catalytic domain (MPro1-199) fused to the truncated nsp4 region also show time-dependent conversion in vitro to produce MProM and MPro1-199, respectively. The reactions follow first-order kinetics indicating that the nsp4/nsp5 cleavage occurs via an intramolecular mechanism. These results support a mechanism involving an N-terminal intramolecular cleavage leading to an increase in the dimer population and followed by an intermolecular cleavage at the C-terminus. Thus, targeting the predominantly monomeric MPro precursor for inhibition may lead to the identification of potent drugs for treatment.

Correlation Between Vitamin D Status and HBsAg Antibody Levels in Indonesian Adolescents Immunised Against Hepatitis B

Introduction

Hepatitis B virus (HBV) infection is a global health problem. Anti-hepatitis B surface antigen (HBsAg) levels increase along with vitamin D levels in adults. However, few studies have examined this relationship in adolescents. Few studies have examined the relationship between vitamin D and HBsAg antibody levels, especially in Indonesia.

Methods

This cross-sectional study examined vitamin D and anti-HBsAg levels before and after hepatitis B immunisation. All subjects blood was taken to check for vitamin D level. This study was part of the Safety and Preliminary of Immunogenicity Following Recombinant Hepatitis B (Bio Farma) Vaccine in Adults and Children Phase I trial.

Results

This study found that 25-hydroxyvitamin D [25(OH)D] status was primarily deficient based on endocrine criteria. The children's hepatitis B antibody response was mostly <10 mIU/mL before and ≥10 mIU/mL after vaccination. There was a relationship between sex and 25(OH)D status, with median 25(OH)D levels higher in females (18.2 ng/mL) than in males (9.8 ng/mL). However, the relationship between vitamin 25(OH)D status and anti-HBsAg levels pre- and post-vaccination was not significant.

Discussion

However, some research found that vitamin D supplementation after immunisation did not impact vaccine response, several studies have reported that vitamin D can decrease HBV replication through various mechanisms, including reducing viral transcription and interfering with viral protein synthesis.

Conclusion

There was no relationship between 25(OH)D status and anti-HBsAg levels. Further research is needed to elucidate the underlying mechanisms and establish optimal treatment strategies.