A report indicates that hospitals in 15 states could run out of beds due to swine flu.
The first round of swine flu vaccine has been shipped to 25 states.
Swine flu vaccinations will begin this month in the UK as well.
Scotland's health minister is warning of an imminent new round of swine flu cases there.
New research finds that sons of pregnant women who contracted the swine flu during the 1918 pandemic were more likely to have life-long health problems.