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Hospitalizations associated with pandemic influenza A (H1N1) 2009 in asthmatic children in Japan

Toshio Katsunuma1, Takehiko Matsui, Tsutomu Iwata

  • 1Department of Pediatrics, Jikei University Daisan Hospital, Komae City, Tokyo, Japan. tkatsunuma@jikei.ac.jp

Allergology International : Official Journal of the Japanese Society of Allergology
|October 22, 2011
PubMed

Insights

Asthma did not increase the risk of severe pandemic influenza A (H1N1) 2009 infection in children. This study found no significant differences in intensive care or ventilation needs between asthmatic and non-asthmatic children.

Area of Science:

  • Pediatric Allergy and Immunology
  • Infectious Diseases
  • Epidemiology

Background:

  • The 2009 pandemic influenza A (H1N1) caused a significant epidemic in Japan.
  • Early suggestions indicated asthma as a potential risk factor for severe H1N1 infection.
  • The Japanese Society of Pediatric Allergy and Clinical Immunology (JSPACI) investigated this potential link in children.

Purpose of the Study:

  • To investigate whether asthma is a risk factor for severe pandemic influenza A (H1N1) 2009 infection in children.
  • To compare clinical outcomes of H1N1 infection in asthmatic versus non-asthmatic pediatric patients.

Main Methods:

  • A nationwide appeal was made by JSPACI for clinical data on hospitalized children (0-19 years) with H1N1 infection.
  • Data from 333 asthmatic and 388 non-asthmatic children across 61 medical centers were analyzed.
  • Clinical information including respiratory symptoms, ICU admission, and mechanical ventilation was collected.

Main Results:

  • Significantly more asthmatic children were admitted for respiratory symptoms compared to non-asthmatic children (p < 0.001).
  • No significant differences were observed in ICU admission rates or the need for mechanical ventilation between the two groups.
  • Antiviral medications were administered within 24 hours to approximately 85% of patients in both groups.

Conclusions:

  • Asthma does not appear to be a significant risk factor for severe pandemic influenza A (H1N1) 2009 infection in children.
  • While asthmatic children presented more with respiratory symptoms, their severe outcomes were comparable to non-asthmatic children.
Abstract

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