Incidence and epidemiological characteristics of 2009 pandemic influenza A (H1N1) among school-based populations in Korea

Hyun Jung Kim, Byung-Chul Chun, Hoo Jae Hann, Jang Wook Sohn, Sae Yoon Kee, Si Hyun Kim, Myoung Youn Jo, Kyung Young Lee, Seok Hyeon Lee, Ja Kim Min, Hyeong Sik Ahn

Research output: Contribution to journalArticle

Abstract

Background: During the 2009 influenza pandemic in Korea, school-age children were mostly attacked by the novel influenza A virus (H1N1). Nevertheless, there is limited information on the cumulative incidence of the 2009 influenza pandemic among school populations. The aim of this study was to estimate the incidence of 2009 H1N1 influenza and influenza-like illness (ILI), and characterize the epidemiology among school-based populations in Korea. Materials and Methods: This study analyzed the data collected by the daily school influenza reporting system for laboratory-confirmed influenza (H1N1 2009 pdm) and ILI in elementary, middle and high schools in Korea during the period, July 1 to December 20, 2009. Results: Between July 1 and December 20, 2009, a total of 525,668 cases of H1N1 2009 pdm were reported from the schools analyzed. The cumulative incidence of H1N1 2009 pdm was highest in elementary school children between 8 and 13 years of age (11,058 per 100,000 population), followed by middle school students between 14 and 16 years of age (10,080 per 100,000), and high school students between 17 and 19 years of age (8,886 per 100,000). With the alignment of the epidemic curves by the three levels of school education, the age group-specific differences in the timing of the infection became apparent. The infections peaked 1 week earlier in both middle and high school students (November 3, 2009) than in elementary school children (November 10, 2009). The infections occurred an average of 7.3 [95% confidence interval(CI): 7.2-7.4] and 3.4 (95% CI: 3.3-3.5) days earlier in the middle and high school students, respectively, than elementary school children (P<0.001). The overall trend of the epidemic waves from the school reporting system data was similar to that of the national surveillance date from the Korea Centers for Disease Control and Prevention. Conclusions: This study suggests that during the 2009 pandemic, one student in every 10 was infected with H1N1 2009 pdm, which is double that estimated from the national surveillance data. In addition, middle and high school students were important drivers of H1N1 2009 pdm transmission in 2009. During the 2009 influenza pandemic, the daily school reporting system provided valuable information for estimating the incidence as well as the epidemiological characteristics in school-based populations.

Original languageEnglish
Pages (from-to)431-438
Number of pages8
JournalInfection and Chemotherapy
Volume44
Issue number6
DOIs
Publication statusPublished - 2012 Dec 1

Fingerprint

Pandemics
Korea
Human Influenza
Incidence
Population
Students
Infection
Confidence Intervals
Influenza A virus
Centers for Disease Control and Prevention (U.S.)
Information Systems

Keywords

  • H1N1
  • Incidence
  • Influenza
  • Pandemic
  • School

ASJC Scopus subject areas

  • Infectious Diseases
  • Pharmacology (medical)

Cite this

Incidence and epidemiological characteristics of 2009 pandemic influenza A (H1N1) among school-based populations in Korea. / Kim, Hyun Jung; Chun, Byung-Chul; Hann, Hoo Jae; Sohn, Jang Wook; Kee, Sae Yoon; Kim, Si Hyun; Jo, Myoung Youn; Lee, Kyung Young; Lee, Seok Hyeon; Min, Ja Kim; Ahn, Hyeong Sik.

In: Infection and Chemotherapy, Vol. 44, No. 6, 01.12.2012, p. 431-438.

Research output: Contribution to journalArticle

Kim, Hyun Jung ; Chun, Byung-Chul ; Hann, Hoo Jae ; Sohn, Jang Wook ; Kee, Sae Yoon ; Kim, Si Hyun ; Jo, Myoung Youn ; Lee, Kyung Young ; Lee, Seok Hyeon ; Min, Ja Kim ; Ahn, Hyeong Sik. / Incidence and epidemiological characteristics of 2009 pandemic influenza A (H1N1) among school-based populations in Korea. In: Infection and Chemotherapy. 2012 ; Vol. 44, No. 6. pp. 431-438.
@article{ff64a482a9f341aabfc5ce97c3daf640,
title = "Incidence and epidemiological characteristics of 2009 pandemic influenza A (H1N1) among school-based populations in Korea",
abstract = "Background: During the 2009 influenza pandemic in Korea, school-age children were mostly attacked by the novel influenza A virus (H1N1). Nevertheless, there is limited information on the cumulative incidence of the 2009 influenza pandemic among school populations. The aim of this study was to estimate the incidence of 2009 H1N1 influenza and influenza-like illness (ILI), and characterize the epidemiology among school-based populations in Korea. Materials and Methods: This study analyzed the data collected by the daily school influenza reporting system for laboratory-confirmed influenza (H1N1 2009 pdm) and ILI in elementary, middle and high schools in Korea during the period, July 1 to December 20, 2009. Results: Between July 1 and December 20, 2009, a total of 525,668 cases of H1N1 2009 pdm were reported from the schools analyzed. The cumulative incidence of H1N1 2009 pdm was highest in elementary school children between 8 and 13 years of age (11,058 per 100,000 population), followed by middle school students between 14 and 16 years of age (10,080 per 100,000), and high school students between 17 and 19 years of age (8,886 per 100,000). With the alignment of the epidemic curves by the three levels of school education, the age group-specific differences in the timing of the infection became apparent. The infections peaked 1 week earlier in both middle and high school students (November 3, 2009) than in elementary school children (November 10, 2009). The infections occurred an average of 7.3 [95{\%} confidence interval(CI): 7.2-7.4] and 3.4 (95{\%} CI: 3.3-3.5) days earlier in the middle and high school students, respectively, than elementary school children (P<0.001). The overall trend of the epidemic waves from the school reporting system data was similar to that of the national surveillance date from the Korea Centers for Disease Control and Prevention. Conclusions: This study suggests that during the 2009 pandemic, one student in every 10 was infected with H1N1 2009 pdm, which is double that estimated from the national surveillance data. In addition, middle and high school students were important drivers of H1N1 2009 pdm transmission in 2009. During the 2009 influenza pandemic, the daily school reporting system provided valuable information for estimating the incidence as well as the epidemiological characteristics in school-based populations.",
keywords = "H1N1, Incidence, Influenza, Pandemic, School",
author = "Kim, {Hyun Jung} and Byung-Chul Chun and Hann, {Hoo Jae} and Sohn, {Jang Wook} and Kee, {Sae Yoon} and Kim, {Si Hyun} and Jo, {Myoung Youn} and Lee, {Kyung Young} and Lee, {Seok Hyeon} and Min, {Ja Kim} and Ahn, {Hyeong Sik}",
year = "2012",
month = "12",
day = "1",
doi = "10.3947/ic.2012.44.6.431",
language = "English",
volume = "44",
pages = "431--438",
journal = "Infection and Chemotherapy",
issn = "2093-2340",
publisher = "Taehan Kamyom Hakhoe, Taehan Hwahak Yopop Hakhoe",
number = "6",

}

TY - JOUR

T1 - Incidence and epidemiological characteristics of 2009 pandemic influenza A (H1N1) among school-based populations in Korea

AU - Kim, Hyun Jung

AU - Chun, Byung-Chul

AU - Hann, Hoo Jae

AU - Sohn, Jang Wook

AU - Kee, Sae Yoon

AU - Kim, Si Hyun

AU - Jo, Myoung Youn

AU - Lee, Kyung Young

AU - Lee, Seok Hyeon

AU - Min, Ja Kim

AU - Ahn, Hyeong Sik

PY - 2012/12/1

Y1 - 2012/12/1

N2 - Background: During the 2009 influenza pandemic in Korea, school-age children were mostly attacked by the novel influenza A virus (H1N1). Nevertheless, there is limited information on the cumulative incidence of the 2009 influenza pandemic among school populations. The aim of this study was to estimate the incidence of 2009 H1N1 influenza and influenza-like illness (ILI), and characterize the epidemiology among school-based populations in Korea. Materials and Methods: This study analyzed the data collected by the daily school influenza reporting system for laboratory-confirmed influenza (H1N1 2009 pdm) and ILI in elementary, middle and high schools in Korea during the period, July 1 to December 20, 2009. Results: Between July 1 and December 20, 2009, a total of 525,668 cases of H1N1 2009 pdm were reported from the schools analyzed. The cumulative incidence of H1N1 2009 pdm was highest in elementary school children between 8 and 13 years of age (11,058 per 100,000 population), followed by middle school students between 14 and 16 years of age (10,080 per 100,000), and high school students between 17 and 19 years of age (8,886 per 100,000). With the alignment of the epidemic curves by the three levels of school education, the age group-specific differences in the timing of the infection became apparent. The infections peaked 1 week earlier in both middle and high school students (November 3, 2009) than in elementary school children (November 10, 2009). The infections occurred an average of 7.3 [95% confidence interval(CI): 7.2-7.4] and 3.4 (95% CI: 3.3-3.5) days earlier in the middle and high school students, respectively, than elementary school children (P<0.001). The overall trend of the epidemic waves from the school reporting system data was similar to that of the national surveillance date from the Korea Centers for Disease Control and Prevention. Conclusions: This study suggests that during the 2009 pandemic, one student in every 10 was infected with H1N1 2009 pdm, which is double that estimated from the national surveillance data. In addition, middle and high school students were important drivers of H1N1 2009 pdm transmission in 2009. During the 2009 influenza pandemic, the daily school reporting system provided valuable information for estimating the incidence as well as the epidemiological characteristics in school-based populations.

AB - Background: During the 2009 influenza pandemic in Korea, school-age children were mostly attacked by the novel influenza A virus (H1N1). Nevertheless, there is limited information on the cumulative incidence of the 2009 influenza pandemic among school populations. The aim of this study was to estimate the incidence of 2009 H1N1 influenza and influenza-like illness (ILI), and characterize the epidemiology among school-based populations in Korea. Materials and Methods: This study analyzed the data collected by the daily school influenza reporting system for laboratory-confirmed influenza (H1N1 2009 pdm) and ILI in elementary, middle and high schools in Korea during the period, July 1 to December 20, 2009. Results: Between July 1 and December 20, 2009, a total of 525,668 cases of H1N1 2009 pdm were reported from the schools analyzed. The cumulative incidence of H1N1 2009 pdm was highest in elementary school children between 8 and 13 years of age (11,058 per 100,000 population), followed by middle school students between 14 and 16 years of age (10,080 per 100,000), and high school students between 17 and 19 years of age (8,886 per 100,000). With the alignment of the epidemic curves by the three levels of school education, the age group-specific differences in the timing of the infection became apparent. The infections peaked 1 week earlier in both middle and high school students (November 3, 2009) than in elementary school children (November 10, 2009). The infections occurred an average of 7.3 [95% confidence interval(CI): 7.2-7.4] and 3.4 (95% CI: 3.3-3.5) days earlier in the middle and high school students, respectively, than elementary school children (P<0.001). The overall trend of the epidemic waves from the school reporting system data was similar to that of the national surveillance date from the Korea Centers for Disease Control and Prevention. Conclusions: This study suggests that during the 2009 pandemic, one student in every 10 was infected with H1N1 2009 pdm, which is double that estimated from the national surveillance data. In addition, middle and high school students were important drivers of H1N1 2009 pdm transmission in 2009. During the 2009 influenza pandemic, the daily school reporting system provided valuable information for estimating the incidence as well as the epidemiological characteristics in school-based populations.

KW - H1N1

KW - Incidence

KW - Influenza

KW - Pandemic

KW - School

UR - http://www.scopus.com/inward/record.url?scp=84872870461&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84872870461&partnerID=8YFLogxK

U2 - 10.3947/ic.2012.44.6.431

DO - 10.3947/ic.2012.44.6.431

M3 - Article

AN - SCOPUS:84872870461

VL - 44

SP - 431

EP - 438

JO - Infection and Chemotherapy

JF - Infection and Chemotherapy

SN - 2093-2340

IS - 6

ER -