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(Corrects headline, first and third paragraphs to show bacteriais resistant to last-resort antibiotic colistin, not allantibiotics)
By Ransdell Pierson and Bill Berkrot
May 26 (Reuters) - U.S. health officials on Thursdayreported the first case in the country of a patient with aninfection resistant to a last-resort antibiotic, and expressedgrave concern that the superbug could pose serious danger forroutine infections if it spreads.
"We risk being in a post-antibiotic world," said ThomasFrieden, director of the U.S. Centers for Disease Control andPrevention, referring to the urinary tract infection of a49-year-old Pennsylvania woman who had not travelled within theprior five months.
Frieden, speaking at a National Press Club luncheon inWashington, D.C., said the bacteria was resistant to colistin,an antibiotic that is reserved for use against "nightmarebacteria."
The infection was reported Thursday in a study appearing inAntimicrobial Agents and Chemotherapy, a publication of theAmerican Society for Microbiology. It said the superbug itselfhad first been infected with a tiny piece of DNA called aplasmid, which passed along a gene called mcr-1 that confersresistance to colistin.
"(This) heralds the emergence of truly pan-drug resistantbacteria," said the study, which was conducted by the WalterReed National Military Medical Center. "To the best of ourknowledge, this is the first report of mcr-1 in the USA."
The patient visited a clinic on April 26 with symptoms of aurinary tract infection, according to the study, which did notdescribe her current condition. Authors of the study could notimmediately be reached for comment.
The study said continued surveillance to determine the truefrequency of the gene in the United States is critical.
"It is dangerous and we would assume it can be spreadquickly, even in a hospital environment if it is not wellcontained," said Dr. Gail Cassell, a microbiologist and seniorlecturer at Harvard Medical School.
But she said the potential speed of its spread will not beknown until more is learned about how the Pennsylvania patientwas infected, and how present the colistin-resistant superbug isin the United States and globally.
"MEDICINE CABINET IS EMPTY FOR SOME"
In the United States, antibiotic resistance has been blamedfor at least 2 million illnesses and 23,000 deaths annually.
The mcr-1 gene was found last year in people and pigs inChina, raising alarm.
The potential for the superbug to spread from animals topeople is a major concern, Cassell said.
For now, Cassell said people can best protect themselvesfrom it and from other bacteria resistant to antibiotics bythoroughly washing their hands, washing fruits and vegetablesthoroughly and preparing foods appropriately.
Experts have warned since the 1990s that especially badsuperbugs could be on the horizon, but few drugmakers haveattempted to develop drugs against them.
Frieden said the need for new antibiotics is one of the moreurgent health problems, as bugs become more and more resistantto current treatments.
"The more we look at drug resistance, the more concerned weare," Frieden added. "The medicine cabinet is empty for somepatients. It is the end of the road for antibiotics unless weact urgently."
Overprescribing of antibiotics by physicians and inhospitals and their extensive use in food livestock havecontributed to the crisis.
More than half of all hospitalized patients will get anantibiotic at some point during their stay. But studies haveshown that 30 percent to 50 percent of antibiotics prescribed inhospitals are unnecessary or incorrect, contributing toantibiotic resistance.
Many drugmakers have been reluctant to spend the moneyneeded to develop new antibiotics, preferring to use theirresources on medicines for cancer and rare diseases that commandvery high prices and lead to much larger profits.
In January, dozens of drugmakers and diagnostic companies,including Pfizer, Merck & Co, Johnson & Johnson and GlaxoSmithKline, signed a declarationcalling for new incentives from governments to supportinvestment in development of medicines to fight drug-resistantsuperbugs. (Reporting by Ransdell Pierson; Additional reporting by BillBerkrot; Editing by Bernard Orr)
