J Korean Med Sci.  2012 Mar;27(3):332-334. 10.3346/jkms.2012.27.3.332.

Positive Rates of 2009 Novel Influenza A (H1N1) was High in School-Aged Individuals: Significance in Pandemic Control

• Kang SH
• Choi HM
• Lee EH

• KMID: 1793009
• DOI: http://doi.org/10.3346/jkms.2012.27.3.332

Abstract

In this study, data from a pandemic H1N1 outbreak in Korea were analyzed according to time, geography (districts), and age. A total of 252,271 samples collected nationwide were referred to the Greencross Reference Laboratory from June 2009 to February 2010 for H1N1 confirmation testing. Of these samples, 105,300 (41.7%) were H1N1-positive. With time, positivity was highest (57.0%) from October 26 - November 1 (4 weeks after Chuseok). The positive rates among districts show the highest value in Ulsan City (63.1%) and the lowest in Gyeongnam Province (32.8%). The positive rates for ages 0-2, 3-5, 6-11, 12-17, 18-20, 21-30, 31-40, 41-50, 51-60, and > 60 yr were 17.0%, 33.1%, 56.2%, 55.5%, 55.3%, 41.5%, 28.2%, 30.5%, 31.1%, and 16.8%, respectively, indirectly indicating propagation of H1N1 through schools. Pandemic control should involve school-targeted strategies.

Keyword

Influenza A Virus, H1N1 Subtype; Positive Rates; Korea

MeSH Terms

Adolescent
Adult
Aged
Child
Child, Preschool
Female
Humans
Infant
Infant, Newborn
*Influenza A Virus, H1N1 Subtype
Influenza, Human/*epidemiology/prevention & control
Male
Middle Aged
*Pandemics/prevention & control/statistics & numerical data
Republic of Korea/epidemiology
Students
Young Adult

Figure

• 

  Fig. 1 Numbers of total referred cases and positive cases for H1N1 by real-time RT-PCR during 2009 novel influenza epidemic as observed weekly interval.

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