NIH Superbug Outbreak Serves as Warning

Oct. 07--Much of Johns Hopkins epidemiologist Jason Farley's recent research has focused on an evolving medical crisis: How to stop the spread of bacteria that have adapted immunity to most antibiotics.

To stop it the medical community needs to track it. He's found that men recently arrested in Baltimore as well as Hopkins psychiatric patients were far more likely than the general population to be carriers of MRSA, the increasingly common bacteria resistant to many drugs. Now, he's launching a study exploring eradication of MRSA in HIV-positive patients, who, like others with compromised immune systems, are more likely to contract drug-resistant bacterial infections.

One category of drug-resistant bacteria, a strain of which killed a seventh person at the National Institutes of Health Clinical Center in Bethesda last month, has been found on patients at nearly all Maryland hospitals, state health officials said. Health care providers say they are on constant guard for potential infections from such so-called superbugs.

But researchers wonder whether current precautions are enough to outsmart the deadly creatures. Even following CDC guidelines -- and in the case of the NIH center, going as far beyond them as ripping out plumbing found to contain dangerous bacteria -- is not foolproof.

"We continue to discover changing epidemiology," said Farley, an assistant professor at the Johns Hopkins University School of Nursing. "We've identified newer, stronger antimicrobial agents. But every time we think we get a handle on that bacteria, the bacteria show us who's in charge."

It's proved hard to eradicate at the NIH hospital, considered the federal government's top medical research facility. Eighteen people were infected with drug-resistant bacteria Klebsiella pneumoniae there in 2011, and six of them died as a direct result, according to research published in August. A seventh, who was the first to be infected with the bacteria since January, died Sept. 7.

About 80 percent of Maryland acute care hospitals surveyed by the state had at least one patient either carrying or infected with what are known as carbapenem-resistant Enterobacteriaceae, a category of drug-resistant bacteria found normally in the intestines that includes the bacteria found in the NIH cases. That's from a snapshot survey of 36 of the 46 state hospitals conducted by health officials last year.

Eradicating the bacteria is difficult because of their evolving nature. Overuse of common antibiotics in people who are chronically ill has created a larger public health issue, epidemiologists said. The bacteria have adapted to be less vulnerable to the antibiotics. Part of the solution lies in more judicious use of antibiotics.

"I grew up thinking antibiotics were going to cure everything, and we're losing them," said Dr. Trish Perl, senior epidemiologist for Johns Hopkins Health System.

The full extent of people infected with or carrying drug-resistant bacteria in Maryland can't be known because hospitals aren't required to report cases involving many types of bacteria. Every case of about 63 diseases, including bacterial meningitis, tuberculosis and some sexually transmitted diseases, must be reported to state health officials; others, like the flu, are reported in aggregate.

To treat superbug infections, health care workers can use some rarer and older types of antibiotics.

Researchers are looking to find new, better ways to fight superbugs. While testing and studies can tell doctors nearly everything they need to know about how to treat a patient with a heart condition, less is known about tackling superbug infections, said Dr. Anthony Harris, a professor of epidemiology, public health and medicine at the University of Maryland School of Medicine.

"In infection control, we're unfortunately not at [the same] level of science," Harris said.

The university is taking part in research exploring whether requiring health care workers to wear gloves and gowns for all contact with intensive care unit patients leads to fewer infections of Methicillin-resistant Staphylococcus aureus, or MRSA, Harris said.

At Hopkins, Farley is launching a study in October exploring whether MRSA eradication among people who are HIV positive should focus on the person's entire household, and not just the individual. One previous study he conducted found that inmates in the Baltimore correctional system had about a 16 percent chance of being carriers for MRSA, compared with 1 percent for the general population. Another study found similar results among patients at Hopkins psychiatric clinics, he said.

Despite the continued outbreak in Bethesda, officials at Baltimore-area hospitals said they have not changed their infection control practices.

The typical response involves isolating patients who are carrying or infected with the bacteria, thorough scrubbing and disinfection of surfaces and requiring extra protective gloves and gowns of hospital staff working closely with the patients who are either infected or carriers. MRSA in particular is a common cause of hospital-borne infections, though it increasingly comes from outside the hospital.

At NIH, efforts to stop the spread of the Klebsiella bacteria, also known as KPC, went even further. In addition to ripping out and replacing plumbing in hospital sinks, NIH officials ordered the gene sequencing of the bacteria found in each patient to learn how it may have spread.

NIH officials said in a statement they are taking "strong action to keep KPC from spreading further," including ongoing testing for the bacteria in patients and hospital surfaces and "redoubling" efforts to isolate and decontaminate. They declined to comment beyond that.

Hospital leaders said the bacteria's resilience is an important lesson, although the type present at NIH is less common than other drug-resistant bacterium varieties like MRSA.

At University of Maryland Medical Center, where many of the state's sickest patients are sent, about 5 percent to 10 percent of admitted patients test positive for some type of drug-resistant bacteria, said Dr. Jonathan Gottlieb, the center's chief medical officer. A small percentage of people unknowingly carry bacteria like MRSA but don't develop infections or symptoms unless their immune system is compromised by an illness.

At Johns Hopkins Hospital's institutions, the bacteria also are becoming increasingly common, in some cases coming via patients who are airlifted from other parts of the world, Perl said.

Superbug cases have appeared even at community hospitals, particularly along the Interstate 95 corridor in the Northeast. MedStar Union Memorial Hospital sees about two patients a year who carry drug-resistant bacteria, and the rate is likely similar at other hospitals, said Dr. Phil Buescher, director of intensive care at the Charles Village hospital.

At hospitals without the sophisticated lab equipment needed to identify many types of bacteria, though, it can be difficult to confirm cases in the first place, Perl said.

Hospital leaders emphasized that the public should better understand that in general, bacteria are necessary in our bodies. Buescher blamed television reports raising concerns over drug-resistant bacteria found in public places, saying they exaggerate the dangers.

"If you leave your milk out until tomorrow, it goes rotten but that's because it had bacteria in it to start with," Buescher said. "Your kid is drinking bacteria."

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