Pa. woman with antibiotic-resistant bacteria didn't spread it, CDC says
Federal health investigators said Friday that a Pennsylvania woman infected with an antibiotic-resistant bacteria does not appear to have spread it to anyone else.
The woman, whose hometown was not revealed, contracted bacteria with an antibiotic-resistant gene known as MCR-1 and has recovered, the Centers for Disease Control and Prevention said in a report.
The MCR-1 gene gives bacteria carrying it resistance to a drug called colistin, which is used as a last resort for difficult-to-treat infections.
On Friday, the CDC, in a separate report, said another superbug surfaced in a 2-year-old girl in Connecticut, who traveled to the Caribbean over the summer. She got sick in June and was found to have the MCR-1 gene in her system. CDC doctors said they suspect her case was foodborne and she has since recovered.
Dr. Amesh Adalja, an infectious disease specialist senior associate at the UPMC Center for Health Security, said more cases of MCR-1 detection should be expected.
“Antibiotic resistance is a worldwide phenomenon, and there is no reason to not expect this colistin resistance mechanism to spread any differently,” he said.
Investigators said they still don't know how the Pennsylvania woman picked up the superbug. She had no international travel for one year, no exposure to livestock and a “limited role in meal preparation with store-bought groceries,” the CDC found. But she visited four medical facilities and was housed in two of them for more than a week.
The gene is carried on a mobile piece of DNA, or plasmid, meaning it could move from one bacterium to another, spreading antibiotic resistance between bacterial species.
The woman marked the first detected United States case in May. She was being treated for a possible urinary tract infection when doctors discovered the gene. The CDC and the Pennsylvania Department of Health investigated her friends, family and contacts and the medical facilities where she was treated.
“No bacteria with the MCR-1 gene were detected among the 105 persons screened,” the CDC wrote in its report. “These findings suggest that the risk for transmission from a colonized patient to otherwise healthy persons, including persons with substantial exposure to the patient, might be relatively low.”
Ben Schmitt is a Tribune-Review staff writer. Reach him at firstname.lastname@example.org.