BOSTON Because the 2009 H1N1 virus caused the
most serious morbidity and mortality in those aged younger than 65 years, a
substantial number about 9.9 million of life years were lost,
according to calculations from the CDC.
Fatimah S. Dawood, MD, and colleagues from the
CDC examined data on 2009 H1N1 symptomatic attack rates and fatality ratios
from a number of countries to calculate the median ranges of lower respiratory
tract mortality rates in each WHO region and mortality stratum in the first
year of virus circulation.
Based on their calculations, Dawood and colleagues
estimated that 249,000 (90% CI, 48,000-716,000) 2009 H1N1 deaths occurred
globally, according to a presentation here at the IDSA 49th Annual Meeting.
2009 H1N1 respiratory mortality was at least twofold
higher than reported laboratory-confirmed deaths, and lower resource countries
were disproportionately affected, the researchers wrote in their
They said most of the deaths (58%) occurred in Africa
and Southeast Asia. The researchers estimated that about 216,000 of the deaths
(87%) occurred in those aged younger than 65 years, resulting in an estimated
9.9 million (90% CI 3,933,000-18,820,000) years of life lost.
Although estimated mortality may have been lower
than that of some prior pandemics, the majority of
2009 H1N1 deaths were in persons less than 65 years,
resulting in a substantial number of years of life lost, the researchers
Disclosure: The researchers report no relevant financial
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