New Study Details Burden of C. Diff in U.S.

Mar. 1, 2015
Inappropriate Use of Antibiotics Biggest Risk Factor for Infection
Clostridium difficile

A new study led by scientists at the Centers for Disease Control and Prevention, with support and data from researchers at the University of Rochester Medical Center, estimates that Clostridium difficile or C. diff caused almost half a million infections in the United States in 2011.

C. diff, a bacterial infection that can cause life-threatening diarrhea, is most often associated with hospitals. But, this latest analysis estimates that only a quarter of health care-associated cases (cases in which an individual had some interaction with a health care facility) occurred in the hospital, suggesting that the majority arose in other settings, such as nursing homes or following a doctor’s visit.

Study author Ghinwa Dumyati, M.D., director of the communicable diseases surveillance and prevention program at URMC’s Center for Community Health, says that taking antibiotics is the most important risk factor for developing C. diff. Antibiotics are life-saving medications, but, in the process of wiping out disease-causing bacteria, they also eliminate beneficial bacteria that are normally present in the gut and protect against infection. This gives organisms like C. diff an open playing field to replicate.

“If we are going to prevent this infection we have to take a broad approach by targeting antibiotic use in the hospital, in long-term care facilities and in doctor’s offices and other outpatient care settings,” said Dumyati, an associate professor and infectious diseases physician who treats patients at UR Medicine’s Strong Memorial Hospital. “Though a vaccine is in development and fecal transplants are showing some promise in treating C. diff infection, we can’t wait for these to come to fruition; we need to address the problem now and the best way to do that is by improving the appropriate use of antibiotics.”

Dumyati is leading the charge in Rochester on multiple fronts. She heads the Rochester Patient Safety Collaborative, a citywide effort that has reduced the incidence of C. diff in area hospitals by almost 30 percent through improved infection control, environmental cleaning and an antimicrobial stewardship program to limit the use of a group of antibiotics that predisposes patients to C. diff infection. With a grant from New York State, she is also targeting C. diff in nursing homes by improving antibiotic use, focusing on the overuse of antibiotics for urinary tract infections.

The new study, which was published in the New England Journal of Medicine, is the largest U.S. population-based survey of C. diff infections to date. The CDC collected data from 10 diverse geographic locations in the United States, including Rochester. Dumyati’s team fed data to the CDC through the New York State Emerging Infections Program, which is part of a CDC-funded network that keeps hawk-like watch on the activity of several infectious diseases of public health importance. Scientists estimated that C. diff caused approximately 453,000 infections and was associated with approximately 29,000 deaths in the United States in 2011. They also found that the infection was more likely to occur in females, whites and people 65 years old or older.

This national estimate is higher than previous U.S. estimates, but study authors say comparisons are difficult because different surveillance methods, more sensitive testing and updated definitions of C. diff were used in the new analysis. Prevention remains a national priority, and over the next five years the CDC, in collaboration with partners in health care, public health, academia and others, will work to combat C. diff and antibiotic resistance as part of the National Strategy to Combat Antibiotic Resistant Bacteria.

Dumyati says that patients can help to prevent C. diff infections by taking antibiotics only as prescribed by their doctor and completing the prescribed course of treatment. Understanding that an antibiotic is not recommended in many cases, such as for most sore throats, colds and the flu that are caused by viruses, is also important. Dumyati encourages patients to tell their doctor if they have been on antibiotics and get diarrhea and to wash their hands before eating and after using the bathroom, as well.