A new "untreatable" strain of E.coli that is drug resistant, called ST131, has made its way into the United States and doctors fear that this strain could pose a significant threat to Americans, according to reports on www.examiner.com.

Researchers have determined that the new strain is resistant to antibiotics in class of fluoroquinolone and cephalosporin.

This strain has effected several countries and the United States thus far.

"If this strain gains one additional resistance gene, it will become almost untreatable and will be a true superbug, which is a very concerning scenario," Dr. James Johnson of the VA Medical Center in Minneapolis, who led the study, said in a statement.

There were samples taken from 127 patients that were affected by this e.coli strain and 54 of them showed the ST131 strain.

Scientists are not sure how this new strain is transmitted or the source of the strain.

According to the Centers for Disease Control and Prevention, some strains are actually harmless, while others can make people sick.  Different types of strains have a variety of symptoms including diarrhea, while others cause urinary tract infections, respiratory illness and pneumonia, and other illnesses.