RESEARCH ARTICLE
Interim estimates of the effectiveness of the influenza vaccine against A(H3N2) influenza in adults in South Korea, 2016–2017 season Ji Yun Noh1,2☯, Sooyeon Lim2☯, Joon Young Song1,2, Won Suk Choi1,2, Hye Won Jeong3, Jung Yeon Heo3, Jacob Lee4, Yu Bin Seo4, Jin-Soo Lee5, Seong Heon Wie6, Young Keun Kim7, Kyung Hwa Park8, Sook-In Jung8, Shin Woo Kim9, Sun Hee Lee10, Han Sol Lee11, Young Hoon Yoon12, Hee Jin Cheong1,2, Woo Joo Kim1,2,11*
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OPEN ACCESS Citation: Noh JY, Lim S, Song JY, Choi WS, Jeong HW, Heo JY, et al. (2017) Interim estimates of the effectiveness of the influenza vaccine against A (H3N2) influenza in adults in South Korea, 2016– 2017 season. PLoS ONE 12(5): e0178010. https:// doi.org/10.1371/journal.pone.0178010 Editor: Benjamin J. Cowling, University of Hong Kong, HONG KONG Received: February 8, 2017 Accepted: May 6, 2017 Published: May 25, 2017 Copyright: © 2017 Noh et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All sequences of influenza viruses in this study are available from the GenBank (accession number KY486332KY486360, KY509560, KY509561, KY509569, KY509570, KY509577, KY509578, KY509597, KY509598, KY509670, KY509675-KY509677, KY509679, KY509682-KY509684, KY509694, KY509696, KY509725, KY509726).
1 Division of Infectious Diseases, Department of Internal Medicine, Korea University College of Medicine, Seoul, South Korea, 2 Asia Pacific Influenza Institute, Korea University College of Medicine, Seoul, South Korea, 3 Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, Chungbuk National University, Cheongju, South Korea, 4 Division of Infectious Diseases, Department of Internal Medicine, Kangnam Sacred Heart Hospital, Hallym University School of Medicine, Chuncheon, South Korea, 5 Division of Infectious Diseases, Department of Internal Medicine, Inha University College of Medicine, Incheon, South Korea, 6 Division of Infectious Diseases, Department of Internal Medicine, The Catholic University of Korea, School of Medicine, St. Vincent’s Hospital, Suwon, South Korea, 7 Department of Infectious Diseases, Yonsei University Wonju College of Medicine, Wonju, South Korea, 8 Department of Internal Medicine, Chonnam National University Medical School, Gwangju, South Korea, 9 Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, South Korea, 10 Department of Internal Medicine, Pusan National University School of Medicine, Busan, South Korea, 11 Brain Korea 21 Plus for Biomedical Science, Korea University College of Medicine, Seoul, South Korea, 12 Department of Emergency Medicine, Korea University College of Medicine, Seoul, South Korea ☯ These authors contributed equally to this work. * [email protected]
Abstract In the 2016–2017 season, the A(H3N2) influenza epidemic presented an unusual early peak pattern compared with past seasons in South Korea. The interim vaccine effectiveness (VE) of influenza vaccination in preventing laboratory-confirmed influenza was estimated using test-negative design through the tertiary hospital-based influenza surveillance system in South Korea. From 1 September, 2016 to 7 January, 2017, adjusted VE of influenza vaccination in preventing laboratory-confirmed A(H3N2) was -52.1% (95% confidence interval [CI], -147.2 to 6.4); -70.0% (95% CI, -212.0 to 7.4) in 19–64 years and 4.3% (95% CI, -137.8 to 61.5) in the elderly. Circulating A(H3N2) viruses belonged to the three phylogenetic subclades of 3C.2a, differently to A/Hong Kong/4801/2014, the current vaccine strain. Amino acid substitutions in hemagglutinin of circulating viruses seem to contribute to low VE. In conclusion, interim VE analysis presented that the protection of laboratory-confirmed influenza by seasonal influenza vaccination did not show the statistical significance in South Korea in the 2016–2017 influenza season.
Funding: This work was supported by a grant of the TEPIK (Transgovernmental Enterprise for Pandemic Influenza in Korea)‚ which is a part of the
PLOS ONE | https://doi.org/10.1371/journal.pone.0178010 May 25, 2017
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Interim seasonal influenza vaccine effectiveness in Korea
Korea Healthcare Technology R&D Project by Ministry of Health & Welfare, Republic of Korea (Grant no.: A103001) and by the National Research Foundation of Korea (NRF) Grant funded by the Korean Government (MSIP) (NRF2016R1A5A1010148). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: The authors have declared that no competing interests exist.
Introduction Influenza has been considered major medically attended acute febrile respiratory illness in humans. Antigenic variation is responsible for influenza being a continuous concern for public health. The 2016–2017 influenza season in South Korea has been characterized by an exceptionally early epidemic of A(H3N2) influenza in December, 2016. A primary clinic-based sentinel surveillance conducted by the Korea Centers for Disease Control and Prevention (KCDC) reported that all the detected influenza viruses up to the week 1 (1 to 7 January, 2017) during the 2016–2017 influenza season were identified as A(H3N2) [1]. Vaccination is the primary strategy used to reduce the disease burden associated with influenza. Persons at a higher risk for influenza-related morbidity are recommended to be vaccinated against seasonal influenza with priority by KCDC in South Korea: persons who have chronic pulmonary disease or chronic heart disease; residents of nursing homes or long-term care facilities who have chronic medical diseases; persons who have chronic hepatic disease, chronic kidney disease, neuromuscular disorder, malignancy, diabetes mellitus, immunocompromised patients, children and adolescents (aged 6 months to 18 years) who are receiving aspirin therapy; persons aged 65 years; healthcare workers; household contacts of persons with chronic medical conditions, pregnant women and the elderly; caregivers of children aged
Interim estimates of the effectiveness of the influenza vaccine against A(H3N2) influenza in adults in South Korea, 2016–2017 season Ji Yun Noh1,2☯, Sooyeon Lim2☯, Joon Young Song1,2, Won Suk Choi1,2, Hye Won Jeong3, Jung Yeon Heo3, Jacob Lee4, Yu Bin Seo4, Jin-Soo Lee5, Seong Heon Wie6, Young Keun Kim7, Kyung Hwa Park8, Sook-In Jung8, Shin Woo Kim9, Sun Hee Lee10, Han Sol Lee11, Young Hoon Yoon12, Hee Jin Cheong1,2, Woo Joo Kim1,2,11*
a1111111111 a1111111111 a1111111111 a1111111111 a1111111111
OPEN ACCESS Citation: Noh JY, Lim S, Song JY, Choi WS, Jeong HW, Heo JY, et al. (2017) Interim estimates of the effectiveness of the influenza vaccine against A (H3N2) influenza in adults in South Korea, 2016– 2017 season. PLoS ONE 12(5): e0178010. https:// doi.org/10.1371/journal.pone.0178010 Editor: Benjamin J. Cowling, University of Hong Kong, HONG KONG Received: February 8, 2017 Accepted: May 6, 2017 Published: May 25, 2017 Copyright: © 2017 Noh et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All sequences of influenza viruses in this study are available from the GenBank (accession number KY486332KY486360, KY509560, KY509561, KY509569, KY509570, KY509577, KY509578, KY509597, KY509598, KY509670, KY509675-KY509677, KY509679, KY509682-KY509684, KY509694, KY509696, KY509725, KY509726).
1 Division of Infectious Diseases, Department of Internal Medicine, Korea University College of Medicine, Seoul, South Korea, 2 Asia Pacific Influenza Institute, Korea University College of Medicine, Seoul, South Korea, 3 Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, Chungbuk National University, Cheongju, South Korea, 4 Division of Infectious Diseases, Department of Internal Medicine, Kangnam Sacred Heart Hospital, Hallym University School of Medicine, Chuncheon, South Korea, 5 Division of Infectious Diseases, Department of Internal Medicine, Inha University College of Medicine, Incheon, South Korea, 6 Division of Infectious Diseases, Department of Internal Medicine, The Catholic University of Korea, School of Medicine, St. Vincent’s Hospital, Suwon, South Korea, 7 Department of Infectious Diseases, Yonsei University Wonju College of Medicine, Wonju, South Korea, 8 Department of Internal Medicine, Chonnam National University Medical School, Gwangju, South Korea, 9 Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, South Korea, 10 Department of Internal Medicine, Pusan National University School of Medicine, Busan, South Korea, 11 Brain Korea 21 Plus for Biomedical Science, Korea University College of Medicine, Seoul, South Korea, 12 Department of Emergency Medicine, Korea University College of Medicine, Seoul, South Korea ☯ These authors contributed equally to this work. * [email protected]
Abstract In the 2016–2017 season, the A(H3N2) influenza epidemic presented an unusual early peak pattern compared with past seasons in South Korea. The interim vaccine effectiveness (VE) of influenza vaccination in preventing laboratory-confirmed influenza was estimated using test-negative design through the tertiary hospital-based influenza surveillance system in South Korea. From 1 September, 2016 to 7 January, 2017, adjusted VE of influenza vaccination in preventing laboratory-confirmed A(H3N2) was -52.1% (95% confidence interval [CI], -147.2 to 6.4); -70.0% (95% CI, -212.0 to 7.4) in 19–64 years and 4.3% (95% CI, -137.8 to 61.5) in the elderly. Circulating A(H3N2) viruses belonged to the three phylogenetic subclades of 3C.2a, differently to A/Hong Kong/4801/2014, the current vaccine strain. Amino acid substitutions in hemagglutinin of circulating viruses seem to contribute to low VE. In conclusion, interim VE analysis presented that the protection of laboratory-confirmed influenza by seasonal influenza vaccination did not show the statistical significance in South Korea in the 2016–2017 influenza season.
Funding: This work was supported by a grant of the TEPIK (Transgovernmental Enterprise for Pandemic Influenza in Korea)‚ which is a part of the
PLOS ONE | https://doi.org/10.1371/journal.pone.0178010 May 25, 2017
1 / 11
Interim seasonal influenza vaccine effectiveness in Korea
Korea Healthcare Technology R&D Project by Ministry of Health & Welfare, Republic of Korea (Grant no.: A103001) and by the National Research Foundation of Korea (NRF) Grant funded by the Korean Government (MSIP) (NRF2016R1A5A1010148). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: The authors have declared that no competing interests exist.
Introduction Influenza has been considered major medically attended acute febrile respiratory illness in humans. Antigenic variation is responsible for influenza being a continuous concern for public health. The 2016–2017 influenza season in South Korea has been characterized by an exceptionally early epidemic of A(H3N2) influenza in December, 2016. A primary clinic-based sentinel surveillance conducted by the Korea Centers for Disease Control and Prevention (KCDC) reported that all the detected influenza viruses up to the week 1 (1 to 7 January, 2017) during the 2016–2017 influenza season were identified as A(H3N2) [1]. Vaccination is the primary strategy used to reduce the disease burden associated with influenza. Persons at a higher risk for influenza-related morbidity are recommended to be vaccinated against seasonal influenza with priority by KCDC in South Korea: persons who have chronic pulmonary disease or chronic heart disease; residents of nursing homes or long-term care facilities who have chronic medical diseases; persons who have chronic hepatic disease, chronic kidney disease, neuromuscular disorder, malignancy, diabetes mellitus, immunocompromised patients, children and adolescents (aged 6 months to 18 years) who are receiving aspirin therapy; persons aged 65 years; healthcare workers; household contacts of persons with chronic medical conditions, pregnant women and the elderly; caregivers of children aged
