(HealthDay News) – The estimated number of global respiratory and cardiovascular deaths associated with the 2009 pandemic influenza A H1N1 is higher than the number of laboratory-confirmed deaths.
Noting that 18,500 laboratory-confirmed deaths caused by influenza A H1N1 were reported worldwide for April 2009–August 2010, Fatima S. Dawood, MD, from the US Centers for Disease Control and Prevention in Atlanta, and colleagues estimated the global number of deaths during the first 12 months of virus circulation. The cumulative virus-associated symptomatic attack rates from 12 countries and case fatality ratios from five high-income countries were used to calculate the crude respiratory mortality rates. Cardiovascular disease mortality rates associated with influenza A H1N1 infection were calculated using the ratio of excess deaths from cardiovascular and respiratory disease during the pandemic in five countries. To calculate the number of deaths, the mortality rates were multiplied by age.
The researchers identified 201,200 2009 pandemic influenza A H1N1-associated respiratory deaths and 83,300 influenza A H1N1-associated cardiovascular deaths, globally. Fifty-one percent of respiratory and cardiovascular deaths occurred in southeast Asia and Africa and 80% were in individuals <65 years.
“Our findings emphasize the need to improve the global response to future influenza pandemics and expand production and improve delivery of influenza vaccines to Africa and southeast Asia because these countries might have borne a disproportionate burden of pandemic mortality during the first year of virus circulation,” the authors write.