Washington, September 22 : A new study has shown that the bacterium that causes a highly contagious and sometimes deadly form of diarrhoea is often carried by persons who do not have any of the disease symptoms.

The new findings, published online in Clinical Infectious Diseases, have dramatic implications for health care workers who treat and isolate only those patients who exhibit symptoms.

Clostridium difficile-associated disease (CDAD) is the most common health care-associated diarrhoeal disease in developed countries, with most infections occurring in hospitals, nursing homes, or other institutions.

Infection control measures—such as placing patients with suspected or documented CDAD under contact precautions until the diarrhoea resolved and disinfecting their rooms—have been effective in reducing, but not eliminating, CDAD outbreaks.

The new study offers understanding as to why the infection efforts have not been more successful. It suggests that the bacteria may be thriving on asymptomatic patients and items in their immediate vicinity such as call buttons, bed rails, bedside tables, and telephones.

The researchers found that spores were easily transferred from the patient’s skin to their hands.

“Our findings suggest that asymptomatic carriers of epidemic and non-epidemic C. difficile strains could contribute significantly to transmission in long-term care facilities. Simple modifications of current infection control practices, including glove use by health care workers and use of 10 percent bleach for room disinfection, could reduce the risk of transmission from asymptomatic carriers,” said senior author Dr. Curtis Donskey of the Louis Stokes Cleveland VA Medical Center.

Current guidelines recommend discontinuation of contact precautions for CDAD patients after diarrhoea resolves. But the researchers found during the study that about 25 per cent of the asymptomatic carriers were patients who had previously had had CDAD.

Based on their findings, the researchers propose extending the duration of contact precautions until the patient is discharged.

According to them, patients with a previous history of CDAD and antibiotic use in the prior three months were likely to be asymptomatic carriers, and patients with fecal incontinence were even more so. (With inputs from ANI)