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Heightened neurologic complications in children with pandemic H1N1 influenza

Jeffrey J Ekstrand1, Amy Herbener, Julia Rawlings

  • 1Division of Pediatric Neurology, University of Utah School of Medicine, Salt Lake City, UT 84108, USA.

Annals of Neurology
|September 25, 2010
PubMed

Insights

The 2009 pandemic influenza A (H1N1) virus caused more severe neurological complications, such as encephalopathy and seizures, in children compared to seasonal flu. These effects, including persistent focal neurological symptoms, were more pronounced during the second wave.

Area of Science:

  • Neurology
  • Infectious Diseases
  • Pediatrics

Background:

  • The 2009 pandemic influenza A (H1N1) virus is known to cause neurological complications.
  • Neurological manifestations can include seizures and encephalopathy.

Purpose of the Study:

  • To identify and characterize neurological complications in children infected with the 2009 H1N1 influenza.
  • To compare the neurological impact of pandemic 2009 H1N1 influenza with seasonal influenza.

Main Methods:

  • Retrospective identification of 18 pediatric patients with 2009 H1N1 influenza and neurological complications.
  • Comparison of clinical characteristics and outcomes between pandemic H1N1 and seasonal influenza cases.

Main Results:

  • Seizures, encephalopathy, and status epilepticus were frequent presentations in H1N1 patients.
  • 22% of patients had persistent focal neurological symptoms at discharge.
  • Pandemic 2009 H1N1 influenza was associated with higher rates of encephalopathy, focal neurological findings, aphasia, and abnormal EEG compared to seasonal influenza.
  • A trend towards increased neurological complications was observed with the second wave of influenza activity.

Conclusions:

  • Pandemic 2009 H1N1 influenza poses a significant risk for severe neurological complications in children.
  • Neurological sequelae can be long-lasting, impacting patient recovery.
  • Further research is warranted to understand the mechanisms and long-term effects of H1N1-associated neurological disease.

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