Influenza

Repurposing Anticancer Drugs Targeting the MAPK/ERK Signaling Pathway for the Treatment of Respiratory Virus Infections

Respiratory virus infections remain a significant challenge to human health and the social economy. The symptoms range from mild rhinitis and nasal congestion to severe lower respiratory tract dysfunction and even mortality. The efficacy of therapeutic drugs targeting respiratory viruses varies, depending upon infection time and the drug resistance engendered by a high frequency of viral genome mutations, necessitating the development of new strategies. The MAPK/ERK pathway that was well delineated in the 1980s represents a classical signaling cascade, essential for cell proliferation, survival, and differentiation. Since this pathway is constitutively activated in many cancers by oncogenes, several drugs inhibiting Raf/MEK/ERK have been developed and currently used in anticancer treatment. Two decades ago, it was reported that viruses such as HIV and influenza viruses could exploit the host cellular MAPK/ERK pathway for their replication. Thus, it would be feasible to repurpose this category of the pathway inhibitors for the treatment of respiratory viral infections. The advantage is that the host genes are not easy to mutate such that the drug resistance rarely occurs during short-period treatment of viruses. Therefore, in this review we will summarize the research progress on the role of the MAPK/ERK pathway in respiratory virus amplification and discuss the potential of the pathway inhibitors (MEK inhibitors) in the treatment of respiratory viral infections.

Primary Vocal Cord Aspergillosis Can Involve the Trachea and Bronchus in Previously Healthy Patients: A Case Report

Primary vocal cord aspergillosis is extremely rare in immunocompetent individuals, in whom lesions are mainly confined to the larynx, with the possibility of tracheal and bronchial infection largely ignored. In this article, we present a case of primary vocal cord aspergillosis involving the trachea and bronchus in a previously healthy 55-year-old woman. Our case highlights that vocal cord aspergillosis can involve the trachea and bronchus and that laryngoscopy alone may be insufficient to secure a comprehensive diagnosis in healthy patients presenting with hoarseness, pharyngalgia, and normal chest radiography. Furthermore, influenza B virus infection may be a risk factor for this rare disease.

Vitamin D and immune system

The active metabolite of vitamin D 1,25(OH)2D is well known for its role in regulating calcium-phosphate homeostasis of the human body. However, the immunomodulating activity of 1,25(OH)2D has been known for many years. There are numerous reports correlating low vitamin D levels in blood serum with the onset of autoimmune diseases and with the severe course of acute infections. In this chapter, we address the role of 1,25(OH)2D in these diseases, and we discuss the possible mechanisms of action of 1,25(OH)2D in immune cells.

Unveiling the role of host kinases at different steps of influenza A virus life cycle

Influenza viruses remain a major public health concern causing contagious respiratory illnesses that result in around 290,000-650,000 global deaths every year. Their ability to constantly evolve through antigenic shifts and drifts leads to the emergence of newer strains and resistance to existing drugs and vaccines. To combat this, there is a critical need for novel antiviral drugs through the introduction of host-targeted therapeutics. Influenza viruses encode only 14 gene products that get extensively modified through phosphorylation by a diverse array of host kinases. Reversible phosphorylation at serine, threonine, or tyrosine residues dynamically regulates the structure, function, and subcellular localization of viral proteins at different stages of their life cycle. In addition, kinases influence a plethora of signaling pathways that also regulate virus propagation by modulating the host cell environment thus establishing a critical virus-host relationship that is indispensable for executing successful infection. This dependence on host kinases opens up exciting possibilities for developing kinase inhibitors as next-generation anti-influenza therapy. To fully capitalize on this potential, extensive mapping of the influenza virus-host kinase interaction network is essential. The key focus of this review is to outline the molecular mechanisms by which host kinases regulate different steps of the influenza A virus life cycle, starting from attachment-entry to assembly-budding. By assessing the contributions of different host kinases and their specific phosphorylation events during the virus life cycle, we aim to develop a holistic overview of the virus-host kinase interaction network that may shed light on potential targets for novel antiviral interventions.

Hypoxia Induces Alterations in the Circadian Rhythm in Patients with Chronic Respiratory Diseases

The function of the circadian cycle is to determine the natural 24 h biological rhythm, which includes physiological, metabolic, and hormonal changes that occur daily in the body. This cycle is controlled by an internal biological clock that is present in the body's tissues and helps regulate various processes such as sleeping, eating, and others. Interestingly, animal models have provided enough evidence to assume that the alteration in the circadian system leads to the appearance of numerous diseases. Alterations in breathing patterns in lung diseases can modify oxygenation and the circadian cycles; however, the response mechanisms to hypoxia and their relationship with the clock genes are not fully understood. Hypoxia is a condition in which the lack of adequate oxygenation promotes adaptation mechanisms and is related to several genes that regulate the circadian cycles, the latter because hypoxia alters the production of melatonin and brain physiology. Additionally, the lack of oxygen alters the expression of clock genes, leading to an alteration in the regularity and precision of the circadian cycle. In this sense, hypoxia is a hallmark of a wide variety of lung diseases. In the present work, we intended to review the functional repercussions of hypoxia in the presence of asthma, chronic obstructive sleep apnea, lung cancer, idiopathic pulmonary fibrosis, obstructive sleep apnea, influenza, and COVID-19 and its repercussions on the circadian cycles.

Influenza virus cell entry and targeted antiviral development

Influenza virus infection is currently one of the most prevalent and transmissible diseases in the world causing local outbreaks every year. It has the potential to cause devastating global pandemics as well. The development of anti-influenza drugs possessing novel mechanisms of action is urgently needed to control the spread of influenza infections; thus, drugs that inhibit influenza virus entry into target cells are emerging as a hot research topic. In addition to discussing the biological significance of hemagglutinin in viral replication, this article provides recent updates on the natural products, small molecules, proteins, peptides, and neutralizing antibody-like proteins that have anti-influenza potency.

Genetic analysis of cuproptosis subtypes and immunological features in severe influenza

The mechanisms regulating cuproptosis in severe influenza are still unknown. We aimed to identify the molecular subtypes of cuproptosis and immunological characteristics associated with severe influenza in patients requiring invasive mechanical ventilation (IMV). The expression of cuproptosis modulatory factors and immunological characteristics of these patients were analyzed using the public datasets (GSE101702, GSE21802, and GSE111368) from the Gene Expression Omnibus (GEO). Seven cuproptotic-associated genes (ATP7B, ATP7A, FDX1, LIAS, DLD, MTF1, DBT) related to active immune responses were identified in patients suffering from severe and non-severe influenza and two cuproptosis-associated molecular subtypes were discovered in severe influenza patients. Singe-set gene set expression analysis (SsGSEA) indicated that compared with subtype 2, subtype 1 was characterized by reduced adaptive cellular immune responses and increased neutrophil activation. Gene set variation assessment revealed that cluster-specific differentially expressed genes (DEGs) in subtype 1 were involved in autophagy, apoptosis, oxidative phosphorylation, and T cell, immune, and inflammatory responses, amongst others. The random forest (RF) model revealed the most differentiating efficiency with relatively small residual and root mean square error and an increased area under the curve value (AUC = 0.857). Lastly, a five-gene-based RF model (CD247, GADD45A, KIF1B, LIN7A, HLA_DPA1) was established, which showed satisfactory efficiency in the test datasets GSE111368 (AUC = 0.819). Nomogram calibration and decision curve analysis demonstrated its accuracy for the prediction of severe influenza. This study suggests that cuproptosis might be associated with the immunopathology of severe influenza. Additionally, an efficient model for the prediction of cuproptosis subtypes was developed which will contribute to the prevention and treatment of severe influenza patients needing IMV.

Inhibition of H3N2 Influenza Virus Induced Apoptosis by Selenium Nanoparticles with Chitosan through ROS-Mediated Signaling Pathways

In recent years, nanotechnology has received more and more attention in the antiviral field. Among them, selenium nanoparticles (SeNPs) have received a lot of attention. Chitosan, as a substance with antiviral effect, is limited by water solubility, low bioavailability, and poor stability. In this study, the combination of SeNPs with chitosan (Se@CS) showed less toxic and good anti-H3N2 infection effect. CCK-8 and RT-PCR showed that Se@CS effectively prevented H3N2 infection of MDCK cells by inhibiting viral replication and preventing cell fragmentation and cell aggregation. In addition, Se@CS can inhibit the excessive production of ROS and the change of mitochondrial membrane potential. More importantly, Se@CS can inhibit the late apoptosis of cells caused by virus, which may be related to the inhibition of apoptotic proteins in the ROS/JNK apoptotic signaling pathway. Finally, Se@CS was also found to inhibit H3N2-induced inflammation and alleviate infection. These results prove that Se@CS is a promising inhibitor for controlling influenza H3N2 virus infection.

Low influenza vaccine uptake by healthcare workers caring for the elderly in South African old age homes and primary healthcare facilities

BACKGROUND

The elderly bear the highest burden of South Africa's estimated annual > 10 million influenza cases and > 11,000 influenza-related deaths. Unvaccinated healthcare workers (HCWs) are at high occupational risk of contracting influenza, and may transmit influenza to elderly patients in their care. Thus, the South African National Department of Health recommends that HCWs receive annual influenza vaccination. This study aimed to determine influenza vaccination coverage among HCWs; identify reasons for their vaccination status; and investigate if HCWs recommend vaccination to their elderly patients.

METHODS

A descriptive study was conducted in 18 community health centres and 44 private sector and non-governmental organisation managed old age homes across South Africa, using a self-administered structured questionnaire, which was distributed to 360 HCWs present on the day of data collection. Data were captured using Microsoft Excel® and imported to Epi Info™ 7 (Centers for Disease Control and Prevention, USA) for descriptive statistical analysis. Ethics approval (SMUREC/P/36/2018: PG) and permission to conduct the study at the facilities were obtained. All participants provided informed consent.

RESULTS

The response rate was 76.7% (276/360). Most participants were female (90.9% [251/276]), nursing professionals (81.2% [224/276]) with a mean age of 41.1 ± 11.7 years. Although 62.7% of participants indicated having ever received at least one dose of the influenza vaccine, influenza vaccine uptake for 2017 and 2018 was 24.36% (41/276) and 33.3% (92/276) respectively. The main reasons given for never being vaccinated against influenza were related to the unavailability of the vaccine (70.9%) and vaccine hesitancy (27.2%). Most participants (67.8% [187/276]) recommended vaccines to elderly patients in their care.

CONCLUSION

The main reasons behind low influenza vaccine uptake by HCWs in South Africa who care for the elderly were related to unavailability of the vaccine and vaccine hesitancy. Strategies to educate HCWs on the importance of influenza vaccination, while concurrently increasing sustained and easy access to the vaccine by HCWs are needed to preserve public health.

Antiviral Drugs in Influenza

Flu is a serious health, medical, and economic problem, but no therapy is yet available that has satisfactory results and reduces the occurrence of these problems. Nearly 20 years after the registration of the previous therapy, baloxavir marboxil, a drug with a new mechanism of action, recently appeared on the market. This is a promising step in the fight against the influenza virus. This article presents the possibilities of using all available antiviral drugs specific for influenza A and B. We compare all currently recommended anti-influenza medications, considering their mechanisms of action, administration, indications, target groups, effectiveness, and safety profiles. We demonstrate that baloxavir marboxil presents a similar safety and efficacy profile to those of drugs already used in the treatment of influenza. Further research on combination therapy is highly recommended and may have promising results.

Influenza Vaccination Strategies in Healthcare Workers: A Cohort Study (2018-2021) in an Italian University Hospital

Vaccinating healthcare workers (HCWs) is the most effective intervention for preventing nosocomial influenza infection. However, influenza vaccination coverage (VC%) among HCWs remains low. The aim of the study was to analyse the trend of VC% among healthcare workers in an Italian hospital through a three-year vaccination project covering three influenza seasons (2018-2019, 2019-2020, and 2020-2021). A gap analysis was performed at the case base (2018-2019), on-site vaccination was trialled in the 2019-2020 season, and an integrated vaccination offer (on-site vaccination and the classic offer at a vaccination clinic) was implemented for the 2020-2021 season. For each unit of vaccinated HCWs, the following variables were recorded: main demographic details, area of affiliation (medical/surgical/services), and professional category. Logistic regression analyses were performed to assess the relationship between outcome (undergoing vaccination in 2020-2021) and other variables related to the healthcare workers' characteristics. In the three seasons, VC% values of 13.2%. 27.7%, and 58.9% were recorded, respectively (p < 0.005). The highest VC% was recorded among physicians (94.93%), in the medical area (63.27%), and males (62.59%) and in general among the youngest HCWs. Comparison of the coverage values recorded in the three seasons showed that in the last season considered (2020-2021) about 80% of health workers preferred to be vaccinated in the workplace instead of using the standard vaccination delivery method (invitation to attend the vaccination clinic). Our study suggests that the integrated vaccination offer may lead to an increase in VC% among HCWs compared to the classical offer modalities.

Metal Nanoparticles: a Promising Treatment for Viral and Arboviral Infections

Globally, viral diseases continue to pose a significant threat to public health. Recent outbreaks, such as influenza, coronavirus, Ebola, and dengue, have emphasized the urgent need for new antiviral therapeutics. Considerable efforts have focused on developing metal nanoparticles for the treatment of several pathogenic viruses. As a result of these efforts, metal nanoparticles are demonstrating promising antiviral activity against pathogenic surrogates and clinical isolates. This review summarizes the application of metal nanoparticles for the treatment of viral infections. It provides information on synthesis methods, size-related properties, nano-bio-interaction, and immunological effects of metal nanoparticles. This article also addresses critical criteria and considerations for developing clinically translatable nanosized metal particles to treat viral diseases.

Microfluidic-based virus detection methods for respiratory diseases

With the recent SARS-CoV-2 outbreak, the importance of rapid and direct detection of respiratory disease viruses has been well recognized. The detection of these viruses with novel technologies is vital in timely prevention and treatment strategies for epidemics and pandemics. Respiratory viruses can be detected from saliva, swab samples, nasal fluid, and blood, and collected samples can be analyzed by various techniques. Conventional methods for virus detection are based on techniques relying on cell culture, antigen-antibody interactions, and nucleic acids. However, these methods require trained personnel as well as expensive equipment. Microfluidic technologies, on the other hand, are one of the most accurate and specific methods to directly detect respiratory tract viruses. During viral infections, the production of detectable amounts of relevant antibodies takes a few days to weeks, hampering the aim of prevention. Alternatively, nucleic acid-based methods can directly detect the virus-specific RNA or DNA region, even before the immune response. There are numerous methods to detect respiratory viruses, but direct detection techniques have higher specificity and sensitivity than other techniques. This review aims to summarize the methods and technologies developed for microfluidic-based direct detection of viruses that cause respiratory infection using different detection techniques. Microfluidics enables the use of minimal sample volumes and thereby leading to a time, cost, and labor effective operation. Microfluidic-based detection technologies provide affordable, portable, rapid, and sensitive analysis of intact virus or virus genetic material, which is very important in pandemic and epidemic events to control outbreaks with an effective diagnosis.

Factors Associated with a Positive Severe Acute Respiratory Syndrome Coronavirus 2 Testing in Suspected Cases Presenting with Pneumonia: A Retrospective Cohort Study in a Single Medical Center

BACKGROUND

Coronavirus disease 2019 (COVID-19) has become a global emerging infectious disease.

OBJECTIVES

To analyze the initial clinical characteristics of COVID-19 suspected and confirmed patients on admission in order to find out which kinds may be more likely to get positive nucleic acid testing results, and to explore the risk factors associated with all-cause death.

METHODS

Medical records from 309 highly suspected cases with pneumonia were collected from February 13, 2020, to March 14, 2020, in a COVID-19-designated hospital of Wuhan. The majority of the clinical data were collected on the first day of hospital admission.

RESULTS

Of 309 patients with median age 64 years (interquartile ranges [IQR], 53-72 years), 111 patients (35.9%) were confirmed by nucleic acid testing (median age 64 years, IQR: 56-71 years; 48 males). Of those 111 patients, 13 (11.7%) patients died. In multivariate analysis, factors associated with positive testing included fatigue (odds ratios [OR] = 3.14; 95% confidence interval [CI]: 1.88-5.24, p < 0.001), cough (OR = 0.55; 95% CI: 0.32-0.95, p = 0.032), no less than 1 comorbidity (OR = 1.77; 95% CI: 1.06-2.98, p = 0.030), and severe pneumonia (OR = 2.67; 95% CI: 1.20-5.97, p = 0.016). Furthermore, age, dyspnea, noneffective antibiotic treatment, white blood cell, lymphocyte, platelets, and organ dysfunction (e.g., higher lactate dehydrogenase) were significantly associated with all-cause in-hospital death in patients with COVID-19.

CONCLUSION

Patients with severe forms of this disease were more likely to get positive results. Age and organ dysfunction were associated with a greater risk of death.

Flu Vaccination Attitudes, Behaviours, and Knowledge among Health Workers

The aim of this work is to evaluate the attitudes, behaviours, and knowledge of health workers employed at an Italian University Hospital on the topic of vaccinations and in regard to flu vaccination. To this end, the study provided for the articulation of a computerised questionnaire on the digital platform EUSurvey which was administered online via e-mail to a sample of 457 health workers, in the period between November 2018 and March 2019. The data were subjected to descriptive and inferential statistical analysis. In particular, a logistic regression analysis was carried out in order to evaluate the relationship between the variables collected and the dichotomous outcome (vaccinated/unvaccinated subjects in the 2018–2019 season). The results, in line with what has been reported by the literature, highlighted that vaccine hesitancy is prevalent also among health workers. Furthermore, according to our study, only 30.6% of the health care workers had the flu vaccination. The survey points out the need to plan educational and informative interventions aimed at changing the attitudes, behaviours, and knowledge of health workers in the field of flu vaccination, for the purpose of protecting the health of healthcare personnel and their patients.