Daily Respiratory Research Analysis

Wastewater surveillance of respiratory pathogens can provide timely estimates of viral activity and disease trends in a population. Indoor air surveillance could be used similarly with some advantages but remains largely unvalidated at the community-scale. Here, an indoor air surveillance program was employed as part of public health environmental surveillance in Chicago, Illinois, USA. Ten air samplers were placed in healthcare and congregate living settings across the city. Weekly air samples were evaluated for influenza A, influenza B, respiratory syncytial virus, and SARS-CoV-2 over two respiratory virus seasons (2023-2025). Citywide, aggregated air sample positivity and viral load were closely correlated with local clinical case and wastewater surveillance data across all respiratory viruses. Virus trends in air data often preceded clinical and wastewater, although this varied across pathogens and respiratory virus seasons. Further, whole-genome sequencing of SARS-CoV-2 showed close correlation of variant proportions across all datasets. At the building-scale, air samples obtained from a single sampling device provided efficient respiratory virus surveillance, with respiratory pathogen levels mirroring citywide clinical surveillance data. These data demonstrate that air surveillance can provide respiratory virus case and variant trend data at a building or community-scale, serving as an alternative or complementary tool for public health environmental surveillance.

The Global consensus definition of acute respiratory distress syndrome (ARDS) broadened the syndrome to include patients on high-flow nasal cannula and hypoxia as defined by the ratio of the saturation of oxygen to fraction of inhaled oxygen (SFR). We sought to compare the incidence and outcomes of ARDS under the 2012 Berlin versus 2023 Global definitions, and to examine the relationship between SFR-derived categories of severity and mortality, in a prospective cohort of critically ill patients with sepsis. Of the 950 included patients, 466 (49%) met criteria for ARDS under the Global definition and 427 (45%) met criteria for ARDS under the Berlin definition during the 6-day follow-up period. Among patients with ARDS, the Global definition allowed for ARDS qualification a median of 3.0 h earlier than the Berlin definition. Mortality was comparable between the Global and Berlin definitions at onset but substantially lower for patients who never went onto meet the Berlin definition. SFR was predictive of 30-day mortality and exhibited moderate correlation with the ratio of partial pressure of oxygen to fraction of inhaled oxygen (PFR). Our work establishes an increased incidence and modestly decreased time to diagnosis of ARDS under the Global definition and supports the prognostic validity of SFR.

Respiratory syncytial virus (RSV) remains the leading cause of hospitalization in young children. A bivalent pre-fusion (preF) protein RSV vaccine was licensed for pregnant persons in 2023 (Abrysvo, Pfizer), but the impact of RSV maternal immunization on maternal-fetal immunity has not been well characterized. We analyze neutralizing antibody responses, binding antibodies, and antibody affinity maturation in 58 unvaccinated and 49 vaccinated pregnant individuals and their infants. Maternal RSV vaccination induces robust neutralizing antibodies against both RSV-A2 and RSV-B1 strains, with geometric mean titers 8-fold and 13.4-fold higher, respectively, in vaccinated versus unvaccinated participants. Vaccination significantly enhances binding antibodies to RSV-preF protein (5.2-fold higher) and antibody affinity maturation (3.7-fold higher). High-quality RSV-specific antibodies are efficiently transferred across the placenta. However, early preterm infants showed reduced antibody transfer efficiency compared with full-term infants. These findings demonstrate that maternal RSV vaccination generates high-quality, affinity-matured transferable antibodies that provide passive immunity to infants.