State-of-the-Art Virology Research in Norway.

Norway is situated in a remote and sparsely inhabited part of the world with about 5 [...].

Virology under the Microscope-a Call for Rational Discourse.

Viruses have brought humanity many challenges: respiratory infection, cancer, neurological impairment and immunosuppression to name a few. Virology research over the last 60+ years has responded to reduce this disease burden with vaccines and antivirals. Despite this long history, the COVID-19 pandemic has brought unprecedented attention to the field of virology. Some of this attention is focused on concern about the safe conduct of research with human pathogens. A small but vocal group of individuals has seized upon these concerns - conflating legitimate questions about safely conducting virus-related research with uncertainties over the origins of SARS-CoV-2. The result has fueled public confusion and, in many instances, ill-informed condemnation of virology. With this article, we seek to promote a return to rational discourse. We explain the use of gain-of-function approaches in science, discuss the possible origins of SARS-CoV-2 and outline current regulatory structures that provide oversight for virological research in the United States. By offering our expertise, we - a broad group of working virologists - seek to aid policy makers in navigating these controversial issues. Balanced, evidence-based discourse is essential to addressing public concern while maintaining and expanding much-needed research in virology.

Towards application of CRISPR-Cas12a in the design of modern viral DNA detection tools (Review).

Early detection of viral pathogens by DNA-sensors in clinical samples, contaminated foods, soil or water can dramatically improve clinical outcomes and reduce the socioeconomic impact of diseases such as COVID-19. Clustered regularly interspaced short palindromic repeat (CRISPR) and its associated protein Cas12a (previously known as CRISPR-Cpf1) technology is an innovative new-generation genomic engineering tool, also known as 'genetic scissors', that has demonstrated the accuracy and has recently been effectively applied as appropriate (E-CRISPR) DNA-sensor to detect the nucleic acid of interest. The CRISPR-Cas12a from Prevotella and Francisella 1 are guided by a short CRISPR RNA (gRNA). The unique simultaneous cis- and trans- DNA cleavage after target sequence recognition at the PAM site, sticky-end (5-7 bp) employment, and ssDNA/dsDNA hybrid cleavage strategies to manipulate the attractive nature of CRISPR-Cas12a are reviewed. DNA-sensors based on the CRISPR-Cas12a technology for rapid, robust, sensitive, inexpensive, and selective detection of virus DNA without additional sample purification, amplification, fluorescent-agent- and/or quencher-labeling are relevant and becoming increasingly important in industrial and medical applications. In addition, CRISPR-Cas12a system shows great potential in the field of E-CRISPR-based bioassay research technologies. Therefore, we are highlighting insights in this research direction.

Successful co-infection of two different baculovirus species in the same cell line reveals a potential strategy for large in vitro production.

Baculoviruses have been applied for biocontrol of agricultural pests, such as velvetbean caterpillar (Anticarsia gemmatalis) and fall armyworm (Spodoptera frugiperda). Cell culture is an interesting approach for large-scale production of these viruses. Co-infection of a host cell with two distinct viruses can contribute to reduce costs due to saving cell culture media, bioreactor space and the resulting co-occluded polyhedra may help to reduce final biopesticide costs. The baculovirus Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV) and Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) were chosen to test a model for in vitro co-infection in SF21 cells. Different proportions of SfMNPV/AgMNPV were evaluated along three in vitro passages by optical microscopy analysis of cells and real-time PCR (qPCR) of DNA obtained from budded viruses (BVs) and occlusion bodies (OBs). The kinetics of viral protein synthesis was carried out for analysis of the co-infection in first passage and bioassays with the resulting OBs were performed against A. gemmatalis and S. frugiperda larvae. The results demonstrated successful co-infection in these cells. The quantity of SfMNPV and AgMNPV in supernatants and sediments tends to be maintained stable during the three passages, although the amount of AgMNPV was higher than SfMPNV in most of the experiments. Analysis of the kinetics of radiolabed proteins showed that the cell protein synthesis was shut off and two distinct bands of about 30 kDa, regarded to be the polyhedrin of each virus, were strongly detected at 48 and 72 hp.i. Although the pathogenicity of the produced viruses was not completely satisfactory, the bioassays confirmed occurrence of co-infected larvae with disproportional amount of each virus.

Application of machine learning in bacteriophage research.

Phages are one of the key components in the structure, dynamics, and interactions of microbial communities in different bins. It has a clear impact on human health and the food industry. Bacteriophage characterization using in vitro approaches are time/cost consuming and laborious tasks. On the other hand, with the advent of new high-throughput sequencing technology, the development of a powerful computational framework to characterize the newly identified bacteriophages is inevitable for future research. Machine learning includes powerful techniques that enable the analysis of complex datasets for knowledge discovery and pattern recognition. In this study, we have conducted a comprehensive review of machine learning methods application using different types of features were applied in various aspects of bacteriophage research including, automated curation, identification, classification, host species recognition, virion protein identification, and life cycle prediction. Moreover, potential limitations and advantages of the developed frameworks were discussed.

Trends Over Time in Use of Nonrecommended Tests and Treatments Since Publication of the American Academy of Pediatrics Bronchiolitis Guideline.

Importance: Acute viral bronchiolitis is a common and costly pediatric condition for which clinical practice guidelines discourage use of diagnostic tests and therapies. Objective: To evaluate trends over time for use of nonrecommended services for bronchiolitis since publication of the American Academy of Pediatrics clinical practice guideline on bronchiolitis (originally published in October 2006 and updated in November 2014). Design, Setting, and Participants: This cohort study was conducted using interrupted time-series regression analysis adjusting for the hospital providing service, patient demographic characteristics, and payer, with 2014 guideline update publication as the event point. Included patients were children younger than 2 years old discharged from the emergency department (ED) or hospital inpatient setting with a primary diagnosis of bronchiolitis at US Children's Hospitals contributing data to the Pediatric Health Information Systems database. Data were analyzed from June through December 2020. Main Outcomes and Measures: Rates of nonrecommended tests (ie, chest radiography, viral testing, and complete blood cell count) and treatments (ie, bronchodilators, corticosteroids, antibiotics) were measured. Results: Among 602 375 encounters involving children with a primary diagnosis of bronchiolitis, 404 203 encounters (67.1%) were ED discharges and 198 172 encounters (32.9%) were inpatient discharges; 468 226 encounters (77.7%) involved children younger than 12 months, and 356 796 encounters (59.2%) involved boys. In the period after initial guideline publication (ie, November 2006 to November 2014), a negative use trajectory was found in all measures except viral testing in the ED group. Using the 2014 guideline update as the event point, several measures showed decreased use between study time periods. The greatest decrease was in bronchodilator use, which changed by -13.5 percentage points in the ED group (95% CI, -15.2 percentage points to -11.8 percentage points) and -11.3 percentage points in the inpatient group (95% CI, -13.1 percentage points to -9.4 percentage points). In the period after the 2014 guideline update (ie, December 2014 to December 2019), bronchodilators also showed the greatest change in usage trajectory, steepening more than 2-fold in both groups. In the ED group, the negative trajectory steepened from -0.11% monthly (95% CI, -0.13% to -0.09%) in the first guideline period to a new mean monthly slope of -0.26% (95% CI, -0.30% to -0.23%). In the inpatient group, the mean monthly slope steepened from -0.08% (95% CI, -0.10 to -0.05%) to -0.26% (95% CI, 0.30% to -0.22%). Length of stay decreased from 2.0 days (95% CI, 1.9 days to 2.1 days) to 1.7 days (95% CI, 1.7 days to 1.8 days). Hospital admission rate decreased from 18.0% (95% CI, 13.8% to 22.2%) to 17.8% (95% CI, 13.6 to 22.1%). Conclusions and Relevance: This cohort study with interrupted time-series analysis found that use of most nonrecommended bronchiolitis services decreased continuously after 2006. The rate of decline in bronchodilator use increased more than 2-fold after the 2014 guideline update. These findings support potential associations of practice guidelines with improved bronchiolitis care.

Binomial nomenclature for virus species: a long view.

On several occasions over the past century it has been proposed that Latinized (Linnaean) binomial names (LBs) should be used for the formal names of virus species, and the opinions expressed in the early debates are still valid. The use of LBs would be sensible for the current Taxonomy if confined to the names of the specific and generic taxa of viruses of which some basic biological properties are known (e.g. ecology, hosts and virions); there is no advantage in filling the literature with formal names for partly described viruses or virus-like gene sequences. The ICTV should support the time-honoured convention that LBs are only used with biological (phylogenetic) classifications. Recent changes have left the ICTV Taxonomy and its Code uncoordinated, and its aims and audience uncertain.

SARS-CoV-2: Virology, epidemiology, immunology and vaccine development.

This first International Alliance for Biological Standardization Covid-19 webinar brought together a broad range of international stakeholders, including academia, regulators, funders and industry, with a considerable delegation from low- and middle-income countries, to discuss the virology, epidemiology and immunology of, and the vaccine development for SARS-CoV-2.

[Advances in molecular biology research on human parvovirus B19].

Human parvovirus B19 (B19 virus) is one of the two parvoviruses that cause human diseases. As an important pathogen to humans, it causes infectious erythema in children, acute aplastic anemia, fetal edema and death. In this review, we focus on the recent advances in the molecular virology of B19V, such as viral genotypes, viral receptor, genomic features and viral replication, viral transcription and post-transcription regulation, viral nonstructural and structural protein features and functions, viral diagnosis and antiviral agents, to provide reference for further study of B19 pathogenesis mechanisms, treatment and diagnostic strategies.

Microfluidics in Single-Cell Virology: Technologies and Applications.

Microfluidics has proven to be a powerful tool for probing biology at the single-cell level. However, it is only in the past 5 years that single-cell microfluidics has been used in the field of virology. An array of strategies based on microwells, microvalves, and droplets is now available for tracking viral infection dynamics, identifying cell subpopulations with particular phenotypes, as well as high-throughput screening. The insights into the virus-host interactions gained at the single-cell level are unprecedented and usually inaccessible by population-based experiments. Therefore, single-cell microfluidics, which opens new avenues for mechanism elucidation and development of antiviral therapeutics, would be a valuable tool for the study of viral pathogenesis.

Forty years with coronaviruses.

I have been researching coronaviruses for more than forty years. This viewpoint summarizes some of the major findings in coronavirus research made before the SARS epidemic and how they inform current research on the newly emerged SARS-CoV-2.