Most Infants in ICU Due to RSV Were Full-Term and Previously Healthy

Respiratory syncytial virus (RSV) causes significant morbidity in previously healthy full-term infants as well as those born prematurely or with underlying conditions, according to study findings published in JAMA Network Open.

Researchers evaluated the characteristics, clinical course, and outcomes of infants less than a year old who were admitted for intensive care at 39 US pediatric hospitals in 27 states between October 17 and December 16, 2022, which was the peak of the RSV season in the US.

Data were obtained from the RSV Pediatric Intensive Care (RSV-PIC) registry, which required admission to an intensive care unit or high acuity unit for at least 24 hours for RSV-related illness, symptom onset of less than 10 days before hospitalization, and evidence of laboratory-confirmed RSV before hospitalization or within 72 hours of admission.

The associations between intubation status and demographic factors, gestational age, and underlying conditions were assessed with mixed-effects multivariable log-binomial regression models to calculate prevalence ratios.

The RSV-PIC registry included 600 infants, of whom 559 (93.2%) were admitted within the first month of the study period. Participants’ median age was 2.6 (interquartile range [IQR], 1.4-6.0) months, 60% were male, 81% were previously healthy, 29% were born prematurely, and about one-quarter were intubated.

Lower respiratory tract infections (LRTIs) were the primary reason for admission (99%), although infants who were intubated had an increased frequency of apnea or bradycardia (13%) and were more frequently younger than 3 months old.

Oxygen support was required in 572 infants (95.3%) at admission, and 143 infants (24%) received invasive mechanical ventilation (median, 6.0 [IQR, 4.0-10] days). Of the infants who were intubated, 101 (70.6%) were younger than 3 months old. High-flow nasal cannula was the highest level of respiratory support for nonintubated infants (40.5%), followed by bilevel positive airway pressure (25.0%) and continuous positive airway pressure (8.7%). The median hospitalization length for surviving infants was 5 (IQR, 4-10) days. Extracorporeal membrane oxygenation was needed in 4 infants, and 2 infants died.

The risk for intubation was highest among infants younger than 3 months old vs those aged 6 to 11 months, those who were born prematurely (<37 weeks), and those who had public rather than private insurance, after adjustment.

Among several limitations, the study population included only the first 15 to 20 consecutive RSV cases at each hospital, and the inclusion of only clinician-ordered, laboratory-confirmed RSV cases may have resulted in missing cases. Also, although most infants were tested for influenza and SARS-CoV-2, only half of infants were tested via a respiratory viral panel. Furthermore, the study period did not include the RSV peak in some states, and the trial was biased toward infants with the most severe RSV infections.

“In this cross-sectional study, most US infants who required intensive care for RSV LRTIs were young, healthy, and born at term,” the study authors concluded, adding that “These findings support the use of new preventative interventions, including long-lasting monoclonal antibodies in all infants and maternal vaccination.”

Disclosure: Some of the study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

This article originally appeared on Pulmonology Advisor