Pediatric Hospitalizations Higher for RSV than Omicron or Influenza

Rates of hospitalization were higher for children with respiratory syncytial virus (RSV) than with Omicron or influenza, according to results from a retrospective cohort study published online ahead of print in JAMA Pediatrics.

“Our findings suggest that RSV infections more often require hospitalization and respiratory support, underscoring the importance of preventive measures, such as recently approved RSV vaccines,” wrote corresponding author Pontus Hedberg, MD, PhD, of Karolinska Institutet, Stockholm, Sweden, and coauthors in a research letter.

The study included 2596 children seen at three pediatric emergency departments between August 1, 2021, and September 15, 2022. Among them, 34.5% tested positive for Omicron (these cases were limited to the window when Omicron was the dominant SARS-CoV-2 variant), 16.4% tested positive for influenza A/B, and 48% tested positive for RSV. Children younger than 2 years made up 77.7% of patients with RSV, 72.3% of patients with Omicron, and 19% of patients with influenza.

Among all children in the study, hospitalization rates were 81.7% for RSV, 31.5% for Omicron, and 27.7% for influenza, researchers reported. “Hospitalization rates were higher in patients infected with RSV vs Omicron in all age groups,” they wrote, “but no differences were observed between influenza and Omicron.”

For infants aged 1 year and younger, odds ratios (ORs) for hospitalization were 11.29 for RSV vs Omicron and 1.67 for influenza vs Omicron, according to the study. For children 2 to 4 years, ORs for hospitalization were 3.96 for RSV vs Omicron and 0.31 for influenza vs Omicron. For patients 5 to 17 years, ORs for hospitalization were 5.22 for RSV vs Omicron and 1.10 for influenza vs Omicron.

Intensive care unit admission rates were 2.9% with RSV, compared with 0.9% with influenza and 0.7% with Omicron, the study found. Meanwhile, rates of 30-day all-cause mortality were 0.2% with Omicron and 0.1% with RSV.

Reference

Hedberg P, Abdel-Halim L, Valik JK, Alfvén T, Nauclér P. Outcomes of pediatric SARS-CoV-2 Omicron infection vs influenza and respiratory syncytial virus infections. JAMA Pediatr. Published online December 26, 2023. doi:10.1001/jamapediatrics.2023.5734