21 Oct 2009

Hospital workers spread germs

Hospital workers who see many patients may play a disproportionate role in spreading dangerous hospital-acquired infections, a new study finds.

These so-called peripatetic workers, such as radiologists or physical therapists, visit many patients in the course of a day, said Laura Temime, a researcher at the Conservatoire National des Arts et Metiers in Paris, and lead author of a study published in the Proceedings of the National Academy of Sciences.

"Although to my knowledge, an increased super-spreading potential of 'peripatetic' health-care workers has never really been formalised as a major hypothesis, there have been several reports of nosocomial outbreaks that have been traced back to such 'peripatetic' health-care workers," Temime said.

Nosocomial outbreaks
Her study adds to the evidence, she said. The study used a mathematical model of a hypothetical intensive care unit that was presumed free of the pathogen to see how easily hospital-based infections, such as methicillin-resistant Staphylococcus aureus (MRSA) spread.

Containing these outbreaks is of grave importance, public health officials agreed.

The study found infection rates increased by up to three times more when a peripatetic worker failed to wash his hands, compared to workers in the other groups.

The conclusions sound very logical, said Dr Zachary Rubin, an epidemiologist at Santa Monica-UCLA Medical Centre and Orthopaedic Hospital in Santa Monica. However, he added, "this is a mathematical model, and you have to do studies with human beings to see if the data is still true or not."

Temime said she and her colleagues are doing just that. They are involved in a European project called Mastering Hospital Antimicrobial Resistance (MOSAR), in which data on exposures and bacterial colonisation will be collected on patients and health-care workers. "We are planning to use this data to validate our model," Temime said.

Hand washing
For now, many hospitals are stepping up efforts to promote hand washing among employees. Because the peripatetic workers have "major super-spreading potential", the study authors recommend individual surveillance of these health-care workers.

Rubin said that hospitalised patients shouldn't be shy about asking the health-care workers who come in contact with them to follow infection control guidelines. Some hospitals have posted signs in patient rooms asking, "Did your health-care worker wash his hands?" to make patients more aware of the importance of hand washing, he said.

"If a patient is concerned [about lack of hygiene from a health-care worker], he can always talk to the head nurse or charge nurse," Rubin said, as well as the hospital's patient advocate or his own physician.

(Kathleen Doheny/HealthDay News, October 2009)