While infections with drug-resistant staph and \o7E. coli \f7have been grabbing headlines and public attention in recent months, a new bacterial threat has quietly emerged. Typically seen in elderly hospitalized patients, the illness has begun popping up in the community at large -- specifically among healthy younger people, including children and pregnant women.
The bacterium responsible, called \o7Clostridium difficile\f7, or \o7C. \f7\o7difficile\f7, has been blamed for recent outbreaks of intestinal infections in about 10 states, as well as Canada and Europe. Patients become ill with frequent bouts of watery diarrhea, fever and abdominal tenderness. In rare cases, the infection can progress to sepsis, colitis and even death.
"It's something that is usually acquired in the hospital. But now the concern is that there is a new epidemic strain that is seen outside the hospital," says Dr. Preeta Kutty, an investigator for the federal Centers for Disease Control and Prevention.
The strain, identified as NAP1, appears to be more virulent than its predecessor.
"There is a lot that is unknown, in particular, why we are seeing this shift from hospital cases to the community," says Dr. Judith O'Donnell, an associate professor of medicine at Drexel University College of Medicine in Philadelphia.
\o7C. difficile \f7is found in feces and is one of the leading causes of hospital-acquired diarrhea. People become infected by touching items or surfaces contaminated with the bacterium and then transmitting it to their mouths. It gains ground when patients take antibiotics -- often broad-spectrum antibiotics, such as clindamycin, penicillin and increasingly the class of drugs called fluoroquinolones. The drugs upset the balance of normal bacteria in the colon, killing good types of bacteria that protect the body.
In doing so, they allow \o7C. difficile \f7to flourish and begin releasing toxins that damage the intestines, says Dr. L. Clifford McDonald, a medical epidemiologist with the CDC who has studied \o7C. difficile \f7trends. Two primary toxins, toxin A and toxin B, cause the diarrhea and inflammation.
The pattern of \o7C. difficile \f7illness began to change in the late '90s, according to data from the CDC. Cases almost doubled between 1996 and 2003, the most recent year for which data are available, rising from 31 per 100,000 to 61 per 100,000.
