MRSA killed 19,000 Americans in 2005 (17,000 died of AIDS in the same period) and incidence is on the rise largely due to CAFOs and their indiscriminate use of antibiotics, without which the animals would probably die in mass numbers. Instead they become food for most Americans.
ACRES USA reports further that the bacteria was found on 45% of the farms in Ontario, 25% of the pigs, and 20% of the farmers. Attendees at the 2005 International Veterinary Convention were tested for the disease and of the 27 positives, 23 were Americans. 81% of all Dutch hog farms had one or more infected pigs and 39% of pigs at slaughter carried the bacteria and Dutch pig farmers had 760 times as much as regular patients admitted to hospitals. The greatest incidence occurred on farms where large amounts of antibiotics were used (duh). No one is systematically testing for it in the USA.
Here's a treatment for the flesh-eating bug from, oddly, Wired magazine.