Superbug doctors dread arrives in US

WASHINGTON, D.C. (WPVI) -- A superbug doctors have been dreading has reached the U.S.

A strain of E. coli bacteria, resistant to everything short of the antibiotics of last resort, has been found in a 49-year-old Pennsylvania woman.

Neither the woman nor her town have been identified.

But the state health department is interviewing her and her family to find out how she might have contracted it.

Department of Defense health experts are also involved in the investigation.

This superbug was found last year in pigs, raw pork and a small number of people in China.

The strain has appeared in Europe since then.