Epidemiology and clinical features of respiratory syncytial virus (RSV) infection in hospitalized children during the COVID-19 pandemic in Gorgan, Iran.

Background and Aims: Respiratory syncytial virus (RSV) is a leading cause of acute respiratory infection in infants and young children. Given the altered circulation patterns of respiratory viruses during the coronavirus disease pandemic-2019 (COVID-19), the study aimed to evaluate epidemiology and clinical features of RSV infections in hospitalized children during the COVID-19 pandemic in Gorgan, northeastern Iran. Molecular epidemiology studies on respiratory viral infections are necessary to monitor circulating viruses, disease severity, and clinical symptoms, in addition to early warning of new outbreaks. Methods: Overall, 411 respiratory swab samples from hospitalized children from October 2021 to March 2022 were collected at Taleghani Children's Hospital, Gorgan, Iran. The incidence of RSV, as well as the circulating subgroups and genotypes, were investigated and confirmed using PCR methods. Additionally, all samples tested for severe acute respiratory syndrome-associated coronavirus 2 (SARS-CoV-2) and influenza, and demographic and clinical data were analyzed using SPSS software. Results: The share of RSV, SARS-CoV-2, and influenza among hospitalized children with acute lower respiratory infections (ALRI) were 27%, 16.5%, and 4.1%, respectively. The RSV subgroup A (genotype ON1) was dominant over subgroup B (genotype BA9), with more severe clinical symptoms. Compared with the prepandemic era there were high numbers of hospitalized SARS-CoV-2 positive children and low numbers of other respiratory viruses. Despite this, the prevalence of ALRI-related RSV-disease among hospitalized children in our specialized pediatric center was higher than COVID-19 disease in the same cohort. Conclusions: Studying the epidemiology of respiratory viruses and determining the circulating strains can contribute to effective infection control and treatment strategies.

Hematological and Biochemical Laboratory Parameters in COVID-19 Patients: A Retrospective Modeling Study of Severity and Mortality Predictors.

Background: It is well known that laboratory markers could help in identifying risk factors of severe illness and predicting outcomes of diseases. Here, we performed a retrospective modeling study of severity and mortality predictors of hematological and biochemical laboratory parameters in Iranian COVID-19 patients. Methods: Data were obtained retrospectively from medical records of 564 confirmed Iranian COVID-19 cases. According to the disease severity, the patients were categorized into two groups (severe or nonsevere), and based on the outcome of the disease, patients were divided into two groups (recovered or deceased). Demographic and laboratory data were compared between groups, and statistical analyses were performed to define predictors of disease severity and mortality in the patients. Results: The study identified a panel of hematological and biochemical markers associated with the severe outcome of COVID-19 and constructed different predictive models for severity and mortality. The disease severity and mortality rate were significantly higher in elderly inpatients, whereas gender was not a determining factor of the clinical outcome. Age-adjusted white blood cells (WBC), platelet cells (PLT), neutrophil-to-lymphocyte ratio (NLR), red blood cells (RBC), hemoglobin (HGB), hematocrit (HCT), erythrocyte sedimentation rate (ESR), mean corpuscular hemoglobin (MCHC), blood urea nitrogen (BUN), and creatinine (Cr) also showed high accuracy in predicting severe cases at the time of hospitalization, and logistic regression analysis suggested grouped hematological parameters (age, WBC, NLR, PLT, HGB, and international normalized ratio (INR)) and biochemical markers (age, BUN, and lactate dehydrogenase (LDH)) as the best models of combined laboratory predictors for severity and mortality. Conclusion: The findings suggest that a panel of several routine laboratory parameters recorded on admission could be helpful for clinicians to predict and evaluate the risk of disease severity and mortality in COVID-19 patients.

Anti-inflammatory effects of curcumin-loaded niosomes on respiratory syncytial virus infection in a mice model.

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infection in paediatrics. While antivirals are apparent candidates to treat RSV-induced diseases, they have not yet met expectations and have remained in infancy. There is growing evidence to suggest that modulating the exacerbated inflammation during RSV infection can improve disease outcome. Curcumin-loaded niosomes have anti-inflammatory effects against RSV-induced respiratory disease by reducing immune cells' infiltration and inflammatory cytokines' production. This study evaluated the effects of curcumin-loaded niosomes on RSV-induced immunopathology in a mice model. Curcumin-loaded niosomes were prepared using the thin-film hydration method and characterized in vitro. Female Balb/c mice were infected by RSV-A2 and treated daily with curcumin-loaded niosomes. The potential anti-inflammatory effects of curcumin-loaded niosomes were evaluated on day 5 after infection. Using curcumin-loaded niosomes decreased immune cell influx and the inflammatory mediators (MIP-1α, TNF-α and IFN-γ) production in the lung, resulting in alleviated lung pathology following RSV infection. These findings indicate that curcumin-loaded niosomes have anti-inflammatory potential and could be a promising candidate to alleviate RSV-associated immunopathology.

Functional variation (Q63R) in the cannabinoid CB2 receptor may affect the severity of COVID-19: a human study and molecular docking.

Evidence supports a role of host genetic diversity in the clinical course of coronavirus disease 2019 (COVID-19). Variation in the cannabinoid CB2 receptor gene (CNR2) could affect the regulatory action of endocannabinoids on the immune system, resulting in an increased risk of various inflammatory diseases. The present study investigated the relationship between the CNR2-Q63R variant and COVID-19 severity. A total of 200 Iranian COVID-19 patients were enrolled in the study and genotyped using a TaqMan assay. The co-dominant, dominant, recessive, over-dominant, and additive inheritance models were analyzed using SNPStats software. In silico molecular docking was also performed to simulate the effects of the Q63R variation on CB2 binding with a ligand and with the G-protein. A significant difference in the Q63R allele and genotype distribution was found between expired and discharged COVID-19 patients in co-dominant, recessive, and additive inheritance models. The molecular docking results showed that the predicted structure of mutant CB2 (63R type) could not bind to the G-protein in the correct position. The data indicated that the Q63R variation in the CNR2 gene may affect the severity of COVID-19. Identification of genes related to susceptibility and severity of COVID-19 may lead to specific targets for drug repurposing or development.

COVID-19: Why does disease severity vary among individuals?

The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is responsible for the current pandemic, coronavirus disease 2019 (COVID-19). While all people are susceptible to the SARS-CoV-2 infection, the nature and severity of the disease vary significantly among individuals and populations. Importantly, reported disease burdens and case fatality rates differ considerably from country to country. There are, however, still uncertainties about the severity of the disease among individuals or the reason behind a more severe disease in some cases. There is a strong possibility that the severity of this disease depends on a complicated interaction between the host, virus, and environment, which leads to different clinical outcomes. The objective of this article is to point out the essential influential factors related to the host, virus, and environment affecting the clinical outcome of COVID-19.

Neutrophils in respiratory syncytial virus infection: From harmful effects to therapeutic opportunities.

Respiratory syncytial virus (RSV) is an important infectious agent in infants and young children. In most cases, RSV infection only causes mild disease, but in some, it requires invasive ventilation. Although antiviral drugs are obvious candidates to treat viral illness, and some have shown antiviral effects in humans, antivirals such as GS-5806, ALX-0171 and ALS-8176 have not yet met their expectations. Since the inappropriate or dysregulated immune response against RSV leads to harmful immune pathology, a robust immune cascade is probably underway by the time patients reach the hospital. RSV infection is associated with a strong neutrophil influx into the airway. It not clear if these cells contribute to antiviral defence or to lung pathology. This article discusses the protective and harmful roles of neutrophils during RSV infection and provides an overview of mechanisms by which neutrophil function could be targeted to prevent tissue injury and preserve homeostasis.

Ten challenging questions about SARS-CoV-2 and COVID-19.

INTRODUCTION: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recently introduced as a global public health problem by the World Health Organization (WHO). The virus outbreak has been documented around the world. Updating data in different aspects of the virus could force us to revise our idea about the main questions concerning coronavirus disease-19 (COVID-19). AREAS COVERED: Although our knowledge about the SARS-CoV-2 and COVID-19 is largely based on the very limited data, the information is growing rapidly. The renewed answers to the specific research questions concerning updating data not only reveal gaps for future research but also re-categorized our information. Here, we attempt to briefly discuss 10 important questions about SARS-CoV-2 and COVID-19. EXPERT OPINION: Since our knowledge about different aspects of SARS-CoV-2 appears to be in its infancy and is rapidly changing, the provision of the right data is more difficult in this regard. However, we try to rely on results from more extensive research to answer the main questions about this new virus. Therefore, further studies, particularly in the context of the virus pathogenesis, diagnosis, treatment, and vaccine development, are warranted.

Respiratory syncytial virus infection: why does disease severity vary among individuals?

Introduction: Respiratory syncytial virus (RSV) is the most common cause of acute lower respiratory tract infections in infancy. While many infants are infected with RSV, the nature and severity of the disease vary among individuals. RSV causes bronchiolitis, pneumonia, and asthma exacerbation. However, most children infected with RSV have only mild upper airways disease and may be asymptomatic.Areas covered: Despite efforts to elucidate mechanisms for the various clinical responses to RSV infection, they remain largely unknown, suggesting that susceptibility and disease are influenced by multiple intrinsic and extrinsic factors. This article reviews the available literature on the field of RSV disease severity and discusses important factors associated to susceptibility and different disease outcome.Expert opinion: The severity of RSV-induced illness is a phenomenon that depends on a variety of graded mechanisms of interaction between the host, virus, and environment. This may lead to differences in the intensity of immune response in the lung and different courses of the disease. By characterizing, classifying, and grading the affecting factors in high-risk patients versus those who do not fall ill by RSV, we may find therapies or point to disease-limiting medications.

Cannabinoid CB2 Receptor Functional Variation (Q63R) Is Associated with Multiple Sclerosis in Iranian Subjects.

The cannabinoid system has been identified as a critical endogenous regulator of immune homeostasis through immunomodulatory actions. This system is one of the main regulatory systems of the central nervous system (CNS). Variations in the cannabinoid CB2 receptor gene (CNR2) could affect intracellular signaling and reduce system function, which has been associated with an unbalanced immune response and increased risk of a variety of autoimmune inflammatory disorders. The present study investigated the relationship between CNR2 rs35761398 (Q63R) functional variation and multiple sclerosis (MS). A total of 100 Iranian MS patients and 100 healthy controls were enrolled in the study and genotyped through TaqMan assay. The co-dominant, dominant, recessive, over-dominant, and additive inheritance models were analyzed using SNPStats software. A significant genetic association was observed between Q63R polymorphism and MS. The dominant model was accepted as the best inheritance model to fit the data (OR 2.70, 95% CI 1.47-4.97, p = 0.001). The data implied the involvement of the CNR2 gene in susceptibility to MS in Iranian patients.