More cases of superbug precursor reported, but no spread

FILE - In this Monday, Nov. 25, 2013 file photo, a microbiologist works with tubes of bacteria samples in an antimicrobial resistance and characterization lab within the Infectious Disease Laboratory at the Centers for Disease Control and Prevention in Atlanta. According to a report released by the CDC on Friday, Sept. 9, 2016, a fourth U.S. case has been identified of a person infected with E. coli bacteria resistant to an antibiotic used as a last resort treatment. But the good news is none of these cases seems to be spreading to others. (AP Photo/David Goldman) (The Associated Press)

NEW YORK – Researchers are reporting that a fourth U.S. person has been diagnosed with bacteria resistant to a last resort antibiotic, but they are expressing some relief that these superbug precursors have not spread to others.

The latest case is a 2-year-old Connecticut girl who was diagnosed earlier this year, the Centers for Disease Control and Prevention reported Friday.

She and three other Americans have been found to have E. coli bacteria that were resistant to a last-resort medicine called colistin, and health experts worry that the trait could be passed to germs that already resist other antibiotics. Researchers last week reported a worrisome infection in a New Jersey man that could resist colistin and another important antibiotic.

The cases were treatable, however, and the infections did not appear to spread.