J Korean Med Sci.  2012 Apr;27(4):408-415. 10.3346/jkms.2012.27.4.408.

Characteristics of Hospitalized Children with 2009 Pandemic Influenza A (H1N1): A Multicenter Study in Korea

• Ko JH
• Kim JH
• Kang JH
• Kim JH
• Eun BW
• Kim KH
• Hong JY
• Oh SH

• KMID: 2157902
• DOI: http://doi.org/10.3346/jkms.2012.27.4.408

Abstract

The majority of Korean patients with pandemic influenza A (H1N1) during the 2009 epidemic were under 20 yr of age. The limited data on the clinical characteristics of these children led us to conduct a case note-based investigation of children admitted to 6 university hospitals with 2009 H1N1 influenza. A total of 804 children was enrolled. The median age was 5 yr; 63.8% were males; and 22.4% had at least one chronic underlying disease. Ninety-five of the patients (11.8%) were critically ill and they suffered more from shortness of breath, dyspnea and lymphopenia than the other patients. Among all the patients, 98.8% were treated with antivirals and 73% received treatment within 48 hr of illness onset. All the enrolled patients are alive and appear to have had good outcomes, probably due to the early intervention and antiviral treatment. This study deals with hospitalized children whose diagnoses of influenza A (H1N1) were confirmed, and therefore provides important new information about the clinical patterns of children with influenza A (H1N1) in Korea.

Keyword

Pandemic Influenza A (H1N1); Children; Korea; Epidemiology; Clinical Characteristics

MeSH Terms

Adolescent
Antiviral Agents/therapeutic use
Child
Child, Hospitalized
Child, Preschool
Critical Illness
Dyspnea/etiology
Female
Humans
Infant
Infant, Newborn
Influenza A Virus, H1N1 Subtype/genetics/*isolation & purification
Influenza, Human/*diagnosis/drug therapy/epidemiology
Lymphopenia/etiology
Male
Oseltamivir/therapeutic use
Pandemics
Republic of Korea/epidemiology
Retrospective Studies

Figure

• 

  Fig. 1 Weekly distribution of children hospitalized with influenza A (H1N1) in 6 university hospitals from August 2009 to January 2010 in Korea. The first day of 34th week of year 2009 is August 16, 2009, and the first study patient developed the illness on August 20, 2009.

• 

  Fig. 2 Age and sex distribution of hospitalized children.

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