The number of deaths from the 2009 swine flu pandemic may be 15 times higher than initially calculated, an international team of scientists said in a study published Tuesday by the British journal The Lancet.
While 18,500 deaths from the H1N1 virus had been confirmed by laboratories, new statistical calculations yielded an estimate of 284,500 who died from lung or heart problems, according to the research led by the US government's Centers for Disease Control and Prevention (CDC).
During the swine flu pandemic, the World Health Organization (WHO) in Geneva had been criticized for overestimating the lethal risks from H1N1.
"We said at the time that influenza is dangerous," WHO spokesman Gregory Hartl told dpa. "We always said during the pandemic that it would take one or two years after the pandemic to get estimates."
In their new study, the scientists arrived at a higher number because they assumed that mortality rates were higher in some countries than in others, using average death rates from respiratory diseases, as well as looking at above-average death figures from lung and heart problems.
The study said that more than half of the deaths may have occurred in South-East Asia and Africa.
It said that 80 per cent of those who died in the pandemic between April 2009 and August 2010 were younger than 65.
Lead author Fatimah Dawood at the CDC said she hoped that the research would "improve the public health response during future pandemics in parts of the world that suffer more deaths, and to increase the public's awareness of the importance of influenza prevention."
Copyright 2012 dpa Deutsche Presse-Agentur GmbH