Daily Respiratory Research Analysis

BACKGROUND: Respiratory syncytial virus (RSV) disease burden among adults aged <65 years is not well documented. We aimed to estimate the hospitalization burden of RSV in adults aged 18 to 64 years in high-income countries. METHODS: We conducted a systematic review (PROSEPRO: CRD42022377741) to identify studies reporting estimates of RSV hospitalization burden in the study population. For each study included, we followed a 2-step statistical approach to adjust for RSV case underascertainment related to the use of clinical specimen and diagnostic test. Random effects meta-analysis was conducted to estimate RSV hospitalization and mortality burden. We further compared estimates between the 18- to 64-year age group in this study and the ≥65-year age group in our previous study using the same methodology. RESULTS: Based on 8 studies, the adjusted annual RSV-associated hospitalization rate was 48 per 100 000 (95% CI, 31-77) in adults aged 18 to 64 years. According to 12 studies, more than three-quarters of RSV-associated hospitalized adults had at least 1 comorbidity: adults aged 50 to 64 years with asthma, congestive heart failure, chronic obstructive pulmonary disease, coronary artery disease, or diabetes and adults aged 18 to 49 years with congestive heart failure or diabetes had comparable RSV hospitalization rates to those aged ≥65 years without these comorbidities. An overall 6.1% (95% CI, 5.2%-7.1%) of adults aged 18 to 64 years with RSV-associated hospitalization died in the hospital (3 studies). CONCLUSIONS: Adults aged 18 to 64 years with certain comorbidities have substantial RSV hospitalization burden comparable to those aged ≥65 years without these comorbidities and could be the additional target populations for RSV vaccination programs.

BACKGROUND: Pulmonary tuberculosis (PTB) is increasingly recognized as a major precursor of chronic obstructive pulmonary disease (COPD). However, validated tools to predict the risk of COPD following PTB cure remain limited. Early identification of individuals at high risk is essential to facilitate targeted follow-up and preventive interventions. METHODS: This prospective cohort study was conducted at Hunan Chest Hospital. Adults with newly diagnosed PTB who completed standard anti-tuberculosis treatment were enrolled between January and June 2023 and followed until June 2025. Follow-up assessments were performed monthly during the first 3 months, quarterly from months 6 to 12, and every 6 months thereafter, with standardized evaluation of respiratory symptoms and lung function. Incident COPD was defined as a post-bronchodilator FEV RESULTS: During follow-up, 83 of 324 participants (25.6%) developed COPD. Older age (≥65 years), active smoking, cavitary PTB, invasive fungal disease, dyspnea, an elevated systemic immune-inflammation index (SII), and a reduced CD4⁺/CD8⁺ T-cell ratio were independently associated with COPD development. A prediction model incorporating these seven variables demonstrated good discrimination, with an area under the receiver operating characteristic curve of 0.806 (95% CI: 0.751-0.861), and satisfactory calibration. Internal validation yielded a bootstrap-corrected concordance index of 0.787, indicating favorable clinical utility across a broad range of decision thresholds. CONCLUSION: More than one-quarter of patients developed COPD after PTB cure, highlighting the substantial burden of post-tuberculosis respiratory sequelae. The proposed prediction model enables individualized risk stratification and may support early surveillance and targeted preventive strategies, extending post-TB care beyond microbiological cure to long-term respiratory outcomes.

Airborne transmission of severe acute respiratory syndrome coronavirus 2 in enclosed, mechanically ventilated hospital wards remains poorly characterized. In February 2025, a coronavirus disease cluster involving 17 individuals occurred across multiple rooms in a sealed Japanese hospital ward. Several infected individuals had no documented close contact with the index patient, raising concerns about ventilation-related airflow-induced inter-room aerosol transmission. A multimodal environmental investigation was conducted via (1) CO2 decay experiments to quantify air change rates (ACHs), (2) particulate matter (PM)2.5 aerosol dispersion measurements using fog as a surrogate tracer, and (3) computational fluid dynamics (CFD) simulations to visualize airflow and scalar transport. Measurements were taken in the index room (Room A), corridor, and adjacent Rooms B-D under closed- and open-door conditions. Opening the patient room door significantly increased indoor ACHs (3.29/h → 4.01/h, p = 0.030) and allowed CO2 tracer gas to escape into the corridor. In the PM2.5 dispersion experiment, aerosols released in Room A were detected within the room, corridor, and neighboring rooms, with the highest out-of-room aerosol burden observed at the corridor sensor (area under the curve = 2.6 × 105 μg·s/m3). PM2.5 and PM10 concentrations were strongly correlated (r = 0.9997), revealing intermediate-sized particles capable of longer-range transport. CFD simulations reproduced key qualitative features of the experiments, including tracer accumulation within curtain-enclosed compartments, delayed leakage through the doorway, and downstream transport toward the corridor. Inter-room aerosol transport can occur in sealed, mechanically ventilated wards without natural ventilation or structural openings between rooms. Opening doors improves in-room ventilation and promotes aerosol leakage, revealing a trade-off between the dilution and contamination of shared spaces. Architectural elements such as privacy curtains contribute to airflow stagnation and uneven aerosol removal. Effective infection control strategies must incorporate airflow pathway management and localized filtration to prevent unintended aerosol migration in mechanically ventilated healthcare settings.