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Published on: December 11, 2013
Viral Detection in Children <5 Years with Bronchiolitis, Pneumonia, and Croup, New Vaccine Surveillance Network,
Zheyi Teoh1,2, Ariana P Toepfer3, Chelsea Rohlfs4
1Seattle Children's Research Institute, Seattle, WA, United States.
Insights
Respiratory syncytial virus (RSV) and rhinoviruses/enteroviruses (RV/EV) were common in pediatric acute respiratory illnesses. Viral detection proportions remained similar before and after COVID-19, with notable exceptions for parainfluenza virus (PIV).
Area of Science:
- Pediatric infectious diseases
- Virology
- Public health
Background:
- Bronchiolitis, pneumonia, and croup represent a significant cause of pediatric hospitalizations globally.
- Evaluating viral etiologies of these acute respiratory illness (ARI) syndromes is crucial for understanding disease burden and informing public health strategies.
- The COVID-19 pandemic has potentially altered the epidemiology of common respiratory viruses.
Purpose of the Study:
- To conduct an updated, multi-center, multi-pathogen analysis of viral detections in children under 5 with ARI syndromes.
- To compare viral patterns before (2017-2019) and after (2021-2023) the emergence of SARS-CoV-2.
- To identify specific viruses associated with bronchiolitis, pneumonia, and croup, considering age and underlying medical conditions.
Main Methods:
- Retrospective cohort study including children under 5 diagnosed with bronchiolitis, pneumonia, or croup from 2017-2023.
- Respiratory virus detection using research and clinical respiratory swabs.
- Data collection included demographic and clinical information from caregiver interviews and chart reviews, with analysis stratified by age, surveillance year, and medical conditions.
Main Results:
- Over 80% of the 14,340 bronchiolitis, 4,423 pneumonia, and 2,367 croup cases had at least one respiratory virus detected.
- Respiratory syncytial virus (RSV) was most frequent in bronchiolitis (41%) and pneumonia (26%).
- Parainfluenza virus (PIV) detections decreased post-COVID-19, while SARS-CoV-2 emerged in croup cases (7.6%). Rhinoviruses/enteroviruses (RV/EV) were the second most common virus overall, particularly in infants and those with underlying conditions.
Conclusions:
- A high proportion of viral detections were observed in young children with common ARI syndromes, with RSV, RV/EV, and PIV being particularly prevalent.
- Viral patterns for most pathogens remained consistent pre- and post-COVID-19, with notable decreases in PIV and influenza virus detections.
- RV/EV demonstrated significant detection rates in specific age groups and among children with underlying medical conditions, highlighting their importance in pediatric respiratory illnesses.
Introduction:
Bronchiolitis, pneumonia, and croup account for a substantial burden of pediatric hospitalizations. We aim to provide an updated, multi-center, multi-pathogen evaluation of viral detections seen with these acute respiratory illness (ARI) syndromes before and after the COVID-19 pandemic.
Methods:
We included children <5 years with a diagnosis of bronchiolitis, pneumonia, or croup during 2017-2023 from the New Vaccine Surveillance Network. Respiratory viruses were detected with a research ± clinical respiratory swabs; demographic and clinical data were obtained from caregiver interview and chart review. Virus-specific proportions across all three ARI syndromes were described, including comparisons stratified by age, surveillance year including pre- (2017-2019) and post (2021-2023) COVID-19 onset periods, and underlying medical condition.
Results:
Among 14 340 cases of bronchiolitis, 4423 cases of pneumonia, and 2367 cases of croup, >80% had one or more respiratory virus detected. Respiratory syncytial virus (RSV) was the most frequent virus detected in bronchiolitis (41%) and pneumonia (26%), with a similar distribution across the COVID-19 onset periods. Parainfluenza virus (PIV) was the most frequent virus detected in croup (28%), but detections fell in the post-COVID-19 onset period by 8.4%; there was a comparable proportion of SARS-CoV-2 detections (7.6%) that emerged among croup cases. Rhinoviruses/enteroviruses (RV/EV) were the second most frequently detected virus across all three ARI syndromes and were the predominant virus in children <6 months and children with an underlying medical condition diagnosed with croup. Codetections were present in 17%-19% of bronchiolitis, pneumonia, and croup cases.
Discussion:
We found a high proportion of respiratory viral detections in children <5 years with bronchiolitis, pneumonia, or croup, particularly with RSV, RV/EV, and PIV. Most viruses were identified in similar proportions before and after the emergence of SARS-CoV-2, except for PIV and influenza virus. In our cohort, there was a high proportion of viral detection across all three ARI syndromes, with RV/EV frequently detected in certain age groups and among children with underlying conditions.
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