(Adds information from CDC news conference)
By Sharon Begley
NEW YORK, March 5 (Reuters) - "Nightmare bacteria" that have become increasingly resistant to even the strongest antibiotics infected patients in 3.9 percent of all U.S. hospitals in the first half of 2012, including 17.8 percent of specialty hospitals, public health officials said on Tuesday.
"Our strongest antibiotics don't work and patients are left with potentially untreatable infections," Dr Tom Frieden, director of the Centers for Disease Control and Prevention, said in a statement. He said doctors, hospitals and public health officials must work together to "stop these infections from spreading."
At a news conference, he added, "it's not often that our scientists come to me and say we have to sound the alarm, but that's what we are doing today."
Over the past decade more and more hospitalized patients have been incurably infected with the bugs, Carbapenem-Resistant Enterobacteriaceae (CRE), which kill up to half of patients who get bloodstream infections from them, according to a new CDC report. The report did not say how many patients were killed by the bacteria.
Enterobacteriaceae bacteria include more than 70 species that normally live in the water, soil and human digestive system, such as the well-known E. coli. Over the years, some Enterobacteriaceae have become resistant to all or almost all antibiotics, including last-resort drugs known as carbapenems. Present in one U.S. state in 2001, the superbugs have now spread to 42, Frieden said at the news conference.
Over the past decade, the proportion of Enterobacteriaceae that are resistant to the last-ditch antibiotics rose to 4.2 percent from 1.2 percent.
Almost all CRE infections occur in patients receiving medical care for serious conditions in hospitals, long-term acute-care facilities (such as those providing wound care or ventilation) or nursing homes.
CATHETERS OR VENTILATORS
These patients often have catheters or ventilators, which can allow bacteria "to get deeply into a patient's body," Frieden said. In addition, such seriously ill patients are often receiving antibiotics. When the antibiotics wipe out susceptible bacteria, the coast is clear for CRE to proliferate.
In one of the worst outbreaks, 18 patients at the National Institutes of Health Clinical Center in Bethesda, Maryland, contracted a CRE strain of Klebsiella pneumoniae in 2011. Seven patients, including a 16-year-old boy, died. The outbreak began when a patient unknowingly infected with CRE was transferred from a New York City hospital.
Northeastern states report the most cases of CRE, which "is prevalent in a number of hospitals in the New York area," said Dr Arjun Srinivasan, CDC's associate director for healthcare-associated infection prevention programs. He said patients and their families should ask a hospital or nursing home if it was monitoring for CRE and if it had any cases.
Only six states require healthcare providers to report cases of CRE to public health authorities.
Last month, CDC reported that unusual forms of CRE - with such exotic names as New Delhi Metallo-beta-lactamase and Verona Integron-mediated Metallo-beta-lactamase - are becoming more common in the United States. Of the 37 unusual forms ever identified, the last 15 have been reported since July.
The germs themselves spread from person to person, often on the hands of doctors, nurses and other healthcare professionals. They can easily pass their antibiotic resistance - contained in a speck of genetic material - to other kinds of germs, making additional kinds of bacteria potentially untreatable as well, CDC said.
That "can create additional life-threatening infections for patients in hospitals and potentially for otherwise healthy people," the CDC said in a statement.
The CDC is trying to make healthcare facilities more aware of the resistant germs, since their spread can be controlled with proper precautions and better practices. Israel, for instance, cut CRE infection rates in all 27 of its hospitals by more than 70 percent in one year.
Such measures include such standard infection control precautions as washing hands, as well as grouping patients with CRE together and dedicating staff, rooms and equipment to the care of patients with CRE alone, and using antibiotics sparingly. When an acute-care hospital in Florida had a yearlong CRE outbreak, implementing such measures cut the percentage of patients who got CRE to zero from 44 percent. (Editing by Doina Chiacu and Mohammad Zargham)