用英文介绍最近的一则新闻，简单一点

Can Swine Flu Be Blamed on Industrial Farming?
Amidst the hubbub surrounding the current pandemic threat from swine flu,
an epidemiological mystery has been unfolding.Authorities have designated
Edgar Hernandez,a fiveyearold from La Gloria in the Mexican state of
Veracruz as "Patient Zero"at least he is the earliest case they have found
so far.Virologists have determined that the mutating flu is a combination
of several older flu strains,commonly associated with pigs.And La Gloria
is home to nearly a million pigs on a nearby factory farm.
So is socalled swine flu really just another environmental problem associated
with factory farming?
After all,such large operations keep the animals in close confinement,dope
them with antibiotics to keep them alive in the crowded conditions and create