The Centers for Disease Control and Prevention (CDC) has released a comprehensive report, revealing that Influenza-Associated Encephalopathy (IAE), a severe neurological complication of influenza, had a significant impact on the pediatric population during the high-severity 2024-25 flu season. IAE, although rare, can rapidly lead to an intense neurologic deterioration leading to fatal outcomes. Among the IAE cases reported, acute necrotizing encephalopathy (ANE), a highly severe form of IAE with poor prognosis, constituted a substantial portion. The report emphasized the importance of proactive healthcare practices such as annual influenza vaccinations, especially for children aged 6 months and above. This course of action could potentially mitigate severe complications like IAE.
During the 2024-25 influenza season, it was reported that 109 U.S pediatric IAE cases were identified, with 55% of affected children being previously healthy. Notably, ANE made up 37 of the IAE cases reported. Alarming statistics show that 74% of IAE patients required admission to an intensive care unit, and 19% succumbed to the illness. Mortality among ANE patients was even higher at a troubling 41%.
It’s worth noting that the 2024-25 influenza season was historically severe, with the highest number of pediatric influenza-associated deaths reported during a seasonal influenza epidemic since U.S. surveillance for these deaths commenced in 2004. Amid these exceptional circumstances, the CDC launched an appeal for cases of IAE to better characterize these syndromes in the U.S population.
Healthcare professionals treating children with an altered level of consciousness and recent or current febrile illness when influenza viruses are circulating are urged to consider the diagnosis of IAE, especially when neurologic disease is suspected. The data reported on this public health investigation permits a clearer understanding of the nature of these remaining influenza-associated neurologic diseases, allowing healthcare professionals to better protect the lives of their patients.