An emerging superbug is infecting an increasing number of people in the United States, and health officials are calling for urgent action to stop its spread.

During the first six months of 2012, nearly 200 hospitals and long-term acute care facilities together treated at least one person who had been infected by the superbug, known as Carbapenem-Resistant Enterobacteriaceae, or CRE, according to a new report from the Centers for Disease Control and Prevention (CDC). The bacteria is resistant to a class of antibiotics known as carbapenem, powerful drugs that are typically used as a last resort to treat resistant bacterial infections, thus the origin of the superbug’s name.

CRE can cause pneumonia and blood and urinary tract infections. CRE infections are still rare, and so far, nearly all cases have been seen in people who’ve had long-term care in hospitals, nursing homes or other healthcare facilities. But once a person becomes ill, the disease can be lethal, killing up to half of people who develop serious infections, the CDC said.

“CRE are nightmare bacteria. Our strongest antibiotics don’t work and patients are left with potentially untreatable infections,” said Dr. Tom Frieden, director of the CDC. Doctors, hospitals and public health officials must work together to implement strategies to stop CRE’s spread,  Frieden said.

Enterobacteriaceae are a family of bacteria that include E. coli and Klebsiella pneumoniae, and typically live in the digestive tract, but can cause infections if they spread outside the gut, the CDC said. Over time, some of these bacteria have developed resistance to carbapenems.

CRE were first identified in the U.S. in 2001, and have now spread to 42 states. The new report, which examined U.S. health care infections, found that the percentage of Enterobacteriaceae that are resistant to carbapenems has increased fourfold during the last decade.

In 2012, 4.6 percent of hospitals and 18 percent of long-term acute care facilities, reported having a patient with a CRE infection, the CDC report said.

Healthy people don’t usually develop CRE infections. People most at risk for infection are those whose care requires devices such as a ventilator or catheter, and who require a long course of antibiotics, the CDC said.

Hospital workers who don’t properly wash their hands can spread the bacteria between patients, and the bacteria themselves can spread resistance to other similar bacteria.

Unlike methicillin-resistant Staphylococcus aureus (MRSA), CRE hasn’t spread into the community, Frieden said.

“That’s really a message of hope: we still have a window of opportunity to stop it” before it becomes as prevalent as other antibiotic-resistant organisms like MRSA, Frieden said.

In 2012, the CDC created guidelines for preventing CRE infections in hospitals and other care facilities. These include following proper hand hygiene recommendations (hand-washing); grouping patients together who have CRE; dedicating certain staff members and equipment to people who have CRE; knowing which patients in a hospital have CRE and alerting other health care facilities about the infection if the patient is transferred; and using antibiotics wisely.

Facilities that have implemented these measures have seen a drop in their CRE infection rates, Frieden said.

Patients can also play a role in prevention. For instance, if they have a catheter put in, they can ask how long it will be in place, and ask that it be removed as soon as possible, Frieden said.

Continued research into tests to detect CRE, and ways to treat it, is critical as well, Frieden said. The report will be published this week in the CDC’s Morbidity and Mortality Weekly Report.

Pass it on: Urgent action is needed to prevent the spread of CRE infections, which are resistant to most antibiotics.

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