(Reuters) - U.S. health officials on Thursday reported the first
case in the country of a patient with an infection resistant to all
known antibiotics, and expressed grave concern that the superbug could
pose serious danger for routine infections if it spreads.
"We risk being in a post-antibiotic world," said
Thomas Frieden, director of the U.S. Centers for Disease Control and
Prevention, referring to the urinary tract infection of a 49-year-old
Pennsylvania woman who had not travelled within the prior five months.
Frieden, speaking at a National Press Club luncheon
in Washington, D.C., said the infection was not controlled even by
colistin, an antibiotic that is reserved for use against "nightmare
The infection was reported Thursday in a study
appearing in Antimicrobial Agents and Chemotherapy, a publication of the
American Society for Microbiology. It said the superbug itself had
first been infected with a tiny piece of DNA called a plasmid, which
passed along a gene called mcr-1 that confers resistance to colistin.
"(This) heralds the emergence of truly pan-drug
resistant bacteria," said the study, which was conducted by the Walter
Reed National Military Medical Center. "To the best of our knowledge,
this is the first report of mcr-1 in the USA."
The patient visited a clinic on April 26 with
symptoms of a urinary tract infection, according to the study, which did
not describe her current condition. Authors of the study could not
immediately be reached for comment.
The study said continued surveillance to determine the true frequency of the gene in the United States is critical.
"It is dangerous and we would assume it can be
spread quickly, even in a hospital environment if it is not well
contained," said Dr. Gail Cassell, a microbiologist and senior lecturer
at Harvard Medical School.
But she said the potential speed of its spread will
not be known until more is learned about how the Pennsylvania patient
was infected, and how present the colistin-resistant superbug is in the
United States and globally.
"MEDICINE CABINET IS EMPTY FOR SOME"
In the United States, antibiotic resistance has been blamed for at least 2 million illnesses and 23,000 deaths annually.
The mcr-1 gene was found last year in people and pigs in China, raising alarm.
The potential for the superbug to spread from animals to people is a major concern, Cassell said.
For now, Cassell said people can best protect
themselves from it and from other bacteria resistant to antibiotics by
thoroughly washing their hands, washing fruits and vegetables thoroughly
and preparing foods appropriately.
Experts have warned since the 1990s that
especially bad superbugs could be on the horizon, but few drugmakers
have attempted to develop drugs against them.
Frieden said the need for new antibiotics is
one of the more urgent health problems, as bugs become more and more
resistant to current treatments. "The more we look at drug resistance,
the more concerned we are," Frieden added. "The medicine cabinet is
empty for some patients. It is the end of the road for antibiotics
unless we act urgently."
Overprescribing of antibiotics by physicians
and in hospitals and their extensive use in food livestock have
contributed to the crisis. More than half of all hospitalized patients
will get an antibiotic at some point during their stay. But studies have
shown that 30 percent to 50 percent of antibiotics prescribed in
hospitals are unnecessary or incorrect, contributing to antibiotic
Many drugmakers have been reluctant to spend
the money needed to develop new antibiotics, preferring to use their
resources on medicines for cancer and rare diseases that command very
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 declaration calling for new
incentives from governments to support investment in development of
medicines to fight drug-resistant superbugs.
(Reporting by Ransdell Pierson; Additional reporting by Bill Berkrot; Editing by Bernard Orr)