Resurgence Alert: Pediatric RSV Infections Spike Post-Pandemic 

Resurgence Alert: Pediatric RSV Infections Spike Post-Pandemic. Credit | Shutterstock

United States: Health experts are highly stressed as the number of cases linked to respiratory syncytial virus (RSV) among pediatrics has increased between 2017 and 2023. The conclusion was drawn in a newly published JAMA Network Open, which explored demographics, clinical outcomes, and respiratory support. 

RSV remains the primary cause of pediatric hospitalizations due to respiratory complications such as bronchiolitis, pneumonia, and apnea. Prior to the COVID-19 pandemic, more than two million children under the age of five in the United States required medical attention for RSV. However, pediatric hospitalizations for RSV markedly decreased during the pandemic but saw a resurgence in 2022. Emerging reports indicate a shift in the demographic profile of pediatric RSV cases due to reduced early-life exposure and altered seasonal patterns of the virus during the pandemic, as reported by news-medical.net. 

About the Study 

In this particular investigation, researchers compared the clinical outcomes of children under five years old infected with RSV before and after the COVID-19 pandemic. The study included patients from 48 children’s hospitals participating in the US Pediatric Health Information System (PHIS). Patients diagnosed with RSV between July 2017 and June 2023 were identified from the PHIS database. Demographic variables such as age, gender, child opportunity index score, and race/ethnicity were documented. 

Resurgence Alert: Pediatric RSV Infections Spike Post-Pandemic. Credit | Credit: Getty Images
Resurgence Alert: Pediatric RSV Infections Spike Post-Pandemic. Credit | Credit: Getty Images

Clinical characteristics encompassed hospital admissions, levels of care (emergency, inpatient, intensive care), and complex chronic conditions. Outcomes studied included length of hospital stay (LOS), types of respiratory support used (such as a high-flow nasal cannula, invasive mechanical ventilation, non-invasive ventilation, high-frequency ventilation), and interventions like extracorporeal membrane oxygenation (ECMO), cardiopulmonary resuscitation (CPR), and inhaled nitric oxide (iNO). 

The RSV season was defined from July 1st to June 30th. The pre-pandemic period encompassed the 2017-18, 2018-19, and 2019-20 RSV seasons, while the post-pandemic period was designated as 2022-23. Statistical analyses utilized methods including the Cochran-Armitage or Pearson chi-squared tests for categorical variables and the Kruskal-Wallis test for continuous variables. Differences between pre-pandemic and post-pandemic RSV seasons were assessed using the Wilcoxon rank sum test. Estimates were made for total hospital days, intensive care unit (ICU) days, and days on respiratory support, as per the reports by news-medical.net.  

Key Findings 

In total, 288,816 pediatric patients were admitted to children’s hospitals due to RSV during the study period. The median age of patients was 8.9 months, with 55.2% being male and 42.2% identified as non-Hispanic White. There was a substantial decline in RSV infections early in the pandemic, with an 82% reduction in hospital admissions during the 2020-21 period compared to pre-pandemic levels. 

However, RSV infections saw a significant resurgence in 2022-23 compared to pre-pandemic seasons. During the post-pandemic seasons, hospitalizations and ICU admissions due to RSV increased by 86.7% and 43.5%, respectively. Moreover, the cumulative number of hospital and ICU days was notably higher in 2022-23 compared to the seasonal average before the pandemic. 

Resurgence Alert: Pediatric RSV Infections Spike Post-Pandemic. Credit | Shutterstock
Resurgence Alert: Pediatric RSV Infections Spike Post-Pandemic. Credit | Shutterstock

Children infected with RSV and those hospitalized for the virus in the post-pandemic period were generally older compared to those in pre-pandemic seasons. Throughout all seasons, hospitalized patients tended to be younger than those discharged from the emergency department (ED). Notably, while a greater proportion of patients required hospitalization or ICU care during the post-pandemic period, the percentage of hospitalized patients relative to overall RSV cases was lower in 2022-23 compared to pre-pandemic seasons. 

Similarly, fewer hospitalized patients required ICU care in 2022-23 compared to pre-pandemic seasons. LOS in hospitals or ICUs was also shorter post-pandemic compared to pre-pandemic periods. Although the total number of deaths increased in 2022-23 compared to pre-pandemic seasons, the mortality rate among hospitalized patients actually decreased. Nevertheless, mortality rates were higher in 2022-23 relative to pre-pandemic seasons. There was no significant difference in mortality rates among patients admitted to the ICU between pre- and post-pandemic seasons, as per news-medical.net.  

A lower percentage of ICU patients required CPR in 2022-23 compared to pre-pandemic seasons. Overall, advanced respiratory support was necessary for 21.6% of hospitalized patients. The need for advanced respiratory support was 70% higher in 2022-23 compared to before the pandemic. The use of non-invasive ventilation and invasive mechanical ventilation increased by over 47% and 28%, respectively, in 2022-23 compared to pre-pandemic seasons. Notably, the use of high-flow nasal cannula nearly doubled in 2022-23 compared to pre-pandemic levels. 

However, the proportion of patients requiring high-flow nasal cannula was similar between pre- (14.5%) and post-pandemic (14.2%) seasons. ECMO usage did not differ significantly between seasons, while the use of inhaled nitric oxide was notably reduced in 2022-23. Across seasons, children requiring invasive mechanical ventilation tended to be younger than those needing non-invasive ventilation or high-flow nasal cannula. The prevalence of comorbidities was higher among patients requiring more invasive forms of respiratory support. 

Conclusions 

The findings align with national and regional data indicating a sharp decline in pediatric RSV infections during the COVID-19 pandemic, followed by a resurgence post-pandemic. The resurgence led to more than a threefold increase in ED visits compared to pre-pandemic seasons. Despite a lower proportion of patients requiring hospitalization or ICU care in 2022-23 compared to typical RSV seasons, the strain on hospital resources was 50% greater post-pandemic. 

It is important to note that the study’s population may not fully represent the entire pediatric demographic in the US, as it only included 48 hospitals. Coinfections were acknowledged to potentially impact the severity of RSV cases, though data on this aspect were not available. Furthermore, data on high-flow nasal cannula usage were limited to 33 hospitals. Together, the study underscores a resurgence in pediatric RSV infections post-pandemic, accompanied by significant increases in ED visits, cumulative hospital or ICU days, and requirements for advanced respiratory support.