Oct. 28 (Bloomberg) -- Hospital workers cost their institutions $1.98, on average, each time they fail to wash their hands before seeing a patient, a study found.

The expense totals $1.77 million a year at a 200-bed institution and comes from treating methicillin resistant staphylococcus aureus, or MRSA, one of the most dangerous infections in hospitals, said the lead author, Keith Cummings, a fourth-year student at Duke University School of Medicine in Durham, North Carolina, in a report released today.

An estimated 94,360 people in the U.S. developed a MRSA infection in 2005, according to the Centers for Disease Control and Prevention's Web site. About 85 percent of the infections were associated with health care, according to a study cited by the agency. MRSA is transmitted by skin-to-skin contact, and can be prevented by hand washing. Of the cases associated with health care, 27 percent were hospital-based.

``My objective was to give some data that would be an incentive for hospitals to undertake more comprehensive hand- hygiene compliance,'' Cummings said in a telephone interview. ``And by increasing consciousness of what it costs when someone doesn't wash their hands, maybe we can change workers' attitudes.''

Hand washing now occurs about 55 percent of the time, and each increase of 1 percentage point would save a hospital $39,000 a year, Cummings said.

Cummings made the estimate by using published data on MRSA- transmission, as well as national figures on hand washing. Using the Duke hospital's average length of stay, and the number of visits to a user's room each day, the researchers estimated how often a patient might be infected.

Close Encounters

A patient who stayed in a hospital for 6.2 days would have eight encounters with a health-care worker who had seen a MRSA- positive patient and hadn't washed his hands, according to the study.

``These are all probabilities,'' Cummings said. ``Given that we're able to calculate the number of incidents, and we know the rate of transmission, we can calculate the possibility of transmitting MRSA in a single episode.''

After finding that probability, the researchers, who included Keith Kaye and Deverick J. Anderson, calculated a cost for the MRSA cases.

The expense of treating the MRSA worked out to $1.98 for each instance that a worker hadn't washed his or her hands, according to the research, which was presented at the Interscience Conference on Antimicrobial Agents and Chemotherapy, in Washington.

Health-care workers are expected to decontaminate their hands before having direct contact with patients and before donning sterile gloves to insert catheters, among other specific situations listed in guidelines, according to the CDC, a federal agency based in Atlanta.

To contact the reporter on this story: Elizabeth Lopatto in New York at elopatto@bloomberg.net.

Last Updated: October 28, 2008 12:15 EDT