A superbug resistant to every antibiotic available in the U.S. medical arsenal killed a Nevada woman last summer, the Centers for Disease Control and Prevention reported Thursday.

The woman, who was in her 70s and had a two-year history of hospitalizations in India, was hospitalized in Reno for a carbapenem-resistant Enterobacteriaceae (CRE) infection. Investigators identified the specific microbe as Klebsiella pneumoniae, which usually causes urinary tract infections.

The woman had returned to the United States in early August from an extended visit to India and was admitted to a hospital Aug. 18 with a diagnosis of systemic inflammatory response syndrome resulting from an infection in her right hip seroma, the CDC said in its Morbidity and Mortality Weekly Report.

The woman developed septic shock and died in early September.

CDC investigators found the Klebsiella pneumoniae, which the woman contracted in India, totally resistant to 26 antibiotics, including all aminoglycosides and polymyxins, and intermediately resistant to tigecycline (a tetracycline derivative).

The investigators said the superbug was controlled by an intravenous formulation of fosfomycin , but such solutions are not approved for use in the United States.

“It was tested against everything that’s available in the United States … and was not effective,” Dr. Alexander Kallen, one of the report’s authors told Stat.

“I think it’s concerning. We have relied for so long on just newer and newer antibiotics. But obviously the bugs can often [develop resistance] faster than we can make new ones.”

Dr. James Johnson, a professor of infectious diseases medicine at the University of Minnesota and a specialist at the Minnesota VA Medical Center, called the death “the harbinger of future badness to come.”

The CDC said CREs resistant to all antimicrobials “are very uncommon,” with 80 percent susceptible to at least one aminoglycoside and nearly 90 percent susceptible to tigecycline.

The CDC said doctors and hospitals should routinely determine whether patients had been overseas and whether they were hospitalized.

CREs commonly live in the gut and are resistant to carbapenems, a drug normally used when other antibiotics have failed.

Modern Farmer reported last week CRE has been found on a pig farm in the United States for the first time, raising the specter of a massive infection in the pig population and possible interspecies transfer of the drug-resistant gene from pigs to humans through fresh meat.