An altered natural killer cell immunophenotype characterizes clinically severe pediatric RSV infection.

Respiratory syncytial virus (RSV) infects nearly all children by 2 years of age and is a leading cause of pediatric hospitalizations. A subset of children with RSV infection (RSV children) develop respiratory failure requiring intensive care, but immune mechanisms distinguishing severe pediatric RSV infection are not fully elucidated. Natural killer (NK) cells are key innate immune effectors of viral host defense.