A Comparison of State-Specific Pediatric Emergency Medical Facility Recognition Programs, 2020.

OBJECTIVES: Prior research suggests that the presence of state-specific pediatric emergency medical facility recognition programs (PFRPs) is associated with high emergency department (ED) pediatric readiness. The PFRPs aim to improve the quality of pediatric emergency care, but individual state programs differ. We aimed to describe the variation in PFRP characteristics and verification requirements and to describe the availability of pediatric emergency care coordinators (PECCs) in states with PFRPs. METHODS: In mid-2020, we collected information about each PFRP from 3 sources: the state Emergency Medical Services for Children (EMSC) website, the EMSC Innovation and Improvement Center website, or via communication with the state's EMSC program manager. For each state with a PFRP, we documented program characteristics, including program start date, number of tiers, whether participation was required/optional, and requirements for verification. RESULTS: Overall, we identified 17 states with active PFRPs. Five states had only 1 tier or level of recognition whereas the others had multiple. All programs did require presence of a PECC for verification. However, some PRFPs with multiple verification tiers did not require presence of a PECC to achieve each level of verification. In states with PFRPs, EDs with higher total visit volumes, a separate pediatric ED area, located in the Northeast, and earlier program start date were all more likely to have a PECC. CONCLUSIONS: There is variation in state PFRPs, although all prioritize the presence of a PECC. We encourage further research on the effect of different aspects of PFRPs on patient outcomes.

Emergency Department and Health Care System Factors Associated with Telehealth Innovation During the COVID-19 Pandemic.

Objective: Telehealth capacity may be an important component of pandemic response infrastructure. We aimed to examine changes in the telehealth use by the US emergency departments (EDs) during COVID-19, and to determine whether existing telehealth infrastructure or increased system integration were associated with increased likelihood of use. Methods: We analyzed 2016-2020 National ED Inventory (NEDI)-USA data, including ED characteristics and nature of telehealth use for all US EDs. American Hospital Association data characterized EDs' system integration. An ordinary least-squares regression model obtained one-step-ahead forecast of the expected proportion of EDs using telehealth in 2020 based on growth observed from 2016 to 2019. Among EDs without telehealth in 2019, we used logistic regression models to examine whether system membership or existing telehealth infrastructure were associated with odds of innovation in telehealth use in 2020, accounting for ED characteristics. Results: Of 4,038 EDs responding to telehealth questions in 2019 and 2020 (73% response rate), 3,015 used telehealth in 2020. Telehealth use by US EDs increased more than expected in 2020 (2016: 58%, 2017: 61%, 2018: 65%, 2019: 67%, 2020: 74%, greater than predicted 71%, p = 0.004). Existing telehealth infrastructure was associated with increased telehealth innovation (OR = 1.88, 95% CI: 1.49-2.36), whereas hospital system membership was not (odds ratio [OR] = 1.00, 95% confidence interval [CI]: 0.80-1.25). Conclusions: Telehealth use by US EDs in 2020 grew more than expected and preexisting telehealth infrastructure was associated with increased innovation in its use. Preparation for future pandemic responses may benefit from considering strategies to invest in local infrastructure to facilitate technology adoption and innovation.

Case-control study of exclusive breast feeding and severe bronchiolitis in the United States.

BACKGROUND: Bronchiolitis is a major cause of infant illness, with few known modifiable risk factors. Breast feeding may reduce risk of severe bronchiolitis, but the association of exclusive vs. partial breast feeding with severe bronchiolitis is unclear. OBJECTIVE: To estimate the association of exclusive vs. partial breast feeding during ages 0-2.9 months with bronchiolitis hospitalisation during infancy. METHODS: We conducted a case-control study as a secondary analysis of two prospective US cohorts in the Multicenter Airway Research Collaboration. Cases were enrolled in a 17-centre study of infants hospitalised for bronchiolitis during 2011-2014 (n = 921). Controls were enrolled in a five-centre study of healthy infants during 2013-2014 and 2017 (n = 719). Breast feeding history during ages 0-2.9 months was collected by parent interview. Among breastfed infants, the association of exclusive vs. partial breast feeding with odds of bronchiolitis hospitalisation was estimated using a multivariable logistic regression model adjusted for demographic variables, parental asthma history, and early-life exposures. As a secondary analysis, we estimated the associations of exclusive, predominant, and occasional breast feeding vs. no breast feeding with the odds of bronchiolitis hospitalisation. RESULTS: Among 1640 infants, the prevalence of exclusive breast feeding was 187/921 (20.3%) among cases and 275/719 (38.3%) among controls. Exclusive vs. partial breast feeding was associated with 48% reduced odds of bronchiolitis hospitalisation (adjusted odds ratio [OR] 0.52, 95% confidence interval [CI] 0.39, 0.69). In the secondary analysis, exclusive vs. no breast feeding was associated with 58% reduced odds of bronchiolitis hospitalisation (OR 0.42, 95% CI 0.23, 0.77), whereas predominant breast feeding (OR 0.77, 95% CI 0.37, 1.57) and occasional breast feeding (OR 0.98, 95% CI 0.57, 1.69) were not associated with meaningfully reduced odds of bronchiolitis hospitalisation. CONCLUSION: Exclusive breast feeding had a strong protective association against bronchiolitis hospitalisation.

Association between household cleaning product exposure in infancy and development of recurrent wheeze and asthma.

OBJECTIVE: Household chemicals may act as irritants in the lungs; however, their association with recurrent wheeze and asthma in children remains controversial. We aimed to investigate if household cleaning product exposure in infancy is associated with recurrent wheezing and asthma development in children. METHODS: We analyzed data from two cohorts: MARC-35 consisting of 815 children with history of severe bronchiolitis in infancy, and MARC-43 consisting of 525 healthy children in infancy. Frequency of use of cleaning product at the child's home during infancy was collected via telephone interview with parents. Outcomes were recurrent wheezing by age 3 years and asthma diagnosis at age 6 years. RESULTS: In MARC-35, there was no association between cleaning product exposure in infancy and recurrent wheeze (adjusted HR = 1.01 [95% CI 0.66-1.54] for 4-7 days/week exposure frequency), nor asthma (adjusted OR = 0.91 [95% CI 0.51-1.63]). In MARC-43, there was also no association between cleaning product exposure in infancy and recurrent wheeze (adjusted HR = 0.69 [95% CI 0.29-1.67] for 4-7 days/week exposure frequency). CONCLUSION: We found no association between household cleaning product exposure in infancy and later development of recurrent wheeze or asthma, even among children who are at high risk for asthma due to history of severe bronchiolitis.

Availability of Pediatric Emergency Care Coordinators in US Emergency Departments in 2018.

OBJECTIVES: In 2007, the US Institute of Medicine recommended that every emergency department (ED) appoint pediatric emergency care coordinators (PECCs). Despite this recommendation, our national surveys showed that few (17%) US EDs reported at least 1 PECC in 2015. This number increased slightly to 19% in 2016 and 20% in 2017. The current study objectives were to determine the following: percent of US EDs with at least 1 PECC in 2018, factors associated with availability of at least 1 PECC in 2018, and factors associated with addition of at least 1 PECC between 2015 and 2018. METHODS: In 2019, we conducted a survey of all US EDs to characterize emergency care in 2018. Using the National ED Inventory-USA database, we identified 5514 EDs open in 2018. This survey collected availability of at least 1 PECC in 2018. A similar survey was administered in 2016 and identified availability of at least 1 PECC in 2015. RESULTS: Overall, 4781 (87%) EDs responded to the 2018 survey. Among 4764 EDs with PECC data, 1037 (22%) reported having at least 1 PECC. Three states (Connecticut, Massachusetts, and Rhode Island) had PECCs in 100% of EDs. The EDs in the Northeast and with higher visit volumes were more likely to have at least 1 PECC in 2018 (all P < 0.001). Similarly, EDs in the Northeast and with higher visit volumes were more likely to add a PECC between 2015 and 2018 (all P < 0.05). CONCLUSIONS: The availability of PECCs in EDs remains low (22%), with a small increase in national prevalence between 2015 and 2018. Northeast states report a high PECC prevalence, but more work is needed to appoint PECCs in all other regions.

U.S. Emergency Department Telepsychiatry Use in 2019.

Introduction: Although many emergency departments (EDs) receive telehealth services for psychiatry, or telepsychiatry, to manage acute psychiatric emergencies, national research on the usage of ED telepsychiatry is limited. To investigate ED telepsychiatry usage in the pre-COVID-19 era, we surveyed a sample of EDs receiving telepsychiatry in 2019, as a follow-up to a survey targeted to similar EDs in 2017. Methods: All U.S. EDs open in 2019 (n = 5,563) were surveyed to characterize emergency care. A more in-depth second survey on telepsychiatry use (2019 ED Telepsychiatry Survey) was then sent to 235 EDs. Of these EDs, 130 were randomly selected from those that reported telepsychiatry receipt in 2019, and 105 were selected based on their participation in a similar survey in 2017 (2017 ED Telepsychiatry Survey). Results: Of the 235 EDs receiving the 2019 Telepsychiatry Survey, 192 (82%) responded and 172 (90% of responding EDs) confirmed 2019 telepsychiatry receipt. Of these, five were excluded for missing data (analytic samplen = 167). Telepsychiatry was the only form of emergency psychiatric services for 92 (55%) EDs. The most common usage of telepsychiatry was for admission or discharge decisions (82%) and transfer coordination (70%). The most commonly reported telepsychiatry mental health consultants were psychiatrists or other physician-level mental health professionals (74%). Discussion: With telepsychiatry as the only form of psychiatric services for most telepsychiatry-receiving EDs, this innovation fills a critical gap in access to emergency psychiatric care. Further research is needed to investigate the impact of the COVID-19 pandemic on usage of ED telepsychiatry.

Pediatric Telehealth Use in U.S. Emergency Departments in 2019.

Objectives: Little is known about the recent usage of pediatric telehealth across all emergency departments (EDs) in the United States. Building upon our prior work, we aimed to characterize the usage of ED pediatric telehealth in the pre-COVID-19 era. Methods: The 2019 National ED Inventory-USA survey characterized all U.S. EDs open in 2019. Among EDs reporting receipt of pediatric telehealth services, we selected a random sample (n = 130) for a second survey on pediatric telehealth usage (2019 ED Pediatric Telehealth Survey). We also recontacted a random sample of EDs that responded to a prior, similar 2017 ED Pediatric Telehealth Survey (n = 107), for a total of 237 EDs in the 2019 ED Pediatric Telehealth Survey sample. Results: Overall, 193 (81%) of the 237 EDs responded to the 2019 Pediatric Telehealth Survey. There were 149 responding EDs that confirmed pediatric telehealth receipt in 2019. Among these, few reported ever having a pediatric emergency medicine (PEM) physician (10%) or pediatrician (9%) available for emergency care. Although 96% of EDs reported availability of pediatric telehealth services 24 h per day, 7 days per week, the majority (60%) reported using services less than once per month and 20% reported using services every 3-4 weeks. EDs most frequently used pediatric telehealth to assist with placement and transfer coordination (91%). Conclusions: Most EDs receiving pediatric telehealth in 2019 had no PEM physician or pediatrician available. Most EDs used pediatric telehealth services infrequently. Understanding barriers to assimilation of telehealth once adopted may be important to enable improved access to pediatric emergency care expertise.

Development of a unified national database of primary percutaneous coronary intervention centers with co-located emergency departments, 2020.

BACKGROUND: Although primary percutaneous coronary intervention (pPCI) is the preferred intervention for ST-elevation myocardial infarction (STEMI), not all patients are admitted directly to an emergency department (ED) with 24/7/365 pPCI capabilities. This is partly due to a lack of a national system of known pPCI-capable EDs. Our objective was to create a unified, national database of confirmed 24/7/365 pPCI centers co-located in hospitals with EDs. METHODS: We compiled all hospitals designated as Chest Pain Centers with Primary PCI by the American College of Cardiology's (ACC) National Clinical Data Registry (NCDR), all STEMI Receiving Centers designated by the American Heart Association's (AHA) Mission: Lifeline registry, and all state-designated pPCI-capable hospitals and designation criteria from state departments of health. We matched ACC, AHA, and state-designated facilities to those in the 2019 National ED Inventory (NEDI)-USA database to identify all EDs in pPCI-capable hospitals. RESULTS: Overall, 467 hospitals were recognized as Chest Pain Centers with Primary PCI by ACC, 293 hospitals were recognized as being STEMI Receiving Centers by AHA, and 827 hospitals were confirmed to be pPCI-capable by state designations and operated 24/7/365. Together, there were 1,178 EDs (21% of 5,587 total) co-located in pPCI-capable hospitals operating 24/7/365. CONCLUSIONS: There is substantial heterogeneity in cardiac systems of care, with large regional systems existing alongside local state-led initiatives. We created a unified national database of confirmed 24/7/365 pPCI centers co-located in hospitals with EDs. This data set will be valuable for future cardiac systems research and improving access to pPCI.

Late Pre-term Infants with Severe Bronchiolitis and Risk of Asthma by Age 5 Years.

In a prospective, multicenter cohort of infants hospitalized with bronchiolitis, we found infants born late pre-term (ie, gestational age of 34-36.9 weeks) had 35% higher odds of having asthma by age 5 years compared with infants born at full-term.

A Regional Intervention to Appoint Pediatric Emergency Care Coordinators in New England Emergency Departments.

OBJECTIVE: The aim of this study was to describe our expansion of a Massachusetts grassroots initiative-to increase the appointment of pediatric emergency care coordinators (PECCs) in emergency departments (EDs)-to all 6 New England states. METHODS: We conducted annual surveys of all EDs in New England from 2015 to 2020 regarding 2014 to 2019, respectively. Data collection included ED characteristics. The intervention from 2018 to 2019 relied on principles of self-organization and collaboration with local stakeholders including state Emergency Medical Services for Children agencies, American College of Emergency Physician state chapters, and Emergency Nursing Association state chapters to help encourage appointment of at least 1 PECC to every ED. Most ED leadership were contacted in person at regional meetings, by e-mail and/or telephone. We reached out to each individual ED to both educate and encourage action. RESULTS: Survey response rates were greater than 85% in all years. From 2014 to 2016, less than 30% of New England EDs reported a PECC. In 2017, 51% of EDs in New England reported a PECC, whereas in 2019, 91% of New England EDs reported a PECC. All other ED characteristics remained relatively consistent from 2014 to 2019. CONCLUSIONS: We successfully expanded a Massachusetts grassroots initiative to appoint PECCs to all of New England. Through individual outreach, and using principles of self-organization and creating collaborations with local stakeholders, we were able to increase the prevalence of PECCs in New England EDs from less than 30% to greater than 90%. This framework also led to the creation of a New England-wide PECC network and has fostered ongoing collaboration and communication throughout the region.

Detection of Respiratory Syncytial Virus or Rhinovirus Weeks After Hospitalization for Bronchiolitis and the Risk of Recurrent Wheezing.

BACKGROUND: In severe bronchiolitis, it is unclear if delayed clearance or sequential infection of respiratory syncytial virus (RSV) or rhinovirus (RV) is associated with recurrent wheezing. METHODS: In a 17-center severe bronchiolitis cohort, we tested nasopharyngeal aspirates (NPA) upon hospitalization and 3 weeks later (clearance swab) for respiratory viruses using PCR. The same RSV subtype or RV genotype in NPA and clearance swab defined delayed clearance (DC); a new RSV subtype or RV genotype at clearance defined sequential infection (SI). Recurrent wheezing by age 3 years was defined per national asthma guidelines. RESULTS: Among 673 infants, RSV DC and RV DC were not associated with recurrent wheezing, and RSV SI was rare. The 128 infants with RV SI (19%) had nonsignificantly higher risk of recurrent wheezing (hazard ratio [HR], 1.31; 95% confidence interval [CI], .95-1.80; P = .10) versus infants without RV SI. Among infants with RV at hospitalization, those with RV SI had a higher risk of recurrent wheezing compared to children without RV SI (HR, 2.49; 95% CI, 1.22-5.06; P = .01). CONCLUSIONS: Among infants with severe bronchiolitis, those with RV at hospitalization followed by a new RV infection had the highest risk of recurrent wheezing.

Availability of Pediatric Emergency Care Coordinators in United States Emergency Departments.

OBJECTIVE: To determine the availability of pediatric emergency care coordinators (PECCs) in US emergency departments (EDs) in 2015, and to determine the change in availability of PECCs in US EDs from 2015 to 2017. STUDY DESIGN: As part of the National Emergency Department Inventory-USA, we administered a survey to all 5326 US EDs open in 2015; all 5431 in 2016; and all 5489 in 2017. Through these surveys, we assessed the availability of PECCs. Descriptive statistics characterized EDs with and without PECCs; multivariable logistic regressions identified characteristics independently associated with PECC availability. RESULTS: Among the 4443 (83%) EDs with 2015 data, 763 (17.2%) reported the availability of at least 1 PECC. The states with the largest proportion of EDs with PECCs were Delaware (78%, 7/9 EDs) and Maryland (48%, 20/42 EDs), and no PECCs were reported in Mississippi, North Dakota, or Wyoming. Availability of a PECC was associated (P < .001) with larger annual total ED visit volume and a dedicated pediatric ED area. Compared with the 17.2% of EDs reporting a PECC in 2015, 833 (18.6%) reported 1 in 2016, and 917 (19.8%) reported 1 in 2017 (P < .001). CONCLUSIONS: Availability of at least 1 PECC increased slightly (2.6%) between 2015 and 2017, but ∼80% of EDs continue without one.

Distance From Freestanding Emergency Departments to Nearby Emergency Care.

STUDY OBJECTIVE: The number of freestanding emergency departments (EDs) has increased rapidly in the United States, and there is concern that such entities are located near existing EDs rather than in areas lacking emergency care. In 2018, the Medicare Payment Advisory Commission recommended a reduction in Medicare reimbursement rates to freestanding EDs located within 6 miles of the nearest hospital-based ED. We aim to assess the potential effect of this proposal. METHODS: Using the 2016 National Emergency Department Inventory-USA database, we identified the locations and visit volumes of all US freestanding EDs. Using QGIS, we mapped the distances from all freestanding EDs to both the nearest hospital-based ED and to the nearest ED (either hospital-based or freestanding ED). RESULTS: We collected location information for all 5,375 EDs open in 2016. Of these EDs, 609 (11%) were freestanding. Few freestanding EDs (1.4%) were located in rural areas and only 11% were located in areas with a median household income of less than $43,000. Overall, 460 freestanding EDs (76%) were within 6 miles of the nearest hospital-based ED, and these had 5.3 million total patient visits, whereas those greater than 6 miles away had 2.6 million visits. CONCLUSION: We found that most freestanding EDs (76%) are within 6 miles of the nearest hospital-based ED, and most visits (67%) to freestanding EDs are to those within that proximity, indicating that many freestanding EDs would be affected by this Medicare Payment Advisory Commission proposal, if implemented.

Screening for Health-Related Social Needs of Emergency Department Patients.

STUDY OBJECTIVE: There has been increasing attention to screening for health-related social needs. However, little is known about the screening practices of emergency departments (EDs). Within New England, we seek to identify the prevalence of ED screening for health-related social needs, understand the factors associated with screening, and understand how screening patterns for health-related social needs differ from those for violence, substance use, and mental health needs. METHODS: We analyzed data from the 2018 National Emergency Department Inventory-New England survey, which was administered to all 194 New England EDs during 2019. We used descriptive statistics to compare ED characteristics by screening practices, and multivariable logistic regression models to identify factors associated with screening. RESULTS: Among the 166 (86%) responding EDs, 64 (39%) reported screening for at least one health-related social need, 160 (96%) for violence (including intimate partner violence or other violent exposures), 148 (89%) for substance use disorder, and 159 (96%) for mental health needs. EDs reported a wide range of social work resources to address identified needs, with 155 (93%) reporting any social worker availability and 41 (27%) reporting continuous availability. CONCLUSION: New England EDs are screening for health-related social needs at a markedly lower rate than for violence, substance use, and mental health needs. EDs have relatively limited resources available to address health-related social needs. We encourage research on the development of scalable solutions for identifying and addressing health-related social needs in the ED.

Increased Moraxella and Streptococcus species abundance after severe bronchiolitis is associated with recurrent wheezing.

BACKGROUND: The role of the airway microbiome in the development of recurrent wheezing and asthma remains uncertain, particularly in the high-risk group of infants hospitalized for bronchiolitis. OBJECTIVE: We sought to examine the relation of the nasal microbiota at bronchiolitis-related hospitalization and 3 later points to the risk of recurrent wheezing by age 3 years. METHODS: In 17 US centers researchers collected clinical data and nasal swabs from infants hospitalized for bronchiolitis. Trained parents collected nasal swabs 3 weeks after hospitalization and, when healthy, during the summer and 1 year after hospitalization. We applied 16S rRNA gene sequencing to all nasal swabs. We used joint modeling to examine the relation of longitudinal nasal microbiota abundances to the risk of recurrent wheezing. RESULTS: Among 842 infants hospitalized for bronchiolitis, there was 88% follow-up at 3 years, and 31% had recurrent wheezing. The median age at enrollment was 3.2 months (interquartile range, 1.7-5.8 months). In joint modeling analyses adjusting for 16 covariates, including viral cause, a 10% increase in relative abundance of Moraxella or Streptococcus species 3 weeks after day 1 of hospitalization was associated with an increased risk of recurrent wheezing (hazard ratio [HR] of 1.38 and 95% high-density interval [HDI] of 1.11-1.85 and HR of 1.76 and 95% HDI of 1.13-3.19, respectively). Increased Streptococcus species abundance the summer after hospitalization was also associated with a greater risk of recurrent wheezing (HR, 1.76; 95% HDI, 1.15-3.27). CONCLUSIONS: Enrichment of Moraxella or Streptococcus species after bronchiolitis hospitalization was associated with recurrent wheezing by age 3 years, possibly providing new avenues to ameliorate the long-term respiratory outcomes of infants with severe bronchiolitis.

National Study of the Emergency Physician Workforce, 2020.

STUDY OBJECTIVE: We describe the current US emergency physician workforce. METHODS: We analyzed the 2020 American Medical Association Physician Masterfile data set. All physicians who designated emergency medicine as their primary or secondary specialty were included; nonactive physicians, residents, primarily research or teaching faculty, or those primarily involved in administration or nonclinical work were excluded. We calculated emergency physician population density, using 2018 Census Bureau estimates of the US population; urban-rural assignments were based on Urban Influence Codes. We compared 2020 results with our previous analysis of the 2008 emergency physician workforce. Again, we were unable to account for American Osteopathic Board of Emergency Medicine certification. RESULTS: There were 48,835 clinically active emergency physicians in 2020. The median age was 50 years (interquartile range [IQR] 41 to 62 years) and 28% were women. Overall density of emergency physicians per 100,000 population was 14.9. Most emergency physicians were in urban areas (92%), whereas 2,730 (6%) were in large rural areas and 1,197 (2%) in small rural areas. Urban emergency physicians were younger (median age 50 years; IQR 41 to 61 years) than those in large rural areas (median age 58 years; IQR 47 to 67 years) or small rural areas (median age 62 years; IQR 51 to 68 years), and more likely to be women (29%, 20%, and 19%, respectively). Most emergency physicians in small rural areas (71%) completed their medical training more than 20 years ago. Compared with 2008, the total number of clinically active emergency physicians has increased by 9,774, but, per 100,000 US population in 2020, emergency physician density decreased in both large rural (-0.4) and small rural (-3.7) areas. CONCLUSION: Urban emergency physicians in 2020 remain substantially younger than rural emergency physicians, with many rural ones near the US retirement age. We did not observe a continued increase in the percentage of female physicians among emergency physicians. Given the ongoing demand for physicians in all US emergency departments, this analysis provides essential information for understanding the current emergency physician workforce and the challenges ahead.

Severe bronchiolitis profiles and risk of recurrent wheeze by age 3 years.

BACKGROUND: A better understanding of bronchiolitis heterogeneity might help clarify its relationship with the development of recurrent wheezing and asthma. OBJECTIVES: We sought to identify severe bronchiolitis profiles using a clustering approach and to investigate for the first time their association with allergy/inflammatory biomarkers, nasopharyngeal microbiota, and development of recurrent wheezing by age 3 years. METHODS: We analyzed data from a prospective, 17-center US cohort study of 921 infants (age <1 year) hospitalized with bronchiolitis (2011-2014 winters) with posthospitalization follow-up. Severe bronchiolitis profiles at baseline (hospitalization) were determined by using latent class analysis based on clinical factors and viral etiology. Blood biomarkers and nasopharyngeal microbiota profiles were determined by using samples collected within 24 hours of hospitalization. Recurrent wheezing by age 3 years was defined based on parental report of breathing problem episodes after discharge. RESULTS: Three severe bronchiolitis profiles were identified: profile A (15%), which was characterized by a history of breathing problems/eczema during infancy and non-respiratory syncytial virus (mostly rhinovirus) infection; profile B (49%), which has the largest probability of respiratory syncytial virus infection and resembled classic respiratory syncytial virus-induced bronchiolitis; and profile C (36%), which was composed of the most severely ill group. Profile A infants had higher eosinophil counts, higher cathelicidin levels, and increased proportions of Haemophilus-dominant or Moraxella-dominant microbiota profiles. Compared with profile B, we observed significantly increased risk of recurrent wheezing in children with profile A (hazard ratio, 2.64; 95% CI, 1.90-3.68) and, to a lesser extent, with profile C (hazard ratio, 1.51; 95% CI, 1.14-2.01). CONCLUSION: Although longer follow-up is needed, our results might help identify, among children hospitalized for bronchiolitis, subgroups with particularly increased risk of asthma.

Haemophilus-Dominant Nasopharyngeal Microbiota Is Associated With Delayed Clearance of Respiratory Syncytial Virus in Infants Hospitalized for Bronchiolitis.

The relation of nasopharyngeal microbiota to the clearance of respiratory syncytial virus (RSV) in infants hospitalized for bronchiolitis is not known. In a multicenter cohort, we found that 106 of 557 infants (19%) hospitalized with RSV bronchiolitis had the same RSV subtype 3 weeks later (ie, delayed clearance of RSV). Using 16S ribosomal RNA gene sequencing and a clustering approach, infants with a Haemophilus-dominant microbiota profile at hospitalization were more likely than those with a mixed profile to have delayed clearance, after adjustment for 11 factors, including viral load. Nasopharyngeal microbiota composition is associated with delayed RSV clearance.