Respiratory syncytial virüs infections in neonates and infants

Comparison of characteristics of children hospitalized for respiratory syncytial virus infection during the pre- and post-COVID-19 eras: a multicenter retrospective study

BACKGROUND

Respiratory syncytial virus (RSV), a leading cause of lower respiratory tract infection (LRTI) among children, has resurged in the form of endemic or even pandemic in many countries and areas after the easing of COVID-19 containment measures. This study aimed to investigate the differences in epidemiological and clinical characteristics of children hospitalized for RSV infection during pre- and post-COVID-19 eras in Yunnan, China.

METHODS

A total of 2553 pediatric RSV inpatients from eight hospitals in Yunnan were retrospectively enrolled in this study, including 1451 patients admitted in 2018-2019 (pre-COVID-19 group) and 1102 patients admitted in 2023 (post-COVID-19 group). According to the presence or absence of severe LRTI (SLRTI), patients in the pre- and post-COVID-19 groups were further divided into the respective severe or non-severe subgroups, thus analyzing the risk factors for RSV-associated SLRTI in the two eras. Demographic, epidemiological, clinical, and laboratory data of the patients were collected for the final analysis.

RESULTS

A shift in the seasonal pattern of RSV activity was observed between the pre-and post-COVID-19 groups. The peak period of RSV hospitalizations in the pre-COVID-19 group was during January-April and October-December in both 2018 and 2019, whereas that in the post-COVID-19 group was from April to September in 2023. Older age, more frequent clinical manifestations (fever, acute otitis media, seizures), and elevated laboratory indicators [neutrophil-to-lymphocyte ratio (NLR), c-reactive protein (CRP), interleukin 6 (IL-6), co-infection rate] were identified in the post-COVID-19 group than those in the pre-COVID-19 group (all P < 0.05). Furthermore, compared to the pre-COVID-19 group, the post-COVID-19 group displayed higher rates of SLRTI and mechanical ventilation, with a longer length of hospital stay (all P < 0.05). Age, low birthweight, preterm birth, personal history of atopy, underlying condition, NLR, IL-6 were the shared independent risk factors for RSV-related SLRTI in both pre- and post-COVID-19 groups, whereas seizures and co-infection were independently associated with SLRTI only in the post-COVID-19 group.

CONCLUSIONS

An off-season RSV endemic was observed in Yunnan during the post-COVID-19 era, with changed clinical features and increased severity. Age, low birthweight, preterm birth, personal history of atopy, underlying condition, NLR, IL-6, seizures, and co-infection were the risk factors for RSV-related SLRTI in the post-COVID-19 era.

Comparative analysis of human respiratory syncytial virus evolutionary patterns during the COVID-19 pandemic and pre-pandemic periods

The COVID-19 pandemic has resulted in the implementation of strict mitigation measures that have impacted the transmission dynamics of human respiratory syncytial virus (HRSV). The measures also have the potential to influence the evolutionary patterns of the virus. In this study, we conducted a comprehensive analysis comparing genomic variations and evolving characteristics of its neutralizing antigens, specifically F and G proteins, before and during the COVID-19 pandemic. Our findings showed that both HRSV A and B exhibited an overall chronological evolutionary pattern. For the sequences obtained during the pandemic period (2019-2022), we observed that the HRSV A distributed in A23 genotype, but formed into three subclusters; whereas the HRSV B sequences were relatively concentrated within genotype B6. Additionally, multiple positively selected sites were detected on F and G proteins but none were located at neutralizing antigenic sites of the F protein. Notably, amino acids within antigenic site III, IV, and V of F protein remained strictly conserved, while some substitutions occurred over time on antigenic site Ø, I, II and VIII; substitution S389P on antigenic site I of HRSV B occurred during the pandemic period with nearly 50% frequency. However, further analysis revealed no substitutions have altered the structural conformations of the antigenic sites, the vial antigenicity has not been changed. We inferred that the intensive public health interventions during the COVID-19 pandemic did not affect the evolutionary mode of HRSV.

Development of Photonic Multi-Sensing Systems Based on Molecular Gates Biorecognition and Plasmonic Sensors: The PHOTONGATE Project

This paper presents the concept of a novel adaptable sensing solution currently being developed under the EU Commission-founded PHOTONGATE project. This concept will allow for the quantification of multiple analytes of the same or different nature (chemicals, metals, bacteria, etc.) in a single test with levels of sensitivity and selectivity at/or over those offered by current solutions. PHOTONGATE relies on two core technologies: a biochemical technology (molecular gates), which will confer the specificity and, therefore, the capability to be adaptable to the analyte of interest, and which, combined with porous substrates, will increase the sensitivity, and a photonic technology based on localized surface plasmonic resonance (LSPR) structures that serve as transducers for light interaction. Both technologies are in the micron range, facilitating the integration of multiple sensors within a small area (mm2). The concept will be developed for its application in health diagnosis and food safety sectors. It is thought of as an easy-to-use modular concept, which will consist of the sensing module, mainly of a microfluidics cartridge that will house the photonic sensor, and a platform for fluidic handling, optical interrogation, and signal processing. The platform will include a new optical concept, which is fully European Union Made, avoiding optical fibers and expensive optical components.

Respiratory Syncytial Virus Infections in Neonates: A Persisting Problem

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infections in young infants. It is an enveloped, single-stranded, nonsegmented, negative-strand RNA virus, a member of the family Pneumoviridae. Globally, RSV is responsible for 2.3% of deaths among neonates 0-27 days of age. Respiratory syncytial virus infection is most common in children aged below 24 months. Neonates present with cough and fever. Respiratory syncytial virus-associated wheezing is seen in 20% infants during the first year of life of which 2-3% require hospitalization. Reverse transcriptase polymerase chain reaction (RT-PCR) gives fast results and has higher sensitivity compared with culture and rapid antigen tests and are not affected by passively administered antibody to RSV. Therapy for RSV infection of the LRT is mainly supportive, and preventive measures like good hygiene and isolation are the mainstay of management. Standard precautions, hand hygiene, breastfeeding and contact isolation should be followed for RSV-infected newborns. Recent AAP guidelines do not recommend pavilizumab prophylaxis for preterm infants born at 29-35 weeks without chronic lung disease, hemodynamically significant congenital heart disease and coexisting conditions. RSV can lead to long-term sequelae such as wheezing and asthma, associated with increased healthcare costs and reduced quality of life.

Qingfei oral liquid alleviates RSV-induced lung inflammation by promoting fatty-acid-dependent M1/M2 macrophage polarization via the Akt signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Respiratory syncytial virus (RSV) is a common pathogen that causes lower respiratory tract disease in infants and the elderly, and no vaccination is presently available. Qingfei oral liquid (QF), a traditional Chinese medicine formula, has been shown in clinic to have anti-inflammatory properties.

AIM OF THE STUDY

The present study investigated whether QF can suppress RSV-induced lung inflammation in mice models via fatty acid-dependent macrophage polarization.

MATERIAL AND METHODS

BALB/c mice were given a low, medium, or high dose of QF intragastrically for four consecutive days following RSV infection. The lung inflammatory status was assessed using H&E staining and cytokine assays. The active components of QF and fatty acid metabolism were analyzed using ultra-high-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS). A lipid metabolism-related pathway was found through network pharmacology and molecular docking investigations. Western blotting assays were used to determine the levels of ATP-citrate lyase (ACLY), peroxisome proliferation-activated receptor alpha (PPAR), Akt protein kinase B and its phosphorylated form in Akt signaling. Flow cytometry was used to quantify the number of macrophage subtypes (M1/M2), and immunohistochemistry was used to examine the expression of inducible nitric oxide synthase (iNOS) and arginase-1 (Arg-1).

RESULTS

In the lung tissues of RSV-infected mice, QF suppressed the transcription of pro-inflammatory proteins such as interleukin-1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), and interleukin-6 (IL-6), while increasing the level of anti-inflammatory factors such as interleukin-10 (IL-10). The alterations in metabolic enzyme activity mediated by Akt signaling were linked to QF's significant reduction in lung fatty acid accumulation. Lower ACLY expression and higher PPAR expression were found after QF treatment, showing that these two enzymes were downstream targets of Akt signaling, controlling fatty acid synthesis (FAS) and fatty acid oxidation (FAO), respectively. The reprogramming of fatty acid metabolism resulted in the polarization of macrophages from M1 to M2, with lower expression of iNOS and higher expression of Arg-1. Additionally, application of an Akt agonist (SC-79) reduced QF's anti-inflammatory effects by increasing FAS and decreasing macrophage polarization.

CONCLUSIONS

QF inhibited Akt-mediated FAS and polarized M1 to M2 macrophages, resulting in an anti-inflammatory impact.

Integrated Network Pharmacology and Lipidomics to Reveal the Inhibitory Effect of Qingfei Oral Liquid on Excessive Autophagy in RSV-Induced Lung Inflammation

Background: Respiratory syncytial virus (RSV) can cause varying degrees of lung inflammation in children. Qingfei Oral Liquid (QF) is effective in treating childhood RSV-induced lung inflammation (RSV-LI) in clinics, but its pharmacological profiles and mechanisms remain unclear. Methods: This study combined network Pharmacology, lipidomics, pharmacodynamics, and pathway validation to evaluate the therapeutic mechanisms of QF. Using Cytoscape (v3.8.2) and enrichment analyses from the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO), a global view of the putative compound-target-pathway network was created. The corresponding lipidomic profiles were then used to detect differently activated lipids, revealing the metabolic pathway, using ultra-high-performance liquid chromatography linked to hybrid Quadrupole-Exactive Orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap MS). Meanwhile, the in vivo efficiency of QF, the enrichment pathway, and the excessive autophagy inhibition mechanisms were validated in RSV-infected mice models. Results: The network pharmacology results demonstrated 117 active compounds acted directly upon 101 core targets of QF against RSV-LI. The most significantly enriched pathway was the PI3K/Akt/mTOR signaling pathway (p < 0.05). In addition, untargeted lipidomics were performed, and it was revealed that higher lung levels of DAG 30:0, DAG 30:5, DAG 32:0, DAG 16:0_18:0, DAG 17:0_17:0, DAG 34:1, DAG 36:0, DAG 36:1 in the RSV-LI group were decreased after QF administration (FDR < 0.05, FC > 1.2). Lipin-1, a key enzyme in DAG synthesis, was increased in the RSV-LI mouse model. Animal experiments further validated that QF inhibited the PI3K/Akt/mTOR signaling pathway, with lower lung levels of phosphorylated PI3K, AKT and mTOR, as well as its related proteins of lipin-1 and VPS34 (p < 0.01). Finally, pharmacodynamic investigations indicated that QF reduced airway inflammation caused by excessive autophagy by decreasing lung levels of RSV F and G proteins, Beclin-1, Atg5, and LC3B II, IL-1 and TNF-α (p < 0.05). Conclusion: Lipidomic-based network pharmacology, along with experimental validation, may be effective approaches for illustrating the therapeutic mechanism of QF in the treatment of RSV-LI.

Probiotics against Viral Infections: Current Clinical Trials and Future Perspectives

Viral infections represent a major health problem worldwide. Due to the wide variety of etiological agents and their increasing resistance to anti-virals and antibiotics treatments, new strategies for effective therapies need to be developed. Scientific evidence suggests that probiotics may have prophylactic and therapeutic effects in viral diseases. Indeed, these microorganisms interact harmoniously with the intestinal microbiota and protect the integrity of the intestinal barrier as well as modulate the host immune system. Currently, clinical trials with probiotics have been documented in respiratory tract infections, infections caused by human immunodeficiency viruses, herpes, human papillomavirus and hepatic encephalopathy. However, the benefits documented so far are difficult to extrapolate, due to the strain-dependent effect. In addition, the dose of the microorganism used as well as host characteristics are other parameters that should be consider when advocating the use of probiotics to treat viral infections. This review addresses the scientific evidence of the efficacy of probiotics in clinical strains perspective in viral infectious diseases in the last 10 years.

Cribra orbitalia is correlated with the meningo-orbital foramen and is vascular and developmental in nature

Cribra orbitalia is a phenomenon with interdisciplinary interest. However, the etiology of cribra orbitalia remains unclear. Recently, the appearance of cribra orbitalia was identified as vascular in nature. This study assessed the relationship between anatomical variation of vasculature, as determined by the presence of meningo-orbital foramina, and the presence of cribra orbitalia in 178 orbits. Cribra orbitalia was identified in 27.5% (49:178) of orbits (22.7%, 35:154 adult orbits and 58.3%, 14:24 subadult orbits) and meningo-orbital foramina were identified in 65.8% (100:152) of orbits. Among the 150 total intact adult orbits (i.e., orbital roof and posterior orbits both intact), cribra orbitalia was found in 35 (23.3%). Of these 35 occurrences of cribra orbitalia, 32 (91.4%) had the concurrent finding of a meningo-orbital foramen. However, in the absence of the meningo-orbital foramen, cribra orbitalia was only found in three sides out of the total sample of intact orbits (3:150; 2.0%). Fisher's exact test revealed that the presence of cribra orbitalia and the meningo-orbital foramen were statistically dependent variables (p = .0002). Visual evidence corroborated statistical findings-vascular impressions joined cribra orbitalia to meningo-orbital foramina. This study identifies that individuals who possess a meningo-orbital foramen are anatomically predisposed to developing cribra orbitalia. Conversely, cribra orbitalia is unlikely to occur in an individual who does not possess a meningo-orbital foramen. Thus, the antecedent of cribra orbitalia is both vascular and developmental in nature. This report represents an important advancement in the understanding of cribra orbitalia-there is an anatomical predisposition to the development of cribra orbitalia.

Performance evaluation of EuDx™ ufPCR Flu & RSV detection kit for detection of influenza A/B and respiratory syncytial virus

EuDx™ ufPCR Flu & RSV Detection Kit (EUDIPIA, Chungcheongbuk-do, Republic of Korea) is a recently developed molecular assay for simultaneously detecting influenza A/B and respiratory syncytial virus (RSV). We evaluated this assay in a clinical setting and demonstrated its excellent performance for diagnosing influenza A/B and RSV infections.

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.

Method of Hydration for Infants Admitted With Bronchiolitis: Physician or Parental Choice?

Objectives This study examines the practice patterns with respect to the technique of non-oral hydration of infants admitted with bronchiolitis at one Canadian tertiary care institution. Additionally, the authors assess the infants' parents' attitudes regarding hydration through a nasogastric (NG) tube instead of an intravenous (IV) line. Methods A retrospective chart review was conducted for all infants admitted with bronchiolitis from May 1, 2016, to April 30, 2018, with a focus on the method of hydration, investigation with chest radiography, and use of IV antibiotics. Parents of infants who received IV fluids during the admission were surveyed by mail to assess their perceptions surrounding their child's experience with IV fluid therapy as well as their attitudes toward NG hydration, particularly in cases of difficult IV access. Results Of the 101 hospitalized infants, 54 received IV fluids and four received NG fluids. Of the 54 eligible for the survey, 17 completed surveys were returned. Parents were likely to consider NG hydration if suggested by their pediatrician. The proportion was extremely or very likely to consider this intervention increased from 29% in a generic situation to 53% in a scenario where there was more than one unsuccessful IV attempt (p=0.03). Conclusions In the institution studied, NG hydration was rarely used. Parents seemed receptive to the idea of NG hydration as an alternative, particularly when IV access is difficult.

The emergence of subgenotype ON-1 of Human orthopneumovirus type A in Riyadh, Saudi Arabia: A new episode of the virus epidemiological dynamic

Lower respiratory tract infections caused by Human orthopneumovirus are still a threat to the pediatric population worldwide. To date, the molecular epidemiology of the virus in Saudi Arabia has not been adequately charted. In this study, a total of 205 nasopharyngeal aspirate samples were collected from hospitalized children with lower respiratory tract symptoms during the winter seasons of 2014/15 and 2015/16. Human orthopneumovirus was detected in 89 (43.4%) samples, of which 56 (27.3%) were positive for type A and 33 (16.1%) were positive for type B viruses. The fragment that spans the two hypervariable regions (HVR1 and HVR2) of the G gene of Human orthopneumovirus A was amplified and sequenced. Sequence and phylogenetic analyses have revealed a genotype shift from NA1 to ON-1, which was prevalent during the winter seasons of 2007/08 and 2008/09. Based on the intergenotypic p-distance values, ON-1 was reclassified as a subgenotype of the most predominant genotype GA2. Three conserved N-glycosylation sites were observed in the HVR2 of Saudi ON-1 strains. The presence of a 23 amino acid duplicated region in ON-1 strains resulted in a higher number of O-glycosylation sites as compared to other genotypes. The data presented in this report outlined the replacement of NA1 and NA2 subgenotypes in Saudi Arabia with ON-1 within 7 to 8 years. The continuous evolution of Human orthopneumovirus through point mutations and nucleotide duplication may explain its ability to cause recurrent infections.

Host Components Contributing to Respiratory Syncytial Virus Pathogenesis

Respiratory syncytial virus (RSV) is the most prevalent viral etiological agent of acute respiratory tract infection. Although RSV affects people of all ages, the disease is more severe in infants and causes significant morbidity and hospitalization in young children and in the elderly. Host factors, including an immature immune system in infants, low lymphocyte levels in patients under 5 years old, and low levels of RSV-specific neutralizing antibodies in the blood of adults over 65 years of age, can explain the high susceptibility to RSV infection in these populations. Other host factors that correlate with severe RSV disease include high concentrations of proinflammatory cytokines such as interleukins (IL)-6, IL-8, tumor necrosis factor (TNF)-α, and thymic stromal lymphopoitein (TSLP), which are produced in the respiratory tract of RSV-infected individuals, accompanied by a strong neutrophil response. In addition, data from studies of RSV infections in humans and in animal models revealed that this virus suppresses adaptive immune responses that could eliminate it from the respiratory tract. Here, we examine host factors that contribute to RSV pathogenesis based on an exhaustive review of in vitro infection in humans and in animal models to provide insights into the design of vaccines and therapeutic tools that could prevent diseases caused by RSV.

Childhood iron deficiency anemia leads to recurrent respiratory tract infections and gastroenteritis

Anemia affects approximately 30% of children all over the world. Acute respiratory tract infections (ARTI), urinary tract infections (UTI) and gastroenteritis (GE) are common infectious entities in children. Here, we assessed the association between anemia and development of recurrent ARTI, UTI, and GE in children. This was a case-control study in hospitalized 2–5 years old children in Professorial Pediatric Unit at Teaching Hospital Anuradhapura, Sri Lanka. An 18-month follow up was done to assess the risk factors for the development of recurrent ARTI, GE, UTI, and control presented without infections. Further, 6-month follow up done after 3-month iron supplementation to assess the occurrence of recurrences. Blood Hb concentration was measured using Drabking’s reagent. Logistic regression was used to find the risk factors for the development of recurrences. In ARTI, 121/165 (73.3%), GE, 88/124 (71%), UTI 46/96 (47.9%) and control 40/100 (40%) were having anemia. Initial ARTI group, recurrent ARTI was 24 (14.5%, p = 0.03); initial GE group: recurrent GE was 14 (11.3%, p = 0.03), recurrent ARTI was 11 (8.9%, p = 0.04); initial UTI group, development of; recurrent UTI was 8 (8.3%, p = 0.04); control, recurrent ARTI was 11 (11%, p = 0.03). Following 3-month iron supplementation reduction of recurrences was significant: initial ARTI recurrent ARTI in 90%, recurrent GE in 77.7%; initial GE recurrent GE in 83.3%, recurrent ARTI in 80%; initial UTI recurrent ARTI in 71.4% and control recurrent ARTI in 88.8%. Iron deficiency is a major type of anemia and anemic children are more prone to develop recurrent ARTI and GE. Once iron deficiency being corrected the rate of recurrent ARTI and GE was reduced. This would be a boost for policy developers to implement strategies at the community level to prevent iron deficiency in children to reduce ARTI and GE recurrences.

Bronchiolitis Admissions in a Lebanese Tertiary Medical Center: A 10 Years' Experience

Bronchiolitis and more specifically respiratory syncytial virus (RSV) bronchiolitis is a leading cause of global childhood morbidity and mortality. Despite the previous identification of possible risk factors associated with the severity of bronchiolitis, the data from Lebanon remains limited. We described the burden of bronchiolitis hospitalizations in children under 5 years of age in a tertiary care center in Lebanon from October 2004 to October 2014 and identified the risk factors associated with severe bronchiolitis. This was a retrospective cohort study conducted at the American University of Beirut Medical Center. Records of children younger than 5 years of age admitted with a diagnosis of bronchiolitis were reviewed. More than half the patients were RSV positive. RSV bronchiolitis was found to be significantly associated with longer hospital stay compared to children with non-RSV bronchiolitis (P = 0.007). Children exposed to smoking had an increased risk for longer hospital stay (P = 0.002) and were more likely to require ICU admission (P < 0.001) and supplemental oxygen (P = 0.045). Congenital heart disease was found to be a significant risk factor for severe bronchiolitis (P < 0.005). Conclusion: Patients with RSV bronchiolitis had a longer hospital stay compared to patients with non-RSV bronchiolitis. Exposure to smoking was associated with a more severe and complicated RSV infection. Congenital heart disease was the only risk factor significantly associated with all markers of bronchiolitis disease severity.