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On 27 May 2024, the Cuban Ministry of Health reported the first outbreak of Oropouche fever on the island. The etiologic agent, Oropouche virus (OROV), is a poorly understood arbovirus that has been known since the 1960s and represents a public health burden in Latin America. We report the whole-genome characterization of the first European OROV isolate from a returning traveler from Cuba with Oropouche fever-like symptoms. The isolate was obtained from the patient's serum; whole-genome sequencing was performed by next-generation sequencing, followed by phylogenetic analysis and genetic variability studies. The analysis showed that the most closely related sequence was from the French Guiana 2020 outbreak. Interestingly, our isolate is a reassortant virus, included in a highly supported monophyletic clade containing recent OROV cases (Brazil 2015–Colombia 2021), separated from the other four previously known genotypes. More deeply, it was found to be included in a distinct branch containing the sequences of the Brazil 2022–2024 outbreak. The reassortment event involved the S and L segments, which have high similarity with sequences belonging to a new cluster (here defined as OROV_SCDC_2024), while the M segment shows high similarity with older sequences. These results likely describe the viral strain responsible for the current outbreak in Cuba, which may also reflect the ongoing outbreak in Latin America. Further studies are needed to understand how OROV evolves towards traits that facilitate its spread and adaptation outside its original basin, and to track its spread and evolution in the European continent. [ABSTRACT FROM AUTHOR]

In 2022, an unprecedented outbreak of mpox raged in several nations. Sequences from the 2022 outbreak reveal a higher nucleotide substitution if compared with the estimated rate for orthopoxviruses. Recently, intra-lesion SNVs (single nucleotide variants) have been described, and these have been suggested as possible sources of genetic variation. Until now, it has not been clear if the presence of several SNVs could represents the result of local mutagenesis or a possible co-infection. We investigated the significance of SNVs through whole-genome sequencing analysis of four unrelated mpox cases. In addition to the known mutations harboured by the circulating strains of virus (MPXV), 7 novel mutations were identified, including SNVs located in genes that are involved in immune evasion mechanisms and/or viral fitness, six of these appeared to be APOBEC3-driven. Interestingly, three patients exhibited the coexistence of mutated and wild-type alleles for five non-synonymous variants. In addition, two patients, apparently unrelated, showed an analogous pattern for two novel mutations, albeit with divergent frequencies. The coexistence of mixed viral populations, harbouring non-synonymous mutations in patients, supports the hypothesis of possible co-infection. Additional investigations of larger clinical cohorts are essential to validating intra-patient viral genome heterogeneity and determining the possibility of co-presence events of slightly divergent MPXV strains. [ABSTRACT FROM AUTHOR]

With the continuous spread of new SARS-CoV-2 variants of concern (VOCs), the monitoring of diagnostic test performances is mandatory. We evaluated the changes in antigen diagnostic tests' (ADTs) accuracy along the Delta to Omicron VOCs transition, exploring the N protein mutations possibly affecting ADT sensitivity and assessing the best sampling site for the diagnosis of Omicron infections. In total, 5175 subjects were enrolled from 1 October 2021 to 15 July 2022. The inclusion criteria were SARS-CoV-2 ADT combined with a same-day RT-PCR swab test. For the sampling site analysis, 61 patients were prospectively recruited during the Omicron period for nasal and oral swab analyses by RT-PCR. Next-Generation Sequencing data were obtained to evaluate the different sublineages. Using RT-PCR as a reference, 387 subjects resulted in becoming infected and the overall sensitivity of the ADT decreased from 63% in the Delta period to 33% in the Omicron period. This decrease was highly statistically significant (p < 0.001), and no decrease in viral load was detected at the RNA level. The nasal site presented a significantly higher viral load than the oral site during the Omicron wave. The reduced detection rate of Omicron infections by ADT should be considered in the global testing strategy to preserve accurate diagnoses across the changing SARS-CoV-2 variants. [ABSTRACT FROM AUTHOR]

The SARS-CoV-2 Delta variant of concern (VOC) was often associated with serious clinical course of the COVID-19 disease. Herein, we investigated the selective pressure, gene flow and evaluation on the frequencies of mutations causing amino acid substitutions in the Delta variant in three Italian regions. A total of 1500 SARS-CoV-2 Delta genomes, collected in Italy from April to October 2021 were investigated, including a subset of 596 from three Italian regions. The selective pressure and the frequency of amino acid substitutions and the prediction of their possible impact on the stability of the proteins were investigated. Delta variant dataset, in this study, identified 68 sites under positive selection: 16 in the spike (23.5%), 11 in nsp2 (16.2%) and 10 in nsp12 (14.7%) genes. Three of the positive sites in the spike were located in the receptor-binding domain (RBD). In Delta genomes from the three regions, 6 changes were identified as very common (>83.7%), 4 as common (>64.0%), 21 at low frequency (2.1%–25.0%) and 29 rare (≤2.0%). The detection of positive selection on key mutations may represent a model to identify recurrent signature mutations of the virus. [ABSTRACT FROM AUTHOR]

The article discusses the potential risks of Oropouche virus (OROV) importation into Europe due to increased global travel and climate change. OROV, primarily transmitted by Culicoides and other mosquitoes, has caused outbreaks in Central and South America, with the first cases reported outside of Latin America in Italy. The upcoming mass gathering events in Europe, such as the Olympic Games in Paris and the Jubilee in Rome, could facilitate the spread of OROV through human movements. The authors emphasize the need for surveillance, vector studies, and awareness among healthcare professionals to prevent the establishment of OROV transmission cycles in new regions. [Extracted from the article]

The immune response to invading pathogens is characterized by the rapid establishment of a complex network of cellular interactions and soluble signals. The correct balancing of activating and regulating pathways and tissue-homing signals determines its effectiveness and persistence over time. Emerging viral pathogens have always represented a great challenge to the immune system and an often uncontrolled/imbalanced immune response has been described (e.g. cytokine storm, immune paralysis), contributing to the severity of the disease. Several immune biomarkers and cell subsets have been identified as major players in the cascade of events leading to severe diseases, highlighting the rationale for host-directed intervention strategy. There are millions of immunocompromised pediatric and adult patients worldwide (e.g. transplant recipients, hematologic patients, subjects with primary immunedeficiencies), experiencing an impaired immune reactivity, due to diseases and/or to the medical treatments. The reduced immune reactivity could have two paradoxical non-exclusive effects: a weak protective immunity on one hand, and a reduced contribution to immune-mediated pathogenetic processes on the other hand. In these sensitive contexts, the impact of emerging infections represents a still open issue to be explored with several challenges for immunologists, virologists, physicians and epidemiologists. In this review, we will address emerging infections in immunocompromised hosts, to summarize the available data concerning the immune response profile, its influence on the clinical presentation, the possible contribution of persistent viral shedding in generating new viral variants with improved immune escape features, and the key role of vaccination. [ABSTRACT FROM AUTHOR]

The COVID‐19 pandemic has represented an unprecedented challenge for the humanity, and scientists around the world provided a huge effort to elucidate critical aspects in the fight against the pathogen, useful in designing public health strategies, vaccines and therapeutic approaches. One of the first pieces of evidence characterizing the SARS‐CoV‐2 infection has been its breadth of clinical presentation, ranging from asymptomatic to severe/deadly disease, and the indication of the key role played by the immune response in influencing disease severity. This review is aimed at summarizing what the SARS‐CoV‐2 infection taught us about the immune response, highlighting its features of a double‐edged sword mediating both protective and pathogenic processes. We will discuss the protective role of soluble and cellular innate immunity and the detrimental power of a hyper‐inflammation‐shaped immune response, resulting in tissue injury and immunothrombotic events. We will review the importance of B‐ and T‐cell immunity in reducing the clinical severity and their ability to cross‐recognize viral variants. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to characterize the genome of a recombinant Enterovirus associated with severe and fatal nosocomial infection; it was typed as Echovirus 11 (E-11) according to the VP1 gene. Enterovirus infection is generally asymptomatic and self-limited, but occasionally it may progress to a more severe clinical manifestation, as in the case described here. Recombination plays a crucial role in the evolution of Enteroviruses (EVs) and has been recognized as the main driving force behind the emergence of epidemic strains associated with severe infection. Therefore, it is of utmost importance to monitor the circulation of recombinant strains for surveillance purposes. Methods: Enterovirus-RNA was detected in the serum and liver biopsy of patients involved in the nosocomial cluster by commercial One-Step qRT-PCR method and the Enterovirus strains were isolated in vitro. The EVs typing was determined by analyzing the partial-length of the 5′UTR and VP1 sequences with the web-based open-access Enterovirus Genotyping Tool Version 0.1. The amplicons targeting 5′UTR, VP1 and overlapping fragments of the entire genome were sequenced with the Sanger method. Phylogenetic analysis was performed comparing the VP1 and the full-genome sequences of our strains against an appropriate reference set of Enterovirus prototypes of the Picornaviridae genera and species retrieved from the Enterovirus Genotyping Tool. Recombination analysis was performed using RDP4 software. Results: The Neighbor-Joining tree of the VP1 gene revealed that the 4 patients were infected with an identical molecular variant of Echovirus 11 (E-11). While the phylogenetic and the RDP4 analysis of the full-genome sequences provided evidence that it was a chimeric strain between an E-11 and a Coxsackievirus B (CV-B). Conclusions: The chimeric structure of the E-11 genome might have contributed to the severe infection and epidemic feature of the strain, but further biological characterizations are needed. The evidence reported in this study, highlights the limit of typing techniques based on the VP1 gene, as they fail to identify the emergence of recombinant strains with potentially more pathogenic or epidemic properties, thus providing only partial information on the epidemiology and pathogenesis of Enteroviruses. [ABSTRACT FROM AUTHOR]

Progressive Multifocal Leukoencephalopathy (PML) is a demyelinating disease occurring in advanced HIV infection, caused by the reactivation of poliomavirus JC (JCV). The use of pembrolizumab for treatment is based on the inhibition of programmed cell death protein 1 (PD-1), potentially improving the anti JCV-specific response. We used pembrolizumab with combined antiretroviral treatment (cART) on a compassionate-use basis. At each administration, clinical evaluation, MRI and laboratory testing, including CD3, CD4, CD8, PD-1 markers, HIV-RNA and JCV-DNA in cerebrospinal fluid (CSF)/plasma pairs, were performed. The JCV-specific T cell response was analysed by Elispot assay. This study included five HIV patients: four male, median age 43 years (29–52), median CD4 and CD8 count 150 (15–158) and 973 (354–1250) cell/mm3, respectively; median JCV-DNA and HIV-RNA in CSF/plasma pairs 9.540/1.503 cps/mL and 2.230/619 cp/mL, respectively. Overall, patients received between two and seven doses of pembrolizumab. After treatment, we observed JCV-DNA reduction and PD-1 down-regulation both in CSF and in plasma (high in circulating CD4 and CD8 at baseline), which remained stable at low levels in all patients. Three out of five patients showed stability of clinical picture and neuroimaging, while two others died. More data are needed in order to identify predictors of response to therapy. [ABSTRACT FROM AUTHOR]

Vaccine is the main public health measure to reduce SARS-CoV-2 transmission and hospitalization, and a massive scientific effort worldwide resulted in the rapid development of effective vaccines. This work aimed to define the dynamics and persistence of humoral and cell-mediated immune response in Health Care Workers who received a two-dose BNT162b2-mRNA vaccination. Serological response was evaluated by quantifying anti-RBD and neutralizing antibodies while cell-mediated response was performed by a whole blood test quantifying Th1 cytokines (IFN-γ, TNF-α, IL-2) produced in response to Spike peptides. BNT162b2-mRNA vaccine induced both humoral and cell-mediated immune response against Spike in all HCW early after the second dose. After 12 weeks from vaccination, the titer of anti-RBD antibodies as well as their neutralization function decreased while the Spike-specific T-cells persisted at the same level as soon after vaccine boost. Of note, a correlation between cellular and humoral response persevered, suggesting the persistence of a coordinated immune response. The long lasting cell-mediated immune response after 3 months from vaccination highlight its importance in the maintaining of specific immunity able to expand again to fight eventual new antigen encountering. [ABSTRACT FROM AUTHOR]

The optimal therapeutic approach for primary HIV infection (PHI) is still debated. We aimed to compare the viroimmunological response to a four- versus a three-drug regimen, both INSTI-based, in patients with PHI. This was a monocentric, prospective, observational study including all patients diagnosed with PHI from December 2014 to April 2018. Antiretroviral therapy (ART) was started, before genotype resistance test results, with tenofovir/emtricitabine and either raltegravir plus boosted darunavir or dolutegravir. Cumulative probability of virological suppression [VS] (HIV-1 RNA< 40 cp/mL), low-level HIV-1 DNA [LL-HIVDNA] (HIV-1 DNA < 200 copies/106PBMC), and CD4/CD8 ratio ≥1 were estimated using Kaplan–Meier curves. Factors associated with the achievement of VS, LL-HIVDNA, and CD4/CD8 ≥ 1 were assessed by a Cox regression model. We enrolled 144 patients (95.8% male, median age 34 years): 110 (76%) started a four-drug-based therapy, and 34 (24%) a three-drug regimen. Both treatment groups showed a comparable high probability of achieving VS and a similar probability of reaching LL-HIVDNA and a CD4/CD8 ratio ≥1 after 48 weeks from ART initiation. Higher baseline HIV-1 RNA and HIV-1 DNA levels lowered the chance of VS, whereas a better preserved immunocompetence increased that chance. Not statistically significant factors associated with LL-HIVDNA achievement were found, whereas a higher baseline CD4/CD8 ratio predicted the achievement of immune recovery. In PHI patients, the rapid initiation of either an intensified four-drug or a standard three-drug INSTI-based regimen showed comparable responses in terms of VS, viral reservoir size, and immunological recovery. [ABSTRACT FROM AUTHOR]

We report detecting infectious Toscana virus in the seminal fluid of a 25-year-old man from Italy returning from Elba Island. The presence of infectious virus in human semen adds Toscana virus to the long list of viruses detected in this genital fluid and indicates a potential for sexual transmission. [ABSTRACT FROM AUTHOR]

Except for specific vaccines and monoclonal antibodies, effective prophylactic or post-exposure therapeutic treatments are currently limited for COVID-19. Propolis, a honeybee's product, has been suggested as a potential candidate for treatment of COVID-19 for its immunomodulatory properties and for its powerful activity against various types of viruses, including common coronaviruses. However, direct evidence regarding the antiviral activities of this product still remains poorly documented. VERO E6 and CALU3 cell lines were infected with SARS-CoV-2 and cultured in the presence of 12.5 or 25 μg/ml of a standardized Hydroalcoholic Extract acronym (sHEP) of Eurasian poplar type propolis and analyzed for viral RNA transcription, for cell damage by optical and electron microscopy, and for virus infectivity by viral titration at 2, 24, 48, and 72 h post-infection. The three main components of sHEP, caffeic acid phenethyl ester, galangin, and pinocembrin, were tested for the antiviral power, either alone or in combination. On both cell lines, sHEP showed significant effects mainly on CALU3 up to 48 h, i.e., some protection from cytopathic effects and consistent reduction of infected cell number, fewer viral particles inside cellular vesicles, reduction of viral titration in supernatants, dramatic drop of N gene negative sense RNA synthesis, and lower concentration of E gene RNA in cell extracts. Interestingly, pre-treatment of cells with sHEP before virus inoculation induced these same effects described previously and was not able to block virus entry. When used in combination, the three main constituents of sHEP showed antiviral activity at the same levels of sHEP. sHEP has a remarkable ability to hinder the replication of SARS-CoV-2, to limit new cycles of infection, and to protect host cells against the cytopathic effect, albeit with rather variable results. However, sHEP do not block the virus entry into the cells. The antiviral activity observed with the three main components of sHEP used in combination highlights that the mechanism underlying the antiviral activity of sHEP is probably the result of a synergistic effect. These data add further emphasis on the possible therapeutic role of this special honeybee's product as an adjuvant to official treatments of COVID-19 patients for its direct antiviral activity. [ABSTRACT FROM AUTHOR]

Introduction: Transplantation among HIV positive patients may be a valuable therapeutic intervention. This study involves an HIV D+/R+ kidney–liver transplantation, where PBMC-associated HIV quasispecies were analyzed in donor and transplant recipients (TR) prior to transplantation and thereafter, together with standard viral monitoring. Methods: The donor was a 54 year of age HIV infected woman: kidney and liver recipients were two HIV infected men, aged 49 and 61. HIV quasispecies in PBMC was analyzed by ultra-deep sequencing of V3 env region. During TR follow-up, plasma HIV-1 RNA, HIV-1 DNA in PBMC, analysis of proviral integration sites and drug-resistance genotyping were performed. Other virological and immunological monitoring included CMV and EBV DNA quantification in blood and CD4 T cell counts. Results: Donor and TR were all ART-HIV suppressed at transplantation. Thereafter, TR maintained a nearly suppressed HIV-1 viremia, but HIV-1 RNA blips and the increase of proviral integration sites in PBMC attested some residual HIV replication. A transient peak in HIV-1 DNA occurred in the liver recipient. No major changes of drug-resistance genotype were detected after transplantation. CMV and EBV transient reactivations were observed only in the kidney recipient, but did not require specific treatment. CD4 counts remained stable. No intermixed quasispecies between donor and TR was observed at transplantation or thereafter. Despite signs of viral evolution in TR, HIV genetic heterogeneity did not increase over the course of the months of follow up. Conclusions: No evidence of HIV superinfection was observed in the donor nor in the recipients. The immunosuppressive treatment administrated to TR did not result in clinical relevant viral reactivations. [ABSTRACT FROM AUTHOR]

Background: Early sequencing and quick analysis of the SARS-CoV-2 genome have contributed to the understanding of the dynamics of COVID-19 epidemics and in designing countermeasures at a global level. Objective: Amplicon-based next-generation sequencing (NGS) methods are widely used to sequence the SARS-CoV-2 genome and to identify novel variants that are emerging in rapid succession as well as harboring multiple deletions and amino acid–changing mutations. Methods: To facilitate the analysis of NGS sequencing data obtained from amplicon-based sequencing methods, here, we propose an easy-to-use SARS-CoV-2 genome assembler: the Easy-to-use SARS-CoV-2 Assembler (ESCA) pipeline. Results: Our results have shown that ESCA could perform high-quality genome assembly from Ion Torrent and Illumina raw data and help the user in easily correct low-coverage regions. Moreover, ESCA includes the possibility of comparing assembled genomes of multisample runs through an easy table format. Conclusions: In conclusion, ESCA automatically furnished a variant table output file, fundamental to rapidly recognizing variants of interest. Our pipeline could be a useful method for obtaining a complete, rapid, and accurate analysis even with minimal knowledge in bioinformatics. [ABSTRACT FROM AUTHOR]

Background: Omics data, driven by rapid advances in laboratory techniques, have been generated very quickly during the COVID-19 pandemic. Our aim is to use omics data to highlight the involvement of specific pathways, as well as that of cell types and organs, in the pathophysiology of COVID-19, and to highlight their links with clinical phenotypes of SARS-CoV-2 infection.Methods: The analysis was based on the domain model, where for domain it is intended a conceptual repository, useful to summarize multiple biological pathways involved at different levels. The relevant domains considered in the analysis were: virus, pathways and phenotypes. An interdisciplinary expert working group was defined for each domain, to carry out an independent literature scoping review.Results: The analysis revealed that dysregulated pathways of innate immune responses, (i.e., complement activation, inflammatory responses, neutrophil activation and degranulation, platelet degranulation) can affect COVID-19 progression and outcomes. These results are consistent with several clinical studies.Conclusions: Multi-omics approach may help to further investigate unknown aspects of the disease. However, the disease mechanisms are too complex to be explained by a single molecular signature and it is necessary to consider an integrated approach to identify hallmarks of severity. [ABSTRACT FROM AUTHOR]

The Interferon (IFN) response is crucial to restrain pathogenic infections. Investigations into flavivirus-host interactions reported that the high virulence is linked to innate immune evasion. Zika Virus (ZIKV) has developed diversified strategies to evade the innate immune system. We report that the viral protein NS2A counteracts the IFN response by strongly suppressing the IFN signaling. NS2A targets transcription factors STAT1 and STAT2, to impede their nuclear localization, thereby suppressing the transcription of ISRE promoter and IFN-stimulated genes. We found that NS2A promotes degradation of STAT1 and STAT2. Treatment of NS2A transfected cells with MG132 restores the levels of both transcription factors, suggesting the involvement of the proteasome system. Given the impact that the IFN antagonism has on flavivirus virulence, the knowledge gained by characterizing the mechanism through which ZIKV evades the IFN response paves the ground for new strategies to attenuate the pathogenesis and to develop countermeasures against effective pharmacological targets. [ABSTRACT FROM AUTHOR]

Background: Several biomarkers have been identified to predict the outcome of COVID-19 severity, but few data are available regarding sex differences in their predictive role. Aim of this study was to identify sex-specific biomarkers of severity and progression of acute respiratory distress syndrome (ARDS) in COVID-19. Methods: Plasma levels of sex hormones (testosterone and 17β-estradiol), sex-hormone dependent circulating molecules (ACE2 and Angiotensin1-7) and other known biomarkers for COVID-19 severity were measured in male and female COVID-19 patients at admission to hospital. The association of plasma biomarker levels with ARDS severity at admission and with the occurrence of respiratory deterioration during hospitalization was analysed in aggregated and sex disaggregated form. Results: Our data show that some biomarkers could be predictive both for males and female patients and others only for one sex. Angiotensin1-7 plasma levels and neutrophil count predicted the outcome of ARDS only in females, whereas testosterone plasma levels and lymphocytes counts only in males. Conclusions: Sex is a biological variable affecting the choice of the correct biomarker that might predict worsening of COVID-19 to severe respiratory failure. The definition of sex specific biomarkers can be useful to alert patients to be safely discharged versus those who need respiratory monitoring. [ABSTRACT FROM AUTHOR]

Simple and standardized methods to establish correlates to vaccine-elicited SARS-CoV-2 protection are needed. An observational study on antibody response to a mRNA vaccine (Comirnaty) was performed on health care workers (V, n=120). Recovered COVID-19 patients (N, n=94) were used for comparison. Antibody response was evaluated by a quantitative anti-receptor binding domain IgG (anti-RBD) commercial assay and by virus microneutralization test (MNT), in order to establish a threshold of anti-RBD binding antibody units (BAU) able to predict a robust (≥1:80) MNT titer. Significant correlation between BAU and MNT titers was found in both V and N, being stronger in V (rs=0.91 and 0.57 respectively, p<0.001); a higher incremental trend starting from MNT titer 1:80 was observed in the V group. The 99% probability of high MNT titer (≥1:80) was reached at 1,814 and 3,564 BAU/mL, and the area under the receiver operating characteristic (ROC) curve was 0.99 (CI: 0.99–1.00) and 0.78 (CI: 0.67–0.86) in V and N, respectively. A threshold of 2,000 BAU/mL is highly predictive of strong MNT response in vaccinated individuals and may represent a good surrogate marker of protective response. It remains to be established whether the present results can be extended to BAU titers obtained with other assays. [ABSTRACT FROM AUTHOR]

In response to the rapidly evolving of SARS-CoV-2 infection, numerous serological tests have been developed but their sensitivity and specificity are unclear. We collected serum samples of patients and health-care professionals to assess the accuracy of chemiluminescent (CLIA) and two lateral flow immunochromatographic assays (LFIA) to determine IgG and IgM antibodies to SARS-CoV-2 virus. We calculated the φ correlation for qualitative results and test accuracy, adopting the following case definition: either real-time-PCR positivity or serological positivity with at least two different tests. We analyzed 259 samples, obtaining strong correlation between CLIA and both LFIA for IgG (φ=0.9), and moderate correlation for IgM (φ=0.6). For patients, the sensitivity was suboptimal for all methods (CLIA 81%, LFIA A 85%, LFIA B 78%), while it was poor in asymptomatic health-care workers (CLIA 50%, LFIA A 50%, LFIA B 33%). Overall, CLIA is more sensitive and specific for the determination of both IgG and IgM, whilst both LFIA methods reported good sensitivity and specificity for IgG, but scarce sensitivity for the IgM determination. The determination of SARS-CoV-2-specific IgG is useful to detect infection 6 days from symptom onset. [ABSTRACT FROM AUTHOR]

We report a case of myopericarditis associated to SARS-CoV-2 infection with necrotizing coronary vasculitis of intramural vessels, giving rise to biventricular apical microaneurysms and to electrical instability. Negativity of myocardial polymerase chain reaction for the most common cardiotropic viruses and for SARS-CoV-2 suggested an immune-mediated myocardial and pericardial inflammatory disease. High dose (1 mg/Kg daily) prednisone and anti-viral (Remdesivir, IDA Business, Carrigtohill, County Cork, T45 DP77, Ireland) therapy led to resolution of cardiac inflammation and ventricular arrhythmias. Morpho-molecular characterization of endomyocardial tissue may improve the outcome in subjects with SARS-CoV-2-associated myopericarditis and coronary vasculitis. [ABSTRACT FROM AUTHOR]

Compared to RT-PCR, lower performance of antigen detection assays, including the Lumipulse G SARS-CoV-2 Ag assay, may depend on specific testing scenarios. We tested 594 nasopharyngeal swab samples from individuals with COVID-19 (RT-PCR cycle threshold [Ct] values ≤ 40) or non-COVID-19 (Ct values >40) diagnoses. RT-PCR positive samples were assigned to diagnostic, screening, or monitoring groups of testing. With a limit of detection of 1.2 × 104 SARS-CoV-2 RNA copies/mL, Lumipulse showed positive percent agreement (PPA) of 79.9% (155/194) and negative percent agreement of 99.3% (397/400), whereas PPAs were 100% for samples with Ct values of <18 or 18–<25 and 92.5% for samples with Ct values of 25–<30. By three groups, Lumipulse showed PPA of 87.0% (60/69), 81.1% (43/53), or 72.2% (52/72), respectively, whereas PPA was 100% for samples with Ct values of <18 or 18–<25, and was 94.4, 80.0, or 100% for samples with Ct values of 25–<30, respectively. Additional testing of RT-PCR positive samples for SARS-CoV-2 subgenomic RNA showed that, by three groups, PPA was 63.8% (44/69), 62.3% (33/53), or 33.3% (24/72), respectively. PPAs dropped to 55.6, 20.0, or 41.7% for samples with Ct values of 25–<30, respectively. All 101 samples with a subgenomic RNA positive result had a Lumipulse assay's antigen positive result, whereas only 54 (58.1%) of remaining 93 samples had a Lumipulse assay's antigen positive result. Lumipulse assay was highly sensitive in samples with low RT-PCR Ct values, implying repeated testing to reduce consequences of false-negative results. [ABSTRACT FROM AUTHOR]

Coronaviruses (CoVs) are enveloped nonsegmented positive-sense RNA viruses belonging to the family Coronaviridae that contain the largest genome among RNA viruses. Their genome encodes 4 major structural proteins, and among them, the Spike (S) protein plays a crucial role in determining the viral tropism. It mediates viral attachment to the host cell, fusion to the membranes, and cell entry using cellular proteases as activators. Several in vitro models have been developed to study the CoVs entry, pathogenesis, and possible therapeutic approaches. This article is aimed at summarizing the current knowledge about the use of relevant methodologies and cell lines permissive for CoV life cycle studies. The synthesis of this information can be useful for setting up specific experimental procedures. We also discuss different strategies for inhibiting the binding of the S protein to the cell receptors and the fusion process which may offer opportunities for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Aims Patients with severe respiratory syndrome caused by SARS-CoV-2 undergo cardiac complications due to hyper-inflammatory conditions. Although the presence of the virus has been detected in the myocardium of infected patients, and infection of induced pluripotent cell-derived cardiomyocytes has been demonstrated, the reported expression of Angiotensin-Converting Enzyme-2 (ACE2) in cardiac stromal cells suggests that SARS-CoV-2 may determine cardiac injury by sustaining productive infection and increasing inflammation. Methods and results  We analysed expression of ACE2 receptor in primary human cardiac stromal cells derived from cardiospheres, using proteomics and transcriptomics before exposing them to SARS-CoV-2 in vitro. Using conventional and high sensitivity PCR methods, we measured virus release in the cellular supernatants and monitored the intracellular viral bioprocessing. We performed high-resolution imaging to show the sites of intracellular viral production and demonstrated the presence of viral particles in the cells with electron microscopy. We finally used RT–qPCR assays to detect genes linked to innate immunity and fibrotic pathways coherently regulated in cells after exposure to the virus. Conclusions  Our findings indicate that cardiac stromal cells are susceptible to SARS-CoV-2 infection and produce variable viral yields depending on the extent of cellular ACE2 receptor expression. Interestingly, these cells also evolved towards hyper-inflammatory/pro-fibrotic phenotypes independently of ACE2 levels. Thus, SARS-CoV-2 infection of myocardial stromal cells could be involved in cardiac injury and explain the high number of complications observed in severe cases of COVID-19. [ABSTRACT FROM AUTHOR]

Prophylactic low molecular weight heparin (pLMWH) is currently recommended in COVID-19 to reduce the risk of coagulopathy. The aim of this study was to evaluate whether the antinflammatory effects of pLMWH could translate in lower rate of clinical progression in patients with COVID-19 pneumonia. Patients admitted to a COVID-hospital in Rome with SARS-CoV-2 infection and mild/moderate pneumonia were retrospectively evaluated. The primary endpoint was the time from hospital admission to orotracheal intubation/death (OTI/death). A total of 449 patients were included: 39% female, median age 63 (IQR, 50–77) years. The estimated probability of OTI/death for patients receiving pLMWH was: 9.5% (95% CI 3.2–26.4) by day 20 in those not receiving pLMWH vs. 10.4% (6.7–15.9) in those exposed to pLMWH; p-value = 0.144. This risk associated with the use of pLMWH appeared to vary by PaO2/FiO2 ratio: aHR 1.40 (95% CI 0.51–3.79) for patients with an admission PaO2/FiO2 ≤ 300 mmHg and 0.27 (0.03–2.18) for those with PaO2/FiO2 > 300 mmHg; p-value at interaction test 0.16. pLMWH does not seem to reduce the risk of OTI/death mild/moderate COVID-19 pneumonia, especially when respiratory function had already significantly deteriorated. Data from clinical trials comparing the effect of prophylactic vs. therapeutic dosage of LMWH at various stages of COVID-19 disease are needed. [ABSTRACT FROM AUTHOR]

Little evidence on coronavirus disease 2019 (COVID‐19) in people living with HIV (PLWH) is currently available. We reported clinical and viroimmunological data of all HIV‐positive patients admitted to our center with COVID‐19 from March 1 to May 12, 2020. Overall, five patients were included: all were virologically‐suppressed on antiretroviral therapy and CD4+ count was greater than 350 cell/mm3 in all but two patients. Although all patients had evidence of pneumonia on admission, only one developed respiratory failure. Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) RNA was never detected from nasopharyngeal swabs in two patients, whereas in the others, viral clearance occurred within a maximum of 43 days. Immunoglobulin G production was elicited in all patients and neutralizing antibodies in all but one patient. Specific‐T‐cell response developed in all patients but was stronger in those with the more severe presentations. Similarly, the highest level of proinflammatory cytokines was found in the only patient experiencing respiratory failure. Despite a mild presentation, patients with more pronounced immunosuppression showed high degrees of both cytokines production and immune activation. Our study did not find an increased risk and severity of COVID‐19 in PLWH. Adaptative cellular immune response to SARS‐CoV‐2 appeared to correlate to disease severity. The mild clinical picture showed in advanced HIV patients, despite a significant T‐cell activation and inflammatory profile, suggests a potential role of HIV‐driven immunological dysregulation in avoiding immune‐pathogenetic processes. However, other possible explanations, as a protective role of certain antiretroviral drugs, should be considered. Further larger studies are needed to better clarify the impact of HIV infection on COVID‐19. Highlights: The clinical course of COVID‐19 and the dynamics of the immune response to SARS‐CoV‐2 infection in people living with HIV have not yet been fully elucidated Indeed, although worse outcomes might be expected in HIV‐positive patients compared to the general population, it has been supposed that the HIV‐related immune dysregulation could paradoxically mitigate the hyperinflammation syndrome responsible for the most severe complications of SARS‐CoV‐2 infection.In this case series we did not find an increased risk of both acquiring and having a severe course of COVID‐19 in people living with HIV compared to how reported in the general population.We observed that patients with more severe HIV‐related immunosuppression, despite the development of a specific immune response and the presence of a strong cellular immune‐activation and a moderate inflammatory profile, experienced a mild/moderate disease. These findings might suggest that the lower and impaired immune reactivity of advanced HIV infection could contribute to avoid immune‐pathogenetic processes. However, other possible explanations, as a potential protective role of certain antiretroviral regimens, should be considered. [ABSTRACT FROM AUTHOR]

COronaVIrus Disease-2019 (COVID-19) is a pandemic respiratory infection caused by a new betacoronavirus, the Severe Acute Respiratory Syndrome-CoronaVirus-2 (SARS-CoV-2). Few data are reported on the gut microbiota in COVID-19 patients. 16S rRNA gene sequencing was performed to reveal an altered composition of the gut microbiota in patients with COVID-19 pneumonia admitted in intensive care unit (ICU) (i-COVID19), or in infectious disease wards (w-COVID19) as compared to controls (CTRL). i-COVID19 patients showed a decrease of Chao1 index as compared to CTRL and w-COVID19 patients indicating that patients in ICU displayed a lower microbial richness while no change was observed as for Shannon Index. At the phylum level, an increase of Proteobacteria was detected in w-COVID19 patients as compared to CTRL. A decrease of Fusobacteria and Spirochetes has been found, with the latter decreased in i-COVID19 patients as compared to CTRL. Significant changes in gut microbial communities in patients with COVID-19 pneumonia with different disease severity compared to CTRL have been identified. Our preliminary data may provide valuable information and promising biomarkers for the diagnosis of the disease and, when validated in larger cohort, it could facilitate the stratification of patients based on the microbial signature. [ABSTRACT FROM AUTHOR]

We report phylogenetic and mutational analysis by NGS of six SARS-CoV-2 strains from patients flying from Bangladesh to Italy (July 2020). Data suggest that no further circulation of such imported strains occurred in Italy, stating the efficacy of early screening at the point of entry and supporting the importance of molecular epidemiology in monitoring the efficacy of control measures. [ABSTRACT FROM AUTHOR]

The Interferon (IFN) response is crucial to restrain pathogenic infections. Investigations into flavivirus-host interactions reported that the high virulence is linked to innate immune evasion. Zika Virus (ZIKV) has developed diversified strategies to evade the innate immune system. We report that the viral protein NS2A counteracts the IFN response by strongly suppressing the IFN signaling. NS2A targets transcription factors STAT1 and STAT2, to impede their nuclear localization, thereby suppressing the transcription of ISRE promoter and IFN-stimulated genes. We found that NS2A promotes degradation of STAT1 and STAT2. Treatment of NS2A transfected cells with MG132 restores the levels of both transcription factors, suggesting the involvement of the proteasome system. Given the impact that the IFN antagonism has on flavivirus virulence, the knowledge gained by characterizing the mechanism through which ZIKV evades the IFN response paves the ground for new strategies to attenuate the pathogenesis and to develop counter-measures against effective pharmacological targets. [ABSTRACT FROM AUTHOR]

Background: Coronavirus disease 2019 (COVID-19) is mainly a respiratory tract disease and acute respiratory failure with diffuse microvascular pulmonary thrombosis are critical aspects of the morbidity and mortality of this new syndrome. Purpose: The aim of our study was to investigate, in severe COVID-19 hospitalized patients, the P-selectin plasma concentration as a biomarker of endothelial dysfunction and platelet activation. Methods: 46 patients with severe or critical SARS-CoV-2 infection were included in the study. Age-matched patients then were divided in those requiring admission to the intensive care unit (ICU, ICU cases) vs those not requiring ICU hospitalization (non-ICU cases). Blood samples of severe COVID-19 patients were collected at the time of hospital admission. The quantification of soluble P-selectin was performed by ELI, assay. Results: Our study showed a higher P-selectin plasma concentration in patients with Covid-19, regardless of ICU admission, compared to the normal reference values and compared to ten contextually sampled healthy donors (HD); (COVID-19): median 65.2 (IQRs: 45.1-81.1) vs. HD: 40.3 (IQRs: 24.3-48.7), p=0023. Moreover, results showed a significant reduction of P-sele din after platelets removal in HD, in contrast, both ICU and non-ICU COVID-19 patients showed similar high levels of P-selectin with and without platelets. Conclusion: Elevation of P-selectin suggests a central role of platelet endothelium interaction as part of the multifaced pathogenic mechanism of COVID-19 leading to the local activation of hemostatic system forming pulmonary thrombi. Further work is necessary to determine the therapeutic role of antiplatelets agents or of the anti P-selectin antibody Crizanlizumab. [ABSTRACT FROM AUTHOR]

Non-nonavalent vaccine (9v) Human papillomavirus (HPV) types have been shown to have high prevalence among HIV-positive women. Here, 1444 cervical samples were tested for HPV DNA positivity. Co-infections of the 9v HPV types with other HPV types were evaluated. The HPV81 L1 and L2 genes were used to investigate the genetic variability of antigenic epitopes. HPV-positive samples were genotyped using the HPVCLART2 assay. The L1 and L2 protein sequences were analyzed using a self-optimized prediction method to predict their secondary structure. Co-occurrence probabilities of the 9v HPV types were calculated. Non9v types represented 49% of the HPV infections; 31.2% of the non9v HPV types were among the low-grade squamous intraepithelial lesion samples, and 27.3% among the high-grade squamous intraepithelial lesion samples, and several genotypes were low risk. The co-occurrence of 9v HPV types with the other genotypes was not correlated with the filogenetic distance. HPV81 showed an amino-acid substitution within the BC loop (N75Q) and the FGb loop (T315N). In the L2 protein, all of the mutations were located outside antigenic sites. The weak cross-protection of the 9v types suggests the relevance of a sustainable and effective screening program, which should be implemented by HPV DNA testing that does not include only high-risk types. [ABSTRACT FROM AUTHOR]

Background: Remdesivir is a prodrug of the nucleoside analogue GS-441524 and is under evaluation for treatment of SARS-CoV-2-infected patients.Objectives: To evaluate the pharmacokinetics of remdesivir and GS-441524 in plasma, bronchoalveolar aspirate (BAS) and CSF in two critically ill COVID-19 patients.Methods: Remdesivir was administered at 200 mg loading dose on the first day followed by 12 days of 100 mg in two critically ill patients. Blood samples were collected immediately after (C0) and at 1 (C1) and 24 h (C24) after intravenous administration on day 3 until day 9. BAS samples were collected on Days 4, 7 and 9 from both patients while one CSF on Day 7 was obtained in one patient. Remdesivir and GS-441524 concentrations were measured in these samples using a validated UHPLC-MS/MS method.Results: We observed higher concentrations of remdesivir at C0 (6- to 7-fold higher than EC50 from in vitro studies) and a notable decay at C1. GS-441524 plasma concentrations reached a peak at C1 and persisted until the next administration. Higher concentrations of GS-441524 were observed in the patient with mild renal dysfunction. Mean BAS/plasma concentration ratios of GS-441524 were 2.3% and 6.4% in Patient 1 and Patient 2, respectively. The CSF concentration found in Patient 2 was 25.7% with respect to plasma. GS-441524 levels in lung and CNS suggest compartmental differences in drug exposure.Conclusions: We report the first pharmacokinetic evaluation of remdesivir and GS-441524 in recovered COVID-19 patients. Further study of the pharmacokinetic profile of remdesivir, GS-441524 and the intracellular triphosphate form are required. [ABSTRACT FROM AUTHOR]

Background The pathogenesis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remains unclear. We report the detection of viral RNA from different anatomical districts and the antibody profile in the first 2 COVID-19 cases diagnosed in Italy. Methods We tested for SARS-CoV-2 RNA clinical samples, either respiratory and nonrespiratory (ie, saliva, serum, urine, vomit, rectal, ocular, cutaneous, and cervico-vaginal swabs), longitudinally collected from both patients throughout the hospitalization. Serological analysis was carried out on serial serum samples to evaluate IgM, IgA, IgG, and neutralizing antibody levels. Results SARS-CoV-2 RNA was detected since the early phase of illness, lasting over 2 weeks in both upper and lower respiratory tract samples. Virus isolate was obtained from acute respiratory samples, while no infectious virus was rescued from late respiratory samples with low viral RNA load, collected when serum antibodies had been developed. Several other specimens came back positive, including saliva, vomit, rectal, cutaneous, cervico-vaginal, and ocular swabs. IgM, IgA, and IgG were detected within the first week of diagnosis, with IgG appearing earlier and at higher titers. Neutralizing antibodies developed during the second week, reaching high titers 32 days after diagnosis. Conclusions Our longitudinal analysis showed that SARS-CoV-2 RNA can be detected in different body samples, which may be associated with broad tropism and different spectra of clinical manifestations and modes of transmission. Profiling antibody response and neutralizing activity can assist in laboratory diagnosis and surveillance actions. [ABSTRACT FROM AUTHOR]

We report phylogenetic and mutational analysis of severe acute respiratory syndrome coronavirus 2 virus strains from the Lazio region of Italy and provide information about the dynamics of virus spread. Data suggest effective containment of clade V strains, but subsequently, multiple waves of clade G strains were circulating widely in Europe. [ABSTRACT FROM AUTHOR]

Background: Epidemiological, virological and pathogenetic characteristics of SARS-CoV-2 infection are under evaluation. A better understanding of the pathophysiology associated with COVID-19 is crucial to improve treatment modalities and to develop effective prevention strategies. Transcriptomic and proteomic data on the host response against SARS-CoV-2 still have anecdotic character; currently available data from other coronavirus infections are therefore a key source of information.Methods: We investigated selected molecular aspects of three human coronavirus (HCoV) infections, namely SARS-CoV, MERS-CoV and HCoV-229E, through a network based-approach. A functional analysis of HCoV-host interactome was carried out in order to provide a theoretic host-pathogen interaction model for HCoV infections and in order to translate the results in prediction for SARS-CoV-2 pathogenesis. The 3D model of S-glycoprotein of SARS-CoV-2 was compared to the structure of the corresponding SARS-CoV, HCoV-229E and MERS-CoV S-glycoprotein. SARS-CoV, MERS-CoV, HCoV-229E and the host interactome were inferred through published protein-protein interactions (PPI) as well as gene co-expression, triggered by HCoV S-glycoprotein in host cells.Results: Although the amino acid sequences of the S-glycoprotein were found to be different between the various HCoV, the structures showed high similarity, but the best 3D structural overlap shared by SARS-CoV and SARS-CoV-2, consistent with the shared ACE2 predicted receptor. The host interactome, linked to the S-glycoprotein of SARS-CoV and MERS-CoV, mainly highlighted innate immunity pathway components, such as Toll Like receptors, cytokines and chemokines.Conclusions: In this paper, we developed a network-based model with the aim to define molecular aspects of pathogenic phenotypes in HCoV infections. The resulting pattern may facilitate the process of structure-guided pharmaceutical and diagnostic research with the prospect to identify potential new biological targets. [ABSTRACT FROM AUTHOR]

In Europe HAV infection occurs mainly among specific risk groups, such as consumers of specific food. Sexual transmission of HAV has been demonstrated, particularly among Men-Who-Have-Sex-With-Men (MSM), causing MSM-specific outbreaksin Europe. Here we report a molecular epidemiologic and phylodynamic analysis on HAV sequences in Lazio (central Italy)to identify genetic background and the phylogenetic relations, and test the HAV infection dynamics during a large outbreak through phylodynamic model.Among all HAV sequences found during 2013–2018 in Lazio, low genetic diversity was observed in HAV population in 2016 and 2017, along with high frequenciesVRD_521_2016and RIVM-HAV16-090, suggesting a large expansion event of viral population. The initial expansion of both VRD_521_2016 and RIVM-HAV16-090 clusters dated back to 2012 (95% HPD:2006–2015). During the2016-2017outbreak in Lazio region, the Re peaked around mid-2016, with a value of 1.73 (95% HPD: 1.03–2.37), consistent with incidence trend of AHA cases in Lazio between 2016 and mid-2017. This study showed the magnitude of HAV outbreak in Lazio during 2016–2017, demonstrating the epidemic continuity to MSM-specific outbreak in Europe. The HAV dataset is available on interactive phylodynamic platform https://nextstrain.org to real-time update of future outbreaks. [ABSTRACT FROM AUTHOR]

Human papillomavirus (HPV) is the most common sexually transmitted virus. The high-risk HPV types (i.e., HPV16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59) are considered to be the main etiological agents of genital tract cancers, such as cervical, vulvar, vaginal, penile, and anal cancers, and of a subset of head and neck cancers. Three prophylactic HPV vaccines are available that are bivalent (vs. HPV16, 18), tetravalent (vs. HPV6, 11, 16, 18), and non-avalent (vs. HPV6, 11, 16, 18, 31, 33,45, 52, 58). All of these vaccines are based on recombinant DNA technology, and they are prepared from the purified L1 protein that self-assembles to form the HPV type-specific empty shells (i.e., virus-like particles). These vaccines are highly immunogenic and induce specific antibodies. Therapeutic vaccines differ from prophylactic vaccines, as they are designed to generate cell-mediated immunity against transformed cells, rather than neutralizing antibodies. Among the HPV proteins, the E6 and E7 oncoproteins are considered almost ideal as targets for immunotherapy of cervical cancer, as they are essential for the onset and evolution of malignancy and are constitutively expressed in both premalignant and invasive lesions. Several strategies have been investigated for HPV therapeutic vaccines designed to enhance CD4+ and CD8+ T-cell responses, including genetic vaccines (i.e., DNA/ RNA/virus/ bacterial), and protein-based, peptide-based or dendritic-cell-based vaccines. However, no vaccine has yet been licensed for therapeutic use. Several studies have suggested that administration of prophylactic vaccines immediately after surgical treatment of CIN2 cervical lesions can be considered as an adjuvant to prevent reactivation or reinfection, and other studies have described the relevance of prophylactic vaccines in the management of genital warts. This review summarizes the leading features of therapeutic vaccines, which mainly target the early oncoproteins E6 and E7, and prophylactic vaccines, which are based on the L1 capsid protein. Through an analysis of the specific immunogenic properties of these two types of vaccines, we discuss why and how prophylactic vaccines can be effective in the treatment of HPV-related lesions and relapse. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) is an emerging public health issue in industrialized countries. In the last decade the number of autochthonous human infections has increased in Europe. Genotype 3 (HEV-3) is typically zoonotic, being foodborne the main route of transmission to humans, and is the most frequently detected in Europe in both humans and animals (mainly pigs and wild boars). In Italy, the first autochthonous human case was reported in 1999; since then, HEV-3 has been widely detected in both humans and animals. Despite the zoonotic characteristic of HEV-3 is well established, the correlation between animal and human strains has been poorly investigated in Italy. In the present study, we compared the subtype distribution of HEV-3 in humans and animals (swine and wild boar) in the period 2000–2018 from Italy. The dataset for this analysis included a total of 96 Italian ORF2 sequences (300 nt long), including both NCBI database-derived (n = 64) and recent sequences (2016–2018, n = 32) obtained in this study. The results show that subtype 3f is the most frequent in humans and pigs, followed by the HEV-3e, HEV-3c and other unassignable HEV-3 strains. Diversely, in wild boar a wider group of HEV-3 subtypes have been detected, including HEV-3a, which has also been detected for the first time in a human patient in Central Italy in 2017, and a wide group of unassignable HEV-3 strains. The phylogenetic analysis including, besides Italian strains, also sequences from other countries retrieved from the NCBI database, indicated that human Italian sequences, in particular those of HEV-3f and HEV-3e, form significant clusters mainly with sequences of animal origin from the same country. Nevertheless, for HEV-3c, rarely detected in Italian pigs, human sequences from Italy are more correlated to human sequences from other European countries. Furthermore, clusters of near-identical human strains identified in a short time interval in Lazio Region (Central Italy) can be recognized in the phylogenetic tree, suggesting that multiple infections originating from a common source have occurred, and confirming the importance of sequencing support to HEV surveillance. [ABSTRACT FROM AUTHOR]

New methods of HIV-1 RNA quantification based on dual-target detection are increasingly used in HIV viral load monitoring, but clinical implications and impact of dual-target detection on HIV-1 infection management are not established. Aptima HIV-1 Quant Dx assay is a last generation HIV viral load method, that uses pol and LTR as simultaneous target, providing quantitative results based mainly on pol target, while LTR target is used to report the results when pol signal is absent. In our laboratory, about 6% of results of all HIV-1 viral load tests performed with this platform in one year period resulted from LTR signal. Interestingly, LTR-based viremia (sometimes exceeding 1,000 copies/mL) was observed in a small proportion (up to 1%) of patients under ART, considered for long time virologically suppressed on the basis of a single target (pol-based) assay. Male gender, >700 vs <200 CD4 cell/mL and dual therapy including NRTI plus either NNRTI, or PI/b or INSTI were independently associated with increased risk of LTR-based HIV-1 viral load detection by multivariable logistic regression. A significant linear correlation was observed between LTR-based HIV-1 RNA levels and PBMC-associated proviral DNA. Moreover, in a small group of patients with HIV-1 RNA levels >200 copies/mL, longitudinal assessments showed parallel kinetics between plasma viremia and proviral DNA. Sequencing of pol region for drug resistance assessment in patients with LTR-based viremia failed on plasma HIV-1 RNA, while it was successful on proviral DNA. The detection/quantification of HIV-1 viremia based only on LTR signal with a dual target assay in samples resulting undetectable with the more conventional target pol needs accurate evaluation; unravelling the biological basis of this phenomenon, here described for the first time, is mandatory to establish relevance and implication by both pathogenetic (i.e. infectivity of LTR-detected viruses, reservoir turnover, immune activation, etc.) and clinical standpoint. [ABSTRACT FROM AUTHOR]

The possible existence of yet undiscovered human tumorigenic viruses is still under scrutiny. The development of large-scale sequencing technologies, coupled with bioinformatics techniques for the characterization of metagenomic sequences, have provided an invaluable tool for the detection of unknown, infectious, tumorigenic agents, as demonstrated by several recent studies. However, discoveries of novel viruses possibly associated with tumorigenesis are scarce at best. Here, we apply a rigorous bioinformatics workflow to investigate in depth tumor metagenomes from a small but carefully selected cohort of immunosuppressed patients. While a variegated bacterial microbiome was associated with each tumor, no evidence of the presence of putative oncoviruses was found. These results are consistent with the major findings of several recent papers and suggest that new human tumorigenic viruses are not common even in immunosuppressed populations. [ABSTRACT FROM AUTHOR]

Purpose: The frequency of detection of HBV co-infection with multiple HBV genotypes is influenced by the detection method; usually co-infections are detected by multiplex PCR or hybridization assays, and are rarely confirmed by sequencing and conventional cloning. The objective of this study was to confirm by ultra-deep pyrosequencing (UDPS) mixed HBV infections, previously detected by multiplex-nested PCR. Methods: Sixteen samples from HBV co-infected Sudanese patients detected by multiplex-nested PCR, were amplified targeting the P/S region and sequenced by UDPS. Results: The only genotypes identified using UDPS were D and E, while A, B, C and F genotypes, previously detected by multiplex-nested PCR, were not detected. Specifically, 10 samples were shown to be mono-infected (D or E); in 3 out of 10 mono-infected D patients, a subtype combination was observed: D1 + D7 in 2 cases and D2 + D6 in 1 case. The remaining 6 subjects were D + E co-infected (harboring different mixtures of D subtypes). Conclusions: Overall, UDPS is more effective than multiplex-nested PCR for identifying multiple HBV genotypes and subtypes infections. [ABSTRACT FROM AUTHOR]