Re: 2009 A(H1N1) pandemic likely claimed quarter of a million lives: study
Re: 2009 A(H1N1) pandemic likely claimed quarter of a million lives: study
The Lancet Infectious Diseases, Early Online Publication, 26 June 2012doi:10.1016/S1473-3099(12)70121-4Cite or Link Using DOIEstimated global mortality associated with the first 12 months of 2009 pandemic influenza A H1N1 virus circulation: a modelling study
Original Text
Dr Fatimah S Dawood MD a , A Danielle Iuliano PhD a, Carrie Reed DSc a, Martin I Meltzer PhD b, David K Shay MD a, Po-Yung Cheng PhD a, Don Bandaranayake MBBS c, Robert F Breiman MD d, W Abdullah Brooks MD e f, Philippe Buchy MD g, Daniel R Feikin MD d, Karen B Fowler DrPH h, Aubree Gordon PhD i j, Nguyen Tran Hien MD k, Peter Horby MBBS l, Q Sue Huang PhD c, Mark A Katz MD d, Anand Krishnan MBBS m, Renu Lal PhD a, Joel M Montgomery PhD a n, K?re M?lbak MD o, Richard Pebody MBBS p, Anne M Presanis PhD p, Hugo Razuri MD n, Anneke Steens MSc q, Yeny O Tinoco DVM n, Jacco Wallinga PhD q, Hongjie Yu MD r, Sirenda Vong MD s, Joseph Bresee MD a, Dr Marc-Alain Widdowson VetMB a
Summary
Background
18 500 laboratory-confirmed deaths caused by the 2009 pandemic influenza A H1N1 were reported worldwide for the period April, 2009, to August, 2010. This number is likely to be only a fraction of the true number of the deaths associated with 2009 pandemic influenza A H1N1. We aimed to estimate the global number of deaths during the first 12 months of virus circulation in each country.
Methods
We calculated crude respiratory mortality rates associated with the 2009 pandemic influenza A H1N1 strain by age (0?17 years, 18?64 years, and >64 years) using the cumulative (12 months) virus-associated symptomatic attack rates from 12 countries and symptomatic case fatality ratios (sCFR) from five high-income countries. To adjust crude mortality rates for differences between countries in risk of death from influenza, we developed a respiratory mortality multiplier equal to the ratio of the median lower respiratory tract infection mortality rate in each WHO region mortality stratum to the median in countries with very low mortality. We calculated cardiovascular disease mortality rates associated with 2009 pandemic influenza A H1N1 infection with the ratio of excess deaths from cardiovascular and respiratory diseases during the pandemic in five countries and multiplied these values by the crude respiratory disease mortality rate associated with the virus. Respiratory and cardiovascular mortality rates associated with 2009 pandemic influenza A H1N1 were multiplied by age to calculate the number of associated deaths.
Findings
We estimate that globally there were 201 200 respiratory deaths (range 105 700?395 600) with an additional 83 300 cardiovascular deaths (46 000?179 900) associated with 2009 pandemic influenza A H1N1. 80% of the respiratory and cardiovascular deaths were in people younger than 65 years and 59% occurred in southeast Asia and Africa.Interpretation
Our estimate of respiratory and cardiovascular mortality associated with the 2009 pandemic influenza A H1N1 was 15 times higher than reported laboratory-confirmed deaths. Although no estimates of sCFRs were available from Africa and southeast Asia, a disproportionate number of estimated pandemic deaths might have occurred in these regions. Therefore, efforts to prevent influenza need to effectively target these regions in future pandemics.
Funding
None.
http://www.thelancet.com/journals/laninf/article/PIIS1473-3099(12)70121-4/fulltext