Respiratory Syncytial Virus Infection Research Articles

Evaluating the Effectiveness of Nirsevimab in Reducing Pediatric RSV Hospitalizations in Spain.

Background/Objectives: Respiratory syncytial virus (RSV) is a major cause of hospitalization in infants. Nirsevimab has demonstrated to be a promising tool for preventing severe RSV disease. Although clinical trials have demonstrated the efficacy of Nirsevimab in preventing severe RSV disease, evidence regarding its performance in real-world clinical settings is still limited due to its recent introduction. This study aims to fill this knowledge gap by evaluating the impact of Nirsevimab in a cohort of infants and determining its effectiveness in reducing the burden of RSV disease. Methods: A retrospective study of RSV hospitalizations was conducted in children under six months of age, between 1 October and 31 March, across four seasons: pre-COVID (2018-2019), COVID (2019-2020), post-COVID pre-Nirsevimab (2022-2023), and Nirsevimab season (2023-2024). Results: Nirsevimab demonstrated significant efficacy in reducing RSV-related hospitalizations in infants under six months of age. During the 2023/2024 season, following the introduction of Nirsevimab, there was a substantial reduction in RSV-related lower respiratory tract infection (LRTI) hospitalizations. Among infants under 3 months of age, hospitalizations decreased by 79.3% (IRR: 0.21, 95% CI: 0.12-0.34). In infants aged 3 to 6 months, there was a 66.9% reduction (IRR: 0.33, 95% CI: 0.15-0.64). Additionally, Nirsevimab decreased the severity of RSV cases with LRTI who required the support of equipment for sanitary use, further reducing overall healthcare burden. Conclusions: These results underscore Nirsevimab's vital role in preventing severe RSV infections and hospitalizations, especially among the most vulnerable infants, positioning it as a critical advancement in pediatric respiratory care.

Expert consensus on the passive immunization prevention of infant respiratory syncytial virus infection in China

Respiratory syncytial virus (RSV) infection, which has the very heavy disease burdens, is the most common viral pathogen that seriously threatens the health of infants and young children. In order to better guide and standardize the clinical diagnosis, treatment, monitoring and immunization prevention and control of RSV infection in China, the Chinese Preventive Medicine Association jointly organized multidisciplinary experts to form a special working group, drawing on the implementation experience of foreign passive immunization prevention of RSV, integrating the existing evidence and the latest progress as a problem oriented, and putting forward the expert consensus on the passive immunization prevention of infant RSV infection in China in the future. The aim is to answer some professional questions about RSV infection and its immunoprophylaxis, especially passive immunoprophylaxis, in order to provide reference for the practice of immunoprophylaxis for professionals in medical institutions, disease prevention and control institutions and community health service centers at all levels.

Comparative study on the epidemiological characteristics and hazards of respiratory syncytial virus and influenza virus infections among elderly people

ObjectiveTo investigate the epidemiological characteristics and infections of respiratory syncytial virus (RSV) and influenza viruses in hospitalized elderly patients with respiratory tract infections in Suzhou City, China, and to compare the differences in clinical characteristics and economic burden associated with these two infections.MethodsIn this prospective study, pathogenetic testing and clinical data for hospitalized patients aged 60 years and older with respiratory tract infections were collected in five hospitals through stratified cluster sampling from December 2023 to May 2024. Comparative study on epidemic characteristics, clinical features and costs of cases who infected RSV alone and influenza alone were conducted.ResultsAmong 1,894 cases included, the RSV positivity rate was 5.91% during the 2023–2024 winter-spring season, while the influenza positivity rate was 9.61%. RSV-B was the predominant subtype of RSV, and influenza A (primarily H3N2) was the dominant strain among the influenza-positive cases. Compared with cases infected influenza virus alone, those infected RSV alone had lower occurrence frequency of fever (18.8% vs. 35.7%, P = 0.004), higher occurrence frequency of complications of lower respiratory tract infections (70.8% vs. 54.8%, P = 0.011), higher direct medical costs ($996.2 vs. $841.1, P = 0.017) and total costs ($1019.7 vs. $888.1, P = 0.036). RSV single infection is more common in female cases (P = 0.007) and diabetic cases (P = 0.007) than influenza virus single infection.ConclusionsDuring the winter and spring months, RSV is the second most common pathogen after influenza virus among older adults hospitalized for respiratory infections in Suzhou, China. Patients infected RSV are more likely to develop complications with lower respiratory tract infections and have higher medical costs than the influenza. RSV infection in the elderly should be emphasized, especially in female patients and diabetic patients.

An altered natural killer cell immunophenotype characterizes clinically severe pediatric RSV infection.

Respiratory syncytial virus (RSV) infects nearly all children by 2 years of age and is a leading cause of pediatric hospitalizations. A subset of children with RSV infection (RSV+ children) develop respiratory failure requiring intensive care, but immune mechanisms distinguishing severe pediatric RSV infection are not fully elucidated. Natural killer (NK) cells are key innate immune effectors of viral host defense. In this study of 47 critically ill RSV+ children, we coupled NK cell immunophenotype and cytotoxic function with clinical parameters to identify an NK cell immune signature of severe pediatric RSV disease. Airway NK cells were increased in intubated RSV+ children with severe hypoxemia and prolonged duration of mechanical ventilation and were correlated with clinical severity scores. Peripheral blood NK cells were decreased in RSV+ patients and had altered activating receptor expression, with increased expression of CD69 and decreased expression of NKG2D. Ex vivo, circulating NK cells from RSV+ patients exhibited functional impairment characterized by decreased cytotoxicity as well as aberrant immune synapse assembly and lytic granule trafficking. NK cell frequency and phenotype correlated with clinical measures that defined disease severity. These findings implicate a role for NK cells in mediating RSV immunopathology and suggest that an altered NK cell immunophenotype is associated with severe RSV disease in young children.

ONCOLYTIC ACTIVITY OF HUMAN RESPIRATORY SYNCYTIAL VIRUS.

Oncolytic viruses (OVs) are emerging as novel tools in cancer therapy. Oncolytic virotherapy offers an attractive therapeutic combination of tumor-specific killing and immune co-stimulation, therefore amplifying the host immune response against tumors. Moreover, OVs can be engineered for the expression of different immunostimulatory molecules to optimize and enhance the efficacy of oncolytic virotherapy. The effectiveness of OVs has been demonstrated in many preclinical studies for different types of cancers to achieve the aim of personalized cancer therapy. Human respiratory syncytial virus (RSV), an RNA virus of the Pneumoviridae family causes severe lower respiratory tract infections in infants and immunocompromised individuals. Interestingly, the oncolytic activity of RSV demonstrated in human prostate, hepatocellular, and dermal cancer cells is mostly mediated via apoptotic cell death associated with the impaired NF-κB activation or with the defect of the IFNα/β-induced STAT-1 activation. At the same time, the studies on cervical cancer revealed that RSV infection resulted in autophagy activation and apoptosis through the ROS-BAX and TNF- α-mediated pathways. The rational combinations of OVs, including RSV, with other approaches may benefit patients whose response to conventional therapies is limited. Here, we discuss the oncolytic activity of RSV and its potential use against different types of cancer.

Expert consensus on the passive immunization prevention of infant respiratory syncytial virus infection in China

Respiratory syncytial virus (RSV) infection, which has the very heavy disease burdens, is the most common viral pathogen that seriously threatens the health of infants and young children. In order to better guide and standardize the clinical diagnosis, treatment, monitoring and immunization prevention and control of RSV infection in China, the Chinese Preventive Medicine Association jointly organized multidisciplinary experts to form a special working group, drawing on the implementation experience of foreign passive immunization prevention of RSV, integrating the existing evidence and the latest progress as a problem oriented, and putting forward the expert consensus on the passive immunization prevention of infant RSV infection in China in the future. The aim is to answer some professional questions about RSV infection and its immunoprophylaxis, especially passive immunoprophylaxis, in order to provide reference for the practice of immunoprophylaxis for professionals in medical institutions, disease prevention and control institutions and community health service centers at all levels.

A retrospective evaluation of SwePEWS use in paediatric patients with COVID-19 and RSV infection.

As early detection of deterioration is a challenge in children, the Swedish Paediatric Early Warning Score (SwePEWS) is used to systematically assess paediatric patients' clinical state. Here, we aimed to evaluate the use and predictive ability of SwePEWS. Electronic health records of paediatric patients admitted due to respiratory syncytial virus infection or COVID-19 were reviewed retrospectively. Registered vital signs were compared to the assigned SwePEWS score and monitored vital sign values to identify discrepancies. Additionally, SwePEWS's ability to predict transfer to the paediatric intensive care unit (PICU) was assessed. Among 1374 SwePEWS assessments, one-third were either incomplete or contained errors. Incomplete SwePEWS assessments were more frequent during night-time. Single measurements of oxygen saturation presented lower values compared to average saturation from continuous monitoring. SwePEWS's ability to predict PICU transfer was low. There was a surprisingly high occurrence of underestimated SwePEWS scores. This study provides new insights into pitfalls when developing and implementing paediatric early warning scores for systematic re-evaluations in paediatric patients.

Respiratory syncytial virus: an overview of clinical manifestations and management in the Indian pediatric population.

Respiratory syncytial virus (RSV) plays a major part in causing lower respiratory tract infections in younger populations, especially in infants and pediatric patients, causing a higher rate of morbidity and mortality in the respective population, affecting 60% of the population globally. Typically, identifying the virus in the patient's respiratory secretions is important for laboratory validation of a clinically suspected RSV infection. Unfortunately, the only available preventive measure to lower the incidence for infants who are at high risk of RSV-induced hospitalization is palivizumab prophylaxis. Treatment strategies to manage RSV involve using an antiviral drug that is Ribavirin along with bronchodilators, nebulized adrenaline (epinephrine), and nebulized hypertonic saline. Providing patients with alternative treatment options like vitamin D-cathelicidin as well as probiotics and prebiotics can help reduce the intensity of the infection. This review article focuses on the epidemiology, clinical manifestation, prophylaxis, and available treatment options for RSV infections in infants, children, and young adults.

Immediate post-discharge care among US adults hospitalized with respiratory syncytial virus infection

BackgroundRespiratory Syncytial Virus (RSV) is an important pathogen causing acute respiratory illnesses in adults. RSV infection can lead to severe outcomes, including hospitalizations and even death. Despite the increased recognition of the burden in older adults, immediate post-discharge care needs among adults hospitalized with RSV are not well characterized and have not been compared to other serious medical conditions (such as influenza, acute myocardial infarction (MI), and stroke) for which there have been long-standing disease prevention efforts.ObjectivesThis study aims to describe the immediate post-discharge care needs among adults hospitalized with RSV in the United States and descriptively compare it to those hospitalized with influenza, acute MI, or stroke.DesignRetrospective observational cohort study.PatientsAdults aged ≥ 18 years, hospitalized with a primary diagnosis of RSV, influenza, acute MI, or stroke from January 01, 2016, to December 31, 2019, were identified from the Premier Healthcare Database using the International Classification of Diseases (ICD-10) codes.Main measuresImmediate post-discharge care was categorized into three different levels of care based on the discharge dispositions. Descriptive analyses were performed.Key resultsIn total, 3,629 RSV, 303,577 influenza, 388,682 acute MI, and 416,750 stroke hospitalizations were identified, the majority occurred among patients aged ≥ 65 years. Professional home care needs were the highest for RSV hospitalizations (19.1%), followed by influenza (17.7%), stroke (15.4%), and acute MI (9.8%). Additionally, institutional care needs immediately following discharge were similar for RSV, influenza, and acute MI hospitalizations (14.2%, 15.8%, and 14.1%, respectively).ConclusionsImmediate post-discharge care needs among adults hospitalized with RSV, especially in older adults, can be considerable and comparable to influenza and acute MI discharges. With recently approved RSV vaccines, efforts to increase vaccination in older adults are needed to prevent RSV and associated healthcare consequences.

Prophylaxis of respiratory syncytial virus infection: current status and prospects for vaccine development

INTRODUCTION. Respiratory syncytial virus (RSV) is one of the most widespread pathogens that typically cause acute upper and lower respiratory tract infections in children and adults. Monoclonal antibody products have long been used for passive immunoprophylaxis in premature infants with bronchopulmonary dysplasia. However, vaccines have recently been licensed for the prophylactic immunisation of older adults with various risk factors for severe RSV infection (primarily, chronic cardiovascular and respiratory diseases and diabetes mellitus).AIM. This study aimed to review the current status of the development of vaccines for active immunisation against RSV infection, including the epidemiological rationale for their development, clinical trial results for licensed vaccines, recommendations for vaccination, and promising pipeline vaccines for RSV prevention.DISCUSSION. Initially hindered by the unique immunopathogenesis of RSV infection and the genetic hypervariability of RSV for a long time, attempts to develop an RSV vaccine succeeded when international researchers managed to identify a conservative neutralising antibody target capable of inducing specific immunity against RSV. This target, the RSV capsid protein stabilised in its prefusion (pre-F) conformation, can mediate viral entry into the cell following a conformational change. Several subunit vaccines based on recombinant pre-F proteins have successfully passed clinical trials and have been approved for the immunisation of older adults. In addition, one of these vaccines has been recommended for use during pregnancy to prevent RSV infection in newborns and infants. Currently, programmes are being implemented to develop novel RSV vaccines based on messenger RNA (mRNA) and non-replicating attenuated influenza vectors. This article examines and summarises the efficacy and safety parameters of two RSV vaccines approved in multiple countries around the world. Both vaccines have satisfactory safety profiles and comparable prophylactic efficacy parameters.CONCLUSIONS. Prelicensure clinical trials of novel RSV vaccines, including those being developed in the Russian Federation, should include prophylactic efficacy assessments in target patient populations. For vaccines approved by leading international regulators, clinical trials required for approval in the Russian Federation will be limited to bridging studies confirming the immunogenicity and safety of the vaccines.

Aging enhances pro-atrogenic gene expression and skeletal muscle loss following respiratory syncytial virus infection.

Aging and many age-related health conditions are associated with skeletal muscle loss. Furthermore, older adults are more susceptible to severe respiratory infections, which can in turn lead to muscle wasting. The mechanisms by which respiratory viral infection can impact skeletal muscle in older adults are not well understood. We determined the effects of acute infection with respiratory syncytial virus (RSV) on the lung and skeletal muscle of aged mice. RSV infection caused more severe disease in aged mice with enhanced weight loss, reduced feeding, higher viral load, and greater airway inflammation. Aged but not young mice showed decreased leg muscle weight at the peak of illness and decreased size of leg muscle fibers. Aged mice increased muscle-specific expression of atrophy-promoting enzymes (Atrogin-1 and MuRF-1) and failed to increase the rate of muscle protein synthesis during RSV infection. In aged mice, the changes in Atrogin-1 and MuRF-1 gene expression in skeletal muscle correlated with IL-6 levels in the lungs. These findings indicate that RSV infection of aged mice provides a model for studying the diverse adverse systemic consequences of respiratory viral infections on health and wellbeing in older adults.

A-315 Cardiac Troponin Concentrations in Pediatric Patients Infected with Respiratory Syncytial Virus

Abstract Background Respiratory syncytial virus (RSV) is associated with considerable morbidity and mortality in pediatric patients. Cardiac troponin I (TnI) has been shown to increase in patients with acute respiratory illness, including COVID-19. The impact of RSV infection on circulating TnI has been formally demonstrated in the literature. The goal of this study was to assess the relationship between TnI and respiratory syncytial virus (RSV) in pediatric patients. Methods A prospective study was conducted at St. Louis Children’s Hospital from October 2023 to February 2024. Patients older than 6 months who presented to the ED and had a CBC ordered within 6 hours of testing positive for RSV on the Biofire® FilmArray® Respiratory Panel were enrolled. Patients with Rhinovirus, Enterovirus, Streptococcus pneumoniae, or Adenovirus infections were included as controls. Remnant EDTA specimens were tested on an Abbott ARCHITECT i2000 for high sensitivity TnI (hs-TnI) with a limit of detection of 1.4 ng/L and a limit of quantitation of 3.5 ng/L. 99% upper reference limits from the CALIPER database on the Abbott of <7 ng/L were used as a threshold for positive results. The electronic medical record (EPIC) was assessed for demographic information and outcomes including length of stay (LOS), intensive care unit (ICU) length of stay, requirement of supplemental oxygen, white blood cell count (WBC), and creatinine. Results A total of 103 patients had RSV and 35 had other respiratory infections (ORI). The average age for the RSV positive group was 2.3 and for the ORI group was 2.4. Males made up 61% of the RSV+ group and 51% of the ORIs. 93 patients in the RSV group were admitted. The median TnI for RSV patients was 1.4 (IQR, 1.2-2.9) and for ORIs was 1.4 (IQR, 1.4-6.8). TnI was measurable in 58% of those with RSV and 54% in ORIs. We next assessed the correlation between hospital LOS and TnI in RSV+ patients, with a Pearson r of 0.42 (95% CI= 0.23-0.58). There was no correlation between WBC and LOS (r=-0.04, 95% CI=-0.25-0.17). There was also no correlation between TnI and WBCs or creatinine. Of admitted patients, 44 (47%) in the RSV group were in the ICU compared to 18 (51.4%) in those with ORIs. RSV+ patients that required ICU treatment had comparable TnI (1.4, IQR, 0.9-3.5) to those that didn’t require ICU stay (1.4, IQR, 0.75-1.5). There was no correlation between ICU LOS and TnI in RSV+ patients (r=-0.08, 95% CI=-0.39-0.24). There was a significant difference in mean TnI concentrations in RSV+ patients that required supplemental oxygen (8.7, 95% CI: 0-19) versus those that did not (1.7, 95% CI: 1.1-2.4). Conclusions There was no difference in TnI in patients hospitalized for RSV relative to ORIs. While TnI concentration was associated with LOS, there were minimally other associations between TnI and outcomes in patients hospitalized with RSV. While TnI elevations are associated with acute respiratory infections in adults, the impact on pediatric patients is not as clear. Future investigation is needed to understand how severe respiratory infections impact pediatric cardiac function.

Respiratory syncytial virus: Understanding the patient journey and healthcare burden

Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis in infants in the United Kingdom (UK), contributing to a significant burden of disease for the healthcare system and healthcare professionals (HCPs). To understand how an infant with RSV can impact the various levels of the healthcare system, we explore the patients' and caregivers' experiences through the system using available literature, which was supplemented through interviews with two separate caregivers of infants with a previous diagnosis of RSV disease. In the UK, most infants (~60%) will have experienced an RSV infection by their first birthday. Of these, some will require multiple healthcare encounters, including hospitalisations and admission to paediatric intensive care units. The burden of RSV disease extends beyond the healthcare system, with a substantial impact on the caregivers of affected infants.

Impact of respiratory tract infections on spinal muscular atrophy with focus on respiratory syncytial virus infections: a single-centre cohort study.

Spinal muscular atrophy (SMA) is a degenerative neuromuscular disorder leading to muscle hypotonia, weakness, and respiratory and bulbar impairment. Infants with SMA have an increased risk of respiratory tract infections (RTI) including severe respiratory syncytial virus (RSV) infections. Therefore, guidelines for the treatment of SMA recommend RSV prophylaxis with palivizumab for patients aged below two years who have compromised motor functions ("non-sitters"). Since palivizumab is not approved for RSV prophylaxis in SMA patients in Switzerland, payers usually do not grant cost approvals for this indication. Therefore, this study aimed to investigate the frequency of severe RTI among SMA patients focusing on RSV infections requiring hospital treatment and to determine the long-term impact of RSV infections on the natural history of SMA. A single-centre cohort study at the tertiary paediatric Neuromuscular Centre Zurich, Switzerland, including data of SMA patients with a genetic-based therapy initiated below two years of age between May 2019 and December 2022. All hospitalisations were analysed with a focus on severe RTI and especially RSV infections, and their impact on nutritional and respiratory function. The costs of inpatient treatment of RSV infections were determined and compared with estimated expenses for RSV prophylaxis with palivizumab. 12 SMA patients (median age at treatment initiation: 3.5 months, range: 0-17 months) were followed for a cumulative period of 25.75 years (7 SMA type 1; 5 SMA type 2 including one presymptomatic individual). With an incidence rate of 2.34 per patient-year, the risk of severe RTI was especially high in SMA type 1 (versus 0.1 in SMA type 2, p = 0.044). A total of 37 hospitalisations (279 hospital days) was necessary for the treatment of RTI in general; 9 of them were attributed to RSV infections (in 5 SMA type 1 patients; 84 hospital days). Only 3/12 SMA patients had received seasonal RSV prophylaxis with palivizumab. No RSV infections requiring hospital treatment occurred in patients while receiving seasonal RSV prophylaxis. During RTI, nutritional support had to be commonly initiated and continued after discharge. In 3/7 SMA type 1 patients, non-invasive ventilation was started during acute treatment for RTI and continued to the end of follow-up. We observed a high risk of RTI, especially RSV infections, among young SMA patients. Failure to adhere to established care protocols, for example by omitting RSV prophylaxis, may be linked to a heightened risk of morbidity in these children.

Q & A: Coding for Immunization Against Respiratory Syncytial Virus

The season for increased risk of respiratory syncytial virus (RSV) infection in the United States begins in October and continues through March. This means many practices are beginning to immunize infants against RSV for the 2024–2025 season. This article reviews coding for administration of the monoclonal antibody product, nirsevimab (RSV-mAb; brand name Beyfortus). This article answers questions on correct coding for immunization against RSV infection, including the following: What is the diagnosis code for RSV-mAb administration?What codes are reported for the RSV-mAb product?What codes are reported for RSV-mAb administration?How is administration of the 200-mg dose reported?Are evaluation and management (E/M) services reported separately?What are other billing and coding considerations for RSV-mAb?

Prevention of respiratory syncytial virus from 1991 to 2024: a systematic review and bibliometrics analysis.

Respiratory syncytial virus (RSV) puts children and elderly individuals worldwide at risk for severe health issues and financial difficulties. Prevention is the main treatment for RSV infection, as there is currently no particular therapy. By using bibliometrics analysis, this study attempted to map the increasing tendency in the prevention of RSV infection from January 1991 to August 2024 and to examine the frontiers and hotspots of related research. We extracted pertinent articles through the Web of Science Core Collection (WoSCC) on August 26, 2024, covering the period between January 1991 and August 2024. Then, an online bibliometrix interface (https://bibliometrics.com), R software (version 4.3.2), CiteSpace V6.1R6 (64-bit) software, and the Online Analysis Platform of Literature Metrology were used to analyze the data. A total of 709 eligible data points pertaining to the prevention of RSV were included. The United States, England, and the Netherlands were the three major contributors to this field. The most productive journal was Vaccine. Centers for Disease Control and Prevention ranked first, with 22 publications in this field. The fusion (F) protein, nonstructural (NS) protein and glycoprotein (G) protein are the target proteins of RSV prevention drugs. In the past 30 years, the research on RSV prevention has entered a stage of rapid development, and many vaccines and monoclonal antibodies have entered the clinical research stage, and some have been marketed.

Genotypic and phenotypic characterisation of respiratory syncytial virus after nirsevimab breakthrough infections: a large, multicentre, observational, real-world study

Nirsevimab, a long-acting monoclonal antibody, has been approved for the prevention of respiratory syncytial virus (RSV) infection in infants. In France, more than 210 000 single doses were administered in infants younger than 1 year during the 2023-24 season. In this context, the selection and spread of escape variants might be a concern. Here, we aimed to characterise RSV associated with breakthrough infection. We did a multicentre, national, observational study in France during the 2023-24 RSV season in RSV-infected infants (aged <1 year) who either received or did not receive a dose of nirsevimab before their first RSV season. We excluded infants with insufficient information about nirsevimab treatment or without parental consent. We used respiratory samples collected in each laboratory for full-length RSV RNA sequencing to analyse changes in the nirsevimab binding site Ø. We tested clinical RSV isolates for neutralisation by nirsevimab. We analysed F candidate substitutions by fusion-inhibition assay. Of the 695 RSV infected infants, we analysed 545 (78%) full-length RSV genome sequences: 260 (48%) from nirsevimab-treated breakthrough infections (236 [91%] RSV-A and 24 [9%] RSV-B) and 285 (52%) from untreated RSV-infected infants (236 [83%] RSV-A and 49 [17%] RSV-B). Analysis of RSV-A did not reveal any substitution in site Ø known to be associated with resistance to nirsevimab. Two (8%) of 24 RSV-B breakthrough infections had resistance-associated substitutions: F:N208D (dominant resistance-associated substitution) and a newly described F:I64M plus F:K65R combination (minority resistance-associated substitution), both of which induced high levels of resistance in the fusion-inhibition assay. This study is, to the best of our knowledge, the largest genotypic and phenotypic surveillance study of nirsevimab breakthrough infections to date. Nirsevimab breakthrough variants remain very rare despite the drug's widespread use. The detection of resistance-associated substitutions in the RSV-B F protein highlights the importance of active molecular surveillance. ANRS Maladies Infectieuses Emergentes and the French Ministry of Health and Prevention.

Risk factors for poor outcome in adult patients with respiratory syncytial virus infection evaluated at the emergency department.

Respiratory syncytial virus-associated acute respiratory infection (RSV-ARI) constitutes an emerging cause of morbidity in the adult population. The present retrospective study was aimed at identifying factors predictive of poor outcome that may be assessed at the first evaluation in the Emergency Department (ED). We included 275 adult patients with laboratory-confirmed RSV-ARI that required hospital admission from the ED between January 2018 and December 2019. Poor outcome (composite of progression to high-flow oxygen therapy, non-invasive or invasive mechanical ventilation, or intensive care unit admission, and/or 30-day all-cause mortality) occurred in 31 patients (11.2%). Immunosuppression was present in 59 patients (21.5%). Although bacterial co-infection was rare, antibiotic therapy was commonly initiated. Ribavirin was administered in 10 patients. Cognitive impairment (odds ratio [OR]: 2.452; 95% confidence interval [CI]: 0.990-6.072), concurrent oral anticoagulation (OR: 3.099; 95 CI: 1.287-7.464) and a pulse oximetry oxygen saturation to fraction of inspired oxygen ratio (SpO2/FiO2) ratio <382 at ED admission (OR: 3.013; 95 CI: 1.306-6.950) were independent risk factors for poor outcome, whereas influenza vaccination in the current season was protective (OR: 0.324; 95% CI: 0.138-0.763). Various factors easily available at the ED are useful for early risk stratification in adult patients with RSV-ARI.

Impact of respiratory syncytial virus infection among patients with hematological cancer in the era of post-coronavirus pandemic.

400 Background: Two vaccine is recently approved for elderly patient with compromised immunity. Despite the recommendation by Center for Disease Control and Prevention (CDC), RSV vaccination is remains low among patient with hematological malignancy, when compare to influenza vaccination. Thus, we conducted an observational study to estimate the impact of RSV infection among patients with hematological malignancy. Methods: We conducted a population-based retrospective cohort utilized the TritNetx dataset, which consist of patients across 63 U.S. healthcare organization. This study included patient who had respiratory viral infection after a diagnosis of hematological malignancy during 6/1/2022 - 4/1/2022. Hematological malignancy was identified using ICD-10 codes. CPT code and ICD-10 code were used to identify diagnosis of respiratory viral infection after respiratory pathogen panel testing. Patient who was diagnosed with RSV, influenza or COVID-19 were paired based on the following variable, including demographics, body mass index, comorbidities, and anti-neoplastic therapy. Hazard ratio (HR) was estimated by Cox proportional hazard regression models and log-rank test. Risk ratio (RR) was calculated by logistic regression. Results: A total of 6,088 patients with hematological malignancy contracted RSV, influenza or COVID during the observation period. When compare to influenza, patients with RSV infection were associate with high healthcare utilization, including emergency visit (HR: 1.20, 95% CI:[1.00-1.41]), and hospitalization (HR: 1.29, 95% CI:[1.06-1.57]). RSV infection was also resulted in higher acuity including viral pneumonia (HR: 15.42, 95% CI:[9.26-25.68]), use of antibiotics (HR: 1.54, 95% CI:[1.28-1.86]), renal replacement therapy (HR: 2.09, 95% CI:[1.10-3.96]), and acute respiratory failure (HR: 1.54, 95% CI:[1.14-2.07]). When compare to COVID-19, RSV infection showed similar trend including more frequent emergency visit (HR: 1.30, 95% CI:[1.10-1.54]), and high risk of developing viral pneumonia (HR 23.48, 95% CI: [12.79-43.09]). Interestingly, the intubation rate, 28 days all-cause mortality and 90 days all-cause mortality were similar between the three cohort. Conclusions: RSV infection was associated with higher rate of pneumonia and healthcare utilization. RSV vaccination should be considered to prevent RSV-associated morbidity among patients with hematological malignancy.

Reduced antiviral gene expression and elevated CXCL8 expression in peripheral blood are associated with severe hypoxemia in RSV-infected children.

The pathology of respiratory syncytial virus (RSV) infection remains unclear. An unbalanced immune response to RSV infection can lead to immunopathology, causing airway damage and impaired exchange of oxygen and carbon dioxide between the air and the bloodstream. We aimed to evaluate the association of the expression of inflammatory and antiviral genes in peripheral blood with severe hypoxemia in children with RSV infection seen in the hospital emergency room. We conducted a cross-sectional study on 121 RSV-infected children seen in hospital emergency rooms between 2015 and 2023. Total RNA was extracted from whole blood samples, and gene expression (IL-6, TNFα, CXCL8, ISG15, IFIT1, RIGI, IFNβ, CCL5, and CXCL10) was quantified using quantitative RT-PCR. The outcome variable was having severe hypoxemia (SpO2 ≤ 90%). The association analysis was performed using a volcano plot, adjusted logistic regression, and orthogonal partial least squares discriminant analysis (OPLS-DA). We found that 26 of 121 children had severe hypoxemia (SpO2 ≤ 90%). CXCL8 was overexpressed [fold changes (FC) > 2; q-value < 0.05], and ISG15, IFIT1, RIGI, IFNβ, CCL5, and CXCL10 were underexpressed (FC <0.5; q-value <0.05) in children with severe hypoxemia. These associations were ratified using adjusted logistic regression. The OPLS-DA showed that the gene expressions of CXCL8, ISG15, IFIT1, RIGI, and CXCL10 had values of variable importance in projection (VIP) ≥1, being the most relevant features. In conclusion, an imbalance favoring inflammation over antiviral defense may contribute to the pathogenesis of severe hypoxemia in RSV-infected children. These findings provide valuable insights into the pathology of RSV infection.