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Review
. 2025 Jun 1;14(6):551.
doi: 10.3390/pathogens14060551.

Influenza-Related Encephalopathy in Children: Epidemiology and Literature Review from a Tertiary Hospital in Northern Italy (Winter 2023-2024)

Raffaele Vitale  1 , Marco Denina  1 , Laura Badiali  2 , Matteo Sandei  2 , Giulia Mazzetti  2 , Carlotta Canavese  3 , Aba Tocchet  3 , Antonia Versace  4 , Silvia Garazzino  1   2
Affiliations
Review

Influenza-Related Encephalopathy in Children: Epidemiology and Literature Review from a Tertiary Hospital in Northern Italy (Winter 2023-2024)

Raffaele Vitale et al. Pathogens. .

Abstract

Introduction: While influenza-associated encephalopathy (IAE) in children remains a serious concern, recent evidence suggests a shift in its epidemiology, with a possible decline in incidence and severity over time.

Methods: This retrospective review includes patients aged 0-18 admitted to a tertiary hospital in Northern Italy between November 2023 and February 2025. Inclusion criteria were a positive influenza test, influenza-like symptoms, and neurological involvement. Findings are interpreted alongside current literature.

Results: Twenty-five unvaccinated children met criteria for IAE (11 in 2023/24; 14 in 2024/25). Neurological comorbidities were present in 40%. All patients had pathological EEGs. Lumbar puncture was performed in 40%, with abnormalities in 33%. Brain imaging was conducted in 56% of cases, revealing findings in 15%. All received oseltamivir; 60% were also treated with dexamethasone. Severe complications occurred in 16%, while 12% had persistent symptoms or required therapy at discharge. After adjusting for seasonal peak timing, no significant inter-seasonal difference was observed.

Discussion: Although IAE continues to present serious risks, recent trends suggest a changing burden. The lack of vaccination among cases underscores the need for prevention. Study limitations include its single-center design and the absence of long-term follow-up. Broader prospective studies are needed.

Keywords: children; encephalitis; encephalopathy; influenza; necrotizing encephalitis.

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Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
Diagram of remarkable population features.
Figure 2
Figure 2
Cumulative incidence curves of influenza-related encephalopathy in two winters. To the left: uncorrected curve; to the right: curves corrected for peak-to-peak difference in incidence.
See this image and copyright information in PMC

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