Is Fever a Red Flag for Bacterial Pneumonia in Children With Viral Bronchiolitis?

We hypothesized that fever in children with viral bronchiolitis indicates the need for consideration of superimposed bacterial pneumonia. We conducted a retrospective study of 349 children aged 2 years and younger with diagnoses of respiratory syncytial virus (RSV) and viral upper respiratory infection. Data were analyzed using Pearson χ² test. One hundred seventy-eight children had RSV with no other identified virus. The majority of children (56%) who had only RSV were afebrile. Febrile children with RSV were over twice as likely to be diagnosed with bacterial pneumonia as those who were afebrile (60% vs 27%, P < .001). In the 171 children who had bronchiolitis caused by a virus other than RSV, 51% were afebrile. These children were 8 times more likely to be diagnosed with pneumonia than those who were afebrile (65% vs 8%, P < .001). Evaluation of febrile children with viral bronchiolitis may allow early diagnosis and treatment of secondary bacterial pneumonia.