Background:Mucoid sputum is common in pediatric patients with lower respiratory tract infection (LRTI) and can exacerbate cough, contribute to difficulty in expectoration and dyspnea, and even cause suffocation. Although ambroxol hydrochloride and clenbuterol hydrochloride oral solution [AHCHOS (or Yitanjing)] is widely used in pediatric practice, high-quality real-world evidence comparing it with conventional expectorant therapies such as ambroxol hydrochloride injection (AHI) remains limited. This study aimed to investigate the efficacy and safety of AHCHOS in pediatric patients with LRTI complicated with mucoid sputum. Methods:This multicenter, non-randomized observational study included 407 hospitalized pediatric patients with LRTI complicated by mucoid sputum across 30 institutions in China. Patients received AHCHOS (n=254) or AHI (n=153) based on clinical judgment and guardian preference. Inclusion criteria comprised age ≤14 years, confirmed LRTI diagnosis, and clinically significant sputum symptoms. Respiratory symptoms were assessed using a composite symptom score and a visual analog scale (VAS) at baseline and Day 7. Safety was evaluated through routine clinical monitoring, including vital signs, physical examination, and laboratory assessments. Results:The baseline features, including family history of respiratory disease (P<0.001) and type of the episode (P=0.02), differed between groups. The decline in total respiratory symptom score was greater in the AHCHOS group than in the AHI group at D7 (-4.35±2.25 vs. -3.56±1.89; P<0.001), as was the decrease in corresponding percentage (-77%±30% vs. -65%±28%; P<0.001). Regarding subscales, the decrease in cough (P<0.001), sputum amount (P=0.03), and wheezing rale (P=0.008) scores was significantly greater in the AHCHOS group than in the AHI group at D7, but the expectoration difficulty score was not (P=0.90). Meanwhile, the decrease in VAS score for self-reported symptom severity was greater in the AHCHOS group than in the AHI group at D7 (-4.12±2.04 vs. -3.51±1.78; P=0.006). Moreover, no adverse reactions were reported in either group. Conclusions:AHCHOS was associated with improved respiratory symptom outcomes and was well tolerated in pediatric patients with LRTI complicated by mucoid sputum.

Background:Although randomized controlled trials (RCTs) have confirmed the mucolytic efficacy of ambroxol hydrochloride solution for inhalation (AHSI) in selected cohorts, their stringent exclusion criteria often omit children with comorbidities and complex presentations encountered in routine practice. Consequently, real-world evidence is needed to evaluate the effectiveness and safety of AHSI in a broader, clinically representative pediatric population with acute lower respiratory tract infections (ALRTIs). This study therefore aimed to assess the real-world effectiveness, safety, and nebulizer compatibility of a 7-day AHSI regimen added to standard care in a large, multicenter cohort of hospitalized pediatric patients with ALRTI. Methods:This real-world, multicenter, open-label, single-arm study enrolled hospitalized patients aged ≥6 months with ALRTI (acute bronchitis, bronchiolitis, or pneumonia) and symptom duration <7 days across 62 centers in China (April 2021-April 2022). Key inclusion criteria included a cough score ≥2 (0-4 scale), tenacious sputum, and difficulty expectorating. Major exclusions comprised severe pneumonia, bronchial asthma, interstitial lung disease, significant hepatic or renal dysfunction [alanine aminotransferase (ALT) >1.5× upper limit of normal (ULN), total bilirubin (TBil) or serum creatinine (Scr) > ULN], other severe comorbidities, known hypersensitivity to ambroxol, or recent trial participation. Participants received weight-based doses of nebulized AHSI twice daily for 7 days as add-on to standard care. Follow-up visits occurred at day 4 and day 7 (end of treatment). Primary endpoints were the cough improvement rate (defined by a reduction in cough score) and the overall clinical response rate (investigator-assessed improvement). Secondary endpoints included changes from baseline in cough, throat rales, and pulmonary auscultation scores. Safety assessments comprised monitoring of adverse events (AEs) (coded with MedDRA), vital signs, and laboratory tests (hematology, biochemistry, urinalysis) at baseline and day 7. Results:A total of 2,599 children were enrolled [full analysis set (FAS)]. At baseline, mean age was 3.60±2.50 years, 57.6% were male, and symptom scores were: cough 2.10±0.30, throat sputum 1.65±0.59, lung auscultation 1.44±0.70. In the FAS, the cough improvement rate was 96.73% [95% confidence interval (CI): 96.05-97.41] and the clinical response rate was 94.73% (95% CI: 93.87-95.59). All symptom scores decreased significantly from baseline to day 7 (P<0.001). Drug-related AEs (DRAEs) occurred in 0.39% of patients, predominantly mild-to-moderate rash, transient liver enzyme elevations, and gastrointestinal events; no serious DRAEs were reported. Outcomes were consistent across pneumonia and bronchitis subgroups and across various nebulizer types. Conclusions:This large real-world study demonstrated that a 7-day course of AHSI, added to standard care, was associated with clinically meaningful improvements in respiratory symptoms and a favorable safety profile in children with ALRTI. The consistent effects across disease subtypes and nebulizer devices underscore the practical utility of AHSI in diverse pediatric settings. While the single-arm design limits causal inference, these findings provide robust real-world evidence supporting AHSI as an effective expectorant option. Prospective confirmation through RCTs will further define its role in first-line therapy.

The trends in allergic comorbidities secondary to the environmental variations in China remain unclear. We aimed to determine the variation of allergic comorbidities and polysensitization among asthma and/or rhinitis patients in the past decade. We assessed two nationally representative cross-sectional datasets from 2008 to 2009 and 2018 to 2019, which enrolled 2322 and 2353 patients, respectively. Over the present 10-year study period, the prevalence of allergic symptoms and allergen sensitivity among patients with multiple sensitivities in the 2018-2019 cohort was significantly higher than that in the 2008-2009 cohort, especially for mites, pollen, and animal allergens. The comorbidity rates of asthma, allergic rhinitis, conjunctivitis, and eczema were significantly increased in the 2018-2019 cohort. Also in that cohort, IgE polysensitization was significantly associated with the coexistence of asthma and rhinitis, and the number of IgE-reactive allergens was significantly associated with the number of multimorbidities. Use of an air-conditioner and carpet in the home, and keeping pet were linked to the risk of polysensitization. Our findings suggest an increase in the comorbidity rate and multimorbid polysensitized phenotype of allergic diseases in China. Asthma occurred in both cohorts more frequently with coexisting allergies than as a single entity.

BackgroundPulmonary thromboembolism is rare in children, but can be life-threatening. Timely diagnosis and treatment of pulmonary thromboembolism are crucial for reducing mortality associated with pulmonary thromboembolism in children. While guidelines for pulmonary thromboembolism in adults are available, guidelines for standardized diagnosis and management of pulmonary thromboembolism in children are not. This expert consensus aims to provide recommendations for the management of pulmonary thromboembolism in children based on the current best available evidence.Data sourcesFollowing the World Health Organization Handbook for Guideline Development, the expert panel consisted of 30 members from different clinical areas. The panel identified clinical questions through systematic reviews and expert discussions, systematically reviewed evidence on pulmonary thromboembolism in children, and evaluated the quality of the evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Using the GRADE Evidence to Decision Framework, the panel made recommendations, considering the effects of interventions, resource use, values and preferences, equity, acceptability, and feasibility.ResultsThe epidemiology, classification, and pathophysiology characteristics are summarized. The expert panel developed 33 recommendations addressing 20 questions related to diagnosis steps, treatment approaches such as anticoagulant therapy, thrombolysis therapy, catheter-based interventional therapy, surgical embolectomy, multidisciplinary team, and treatment of patients with comorbidities, prognosis, education, as well as follow-up. Among these, 18 are weak recommendations based on very low quality evidence, and 15 are good practice statements.ConclusionsThe expert panel provided recommendations for pulmonary thromboembolism in children based on available evidence, which was generally low in quality and volume. The panel urges further research on early identification and diagnosis strategies, preventive and therapeutic regimens, and long-term management for pulmonary thromboembolism.

This is a multicenter retrospective study aimed to evaluate the concordance between nucleic acid testing and targeted next-generation sequencing (tNGS) for etiologic detection, and to identify potential risk factors for severe community-acquired pneumonia (SCAP), thereby providing evidence for precision clinical management. We retrospectively analyzed 191 pediatric Community-Acquired Pneumonia(CAP) cases positive for bocavirus by tNGS from April 2023 to June 2025. Etiologic concordance and coinfection patterns were evaluated. Univariate and multivariate logistic regression identified independent risk factors for SCAP. 191 children were included. Significant heterogeneity was observed among the four centers in age distribution, SCAP incidence, imaging findings, and treatment patterns (P < 0.05). Children’s Hospital, Zhejiang University School of Medicine (ZCH) reported the highest SCAP incidence (50.0

Objective Ambroxol hydrochloride and clenbuterol hydrochloride oral solution (AHCHOS) is an agent with mucolytic and bronchodilator functions, but its clinical application in child patients with lower respiratory tract infections (LRTI) and symptoms of mucoid sputum needs more investigation. This study aimed to investigate efficacy of AHCHOS, its influencing factors, and effect on quality of life in these patients. Methods This study enrolled 254 hospitalized child patients with LRTI and symptoms of mucoid sputum receiving AHCHOS. Results Total cough of respiratory symptom (QS) score and QS scores of each subscale (cough, amount of sputum, difficulty in expectoration, and wheeling rale) on the 7th day (D7) were decreased than those at baseline (all P < 0.001). After multivariate logistic regression analysis, non parental guardian status (OR = 25.641, P = 0.020), respiratory rate (OR = 1.075, P = 0.019), and neutrophil percentage (OR = 1.034, P = 0.026) were independently related to higher possibility of absolute value of change of total QS score>5. Quality of life visual analog scale score on D7 was reduced than that at baseline (P < 0.001). Medication compliance was 98.00% on the 4th day, 92.68% on D7, 76.00% on the 14th day, and 75.95% on the 28th day. No adverse event occurred. Conclusion AHCHOS alleviates respiratory symptoms and improves quality of life with good safety in child patients with LRTI and symptoms of mucoid sputum, which is more beneficial for those with elevated respiratory rate, higher neutrophil percentage, and nonparental guardians.

Purpose:To evaluate the association of ambroxol hydrochloride and clenbuterol hydrochloride oral solution (AHCHOS) with respiratory symptom improvement and safety in Chinese children with pneumonia using real-world data. Methods:A propensity score-matched (PSM) cohort study was conducted. Children patients (≤14 years) with a diagnosis of pneumonia between May, 2018 and July, 2019 were considered as the study population. The main outcome of interest was the overall rate of improvement of respiratory symptoms in treatment groups with or without AHCHOS at day 7 using respiratory symptom scores (QS) and Visual Analog Scale (VAS) score of severity of respiratory signs. Secondary end points include medication adherence assessment and safety assessment. Results:A total of 3103 children with a diagnosis of pneumonia were included. After propensity score matching, a sample of 1428 patients was analyzed. AHCHOS use was associated with greater improvement in cough score (p=0.01) and day 7 clinical sign improvement rate (p=0.03) compared with no AHCHOS use. Exploratory subgroup analyses suggested larger differences in children aged 3-6 years and in selected severity strata. Medication adherence assessmentdid not differ significantly between groups at days 4, 7, 14, and 28. Adverse events were similar between groups. Conclusion:In this real-world propensity score-matched analysis, AHCHOS use was associated with improved respiratory symptom outcomes in children with pneumonia and appeared to have an acceptable safety profile. These findings should be interpreted as observational and hypothesis-generating. Trial Registration Number:The study was registered at Chinese Clinical Trial Registry (https://www.chictr.org.cn/, ChiCTR1800015818).

Obesity, a rising global health issue, has been linked to the exacerbation of asthma, increasing both the risk of onset and disease severity. High-fat diet (HFD) has been shown to influence immune responses and worsen asthma in murine models, although the exact mechanisms remain unclear. In our study, we found that HFD significantly reduced the population of regulatory T cells (Tregs) in the lungs and led to increased eosinophilic inflammation in asthma. HFD was linked to alterations in lipid metabolism, particularly through the activation of the lipogenic enzyme acetyl-CoA carboxylase (ACC1) and inhibition of fatty acid oxidation. Additionally, treatment with Etomoxir, a CPT-1a inhibitor, diminished Treg proportions and Foxp3 expression. We also revealed that the E3 ubiquitin ligase ITCH, which regulates Treg function, was downregulated at the protein level under HFD conditions, despite unchanged mRNA levels. Overall, our research findings highlight the impact of high-fat diets on Treg function and immune regulation, providing insights for potential therapeutic strategies targeting lipid metabolism in inflammatory diseases like asthma.

Background While allergen-specific immunotherapy (AIT) is recognized as an effective treatment, its efficacy varies widely. However, whether clinical response trajectories to AIT differ among individuals and influence its effectiveness has not been investigated. Objective This study aimed to characterize real-world clinical response trajectories to three-year AIT (3y-AIT). Methods We conducted a retrospective multicenter study across 53 centers to identify clinical response trajectories in patients with house dust mite allergic asthma and rhinitis undergoing three-year AIT. The efficacy of AIT was primarily assessed using the Visual Analog Scale (VAS) for allergic symptoms at 4 time points: baseline (before AIT), and at 1, 2, and 3 years of treatment. Clustering analysis based on VAS changes at these time points was used to define response trajectories. Initial analysis was performed using data from 52 centers (Alliance cohort), and validation was conducted using data from a separate center (Guangzhou cohort). Results In the Alliance cohort, 4 distinct clinical response trajectories were identified. Cluster 1 showed symptom worsening in the first year, with no improvement by year 3. Cluster 2 exhibited symptom deterioration in the second year, followed by significant recovery and a positive response by year 3. Clusters 3 and 4, characterized by higher and lower baseline symptom severity, respectively, demonstrated marked improvement after 3 years of AIT. In the Guangzhou cohort, a similar pattern of 4 response trajectories was observed: higher baseline symptom severity and family tobacco exposure were key features of Cluster 1 (p < 0.001), while Cluster 2 had the highest rate of respiratory infections (>1/year, p < 0.001). Despite these distinct trajectories, first-year effectiveness emerged as an ideal predictor of the 3-year AIT response, with an AUC of 0.75. Conclusion This study identified 4 primary treatment response trajectories to 3-year AIT in daily clinical practice, highlighting the heterogeneous nature of AIT responses among individuals. Notably, first-year effectiveness appears to be an ideal predictor of the 3-year AIT outcome.

Pleural effusion is a common symptom in children with respiratory diseases, with infections being the leading cause. Currently, the use of metagenomic next-generation sequencing (mNGS) for pleural effusion has not been fully evaluated in pediatric lung disease patients. Patients who had undergone mNGS for pleural effusion were included in the study. Patients were categorized into a clinically useful group and a not clinically useful group on the basis of their clinical data, laboratory results, and mNGS results. A total of 48 children were included in this study. The number of positive mNGS results was 32/48 (66.7

BACKGROUND:Physical activity participation among children with asthma is highly variable and cannot be explained by disease severity alone. Understanding distinct patterns of activity engagement and their underlying mechanisms may help inform more tailored support strategies. OBJECTIVE:To identify distinct physical activity profiles in children with asthma and to explore the lived experiences and family processes underlying these profiles using a mixed-methods design. METHODS:An explanatory sequential mixed-methods study was conducted in two phases. In the quantitative phase, 243 children with asthma aged 6-17 years were consecutively recruited between March 2024 and February 2025 from respiratory outpatient clinics of two tertiary hospitals in Zhejiang Province, China. Measures assessed physical activity, asthma control, breathlessness-related fear, perceived physical competence, and parental activity support. Person-centered profile modeling was used to identify distinct profiles. In the qualitative phase, 16 child-parent dyads (4 per profile) were purposively selected for semi-structured interviews between June and September 2025. Joint display analysis was used to integrate quantitative patterns with lived experiences. RESULTS:Four distinct profiles were identified. Profile 1, Fearful Avoiders (14.4%), showed the lowest activity, poorest asthma control, highest symptom fear, and lowest physical competence; qualitative findings suggested a self-reinforcing cycle of fear, avoidance, and reduced confidence. Profile 2, Unsupported Potentials (15.6%), showed predominantly moderate activity, the lowest parental support, and predominantly partial asthma control; interviews suggested that symptom stability was often interpreted as "good enough," leading families to disengage from active lifestyle support. Profile 3, Struggling Strivers (21.4%), maintained moderate activity despite elevated symptom fear and intermediate psychosocial outcomes; qualitative data suggested that activity was often sustained under peer and family pressure rather than through genuine confidence. Profile 4, Supported Thrivers (48.6%), demonstrated the most favorable pattern, with higher activity, better asthma control, lower fear, stronger perceived competence, and greater parental support. External validation supported the clinical relevance of the profiles, with significant between-profile differences in depression, anxiety, quality of life, and exercise adherence (all p < .001). CONCLUSION:Physical activity participation in children with asthma appears to be shaped by interacting physiological, psychological, and family processes rather than by disease severity alone. Similar activity levels may reflect very different underlying mechanisms, including disengagement, fear-driven persistence, or adaptive self-management. These findings suggest that support for physical activity in pediatric asthma may need to be tailored to profile-specific behavioral and family mechanisms.

Objective:To investigate the present state of adherence to subcutaneous specific immunotherapy (SCIT) in children sensitized to dust mites, explore the factors contributing to the cessation of SCIT in this demographic, and provide scientific evidence aimed at improving compliance and efficacy of SCIT in pediatric patients. Methods:A retrospective analysis was conducted on clinical data of pediatric patients who received treatment at our desensitization center between January 2017 and December 2023. These children exhibited sensitivity to dust mites and were diagnosed with allergic asthma, allergic rhinitis, or other allergic diseases, subsequently undergoing SCIT therapy. The fulfillment of the SCIT regimen was evaluated, and the factors contributing to treatment cessation were analyzed. Results:A total of 680 children were included in the study. Of these, 424 children (62.35%) successfully completed the entire treatment regimen (total course ≥3 years), whereas 256 children (37.65%) chose to discontinue the treatment prematurely (total course <3 years). The reasons for the cessation of SCIT, ranked from most to least common, included efficacy issues (54.69%), drug intolerance (18.75%), family-related factors (10.94%), the repercussions of the COVID-19 pandemic (6.64%), influence from other diseases (6.25%) and various other reasons. The primary reason for discontinuation within the first month was family factors (46.15%), while within six months, it was drug intolerance (40.82%), and after 6 months, efficacy issues (68.04%) became the leading cause. Conclusion:The uncertain efficacy and intolerance to the medication predominantly hinder compliance with SCIT in children, while family factors serve as the main reason for discontinuation within the first month. By enhancing parental comprehension and awareness of SCIT, standardizing operational protocols, and promptly addressing any adverse reactions, compliance with SCIT could be significantly improved.

Exposure to subinhibitory concentrations of β-lactam antibiotics has been shown to induce the biofilm formation of microorganisms, but the underlying mechanisms remain poorly understood. This study aims to explore the effect of different concentrations of amoxicillin-clavulanate, the most commonly used antibiotic in pediatrics, on the biofilm formation of Haemophilus influenza (H. influenzae) in vitro and to explore the underlying mechanisms. The effect of amoxicillin-clavulanate on the in vitro biofilm formation was assessed by crystal violet assay, colony counts, MTT colorimetric method, scanning electron microscopy, and confocal laser scanning microscopy. Integrated transcriptomics and metabolomics analyses were performed to identify key genes and metabolites. Our findings revealed that 1/2 MIC of amoxicillin-clavulanate significantly enhanced H. influenzae ATCC 49247 biofilm formation in vitro, while simultaneously reducing culturable bacterial counts and metabolic activity of biofilm-embedded bacteria. When exposed to 1/2 MIC of amoxicillin-clavulanate, the biofilm ultrastructure was altered, with an increase in biofilm structure, a decrease in bacteria embedded within the biofilms with abnormal bacterial morphology. Transcriptomics identified 118 differentially expressed genes (DEGs), comprising 62 upregulated and 56 downregulated genes. Metabolomics identified 21 differentially expressed metabolites (DEMs), with 13 upregulated and 8 downregulated. Integrated transcriptomics and metabolomics implicated amino sugar and nucleotide sugar metabolism as a key regulatory pathway. This study has provided novel insights into the relationship between a commonly prescribed pediatric antibiotic and H. influenzae biofilm formation, elucidating the underlying mechanisms, emphasizing the critical importance of judicious antibiotic use and clinical consideration of subinhibitory antibiotic effects, particularly in pediatric populations.

Flexible bronchoscopy(FB)is a highly versatile and effec-tive diagnostic and therapeutic tool with a pivotal position in respiratory medicine.Indeed,the flexible bronchoscope,with its capability to visualize both the upper and lower airways,is indispensable for managing neonates,infants,and children with diverse respiratory diseases[1].Despite the use of guide-lines on pediatric flexible bronchoscopy(PFB)from the Euro-pean Respiratory Society[2],the American Thoracic Society[3]and a Chinese guideline released in 2009[4]and updated in 2018[5],considerable variation exists.This is related to the provision of facilities,accessibility of equipment,and imple-mentation.Standards remain to be fully unified.

Background:In the wake of COVID-19, a resurgence of Mycoplasma pneumoniae pneumonia (MPP) has emerged globally since mid-2023. However, the clinical manifestations and immune responses following infection vary across different age groups of pediatric patients (infants, preschoolers and school-aged children), increasing the complexity of diagnosis and treatment. Methods:This study retrospectively analyzed serum cytokine levels in 40 healthy children and 87 MPP patients, with additional cytokine profiling of bronchoalveolar lavage fluid (BALF) in severe cases, combining KEGG pathway analysis to investigate age-related immune patterns. SARS-CoV-2 antibody levels were further detected in these MPP patients, followed by Spearman correlation analysis to assess their correlation with cytokines in MPP children. Results:Age-specific cytokine patterns emerged in MPP children. In 0-2 years, cytokines enriched in IL-17, TLR, and TNF pathways were upregulated in MPP groups compared to controls, while in 6-12 years, cytokines enriched in TLR, RLR, and JAK-STAT pathways were downregulated in MPP groups. Serum patterns in 3-5 years resembled those in 0-2 years, but BALF aligned with 6-12 years. SARS-CoV-2 IgG positively correlated with TWEAK, IL-22, IL-16, IL-12p40, CCL7, and CD152 in 0-2 years (P < 0.05), but negatively with CCL13 in 6-12 years (P < 0.01). Conclusion:Overall, the immune pattern in children with MPP is age-specific and severity-dependent. Higher levels of SARS-CoV-2 IgG are associated with a more robust and mature anti-infective immune response in younger MPP patients, while in older children, besides providing immune memory against pathogens, SARS-CoV-2 IgG also appears to plant a landmine of immune exhaustion.

Bronchial asthma is a common chronic respiratory disease in children. For many years, concerns about exercise-induced bronchoconstriction have limited physical activity in this population, with negative consequences for both physical and mental health. Recent evidence indicates that exercise should be incorporated into the daily routine of children with asthma, with appropriately prescribed programs shown to improve disease control, lung function, and quality of life. This study aims to systematically describe the safety, benefits and key factors of exercise for children with asthma. Initiated by the National Clinical Research Center for Child Health, this set of recommendations was developed by a multidisciplinary team of 17 experts. A comprehensive Literature search was conducted across PubMed, Embase, Cochrane and other databases, yielding 64 studies that met inclusion criteria up to May 2025. The Oxford Centre for Evidence-Based Medicine 2011 levels of evidence were used to evaluate evidence quality. Two rounds of expert voting were conducted using Delphi methodology to formulate final recommendations on key clinical topics. Recommendations were formulated across nine core domains: exercise safety, exercise-related benefits, pre-exercise screening, exercise prescription design, plan adjustment and progression, pre-exercise preparation, exercise monitoring, outcome assessment and the management of exercise-induced bronchoconstriction. Specific guidance is offered on individualized exercise planning based on asthma control status, physical fitness, exercise habits and environmental factors. Recommendations also address appropriate modalities of aerobic, resistance and flexibility training, strategies for monitoring intensity and progression and both pharmacologic and non-pharmacologic approaches to exercise-induced bronchoconstriction prevention and management. These recommendations provide scientific and practical guidance for the development and implementation of individualized exercise prescriptions in children with asthma. Moreover, they highlight the importance of multidisciplinary collaboration and reinforce exercise as an integral component of asthma management. Further high-quality clinical research is needed to optimize exercise protocols and evaluate long-term outcomes.

Presentation of cases Dr.Ye(Pulmonologist):A seven-year-old boy was admitted to this hospital due to persistent cough. The patient was in good health until two weeks before the current presentation,when he developed a mild,non-pro-ductive cough without wheezing,shortness of breath,chest pain,or hemoptysis.Initially,his parents did not take him to the hospital and administered oral cefixime and montelukast for four days without improvement.Then chest computed tomography(CT)scan at a local hospital revealed bilat-eral pulmonary inflammation with left-lung hyperlucency(Fig.1a,b).

Background Respiratory syncytial virus (RSV) is the leading global cause of respiratory infections and is responsible for about 3 million hospitalizations and more than 100,000 deaths annually in children younger than 5 years, representing a major global healthcare burden. There is a great unmet need for new agents and universal strategies to prevent RSV infections in early life. A multidisciplinary consensus development group comprising experts in epidemiology, infectious diseases, respiratory medicine, and methodology aims to develop the current consensus to address clinical issues of RSV infections in children. Data sources The evidence searches and reviews were conducted using electronic databases, including PubMed, Embase, Web of Science, and the Cochrane Library, using variations in terms for “respiratory syncytial virus”, “RSV”, “lower respiratory tract infection”, “bronchiolitis”, “acute”, “viral pneumonia”, “neonatal”, “infant” “children”, and “pediatric”. Results Evidence-based recommendations regarding diagnosis, treatment, and prevention were proposed with a high degree of consensus. Although supportive care remains the cornerstone for the management of RSV infections, new monoclonal antibodies, vaccines, drug therapies, and viral surveillance techniques are being rolled out. Conclusions This consensus, based on international and national scientific evidence, reinforces the current recommendations and integrates the recent advances for optimal care and prevention of RSV infections. Further improvements in the management of RSV infections will require generating the highest quality of evidence through rigorously designed studies that possess little bias and sufficient capacity to identify clinically meaningful end points.

Objectives: Viruses are the main infectious agents of acute respiratory infections (ARIs) in children. We aim to describe the changes in epidemic characteristics of viral ARIs in outpatient children before and during the COVID-19 pandemic. Patients and methods: From 2017 to 2022, the results of viral detection in oral pharyngeal swabs in 479,236 children with ARIs in the outpatient department of Children's Hospital, Zhejiang University School of Medicine, were retrospectively analyzed. Viral antigens, including adenovirus (ADV), influenza A (FLUA), influenza B (FLUB) and respiratory syncytial virus (RSV) were detected by the colloidal gold method. Results: The median age was 3.4 (1.6-5.6) years. Among all the children, 159,895 cases (33.4 %) were positive for at least one virus. The total positive rate for ADV, FLUA and FLUB during the pandemic period was lower than during the pre-pandemic period in every season (pre-pandemic period vs. pandemic period11.7 % vs. 4.7 %, 13.9 % vs. 9.2 %, 7.0 % vs. 5.2 %, respectively, with overall p value < 0.001). However, the positive rate fir RSV was not significantly different between the pre-pandemic period and the pandemic period (5.6 % vs. 5.8 %, p = 0.117). Atypical timing of RSV (summer-autumn 2021) and FLUA (summer 2022) was noted. Conclusions: Public health interventions for different pathogens are maximally effective. While positive rates for ADV, FLUA and FLUB decreased during the COVID-19 pandemic period, positive rates for RSV remained similar. In RSV and FLUA, off-season outbreaks were observed. Measures need to be taken to protect children from possible infection surges due to immunity debt having accrued over the last three years.