Invasive bacterial infection in febrile neonates with influenza infection

Abstract

Introduction

Febrile infants with a confirmed viral infection are at lower risk of an invasive bacterial infection (IBI). Several authors recommend individualizing screening in febrile infants aged 1 to 3 months, but there are currently no specific recommendations for neonates. The objective of our study was to determine the prevalence of IBI in febrile neonates with influenzavirus infection.

Methods

Observational descriptive study in febrile infants aged less than 29 days managed in the emergency department with a microbiological diagnosis of influenza over a 21-year period (2004–2023). We excluded patients with an abnormal pediatric assessment triangle or who had received antibiotherapy in the past week.

Results

The sample included 112 patients. Urine culture was performed in all, blood culture in 108 (96.4%) and lumbar puncture in 61 (54.5%). A total of 102 (91.1%) were admitted to hospital, of who 61 (59.8%) received antibiotics. An IBI was identified in one patient (prevalence 0.9%; 95% CI, 0.2%–4.9%): a female aged 8 days with a bloodstream infection by Escherichia coli. Additionally, 7 (6.3%, 95% CI: 3.1%–12.3%) patients presented with a urinary tract infection.

Conclusions

The prevalence of IBI in febrile neonates with influenza infection is very low, with no detection of cases of bacterial meningitis. Confirmation of these results in a multicenter study, which could also identify associated risk factors, would allow a less aggressive approach of low-risk patients.