A variant of last year's pandemic influenza linked to fatal
cases carried a mutation that enabled it to infect a different
subset of cells lining the airway, according to new research.
The study, due to be published next week in the Journal of
Virology, suggests that the mutant virus could have impaired the
lungs' ability to clear out germs. The researchers behind the
study, from Imperial College London, the Medical Research
Council National Institute for Medical Research and the
University of Marburg said the findings highlight the potential
for deadlier strains of flu to emerge and spread. The 2009
pandemic of H1N1 influenza caused thousands of deaths worldwide,
but the majority of cases were relatively mild. A variant of the
virus carried a mutation termed D222G in a protein on the
surface of the virus, and people infected with this variant were
more likely to have severe and fatal illness. According to a
World Health Organisation report, the D222G mutation was found
in less than two in every hundred cases