Between 123,000 and 203,000 pandemic influenza respiratory deaths occurred globally between 1 April and 31 December 2009, according to a study by international researchers from the GLaMOR project published in PLOS Medicine. In this modeling study, led by Lone Simonsen Lone Simonsen from George Washington University School of Public Health and Health Services in the United States, the researchers estimated the global burden of the 2009 Influenza pandemic by combining weekly virology data from the World Health Organization FluNet database and national influenza centers with weekly national underlying cause-of-death time series for 2005-2009 obtained from collaborators in more than 20 countries that cover 35% of the world's population.
The findings from this study suggest that respiratory mortality from the 2009 influenza pandemic was about 10-fold higher than laboratory-confirmed deaths. The authors found that most of the influenza deaths (62%-85%) occurred in people younger than 65, with the greatest mortality burden in Central and South American countries and lowest burden in European countries.
The authors say: "The burden varied greatly among countries, corroborating early reports of far greater pandemic severity in the Americas than in Australia, New Zealand, and Europe. A collaborative network to collect and analyze mortality and hospitalization surveillance data is needed to rapidly establish the severity of future pandemics."