Epidemic Virus Research Articles

DAS-ELISA-based detection and RT-PCR validation for precise and timely analysis of Citrus tristeza virus infection in Nepalese citrus species

Citrus viral infections pose a substantial threat to the global citrus industry, resulting in multitudinous economic losses annually. Timely and precise identification of citrus viruses offers a promising avenue for proactive insights preemptively before the instigation of extensive infections. The present study was devised to expedite the prompt identification of the presence of Citrus tristeza virus (CTV) within Nepalese citrus species utilizing a Double Antibody Sandwich-Enzyme-Linked Immunosorbent Assay (DAS-ELISA), followed by its validation using reverse transcription PCR (RT-PCR). Samplings extracted from plants harvested from 74 out of the 77 administrative districts within Nepal provide substantial evidence of extensive propagation of viral contagion among citrus cultivars across 64 districts (86.48%) of the nation. A comprehensive analysis of the samples obtained from diverse geographical localities revealed that 36 districts (48.64%) exhibit mild infestation, while 9 districts (12.16%) evince moderate infestation. Moreover, samples harvested from 19 districts (25.67%) were highly infected; intriguingly, specimens from 10 districts (13.51%) manifest an absence of viral intrusion. The results have been validated with RT-PCR assay. Given the profound significance of citrus as a pivotal repository of vitamin C and its essential role in conferring advantageous health attributes to humankind, alongside its substantial contribution to the economic paradigm, a meticulous examination is imperative to safeguard these plants against an array of viral infections. Collectively, the DAS-ELISA methodology along with RT-PCR approaches constitutes an exquisitely sensitive and meticulously specific modality, poised to accelerate the expeditious detection of citrus-associated viruses within burgeoning economies like Nepal. This advancement supports timely and precise detection and diagnosis of agriculturally virulent conditions, thereby forestalling the eruption of viral epidemics and concomitantly curbing their financial repercussions.

Host factors influencing variable symptoms of COVID-19.

Similar to many other viruses, SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) causes various symptoms in individuals who have been exposed to the virus. Individuals exposed to the virus can be asymptomatic, mild, severe, and critical for mortality. Most hypotheses explaining the uncertainty of symptoms are based on innate immunity, which is unclear in explaining some issues. For example, 1. uncertain symptoms of SARS-CoV-2 infection, 2. failure to induce immunity for prevention by vaccines in some individuals, and 3. repeated infections in some individuals. With the ambition of explaining this clearly, this article proposed another perspective to explain the cause of uncertain symptoms in SARS-CoV-2-positive individuals. This could be influenced by host factors with a variety of cellular molecules (viral receptors/co-receptors) and major histocompatibility complex (MHC) polymorphisms, which are crucial factors in explaining this question. Hopefully, this perspective could encourage further research and pave the way for developing new public health policies to deal with COVID-19 and emergent viral epidemics in the future.

Natural History of Influenza B Virus-Current Knowledge on Treatment, Resistance and Therapeutic Options.

Influenza B virus (IBV) significantly impacts the health and the economy of the global population. WHO global health estimates project 1 billion flu cases annually, with 3 to 5 million resulting in severe disease and 0.3 to 0.5 million influenza-related deaths worldwide. Influenza B virus epidemics result in significant economic losses due to healthcare expenses, reduced workforce productivity, and strain on healthcare systems. Influenza B virus epidemics, such as the 1987-1988 Yamagata lineage outbreak and the 2001-2002 Victoria lineage outbreak, had a significant global impact. IBV's fast mutation and replication rates facilitate rapid adaptation to the environment, enabling the evasion of existing immunity and the development of resistance to virus-targeting treatments. This leads to annual outbreaks and necessitates the development of new vaccination formulations. This review aims to elucidate IBV's evolutionary genomic organization and life cycle and provide an overview of anti-IBV drugs, resistance, treatment options, and prospects for IBV biology, emphasizing challenges in preventing and treating IBV infection.

Impact of removing the healthcare mask mandate on hospital-acquired COVID-19 rates

Mandatory mask-wearing policies were one of several measures employed to reduce hospital-acquired SARS-CoV-2 infection throughout the pandemic. Many nations have removed healthcare mask mandates, but there remains a risk of new SARS-CoV-2 variants or epidemics of other respiratory viruses. To demonstrate the impact of removing the healthcare mask mandate. SARS-CoV-2 infections were analysed in a large teaching hospital for 40 weeks in 2022 using a controlled interrupted time-series design. The intervention was the removal of a staff/visitor surgical mask-wearing policy for the most wards at week 26 (intervention group) with a subset of specific wards retaining the mask policy (control group). The hospital-acquired SARS-CoV-2 infection rate was adjusted by the underlying community infection rate. In the context of a surge in SARS-CoV-2 infection, removal of the mask mandate for staff/visitors was not associated with a statistically significant change in the rate of nosocomial SARS-CoV-2 infection in the intervention group (incidence rate ratio: 1.105; 95% confidence interval: 0.523-2.334; P= 0.79) and there was no post-intervention trend (1.013; 0.932-1.100; P= 0.76) to suggest a delayed effect. The control group also showed no immediate or delayed change in infection rate. No evidence was found that removal of a staff/visitor mask-wearing policy had a significant effect on the rate of hospital-acquired SARS-CoV-2 infection. This does not demonstrate that masks were ineffective through the pandemic, but provides some objective evidence to justify the removal of healthcare mask mandates once there was widespread immunity and reduced disease severity.

APIPred: An XGBoost-Based Method for Predicting Aptamer-Protein Interactions.

Aptamers are single-stranded DNA or RNA oligos that can bind to a variety of targets with high specificity and selectivity and thus are widely used in the field of biosensing and disease therapies. Aptamers are generated by SELEX, which is a time-consuming procedure. In this study, using in silico and computational tools, we attempt to predict whether an aptamer can interact with a specific protein target. We present multiple data representations of protein and aptamer pairs and multiple machine-learning-based models to predict aptamer-protein interactions with a fair degree of selectivity. One of our models showed 96.5% accuracy and 97% precision, which are significantly better than those of the previously reported models. Additionally, we used molecular docking and SPR binding assays for two aptamers and the predicted targets as examples to exhibit the robustness of the APIPred algorithm. This reported model can be used for the high throughput screening of aptamer-protein pairs for targeting cancer and rapidly evolving viral epidemics.

Why Face Masks Should not be Imposed on the Public Again: A Review Article

Viral epidemics of acute respiratory infections pose a global threat. Influenza outbreaks occur almost every year. Specifically, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing coronavirus disease 2019 (COVID-19), emerged in late 2019. This unprecedented event resulted in many countries requiring masks in public spaces to contain the spread of SARS-CoV-2. However, the early and previous systematic reviews of randomized controlled trials (RCTs) found that medical/surgical masks did not appear to reduce respiratory viral infections. Also, N95 respirators did not provide superior protection over surgical masks against viral infections or influenza-like infections among healthcare workers (HCWs), although N95 respirators theoretically provide better protection. This led to the recommendation not to wear facemasks as potential benefits are limited, and there is a risk of self-contamination if misused. However, with the ongoing spread of SARS-CoV-2, several health authorities suddenly shifted their recommendations and advised the general public to wear masks, with some governments even mandating it. By July 2023, the health-protective benefits of wearing facemasks are still conflicting, and debate over the idea of a mask mandate is ongoing. Therefore, this review aims to discuss ten reasons why face masks should not be imposed on the public again, which include the functional weaknesses of facemasks, lack of justification for the sudden change in the recommendations during the COVID-19 pandemic, the effectiveness of facemasks in the community and among HCWs based on the systematic reviews of the RCTs, their effectiveness based on the RCTs, the effectiveness of N95 respirators versus surgical masks in protecting from acute respiratory infection based on the systematic reviews, their potential harms, the poor quality of most masks used by the public, their misuse, the trajectory of the COVID-19 pandemic despite masking, and the importance of acknowledgment of the rights of people in wearing masks or not.

Baseline and early changes in laboratory parameters predict disease severity and fatal outcomes in COVID-19 patients.

Coronavirus disease 2019 (COVID-19) has become the worst catastrophe of the twenty-first century and has led to the death of more than 6.9 million individuals across the globe. Despite the growing knowledge of the clinicopathological features of COVID-19, the correlation between baseline and early changes in the laboratory parameters and the clinical outcomes of patients is not entirely understood. Here, we conducted a time series cross-sectional study aimed at assessing different measured parameters and socio-demographic factors that are associated with disease severity and the outcome of the disease in 268 PCR-confirmed COVID-19 Patients. We found COVID-19 patients who died had a median age of 61 years (IQR, 50 y - 70 y), which is significantly higher (p < 0.05) compared to those who survived and had a median age of 54 years (IQR, 42y - 65y). The median RBC count of COVID-19 survivors was 4.9 × 106/μL (IQR 4.3 × 106/μL - 5.2 × 106/μL) which is higher (p < 0.05) compared to those who died 4.4 × 106/μL (3.82 × 106/μL - 5.02 × 106/μL). Similarly, COVID-19 survivors had significantly (p < 0.05) higher lymphocyte and monocyte percentages compared to those who died. One important result we found was that COVID-19 patients who presented with severe/critical cases at the time of first admission but managed to survive had a lower percentage of neutrophil, neutrophil to lymphocyte ratio, higher lymphocyte and monocyte percentages, and RBC count compared to those who died. To conclude here, we showed that simple laboratory parameters can be used to predict severity and outcome in COVID-19 patients. As these parameters are simple, inexpensive, and radially available in most resource-limited countries, they can be extrapolated to future viral epidemics or pandemics to allocate resources to particular patients.

The Oxford Nanopore MinION as a Versatile Technology for the Diagnosis and Characterization of Emerging Plant Viruses.

The emergence of novel viral epidemics that could affect major crops represents a serious threat to global food security. The early and accurate identification of the causative viral agent is the most important step for a rapid and effective response to disease outbreaks. Over the last years, the Oxford Nanopore Technologies (ONT) MinION sequencer has been proposed as an effective diagnostic tool for the early detection and identification of emerging viruses in plants, providing many advantages compared with different high-throughput sequencing (HTS) technologies. Here, we provide a step-by-step protocol that we optimized to obtain the virome of "Lamon bean" plants (Phaseolus vulgaris L.), an agricultural product with Protected Geographical Indication (PGI) in North-East of Italy, which is frequently subjected to multiple infections caused by different RNA viruses. The conversion of viral RNA in ds-cDNA enabled the use of Genomic DNA Ligation Sequencing Kit and Native Barcoding DNA Kit, which have been originally developed for DNA sequencing. This allowed the simultaneous diagnosis of both DNA- and RNA-based pathogens, providing a more versatile alternative to the use of direct RNA and/or direct cDNA sequencing kits.

Development and evaluation of a multiplex digital PCR method for sensitive and accurate detection of respiratory pathogens in children

The emergence of multiplex digital polymerase chain reaction (dPCR) and other detection technologies for respiratory pathogens in recent years has facilitated greater understanding of respiratory virus epidemics. In this study, a multiplex dPCR method was developed and evaluated as a means of detecting five respiratory pathogens in children with acute lower respiratory tract infection (ALRTI). With 139 nasopharyngeal swabs collected from children with ALRTI, pathogens were detected using dPCR and quantitative real-time PCR (qPCR) methods. Of those specimens, dPCR detected 86 positive cases, while qPCR identified 84. Moreover, dPCR exhibited higher sensitivity than qPCR, and displayed no cross-reactivity with common respiratory pathogens. These findings suggest that dPCR-based method could become one of the most promising options for acute respiratory pathogen detection.

Geodemographic profiles of COVID-19 mortality inside/outside nursing homes. Spatial analysis from microdata in North Spain

After two years of the COVID-19 pandemic, there is extensive research on the spread of the virus and geo-statistical analysis of spatial patterns. However, from the perspective of health geography, COVID-19 mortality is still under-studied. This research aims to provide a geographic profile of COVID-19 mortality, in terms of the space-time evolution and the relationship with individual and contextual variables. To this end, we geocoded the daily COVID-19 microdata of deceased persons provided by the Government of Cantabria (in northern Spain) from March 1, 2020 to March 31, 2022. The study also took cadastral variables, population records, and connections to geo-enrichment services accessed through ArcGIS Pro License (ESRI) into account. Using spatial statistics methods, such as 3D bins and emerging hot spots, local bivariate relationships, and ordinary least squares, we propose an exportable and scalable methodology to help policymakers cope with the current stage of living with the epidemic virus. Our results suggest that the spatial distribution of mortality is less clustered than that of contagion and shed light on differences in COVID-19 mortality profiles inside/outside nursing homes, such as higher age, and the temporal concentration of deaths in nursing homes. Spatial regimes showed hot spots of COVID-19 mortality in urban and metropolitan areas, with a pattern of repetition over time, such as sporadic hot spots that accounted for 36.28% of deaths in only 11.88% of the area with COVID-19 deaths. Despite immunization, periods of high contagion meant a subsequent increase in mortality, such as during the Omicron wave, where consecutive metropolitan hot spots accounted for 37.50% of the area and 51.45% of deaths were concentrated. Finally, there were interesting nuances in the significant local context variables of COVID-19 mortality compared with the explanatory factors of COVID-19 cases.

1711. Prospective Environmental Surveillance of Floors in a Pediatric Emergency Department During a Respiratory Syncytial Virus Surge in Ottawa, Canada

Abstract Background Annual respiratory syncytial virus (RSV) epidemics disproportionately impact infants and young children. Clinical surveillance is often restricted to laboratory-confirmed hospitalizations. Built environmental surveillance through floor sampling may provide population-level insights into RSV transmission dynamics and inform public health action to blunt community outbreaks.Figure:Quantification of viral detection from floor swabs in the pediatric emergency department by multiplex PCR Each point represents the number of viral copies, plus one, detected from a swab captured at a given location (y-axis) on a given date (x-axis). A value of one copy indicates non-detection of RSV. Methods A prospective environmental surveillance study was conducted in Ottawa, Canada from November 24, 2022 to March 24, 2023. Floors were swabbed in six areas of the emergency department (ED) of the sole pediatric acute care facility in Eastern Ontario. Samples were tested for RSV by a validated multiplex PCR assay. Floor swab positivity was compared to hospitalization data of patients with laboratory-confirmed RSV using Pearson’s correlation analysis to determine the degree of their association. Results Over an 18-week period, 432 floor swabs were collected in the ED and 250 pediatric patients were hospitalized. RSV was detected in 65% of floor swabs, with more viral copies detected in congregate areas (waiting rooms, triage) (Figure). The correlation between swab positivity and RSV hospitalizations was 0.64 (95%CI 0.23-0.86). Conclusion RSV was frequently detected on floors in the hospital-built environment and correlated somewhat with hospitalizations, likely reflecting community viral prevalence rather than severe RSV disease. Having real-time floor signals in different areas of the ED allowed for spatial resolution of the signal intensity, identifying higher RSV burden in areas where patients with infectious symptoms were more likely to congregate for prolonged periods of time. Floor sampling may be useful in developing spatially-refined approaches to infection prevention and control measures, particularly in indoor areas with increased respiratory viral transmission risks. Disclosures Evgueni Doukhanine, MSc, DNA Genotek: DNA Genotek provided sampling swabs in-kind for this study in an unrestricted fashion. Michael Fralick, MD, ProofDx: Advisor/Consultant

Assessing Stress and Anxiety in Firefighters During the Coronavirus Disease-2019 Pandemic: A Comparative Adaptation of the Stress and Anxiety in the Viral Epidemic-9 Items and Stress and Anxiety in the Viral Epidemics-6 Items Scales.

This study assessed the reliability and validity of the Stress and Anxiety to Viral Epidemics-9 items (SAVE-9) and Stress and Anxiety to Viral Epidemics-6 items (SAVE-6) scales for measuring viral anxiety among firefighters during the coronavirus disease-2019 pandemic. An online survey was conducted among 304 firefighters assigned in Gyeonggi-do. The SAVE-9 scale, initially developed for healthcare workers, was adapted for firefighters. We compared it with the SAVE-6 scale designed for the general population among the firefighters sample. The confirmatory factor analysis (CFA) was conducted to explore the factor structure of both scales. Internal consistency reliability was checked using Cronbach's alpha and McDonald's omega. Convergent validity was assessed in accordance with the Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7 scales. The SAVE-9 scale demonstrated a Cronbach alpha of 0.880, while the SAVE-6 scale yielded an alpha of 0.874. CFA indicated good model fits for both SAVE-9 and SAVE-6 scales among firefighters sample. The SAVE-9 and SAVE-6 comparably measures viral anxiety of firefighters. Both of the SAVE-9 and SAVE-6 scales are reliable and valid instruments for assessing viral anxiety among firefighters during the pandemic.

Effect of COVID-19 Risk Perception and COVID-19 Self-Care of Korean Correctional Nurses on Occupational Burnout: Mediating Effect of Stress and Anxiety About Viral Epidemics.

The purpose of this study was to investigate whether stress and anxiety about viral epidemics have effects as parameters in the relationship among COVID-19 risk perception, COVID-19 self-care, and occupational burnout for Korean correctional nurses. The subjects of this study were 107 correctional nurses working at 52 correctional facilities in Korea that are conducting COVID-19 management and prevention activities. Data were collected from March 12 to 30, 2022. Results suggest that correctional nurses during the COVID-19 pandemic may experience occupational burnout because of increased stress and anxiety about viral epidemics as their COVID-19 risk perception increased. In addition, stress and anxiety about being infected with the COVID-19 virus itself will cause burnout. This study contributes to promotion of the mental health of Korean correctional nurses and provides basic data for developing an intervention program to prevent occupational burnout.

Quantification of Plant Virus Seed Transmission Rate in Arabidopsis thaliana.

More than 25% of all known plant viruses are transmitted through seeds, which makes this mode of dispersal of great importance for plant virus epidemics. Virus detection in seed stocks remains the most frequent approach for seed health testing, but current methods are not always standardized and/or do not allow analyzing large numbers of seeds. Here, we describe a high-throughput method to quantify plant virus seed transmission rate based on classical grow-out tests, which can be applied to widely different viruses and host species.

Prevalence of respiratory viruses among hospitalized children with lower respiratory tract infections during the COVID-19 pandemic in Wuhan, China

ObjectivesWe aimed to investigate the continuous changes in respiratory virus epidemics in hospitalized children with lower respiratory tract infections (LRTIs) persisting from January 2019 to December 2022 in Wuhan, China. MethodsWe retrospectively enrolled children with LRTIs admitted to the Wuhan Children's Hospital. Specimens were nasopharyngeal aspirates which had been collected and detected the following microorganisms with direct immunofluorescence: influenza virus types A and B, respiratory syncytial virus, parainfluenza virus types 1-3, and adenovirus. We also analyzed demographic data and laboratory test results. ResultsA total of 22,660 patients were enrolled. The total virus detection rate in 2019, 2021, and 2022 significantly declined gradually (36.96% vs 29.47% vs 22.62%, P value < 0.001). All the detected viruses did not follow previously observed seasonal patterns during the COVID-19 pandemic. Children hospitalized for LRTIs were older during the COVID-19 pandemic in contrast to the pre-period, particularly notable in cases attributed to respiratory syncytial virus and parainfluenza virus type 3 infections. ConclusionsThis work adds to our knowledge of the epidemiology characteristics of respiratory viruses spanning the COVID-19 pandemic among children with LRTIs. The circulation of respiratory viruses changed consistently, and active LRTI surveillance in children remains critical for defining the healthcare burden of respiratory viruses.

Ultra-Sensitive Portable Visual Paper-Based Viral Molecularly Imprinted Sensor without Autofluorescence Interference.

Detection of the virus is the primary factor to discover and block the occurrence and development of the virus epidemic. Here, an ultrasensitive paper-based virus molecular imprinting sensor is developed to detect two viruses simultaneously in which the detection limit of the influenza virus (H5N1) is 16.0 aM (9.63 × 103 particles/mL) while that of the Hepatitis B Virus (HBV) is 129 fM (7.77 × 107 particles/mL). This paper-based sensor is low cost and is easy to cut, store, and carry. In addition, the visual semiquantitative detection of two viruses is achieved by using two aptamer-functionalized persistent luminescent nanoparticles as signal probes. These probes and the imprinted cavities on the paper-based material formed sandwich-type double recognition of the target viruses. This sensor has extremely high sensitivity to the H5N1 virus, which is of great value to solve the influenza epidemic with the most outbreaks in history, and also opens up a new way for the prevention and control of other virus epidemics. This cheap and portable visual sensor provides the possibility for self-service detection and can greatly reduce the pressure on medical staff and reduce the risk of virus infection caused by the concentration of people to be tested.

Plant-Derived Epi-Nutraceuticals as Potential Broad-Spectrum Anti-Viral Agents.

Although the COVID-19 pandemic appears to be diminishing, the emergence of SARS-CoV-2 variants represents a threat to humans due to their inherent transmissibility, immunological evasion, virulence, and invulnerability to existing therapies. The COVID-19 pandemic affected more than 500 million people and caused over 6 million deaths. Vaccines are essential, but in circumstances in which vaccination is not accessible or in individuals with compromised immune systems, drugs can provide additional protection. Targeting host signaling pathways is recommended due to their genomic stability and resistance barriers. Moreover, targeting host factors allows us to develop compounds that are effective against different viral variants as well as against newly emerging virus strains. In recent years, the globe has experienced climate change, which may contribute to the emergence and spread of infectious diseases through a variety of factors. Warmer temperatures and changing precipitation patterns can increase the geographic range of disease-carrying vectors, increasing the risk of diseases spreading to new areas. Climate change may also affect vector behavior, leading to a longer breeding season and more breeding sites for disease vectors. Climate change may also disrupt ecosystems, bringing humans closer to wildlife that transmits zoonotic diseases. All the above factors may accelerate the emergence of new viral epidemics. Plant-derived products, which have been used in traditional medicine for treating pathological conditions, offer structurally novel therapeutic compounds, including those with anti-viral activity. In addition, plant-derived bioactive substances might serve as the ideal basis for developing sustainable/efficient/cost-effective anti-viral alternatives. Interest in herbal antiviral products has increased. More than 50% of approved drugs originate from herbal sources. Plant-derived compounds offer diverse structures and bioactive molecules that are candidates for new drug development. Combining these therapies with conventional drugs could improve patient outcomes. Epigenetics modifications in the genome can affect gene expression without altering DNA sequences. Host cells can use epigenetic gene regulation as a mechanism to silence incoming viral DNA molecules, while viruses recruit cellular epitranscriptomic (covalent modifications of RNAs) modifiers to increase the translational efficiency and transcript stability of viral transcripts to enhance viral gene expression and replication. Moreover, viruses manipulate host cells' epigenetic machinery to ensure productive viral infections. Environmental factors, such as natural products, may influence epigenetic modifications. In this review, we explore the potential of plant-derived substances as epigenetic modifiers for broad-spectrum anti-viral activity, reviewing their modulation processes and anti-viral effects on DNA and RNA viruses, as well as addressing future research objectives in this rapidly emerging field.

Hypovirulence-associated mycovirus epidemics cause pathogenicity degeneration of Beauveria bassiana in the field

BackgroundThe entomogenous fungus Beauveria bassiana is used as a biological insecticide worldwide, wild B. bassiana strains with high pathogenicity in the field play an important role in controlling insect pests via not only screening of highly virulent strains but also natural infection, but the pathogenicity degeneration of wild strains severely affected aforementioned effects. Previous studies have showed that multiple factors contributed to this phenomenon. It has been extensively proved that the mycovirus infection caused hypovirulence of phytopathogenic fungi, which has been used for plant disease biocontrol. However, it remains unknown whether the mycovirus epidemics is a key factor causing hypovirulence of B. bassiana naturally in the field.MethodsWild strains of B. bassiana were collected from different geographic locations in Jilin Province, China, to clarify the epidemic and diversity of the mycoviruses. A mycovirus Beauveria bassiana chrysovirus 2 (BbCV2) we have previously identified was employed to clarify its impact on the pathogenicity of host fungi B. bassiana against the larvae of insect pest Ostrinia furnacalis. The serological analysis was conducted by preparing polyclonal antibody against a BbCV2 coat protein, to determine whether it can dissociate outside the host fungal cells and subsequently infect new hosts. Transcriptome analysis was used to reveal the interactions between viruses and hosts.ResultsWe surprisingly found that the mycovirus BbCV2 was prevalent in the field as a core virus in wild B. bassiana strains, without obvious genetic differentiation, this virus possessed efficient and stable horizontal and vertical transmission capabilities. The serological results showed that the virus could not only replicate within but also dissociate outside the host cells, and the purified virions could infect B. bassiana by co-incubation. The virus infection causes B. bassiana hypovirulence. Transcriptome analysis revealed decreased expression of genes related to insect epidermis penetration, hypha growth and toxin metabolism in B. bassiana caused by mycovirus infection.ConclusionBeauveria bassiana infected by hypovirulence-associated mycovirus can spread the virus to new host strains after infecting insects, and cause the virus epidemics in the field. The findings confirmed that mycovirus infection may be an important factor affecting the pathogenicity degradation of B. bassiana in the field.

From viral democratic genomes to viral wild bunch of quasispecies.

The tremendous majority of RNA genomes from pathogenic viruses analyzed and deposited in databases are consensus or "democratic" genomes. They represent the genomes most frequently found in the clinical samples of patients but do not account for the huge genetic diversity of coexisting genomes, which is better described as quasispecies. A viral quasispecies is defined as the dynamic distribution of nonidentical but closely related mutants, variants, recombinant,or reassortant viral genomes. Viral quasispecies have collective behavior and dynamics and are the subject of internal interactions that comprise interference, complementation, or cooperation. In the setting of SARS-CoV-2 infection, intrahost SARS-CoV-2 genetic diversity was recently notably reported for immunocompromised, chronically infected patients, for patients treated with monoclonal antibodies targeting the viral spike protein, and for different body compartments of a single patient. A question that deserves attention is whether such diversity is generated postinfection from a clonal genome in response to selection pressure or is already present at the time of infection as a quasispecies. In the present review, we summarize the data supporting that hosts are infected by a "wild bunch" of viruses rather than by multiple virions sharing the same genome. Each virion in the "wild bunch" may have different virulence and tissue tropisms. As the number of viruses replicated during host infections is huge, a viral quasispecies at any time of infection is wide and is also influenced by host-specific selection pressure after infection, which accounts for the difficulty in deciphering and predicting the appearance of more fit variants and the evolution of epidemics of novel RNA viruses.

Respiratory disorders and their association with clinical outcomes in COVID-19: a narrative review of current literature.

The coronavirus disease 2019, also known as COVID-19, has caused significant worldwide morbidity and mortality. Given the direct effect of severe acute respiratory syndrome virus-2 (SARS-CoV-2) on the respiratory system, it is important that clinicians who manage chronic respiratory conditions are familiar with the pathophysiology and impact of COVID-19 on pre-existing respiratory disease. Literature review relating to COVID-19 and respiratory disorders from PubMed and Google Scholar was conducted, with aim to encompass all publications relating to the most commonly encountered respiratory diseases in clinical practice, namely chronic obstructive lung disease (COPD), asthma, interstitial lung disease (ILD), obstructive sleep apnea (OSA), as well as obesity given it's known effect on both gas exchange and mechanistic aspects of respiration. The publications were analyzed for relevance to clinical implications and pathophysiologic mechanisms. Additional manual literature review was conducted based on citations from large review articles and society guidelines/statement papers. Certain respiratory disorders such as COPD, ILD, OSA, and obesity carry higher burden of morbidity and mortality associated with COVID-19. Surprisingly, and in contrast to previously studied viral epidemics, asthma does not carry increased associated risk of contracting the virus or worse clinical outcomes. A thorough understanding of the mechanisms responsible for control of breathing and the effect of COVID-19 on pulmonary pathophysiology will allow clinicians who manage chronic respiratory disease to effectively predict associated clinical outcomes as well as improve management strategies.