Human Metapneumovirus Versus Respiratory Syncytial Virus in the Pediatric Emergency Department: Inflammatory Indices, Cycle-Threshold Profiles and Outcomes.

Compared with RSV, hMPV affected older children with higher comorbidity, more pneumonia and neutrophil-driven inflammation (neutrophil-to-lymphocyte ratio [NLR], systemic immune-inflammation index [SII], c-reactive protein higher; p ≤ 0.006).

Dominant Ct differed across pathogens (Kruskal-Wallis p < 0.001); rhinovirus carried the lowest viral load.

Paired non-dominant Ct exceeded dominant Ct (median ΔCt +3.6, p = 0.013).

Per-target Ct supports the lowest-Ct-dominant convention.