Deaths from H1N1 influenza in 2009 may have been 10 times higher than previously estimated, killing 123,000 to 203,000 people from respiratory illness worldwide, according to a new analysis in the journal PLOS Medicine.
The World Health Organization had listed the global death toll from the H1N1 pandemic, also known as swine flu, at 18,449, based only on laboratory-confirmed cases.
That relatively low death tally had led some to wonder if the dangers of H1N1 had been overblown, according to the analysis, conducted by 60 researchers in 26 countries and funded by the WHO.
Most people infected with the flu never got a lab test to confirm their diagnosis, according to the study, whose authors used death records from countries around the world to estimate the true number of deaths.
Some flu deaths go uncounted, because the immediate cause of death of many people is actually pneumonia or another chronic respiratory ailment, according to the study led by researchers at George Washington University School of Public Health in Washington.
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