Broad spectrum of Pediatric Influenza-Associated Disease
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Over a decade of population-based surveillance through teh Influenza Hospitalization Surveillance Network (FluSurv-NET) shows that although influenza is widely recognized as a respiratory virus, a ample proportion of hospitalized children experience serious non-respiratory complications.
The findings, which researchers presented at IDWeek 2025 (October 19 to October 22, Atlanta, Georgia) demonstrate that influenza’s burden in pediatric populations extends far beyond the lungs and warrants greater clinical attention, especially among pharmacists and inpatient care teams who help guide antiviral therapy, supportive care, and vaccine uptake.
!A medical worker is giving a Covid-19 vaccination to a young girl in a clinic indoors. both are wearing face masks for safety during the antiviral immunization. | Image Credit: Prostock-studio | adobe.stock.com
Image Credit: Prostock-studio | adobe.stock.com
An extensive cohort study spanning 2010-2011 to 2022-2023 found that 17,442 children under 18 years were hospitalized with laboratory-confirmed influenza, and 16,233 had at least 1 acute International Classification of Diseases (ICD)-coded diagnosis.Most of these (15,800) had a respiratory diagnosis; however, 4,469 had at least 1 non-respiratory diagnosis, and 433 had only non-respiratory diagnoses. The non-respiratory complication categories, most frequently, were orbit/ear/mastoid disorders, neurologic complications, hematologic complications, sepsis, and gastrointestinal complications.
These findings reinforce that influenza can manifest as a multi-organ disease in hospitalized children, particularly in the post-2009 H1N1 era when pediatric complications became more widely tracked.
Children with Non-respiratory Presentations Differ Clinically
children who had only non-respiratory diagnoses were substantially different from those with respiratory involvement. They were older (median 5.1 vs 2.6 years; P* <.0001), were more often infected with influenza B (32% vs 23%; *P <.0001), and had a higher probability of being medically conditioned (59% vs 53%; P* =.015). Although children from the non-respiratory-only group had a higher risk profile, they were less likely to be admitted to the intensive care unit (ICU) (14% vs 23%; *P =.003).
Flu Can Be Severe Beyond respiratory Symptoms: Implications for Pharmacists & Pediatric Care
Influenza, commonly known as the flu, is often perceived as a respiratory illness. However, a recent extensive study presented at IDWeek 2025 highlights the significant risk of non-respiratory complications in hospitalized children with influenza, some leading to high rates of illness and even death. This underscores the importance of recognizing the flu’s potential severity beyond typical respiratory symptoms and emphasizes the crucial role pharmacists and healthcare teams play in prevention and treatment.
The research, involving a large cohort of children, revealed a substantial number develop non-respiratory complications during hospitalization for influenza. One particularly severe example is acute necrotizing encephalopathy (ANE), demonstrating the flu’s potential to cause serious neurological damage. [1]
Key Findings from the Study:
* Children presenting with non-respiratory symptoms were generally older and more likely to have underlying medical conditions.
* Influenza B virus was more frequently identified in cases with non-respiratory presentations.
* A concerning trend was observed: children with non-respiratory symptoms were less likely to receive antiviral treatment. [1]
These findings align with previous research demonstrating the potential for severe complications during influenza outbreaks. For example, a 2010 study in The New England Journal of Medicine detailed pediatric hospitalizations associated with the 2009 H1N1 pandemic, highlighting the severity of illness in children. [2] More recently, data from the CDC’s Morbidity and Mortality Weekly Report (MMWR) for the 2024-25 influenza season continues to document influenza-associated pediatric deaths, reinforcing the need for vigilance.[3]
Clinical Implications for Pharmacists and Healthcare Teams
pharmacists are uniquely positioned to minimize the impact of influenza. A cornerstone of prevention is universal influenza immunization, recommended for all individuals aged 6 months and older. Recent declines in pediatric influenza vaccination coverage are a cause for concern, particularly given the documented risk of non-respiratory complications. Pharmacists can play a vital role in advocating for vaccination, especially for children with pre-existing health conditions.
Moreover, the study emphasizes the need to reconsider antiviral use in children. Early empiric antiviral therapy should be considered for all hospitalized children suspected of having influenza, nonetheless of their presenting symptoms. Evidence from past pandemic research supports initiating antiviral treatment promptly to prevent severe complications, particularly in high-risk pediatric patients. [2]
Pharmacist actions:
* Promote Vaccination: Actively encourage influenza vaccination for all eligible individuals, emphasizing the importance for children and those with underlying conditions.
* Educate Parents & Caregivers: Inform families about the potential for non-respiratory complications and the importance of seeking prompt medical attention for concerning symptoms.
* Advocate for Early Antiviral Treatment: Collaborate with physicians to ensure timely consideration of antiviral therapy for hospitalized children with suspected influenza.
Conclusion
This large-scale, multi-season study confirms that influenza can lead to significant non-respiratory complications in children, with possibly devastating consequences. Recognizing these diverse manifestations, coupled with maximizing vaccination rates and initiating antiviral therapy without delay, are crucial strategies for improving outcomes in pediatric influenza cases.A proactive and informed approach by pharmacists and healthcare teams is essential to protect children from the full spectrum of influenza’s potential severity.
REFERENCES
- Kamidani S, Witt LS, Patterson A, et al. Respiratory and Nonrespiratory Complications in Children Hospitalized with Influenza in the Post-2009 H1N1 Pandemic Era. Presented at: IDWeek 2025; October 21,2025; Atlanta,GA. Accessed November 3, 2025, via IDWeek’s online conference platform. https://www.idweek.org/
- Libster R, Bugna J, Coviello S, et al.Pediatric hospitalizations associated with 2009 pandemic influenza A (H1N1) in Argentina. The New England Journal of Medicine.2010;362(1):45-55.https://www.nejm.org/doi/full/10.1056/NEJMoa0907673
- Reinhart K, Huang S, Kniss K, Reed C, Budd A. Influenza-Associated Pediatric Deaths – United States, 2024-25 Influenza Season. MMWR Morbidity and mortality Weekly Report. 2025;74(36):565-569. [https://www.cdc.gov/mmwr/volumes/74/wr/mm7436a2.htm](https://www.cdc.