Was the Mass Vaccination Effective During the Influenza Pandemic 2009–2010 in Korea?

Article information

Osong Public Health Res Perspect. 2013;4(4):177-178
Publication date (electronic) : 2013 July 26
doi : https://doi.org/10.1016/j.phrp.2013.07.003
Editor-in-Chief, Dean, Professor, Osong Public Health and Research Perspectives,Osong, South Korea
College of Health, Eulji University, Seongnam, South Korea
College of Medicine, Eulji University, Daejeon, South Korea
Managing Editor, Osong Public Health and Research Perspectives, Osong, South Korea
Corresponding author. hwcho@eulji.ac.kr
Corresponding author. cchu@cdc.go.kr

The influenza A/H1N1 pandemic in 2009–2010 had a huge impact on scientists and public health authorities in the public health sector of Korea before and after the event. Laboratory scientists traced the pathogenesis and chronological localization of influenza A/H1N1 [1], and also checked antiviral resistance in Korea [2]. Surveillance data on influenza-like illness (ILI) were utilized to estimate the number of influenza patients in Korea [3]. Mathematical modelers evaluated the parameters of the existing preparedness plans in Korea [4].

In this issue, two studies deal with the effectiveness of vaccination against the H1N1pdm09 virus. One study was conducted under a military setting to measure its effectiveness [5]. The H1N1pdm09 vaccine, which was administered in January 2010, had approximately 50% effectiveness against the H1N1pdm09 outbreak that occurred in December 2010. The magnitude of vaccination effectiveness was robust with no substantial difference, even when multivariate analysis and various ILI definitions were used.

The magnitude of vaccine effectiveness was lower in this study than the 70% effectiveness during the H1N1pdm09 season (2009–2010) in previous studies, but was similar to the effectiveness during the following season (2010–2011) in previous studies. Studies that evaluated the vaccination effectiveness 1 year after a vaccination program have indicated that the vaccination effectiveness was not persistent because there were no statistically significant results [6,7]. However, the current study showed that there was still a statistically significant vaccination effectiveness 1 year after the vaccination. This was immunologically consistent with the results of an existing antigenicity study in which the vaccination effectiveness was persistent 1 year after seasonal influenza vaccination, although the antibody titer decreased [8].

This study has shown a unique approach to evaluate the effectiveness of mass vaccination in Korea. This evaluation would provide a valuable insight for public health officials and scientists to prepare for the next possible pandemic in Korea.


1. Kwon D., Shin K., Shin J.-Y.. Pahtogenesis and chronologic localization of the human influenza A (H1N1) virus in cotton rats. Osong Public Health Res Perspect 2(1)2011 Jun;:15–22.
2. Choi W.-Y., Yang I., Kim S.. The emergence of oseltamivir-resistant seasonal influenza A (H1N1) virus in Korea during the 2008–2009 season. Osong Public Health Res Perspect 2(2)2011 Sep;:178–185.
3. Lee J.S., Park S.-H., Moon J.-W.. Modeling for estimating influenza patients from ILI surveillance data in Korea. Osong Public Health Res Perspect 2(2)2011 Sep;:89–93.
4. Chu C., Lee J., Choi D.H.. Sensitivity analysis of the parameters of Korea’s pandemic influenza plan. Osong Public Health Res Perspect 2(3)2011 Dec;:210–215.
5. Kim K.-Y., Choi Y.G., Yoon H.-B.. Evaluation of the effectiveness of pandemic influenza A(H1N1) 2009 vaccine based on an outbreak investigation during the 2010 – 2011 season in Korean military camps. Osong Public Health Res Perspect 4(4)2013 Aug;:209–214.
6. Pebody R., Hardelid P., Fleming D.M.. Effectiveness of seasonal 2010/11 and pandemic influenza A(H1N1)2009 vaccines in preventing influenza infection in the United Kingdom: mid-season analysis 2010/11. Euro Surveill 16(6)2011 Feb 10;pii: 19791.
7. Fielding J.E., Grant K.A.. Effectiveness of seasonal influenza vaccine against pandemic (H1N1) 2009 virus, Australia. Emerg Infect Dis 2011 Jul 17(7)2010;:1181–1187.
8. Song J.Y., Cheong H.J., Hwang I.S.. Long-term immunogenicity of influenza vaccine among the elderly: risk factors for poor immune response and persistence. Vaccine 28(23)2010 May 21;:3929–3935. 20394719.


This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Article information Continued