H1N1 swine flu attacks the respiratory system in a more sustained way than the standard seasonal virus, research in animals shows.

Tests showed swine flu multiplies in greater numbers across the respiratory system, and causes more damage.

And instead of staying in the head like seasonal flu, it penetrates deeper into the respiratory tissues – making it more likely to cause pneumonia.

The University of Wisconsin study appears in the journal Nature.

It also suggests that swine flu may mimic the flu virus which caused the great pandemic of 1918, in which millions died.

The 1918 virus also had a greater ability than standard flu to cause damage to the respiratory system.

via BBC NEWS.