Respiratory Syncytial Virus Group Research Articles

Parent's perception of respiratory syncytial virus and subsequent wheezing burden: A multi-country cross-sectional survey.

Respiratory Syncytial Virus (RSV) is the leading cause of hospitalization in infants. RSV bronchiolitis is associated with an increased risk of subsequent wheezing. We aimed to document the parents' perception of the link between RSV infection and subsequent wheezing, wheezing-related healthcare and family resources use, and its impact on family daily life. This cross-sectional online survey enrolled 1200 parents with at least one child ≤6y living in the United States, United Kingdom, Spain, and Italy. Children diagnosed with RSV bronchiolitis before age of 2 years were included in the RSV group, and those never diagnosed with RSV bronchiolitis in the Reference group. The odds of wheezing were 4.5-fold (95%CI 3.5-5.9) higher in the RSV than in the Reference group. The odds increased to 7.7-fold (95%CI 5.4-11.1) among children who were hospitalized, and 9-fold (95%CI 5.1-16.6) among those admitted to pediatric intensive care with RSV bronchiolitis. Similar trends were observed across all countries. In total, 57% of parents reported their child's wheezing to have moderate to severe impact on their emotional well-being, and 53% on their daily life activities and/or social life. 64% of parents reported moderate-severe impact of wheezing on child's quality of sleep and 49% and 46% reported a moderate-severe impact on their children's emotional well-being and physical activities. This survey suggests an association between RSV infection and subsequent wheezing in children across different countries. Wheezing, especially in association with RSV infection, was associated with increased healthcare utilization and costs, and significantly impacted parents' and children daily life.

Genomic characterization of circulating human respiratory syncytial viruses A and B in Kuwait using whole-genome sequencing.

The human respiratory syncytial virus (RSV) is considered one of the most common viruses that infect children globally. The virus is known to have extensive gene sequence variability within and between RSV groups A and B globally; however, there is no information on the whole-genome characterization and diversity of RSV in Kuwait. Therefore, this study aimed to sequence the entire genome of RSV strains isolated from patients with acute respiratory tract infection (ARTI) in Kuwait. Therefore, this study aimed to sequence the entire genome of RSV strains isolated from patients with ARTI in Kuwait. Between January 2020 and September 2022, 7,093 respiratory samples were collected from hospitalized infants, children, and adults and were analyzed for respiratory viruses by multiplex real-time PCR. Whole-genome sequencing using the Oxford Nanopore sequencing technology was performed on 84 RSV-positive samples. The results revealed a higher prevalence of group A (76%) than group B (24%) RSV isolates. Phylogenetic analysis showed that RSV-A strains clustered with the GA2.3.5 sub-genotype and RSV-B strains clustered with the GB5.0.5a sub-genotype; however, forming new lineages of RSV-A and RSV-B circulated in Kuwait during this period. Genetic variability was higher among the group A viruses than group B viruses, and the rate of synonymous and missense mutations was high in genes other than the G protein-coding gene. We also detected several known and unique molecular markers in different protein-coding genes. This is the first study in Kuwait to characterize the whole genomes of RSV A and B to identify the circulating genotypes, comprehend the genetic diversity and the evolution of the virus, and identify important genetic markers associated with specific genotypes.IMPORTANCEWhole-genome sequencing of respiratory syncytial virus (RSV) strains in Kuwait using MinION Nanopore technology was used to characterize and analyze the genotypes and sub-genotypes of the RSV circulating among patients with acute respiratory tract infections in Kuwait. This study also identified known and unknown gene mutations and imported genetic markers associated with specific genotypes. These results will assist in establishing a framework for RSV classification and allow for a better consideration of the mechanisms leading to the generation of diversity of RSV. In addition, these data will allow a comparison of vaccine viruses with those in Kuwait, providing useful insights into future vaccine and therapy strategies for RSV in Kuwait.

Respiratory syncytial virus vs. Influenza virus infection: mortality and morbidity comparison over 7 epidemic seasons in an elderly population.

Respiratory syncytial virus (RSV) infection is gaining interest due to the recent development of vaccines, but it is still misdiagnosed in the elderly. The primary objective was to compare all-cause mortality at day 30. Secondary objectives were to compare clinical presentation, and rates of consolidative pneumonia, hospitalization, and intensive care unit (ICU) admission. Single-centre retrospective study conducted in a French university hospital during 7 epidemic seasons. All patients aged ≥75 years were included. 558 patients were included: 125 with RSV and 433 with Influenza. Median age was 84.8 years. RSV patients had more respiratory symptoms (wheezing, dyspnea), whereas Influenza patients had more general symptoms (fever, asthenia, myalgia). Consolidative pneumonia (28.8% vs. 17.2%; p = 0.004), hospitalization rates (83.2% vs. 70%; p = 0.003), ICU admissions (7.2% vs. 3.0%; p = 0.034) and length of stay (9 days [2-16] vs. 5 days [0-12]; p = 0.002), were higher in the RSV group. Mortality rates at day 30 were comparable (RSV 9.6%, Influenza 9.7%; p = 0.973). This study included the largest cohort of RSV-infected patients aged over 75, documented in-depth thus far. RSV shares a comparable mortality rate with Influenza but is associated with higher rates of consolidative pneumonia, hospitalization, ICU admissions, and extended hospital stays.

Severe Pneumonia Caused by Respiratory Syncytial Virus and Adenovirus in Children from 2 to 24 Months at Children's Hospital 1 in Ho Chi Minh City, Vietnam.

In Vietnam, due to the lack of facilities to detect respiratory viruses from patients' specimens, there are only a few studies on the detection of viral pathogens causing pneumonia in children, especially respiratory syncytial virus (RSV) and adenovirus (Adv). Here, we performed a cross-sectional descriptive prospective study on 138 children patients from 2 to 24 months old diagnosed with severe pneumonia hospitalized at the Respiratory Department of Children's Hospital 1 from November 2021 to August 2022. The number of patients selected in this study was based on the formula n = ([Z(1 - α/2)]2 × P [1 - P])/d2, with α = 0.05, p = 0.5, and d = 9%, and the sampling technique was convenient sampling until the sample size was met. A rapid test was used to detect RSV and Adv from the nasopharyngeal swabs and was conducted immediately after the patient's hospitalization. Laboratory tests were performed, medical history interviews were conducted, and nasotracheal aspirates were collected for multiplex real-time PCR (MPL-rPCR) to detect viral and bacterial pathogens. The results of the rapid test and the MPL-rPCR in the detection of both pathogens were the same at 31.9% (44/138) for RSV and 8.7% (7/138) for Adv, respectively. Using MPL-rPCR, the detection rate was 21% (29/138) for bacterial pathogens, 68.8% (95/138) for bacterial-viral co-infections, and 6.5% (9/138) for viral pathogens. The results showed few distinctive traits between RSV-associated and Adv-associated groups, and the Adv group children were more prone to bacterial infection than those in the RSV group. In addition, the Adv group experienced a longer duration of treatment and a higher frequency of re-hospitalizations compared to the RSV group. A total of 100% of Adv infections were co-infected with bacteria, while 81.82% of RSV co-infected with bacterial pathogens (p = 0.000009). This study might be one of the few conducted in Vietnam aimed at identifying viral pathogens causing severe pneumonia in children.

COMPARISON OF CLINICAL CHARACTERISTICS OF PATIENTS HOSPITALIZED DUE TO SARS-COV-2, INFLUENZA AND RESPIRATORY SYNCYTIAL VIRUS PNEUMONIA

OBJECTIVE: Influenza, respiratory syncytial virus (RSV), and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection are agents that spread through droplets, have similar symptoms and radiological findings, and can cause respiratory failure. This study was conducted to compare the clinical features and mortality rates of patients with novel coronavirus disease (COVID-19), influenza, and respiratory syncytial virus pneumonia. MATERIAL AND METHODS: A total of 182 patients who were hospitalized at Baskent University Medical Faculty Hospital due to COVID-19, influenza, and RSV were included in the study. Patients were grouped according to their clinical status. Demographic characteristics, comorbidities, laboratory and radiological findings, respiratory support treatments and mortality rates of the patients were recorded and compared between the groups. RESULTS: The mean age was 69.4±7 years in the COVID-19 group (n:115), 72.9±17.1 years in the influenza group (n:33), and 66.5±22.4 years in the RSV group (n:34). There was no difference in age between the groups (p=0.305). The hospitalization rate was higher for male patients in the COVID-19 group (p=0.036). There was no difference between the groups in terms of comorbidities (p>0.05). There was no difference in mortality rates between the COVID-19, RSV, and influenza patient groups (p=0.260). CONCLUSIONS: Viral infections with pulmonary involvement require special attention because they can have a poor clinical course. The severity of the clinical course of COVID-19 pneumonia, which causes deaths in the current century, is not different from the clinical course of viral infections such as influenza and RSV.

Clinical course and complications of RSV versus non-RSV bronchiolitis in hospitalised children

Introduction and objective: Bronchiolitis in young children often requires hospitalisation. It is mostly caused by respiratory syncytial virus (RSV) and aetiological factors may be associated with clinical presentation and prognosis. We aimed to compare the epidemiology, clinical features, severity and management of RSV and non-RSV bronchiolitis. Materials and methods: This cross-sectional retrospective study included hospitalised children under 2 years of age. Children with a positive rapid antigen diagnostic test and/or molecular study were included in the RSV group, while those with a negative result were classified as non-RSV bronchiolitis. We compared patient history, clinical presentation, disease severity including passive oxygen therapy, intensive care unit transfer, death, length of hospital stay, presence of complications, oxygen saturation <92%, acidosis, hypercapnia and treatment used. Results: The study included 524 patients (median age 2 months): 462 (88%) RSV and 62 (12%) non-RSV cases. A 7-fold increase in the number of cases was observed between 2010–2011 and 2017–2018. A univariate regression model showed lower odds of family history of atopy (odds ratio, OR = 0.46), higher odds of cough (OR = 4.74), apathy (OR = 2.61), feeding difficulties (OR = 2.03) and vomiting (OR = 3.34) in the RSV group. RSV patients required oxygen therapy (OR = 3.78) and antibiotics (OR = 2.82) more frequently, received inhaled steroid therapy for longer (9 vs. 8 days) and had a higher likelihood of complications (OR = 4.24). A multivariate model showed statistical significance for cough (OR = 6.22), oxygen therapy (OR = 4.43) and complications (OR = 15.95). Conclusions: We observed an increasing trend in bronchiolitis hospitalisations, including RSV bronchiolitis, which was associated with a more severe disease course. No significant clinical features were identified to replace laboratory tests.

Bronchial reactivity and asthma at school age after early-life metapneumovirus infection.

The association between early-life lower respiratory tract infection (LRTI) and asthma is well established. Knowledge about bronchial hyperresponsiveness (BHR) and asthma after metapneumovirus (MPV) LRTI is scarce. The aim of this study was to assess BHR and current asthma in school-aged children after hospital admission for early-life LRTI with MPV, and to compare with more well-known viruses, rhinovirus (RV) and respiratory syncytial virus (RSV), and with controls. A cohort consisting of children admitted for LRTI and controls was followed-up at school age with a clinical research assessment and lung function tests, including a methacholine provocation test. Current asthma was defined based on objective variable airway obstruction and clinical symptoms. BHR and asthma were compared according to viral groups. 135 children (median age 9.3 years) were included (16 MPV, 34 RV, 51 RSV, 13 mixed infections and 21 controls). Compared with controls there was increased BHR after MPV and RV LRTI (provocative dose causing a 20% fall in forced expiratory volume in 1 s and dose-response slope; p<0.05). Using Kaplan-Meier statistics, BHR was increased for MPV compared with both controls and RSV (p=0.02 and p=0.01). The proportion of children with current asthma at follow-up was higher in the LRTI children compared with the controls (46% versus 24%; p=0.06). Among children who had undergone MPV and RV infection, 50% fulfilled the asthma criteria compared with 43% in the RSV group (p=0.37). We found increased BHR and a high prevalence of asthma in school-aged children after early-life MPV infection, and findings were similar to RV, and less to RSV, compared with controls.

Characteristics and outcomes of patients hospitalized for infection with influenza, SARS-CoV-2 or respiratory syncytial virus in the season 2022/2023 in a large German primary care centre

BackgroundIn 2022/2023, Influenza A and Respiratory Syncytial Virus (RSV) reappeared in hospitalized patients, which was in parallel to ongoing SARS-CoV-2 infections. The aim of our study was to compare the characteristics and outcomes of these infections during the same time.MethodsWe included patients of all ages with a positive polymerase chain reaction (PCR) test for Influenza A/B, RSV, or SARS-CoV-2 virus hospitalized in the neurological, internal or paediatric units of the RoMed Hospital Rosenheim, Germany, between October 1st 2022 and February 28th 2023.ResultsA total of 906 patients were included (45.6% female; median age 68.0 years; 21.9% Influenza A, 48.2% SARS-CoV-2, 28.3% RSV). Influenza B (0.2%) and co-infections (1.5%) played a minor role. In patients aged ≥ 18 years (n = 637, 71%), Influenza A, SARS-CoV-2 and RSV groups differed in age (median 72, 79, 76 years, respectively; p < 0.001). Comorbidities, particularly asthma and COPD, were most prevalent for RSV. 103 patients were admitted to the intensive care unit (ICU) (16.3% Influenza A, 15.3% SARS-CoV-2, 19.2% RSV; p = 0.649), 56 died (6.8% Influenza A, 9% SARS-CoV-2, 11.1% RSV; p = 0.496). RSV showed the highest frequencies of low-flow oxygen supplementation for admission and stay. Differences in the length of stay were minor (median 7 days). Conversely, in patients aged < 18 years (n = 261, 28,8%), 19.5%, 17.6% and 60.2% were in the Influenza A, SARS-CoV-2 and RSV groups, respectively; 0.4% showed Influenza B and 2.3% co-infections. 17 patients were admitted to ICU (3.9% Influenza A, 9.6% RSV, 0% SARS-CoV-2); none died. RSV showed the highest frequencies of high- and low-flow oxygen supplementation, SARS-CoV-2 the lowest.ConclusionWhen comparing infections with Influenza, SARS-CoV-2 and RSV in the winter 2022/2023 in hospitalized adult patients, rates of ICU admission and mortality were similar. RSV showed the highest frequencies of obstructive airway diseases, and of oxygen supplementation. The latter was also true in children/adolescents, in whom RSV dominated. Thus, in the situation of declining importance of SARS-CoV-2, RSV showed a disease burden that was relatively higher than that from Influenza and SARS-CoV-2 across ages, and this might be relevant for the seasons coming.

Neutrophil-to-Lymphocyte Ratio and the Systemic Immune-Inflammation Index: Biomarkers in Infants with Bronchiolitis: a Cross-Sectional Study.

The use of a novel inflammatory indicator, the systemic immune-inflammatory index (SII), in pediatric patients with bronchiolitis remains unreported. Therefore, this study investigated the relationship between the SII and the neutrophil-to-lymphocyte ratio (NLR) in patients with respiratory syncytial virus (RSV) and non-RSV bronchiolitis and clinical severity prediction. This study analyzed the data of 155 patients aged <2 years who were hospitalized for viral bronchiolitis caused by RSV and/or other viral pathogens. The SII (platelet count × [neutrophil/lymphocyte]) was calculated and compared among patients with RSV mono-infections, other viral mono-infections, and RSV co-infections. Severity was defined by the number of days of supplemental oxygen treatment. The NLR and SII were significantly higher in the non-RSV mono-infection group than in the RSV mono-infection group, and the number of days of supplemental oxygen therapy was significantly higher in the RSV mono-infection group. No significant differences in the NLR, SII, or days of supplemental oxygen therapy were found between the RSV mono-infection and RSV co-infection groups. Although patients with RSV mono-infection showed more severe clinical findings than those without non-RSV mono-infection, the NLR and SII values were significantly higher in the non-RSV mono-infection group. Therefore, the NLR and SII do not appear to be very useful measurements for determining the severity of acute bronchiolitis attacks; however, lower NLR and SII values in the RSV group compared to the non-RSV group may be potential biomarkers for RSV infection. Therefore, further studies are warranted.

Severe Influenza Virus and Respiratory Syncytial Virus Infections in Intensive Care Over the Last 15 Years.

Influenza virus is a common agent of pediatric infections. Most cases are mild, but severe illness and death can occur. We aimed to analyze severe cases associated the influenza virus and compare it with respiratory syncytial virus(RSV). This is a retrospective study of 0-17-year-old patients admitted to the intensive care unit (ICU) of Hospital Pediátrico, Centro Hospitalar e Universitário de Coimbra (Pediatric Hospital, Coimbra Hospital and University Center), a tertiary pediatric hospital in Coimbra, Portugal, over the last 15 years (2008-2022) due to influenza virus infection. Clinical presentation, severity, and evolution were analyzed. A comparison of children with RSV infection admitted in the same period was performed. We identified 47 cases of influenza virus infection (34% coinfection with other viruses), median age of 2.3 years (interquartile range (IQR) 6.1), and 38% had comorbidities. The median admissions were three/year (maximum 11 in 2019). Influenza A was identified in 96%. Ninety-six percent had respiratory symptoms, 38% had neurologic symptoms, and 28% had sepsis. The main reason for admission was respiratory failure (68%). The mean pediatric index of mortality 2 (PIM2) at admission was 9±15.9%. Ventilatory support was necessary in 66%, vasoactive support in 19%, and blood products in 17%. The median length of stay was four days (IQR 5). There were four (8.5%) deaths. During the same study period, there were 171 RSV-related admissions. When comparing influenza (group A, without RSV coinfection) and RSV (group B), the first had a higher PIM2 on admission, greater need of ventilatory support, more complications, and higher mortality (p=0.001). The number of influenza virus infections admitted to ICU was much lower than RSV. However, influenza was more severe and associated with all deaths registered.

Analysis of the common respiratory viruses in children with acute respiratory infection in a hospital in Lanzhou City from 2021 to 2022

To explore the situation of 8 common respiratory pathogens in children with acute respiratory infection (ARI) from 2021 to 2022.The retrospective study selected 8 710 ARI patients from September 2021 to August 2022 in the Maternal and Child Health Hospital of Gansu Province as the study object, patients aged 0 to 17 years old, including 5 048 male children and 3 662 female children. Indirect immunofluorescence was used to detect 8 common respiratory pathogens, including influenza virus A (FluA), influenza virus B (FluB), parainfluenza virus (PIV), respiratory syncytial virus (RSV), adenovirus (ADV), Mycoplasma pneumoniae (MP), Chlamydia pneumoniae (CP), and Coxsackie virus group B (CoxB) IgM antibodies. χ2 test was used to analyze the results. The results showed that 1 497 of 8 710 children with ARI were positive, with a positive rate of 17.19%. The detection rate of MP among 8 common respiratory pathogens was 11.34%, accounting for 66.0%, followed by FluB, CoxB, PIV, RSV, ADV, FluA and CP, accounting for 13.83%, 9.55%, 6.01%, 2.61%, 1.47%, 0.40% and 0.13%, respectively. Respiratory tract viruses (FluA, FluB, RSV, ADV, PIV, CoxB) accounted for 33.86%.There were significant differences in the detection rates of PIV, ADV and MP among children of different genders (χ2=6.814, 5.154 and 17.784, P<0.05). The detection rate of school-age children (6-17 years old) was the highest, accounting for 33.27% (184/553). The detection rates of 8 common respiratory pathogens in patients with ARI were higher in spring and winter and lower in summer and autumn. To sum up, from 2021 to 2022, MP and FluB infection were dominant in ARI patients in our hospital. The peak period of 8 common respiratory pathogens was in spring and winter. The physical examination rate of 8 common respiratory pathogens in ARI patients aged 6-17 years old was the highest.

Epidemiology and Clinical Features of Human Metapneumovirus and Respiratory Syncytial Viral Infections in Children.

Human metapneumovirus (HMPV) and respiratory syncytial virus (RSV) are 2 common causes of acute respiratory tract infections in infants and young children. The objective of this study is to compare the demographics and outcomes of children hospitalized with HMPV and RSV infections in the United States. We performed a retrospective cohort analysis of children 1 month to less than 3 years old discharged during 2016 with HMPV or RSV infection using the Kids' Inpatient Database. Children with HMPV and RSV coinfection were excluded. Data were weighted for national estimates. There were 6585 children with HMPV infection and 70,824 with RSV infection discharged during the study period. The mean age of children with HMPV infection was higher than that of children with RSV infection (0.73 ± 0.8 vs. 0.42 ± 0.7 years; P < 0.05). The mortality rate was significantly higher in children with the presence of any complex chronic conditions compared to those without, in both HMPV [odds ratio (OR): 32.42; CI: 9.931-105.857; P < 0.05] as well as RSV (OR: 35.81; CI: 21.12-57.97; P < 0.05) groups. The adjusted median length of stay was longer (4.64 days; CI: 4.52-4.76 days vs. 3.33 days; CI: 3.31-3.35 days; P < 0.001) and total charges were higher ($44,358; CI: $42,145-$46,570 vs. $22,839; CI: $22,512-$23,166; P < 0.001), with HMPV infection. The mortality rate was similar in HMPV infection compared to RSV infection on multivariable analysis (OR: 1.48; P > 0.05). In hospitalized children in the United States, HMPV infection is less common than RSV infection. Complex chronic conditions are more prevalent in children hospitalized with HMPV infection. Hospitalization with HMPV is associated with longer length of stay and higher hospital charges. The adjusted mortality is similar with both infections.

Differences in the effects of Bordetella pertussis and respiratory syncytial virus infection on the composition of nasopharyngeal flora in neonates.

Bordetella pertussis and respiratory syncytial virus (RSV) are important pathogens causing cough in neonates. Few studies have investigated the differences in the effects of these two specific infections on respiratory flora. The aim of this study was to explore whether infections with Bordetella pertussis and RSV have different effects on respiratory floral composition in neonates. Nasopharyngeal respiratory flora was assessed by 16S ribosomal RNA amplification and V3-V4 region sequencing. Shannon and Simpson indices were calculated to determine the α diversity and principal coordinate analysis was performed to determine the β diversity. In total, 111 hospitalized neonates were divided into the pertussis (n = 29), RSV (n = 57), and control groups (n = 25) according to the pathogens detected. The relative abundance of Bordetella was significantly higher in the pertussis group (median: 19.18%, interquartile range: 72.57%). In contrast, this species was not detected in the other two groups. In the RSV group, the relative abundance of Streptococcus (median: 77.15%, interquartile range: 45.84%) was significantly higher than those in the pertussis and control groups (both P < 0.001). The α diversity of the RSV group was significantly lower than that of the control group (P < 0.001). Moreover, no statistically significant differences in the Shannon and Simpson indices were observed between the pertussis and control groups (P = 0.101 and P = 0.202, respectively). Principal coordinate analysis revealed a large overlap between the pertussis and control groups and a significant distance between the RSV and control groups without any overlap. Thus, the effects of infections with the two species, B. pertussis and RSV, impacted the diversity of nasopharyngeal flora differently. The principles underlying the difference in the effects of different pathogens on microbial flora require further investigation.

New Generation of Systemic Inflammatory Markers for Respiratory Syncytial Virus Infection in Children.

This study evaluated the relationship between the systemic immune-inflammatory index (SII), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) with clinical findings of respiratory syncytial virus (RSV) infection among children with a diagnosis of lower respiratory tract infection (LRTI). The study was conducted between 1 January 2020 and 1 January 2022 in a pediatric clinic. This retrospective study included 286 consecutive patients between 0 and 12 years of age, 138 of whom were RSV (+) (48.25%) and 148 of whom were RSV (-) (51.75%). The detection of the RSV antigen was carried out using the chromatographic immunoassay method on nasopharyngeal swabbing samples. CRP content was significantly higher in patients with RSV (+) than in children with RSV (-), while NLR, PLR, and SII, as inflammatory parameters, were significantly lower. Fever, coughs, and wheezing were the most common symptoms in the RSV (+) groups (100%). RSV infections were the highest in November, October, and December, in that order. The AUC was statistically significant for parameters in all groups. AUC values were 0.841 (95%: 0.765-0.917) for leukocytes, 0.703 (95%: 0.618-0.788) for lymphocytes, 0.869 (95%: 0.800-0.937) for CRP, 0.706 (95%: 0.636-0.776) for NLR, 0.779 (95%: 0.722-0.836) for PLR, and 0.705 (95%: 0.633-0.776) for SII. CRP was found to have both high sensitivity (80.4%) and high specificity (82.4%) among all parameters. While the ROC analysis results showed similar results for children under two years old, only CRP and NLR were statistically significant in this group. CRP performed better than other blood parameters as a marker. The NLR, PLR, and SII index were significantly lower in LRTI patients with RSV (+) than in those with RSV (-), which implies a higher grade of inflammation. If the cause of the disease can be determined by this method, disease management will be easier, and unnecessary antibiotics could be avoided.

Prevalence, variation, and transmission patterns of human respiratory syncytial virus from pediatric patients in Hubei, China during 2020–2021

Human respiratory syncytial virus (RSV) is a severe threat to children and a main cause of acute lower respiratory tract infections. Nevertheless, the intra-host evolution and inter-regional diffusion of RSV are little known. In this study, we performed a systematic surveillance in hospitalized children in Hubei during 2020–2021, in which 106 RSV-positive samples were detected both clinically and by metagenomic next generation sequencing (mNGS). RSV-A and RSV-B groups co-circulated during surveillance with RSV-B being predominant. About 46 high-quality genomes were used for further analyses. A total of 163 intra-host nucleotide variation (iSNV) sites distributed in 34 samples were detected, and glycoprotein (G) gene was the most enriched gene for iSNVs, with non-synonymous substitutions more than synonymous substitutions. Evolutionary dynamic analysis showed that the evolutionary rates of G and NS2 genes were higher, and the population size of RSV groups changed over time. We also found evidences of inter-regional diffusion from Europe and Oceania to Hubei for RSV-A and RSV-B, respectively. This study highlighted the intra-host and inter-host evolution of RSV, and provided some evidences for understanding the evolution of RSV.

RSV causes more severe respiratory illness than influenza in admitted children under 2‐years‐old

Both respiratory syncytial virus (RSV) and influenza-associated lower respiratory tract infections (LRTI) cause serious respiratory infections in infants and toddlers. We aimed to assess the frequency of complex hospital courses among patients admitted with influenza versus RSV LRTI. A retrospective cohort study was performed on admissions of children <2 years who were admitted for LRTI and tested positive for influenza or RSV from 2016 to 2019. The primary outcome, complex hospital course, was a composite including: intensive care unit admission, respiratory support, nasogastric tube feeds, prolonged length of stay, and death. Secondary outcomes included 7-day readmission and time to respiratory support. Differences between RSV and influenza groups were assessed and unadjusted and adjusted regression models and competing risks time to event models were developed. There were 1094 (89%) RSV admissions and 134 (11%) influenza admissions. Children admitted for influenza were significantly older (336 vs. 165 days, p < 0.001), more likely to present with an abnormal heart rate for age (84.3% vs. 73.5%, p < 0.01) and a fever (27.6% vs. 18.9%, p = 0.02). Admissions with RSV were significantly more likely to experience a complex hospital course (ORadj = 3.5, 95% CI: 2.2-5.6). In time to event analysis, RSV admissions had a significantly higher rate of respiratory support (HRadj = 3.2, 95% CI: 2.0, 5.2). Readmission rates were similar. RSV admissions were associated with a higher risk for a complex hospital course and required higher rates of respiratory support than influenza admissions. This information may help in evaluating hospital resources and admissions.

Epidemiology and Characteristics of Respiratory Syncytial Virus Pneumonia in Critically Ill Adults.

Severe respiratory syncytial virus (RSV)-associated pneumonia in adults has rarely been addressed. We investigated the burden and clinical characteristics of severe RSV-associated pneumonia in critically ill adult patients. We analyzed a prospective cohort of 2865 adults with severe pneumonia who were admitted to the intensive care unit in a 2700-bed tertiary care hospital from 2010 to 2019. The epidemiology, characteristics, and outcomes of 92 cases of severe RSV-associated pneumonia and 163 cases of severe influenza virus (IFV)-associated pneumonia were compared. Of 1589 cases of severe community-acquired pneumonia, the incidence of RSV-associated pneumonia was less than half that of IFV-associated pneumonia (3.4% vs 8.1%). However, among 1276 cases of severe hospital-acquired pneumonia (HAP), there were slightly more cases of RSV-associated than IFV-associated pneumonia (3.8% vs 3.5%). During the 9 epidemic seasons, RSV-A (5 seasons) and RSV-B (4 seasons) predominated alternately. Structural lung disease, diabetes mellitus, and malignancy were common underlying diseases in both groups. Immunocompromise (57.6% vs 34.4%; P < .001) and hospital acquisition (47.8% vs 23.9%; P < .001) were significantly more common in the RSV group. Coinfection with Streptococcus pneumoniae (3.3% vs 9.8%; P = .08) and methicillin-susceptible Staphylococcus aureus (1.1% vs 6.8%; P = .06) tended to be less frequent in the RSV group. The 90-day mortality was high in both groups (39.1% vs 40.5%; P = .89). RSV infection was associated with substantial morbidity and mortality in critically ill adult patients, similar to IFV. The relatively higher incidence of RSV in severe HAP suggests that the transmissibility of RSV can exceed that of IFV in a hospital setting.

Comparison of COVID-19 and RSV Infection Courses in Infants and Children under 36 Months Hospitalized in Paediatric Department in Fall and Winter Season 2021/2022

The study aimed to determine the differences between COVID-19 and Respiratory syncytial virus (RSV) infections in young children hospitalized in the pediatric department. This retrospective study included 52 children with COVID-19 and 43 children with RSV infection younger than 36 months hospitalized in a pediatric department between September 2021 and March 2022. Clinical and laboratory findings, methods of treatment and hospitalization length were compared. In the RSV group, significantly higher rates of cough (93.2% vs. 38.5%), rhinitis (83.7% vs. 50%), dyspnea (83.7% vs. 21.1%), crackles (69.8% vs. 5.8%) and wheezes (72.1% vs. 9.6%) were observed. The COVID-19 group had significantly higher rates of fever (80.8% vs. 37.2%) and seizures (13.5% vs. 0%). Patients with RSV infection had significantly higher rates of bronchodilator therapy (88.37% vs. 5.77%) and oxygen therapy (48.8% vs. 7.7%) and required a longer hospital stay (8 vs. 3 days). In admission, the majority of the patients from both groups were not treated with antibiotics, but because of clinical deterioration and suspected bacterial co-infections, antibiotics were administered significantly more frequently in the RSV group (30.2% vs. 9.6%). RSV infection in infants and small children had a more severe course than COVID-19 infection. RSV infection was associated with a longer hospitalization period and required more elaborate treatment.

Cytokine expression in rhinovirus- vs. respiratory syncytial virus-induced first wheezing episode and its relation to clinical course.

Rhinovirus (RV) and respiratory syncytial virus (RSV) are common causes of bronchiolitis. Unlike an RSV etiology, an RV etiology is associated with a markedly increased risk of asthma. We investigated the cytokine profiles of RV- and RSV-induced first wheezing episode and their correlation with prognosis. We recruited 52 sole RV- and 11 sole RSV-affected children with a severe first wheezing episode. Peripheral blood mononuclear cells (PBMCs) were isolated during acute illness and 2 weeks later and stimulated in vitro with anti-CD3/anti-CD28. Culture medium samples were analyzed for 56 different cytokines by multiplex ELISA. Recurrences were prospectively followed for 4 years. In adjusted analyses, the cytokine response from PBMCs in the RV group was characterized by decreased expression of interleukin 1 receptor antagonist (IL-1RA), interleukin 1 beta (IL-1β), and monocyte chemoattractant protein-1 (MCP-1) and increased expression of eosinophil chemotactic protein 2 (eotaxin-2), thymus- and activation-regulated chemokine (TARC), and epithelial-derived neutrophil-activating peptide 78 (ENA-78) in the acute phase and increased expression of fractalkine in the convalescent phase compared to those in the RSV group. An analysis of the change in cytokine expression between study points revealed an increased expression of fractalkine and IL-1β and decreased expression of I-309 (CCL1) and TARC in the RV group compared to those in the RSV group.. Considering hospitalization time, a significant non-adjusted group × cytokine interaction was observed in the levels of interferon gamma (IFN-γ), macrophage-derived chemokine (MDC), IL-1RA, and vascular endothelial growth factor (VEGF), indicating that a higher expression of cytokine was associated with shorter hospitalization time in the RSV group but not in the RV group. A significant interaction was also found in interleukin 6 (IL-6), but the cytokine response was not associated with hospitalization time in the RSV or RV group. In the RV group, increased expression of I-309 (CCL1) and TARC was associated with fewer relapses within 2 months, and decreased expression of interleukin 13 (IL-13) and increased expression of I-309 (CCL1) were associated with less relapses within 12 months. Differences in cytokine response from PBMCs were observed between RV- and RSV-induced first severe wheezing episode. Our findings also reveal new biomarkers for short- and medium-term prognosis in first-time wheezing children infected with RV or RSV.

LUNG AND GUT MICROBIOME DURING EARLY-LIFE RESPIRATORY SYNCYTIAL VIRUS INFECTION

LUNG AND GUT MICROBIOME DURING EARLY-LIFE RESPIRATORY SYNCYTIAL VIRUS INFECTION