Sir Liam said that GPs could be moved around the country to help relieve pressure on flu hotspots and that non-essential work would be suspended.
He also advised that pregnant women might wish to avoid large densely populated gatherings when the spread of swine flu reaches its peak.
But Sir Liam said that school closures would be unlikely because of the extreme disruption it would create.
His comments come as a 15-year-old girl from Glasgow becomes the latest victim of swine flu.
The teenager was suffering from underlying health problems and is the fourth person to die from the virus in Scotland and the 30th death in the UK.
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