Introduction
It is important to determine the health impact of influenza in order to calibrate
public health measures. The objective of this study was to estimate excess mortality
associated with influenza in Korea in 2003–2013.
Methods
The authors constructed multiple linear regression models in 2014 with weekly mortality
rates stratified by age, region, and cause of death against weekly surveillance data
on influenza virus collected in 2003–2013. Excess mortality rates were estimated using
the difference between predicted mortality rates from the fitted model versus predicted
mortality rates with the influenza covariate for each strain set to 0.
Results
During the study period, influenza was associated with an average of 2,900 excess
deaths per year. The impact of influenza on mortality was significantly higher in
older people; the overall all-cause excess annual mortality rate per 100,000 people
was 5.97 (95% CI=4.89, 7.19), whereas it was 46.98 (95% CI=36.40, 55.82) for adults
aged ≥65 years. It also greatly varied from year to year, ranging from 2.04 in 2009–2010
to 18.76 in 2011–2012.
Conclusions
The impact of influenza on mortality in Korea is substantial, particularly among the
elderly and the rural population. More-comprehensive studies may be needed to estimate
the full impact of influenza.
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to American Journal of Preventive MedicineAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- Vaccines against influenza WHO position paper—November 2012.Wkly Epidemiol Rec. 2012; 87: 461-476
WHO. Influenza: fact sheets. www.who.int/mediacentre/factsheets/2003/fs211/en/. Accessed January 15, 2015.
- The annual impact of seasonal influenza in the U.S.: measuring disease burden and costs.Vaccine. 2007; 25: 5086-5096https://doi.org/10.1016/j.vaccine.2007.03.046
- Hospital-based influenza surveillance in Korea: hospital-based influenza morbidity and mortality study group.J Med Virol. 2013; 85: 910-917https://doi.org/10.1002/jmv.23548
- Influenza-related hospitalizations among children in Hong Kong.N Engl J Med. 2002; 347: 2097-2103https://doi.org/10.1056/NEJMoa020546
- Influenza-associated mortality in Hong Kong.Clin Infect Dis. 2004; 39: 1611-1617https://doi.org/10.1086/425315
- Mortality due to influenza in the United States—an annualized regression approach using multiple-cause mortality data.Am J Epidemiol. 2006; 163: 181-187https://doi.org/10.1093/aje/kwj024
- Estimates of US influenza-associated deaths made using four different methods.Influenza Other Respir Viruses. 2009; 3: 37-49https://doi.org/10.1111/j.1750-2659.2009.00073.x
- Estimating influenza-associated deaths in the United States.Am J Public Health. 2009; 99: S225-S230https://doi.org/10.2105/AJPH.2008.151944
Muscatello DJ, Cretikos MA, Macintyre CR. All-cause mortality during first wave of pandemic (H1N1) 2009, New South Wales, Australia, 2009. Emerg Infect Dis. 2010;16(9):1396–1402. http://dx.doi.org/10.3201/eid1609.091723.
- Elevated influenza-related excess mortality in South African elderly individuals, 1998-2005.Clin Infect Dis. 2010; 51: 1362-1369https://doi.org/10.1086/657314
- Predicting the epidemic sizes of influenza A/H1N1, A/H3N2, and B: a statistical method.PLoS Med. 2011; 8: e1001051https://doi.org/10.1371/journal.pmed.1001051
- Comparing pandemic to seasonal influenza mortality: moderate impact overall but high mortality in young children.PLoS One. 2012; 7: e31197https://doi.org/10.1371/journal.pone.0031197
- Global mortality estimates for the 2009 Influenza Pandemic from the GLaMOR project: a modeling study.PLoS Med. 2013; 10: e1001558https://doi.org/10.1371/journal.pmed.1001558
- Circulating influenza virus, climatic factors, and acute myocardial infarction: a time series study in England and Wales and Hong Kong.J Infect Dis. 2011; 203: 1710-1718https://doi.org/10.1093/infdis/jir171
- Improving the estimation of influenza-related mortality over a seasonal baseline.Epidemiology. 2012; 23: 829-838https://doi.org/10.1097/EDE.0b013e31826c2dda
- Excess mortality associated with influenza A and B virus in Hong Kong, 1998-2009.J Infect Dis. 2012; 206: 1862-1871https://doi.org/10.1093/infdis/jis628
- Mortality burden of the A/H1N1 pandemic in Mexico: a comparison of deaths and years of life lost to seasonal influenza.Clin Infect Dis. 2011; 53: 985-993https://doi.org/10.1093/cid/cir644
- Mortality burden of the 2009 A/H1N1 influenza pandemic in France: comparison to seasonal influenza and the A/H3N2 pandemic.PLoS One. 2012; 7: e45051https://doi.org/10.1371/journal.pone.0045051
- Influenza-associated excess mortality in southern Brazil, 1980-2008.Epidemiol Infect. 2013; 141: 1731-1740https://doi.org/10.1017/S0950268812002221
- Excess mortality associated with influenza epidemics in Portugal, 1980 to 2004.PLoS One. 2011; 6: e20661https://doi.org/10.1371/journal.pone.0020661
- Excess mortality related to seasonal influenza and extreme temperatures in Denmark, 1994-2010.BMC Infect Dis. 2011; 11: 350https://doi.org/10.1186/1471-2334-11-350
- Influenza-associated mortality in temperate and subtropical Chinese cities, 2003-2008.Bull World Health Organ. 2012; 90: 279-288bhttps://doi.org/10.2471/BLT.11.096958
- Influenza associated mortality in the subtropics and tropics: results from three Asian cities.Vaccine. 2011; 29: 8909-8914https://doi.org/10.1016/j.vaccine.2011.09.071
- Estimating influenza-associated mortality in New Zealand from 1990 to 2008.Influenza Other Respir Viruses. 2015; 9: 14-19https://doi.org/10.1111/irv.12292
Korean Statistical Information Service (KOSIS). Statistical Database. Korea Statistics.
- Influenza infection and COPD.Int J Chron Obstruct Pulmon Dis. 2007; 2: 55-64https://doi.org/10.2147/copd.2007.2.1.55
- Influenza and the winter increase in mortality in the United States, 1959-1999.Am J Epidemiol. 2004; 160: 492-502https://doi.org/10.1093/aje/kwh227
- Influenza-related deaths—available methods for estimating numbers and detecting patterns for seasonal and pandemic influenza in Europe.Euro Surveill. 2012; 17
Korea Centers for Disease Control and Prevention (KCDC). Influenza Weekly/Annual Report. www.cdc.go.kr/CDC/info/CdcKrInfo0402.jsp?menuIds=HOME001-MNU1132-MNU1138-MNU0045. Accessed May 30, 2014.
Korea Centers for Disease Control and Prevention (KCDC). Disease Web Statistics System: Weekly ILI Rate. http://is.cdc.go.kr/dstat/jsp/stat/stat0101.jsp. Accessed May 30, 2014.
Korea Meteorological Administration (KMA). Archive of daily weather. www.kma.go.kr/weather/climate/past_table.jsp. Accessed June 2, 2014.
- Absolute humidity modulates influenza survival, transmission, and seasonality.Proc Natl Acad Sci U S A. 2009; 106: 3243-3248https://doi.org/10.1073/pnas.0806852106
- Absolute humidity, temperature, and influenza mortality: 30 years of county-level evidence from the United States.Am J Epidemiol. 2012; 176: S114-S122https://doi.org/10.1093/aje/kws259
- Comparison of infection rats and severity of illness for influenza A subtypes H1N1 and H3N2.J Infect Dis. 1985; 151: 73-80https://doi.org/10.1093/infdis/151.1.73
- Estimates of deaths associated with seasonal influenza—United States, 1976-2007.MMWR Morb Mortal Wkly Rep. 2010; 59: 1057-1062
Korea Centers for Disease Control and Prevention (KCDC). Analysis of reported pandemic influenza (A/H1N1 2009) virus infections in Korea. KCDC, 2010.
- The spread of pandemic H1N1 2009 by age and region and the comparison among monitoring tools.J Korean Med Sci. 2010; 25: 1109-1112https://doi.org/10.3346/jkms.2010.25.7.1109
Korea Centers for Disease Control and Prevention (KCDC). 2009-2010 Influenza A(H1N1) vaccination program in Korea. KCDC, 2010.
- Preliminary estimates of mortality and years of life lost associated with the 2009 A/H1N1 pandemic in the U.S. and comparison with past influenza seasons.PLoS Curr. 2010; 2: RRN1153https://doi.org/10.1371/currents.RRN1153
Lozano R, Murray CJL, Lopez AD, Satoh T. Miscoding and misclassification of ischaemic heart disease mortality. WHO; 2001.
- Death certificate coding practices related to diabetes in European countries—the “EURODIAB Subarea C” Study.Int J Epidemiol. 1992; 21: 343-351https://doi.org/10.1093/ije/21.2.343
Noymer A, Nguyen AM. Influenza as a proportion of pneumonia mortality: United States, 1959-2009, Biodemogr Soc Biol. 2013;59(2):178–190. 10.1080/19485565.2013.833816.
Korea Centers for Disease Control and Prevention (KCDC). Influenza management guideline (2013-2014), 2013.
Organisation for Economic Co-operation and Development (OECD). OECD StatExtracts: health status. http://stats.oecd.org/index.aspx?DataSetCode=HEALTH_STAT. Accessed January 29, 2015.
Article info
Publication history
Published online: November 20, 2015
Identification
Copyright
© 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
