Vaccines for the 2009 H1N1 virus, or swine flu,
start appearing next week in clinics and doctors'
offices across the country. Health officials are
recommending that the first doses go to the most
vulnerable groups, including pregnant women. Ultimately,
the Centers for Disease Control plans to vaccinate at
least half the American population. It's a race against
not just the spread of the swine flu virus, but also
against its inevitable mutation.Reporter: Amy Standen