The toll of Clostridium difficile, or C-diff — a bacterium that causes a dangerous form of diarrhea and is the most common cause of hospital-acquired infections in the United States — is much higher than previously believed, according to a study published Wednesday by the Centers for Disease Control and Prevention (CDC).
Using data collected from 10 regions of the country — including the central Minnesota counties of Stearns, Benton, Todd and Morrison — the study found that C-diff caused about 453,000 infections in the United States in 2011. Health officials had previously linked the bacterium to an estimated 240,000 to 333,000 infections each year.
The new study also estimated that 29,000 people died within 30 days of being diagnosed with C-diff in 2011. Of those deaths, about 15,000 were “directly attributable” to the infection.
More than 80 percent of all the deaths associated with C-diff in the study were among people aged 65 years or older.
These findings are troubling. C-diff can be very difficult to treat, mainly because strains of the bacterium have become resistant to standard antibiotics. To get rid of the infection, patients often have to have part of their colon removed. Even then, the disease frequently recurs — in 20 percent of patients, according to the new study.
Many C-diff infections could have been prevented with more appropriate use of antibiotics in both hospitals and other health-care settings, CDC officials note. Previous studies have suggested that 30 to 50 percent of antibiotics prescribed in U.S. hospitals are unnecessary or incorrect. The overuse and misuse of antibiotics contribute to C-diff illnesses by altering or killing off beneficial bacteria in the intestines that help protect against the C-diff bacterium. This suppression of beneficial bacteria can last for weeks or months, leaving people vulnerable to picking up the infection from contaminated surfaces long after they have stopped taking the antibiotics — and left the hospital.
Higher rates in Minnesota
C-diff infections have been increasingly diagnosed outside of hospitals, particularly in nursing homes but also in other “community” settings. This new CDC study found that more than 345,000 of the 2011 C-diff infections occurred in non-hospitals settings, including 100,000 in nursing homes.
The Minnesota counties included in the study had a significantly higher rate of community-associated C-diff infections — 123 per 100,000 persons — than the other sites. Indeed, the combined rate for all 10 sites in the study was 48 per 100,000 persons.
In a released statement, Dr. Stacy Holzbauer, an epidemiologist at the Minnesota Department of Health (MDH) and a co-author of the study, said Minnesota’s higher rate was the result of a more sensitive method of testing for the disease and the fact that the four counties were more rural than the other sites in the study. Studies conducted elsewhere in the world, she pointed out, have also demonstrated higher rates of community-associated infections in rural areas.
What patients can do
The CDC has made the prevention of C-diff infections a high priority, but getting health-care providers to prescribe and use antibiotics more appropriately has been a challenge. In addition, many health-care facilities do a less than stellar job of quickly identifying and isolating patients with C-diff infections and of notifying other facilities of such infections when patients are transferred.
The rest of us need to take some responsibility, however, and not demand antibiotics when our health-care providers say they are unnecessary.
In addition, CDC officials recommend the following preventive actions for patients:
- Take antibiotics only as prescribed by your doctor and be sure to complete the entire prescribed course of treatment. (In other words, finish taking all the drugs even if you feel better.)
- Tell your doctor if you develop diarrhea after taking antibiotics, even if it’s a few weeks later.
- Always wash your hands before eating and after using a bathroom.
- If you or someone in your family has diarrhea, try to use a separate bathroom, or be sure the bathroom is cleaned well each time someone with diarrhea has used it.
The CDC study was published in the New England Journal of Medicine.