Hospital workers who deal directly with patients wash their hands less frequently as their workday progresses, says a study.
This decline in compliance with hand washing rules goes up with increase in work pressure, the findings showed.
"For hospital caregivers, hand-washing may be viewed as a lower-priority task and thus it appears compliance with hand hygiene guidelines suffers as the workday progresses," said Hengchen Dai from the University of Pennsylvania in the US.
"Demanding jobs have the potential to energise employees, but the pressure may make them focus more on maintaining performance on their primary tasks (patient assessment, medication distribution), particularly when they are fatigued," Dai added.
The researchers looked at three years of hand-washing data from 4,157 caregivers in 35 US hospitals.
They found that "hand-washing compliance rates" dropped by an average of 8.7 percentage points from the beginning to the end of a typical 12-hour shift.
The decline in compliance was magnified by increased work intensity.
So the demands of the job could deplete the mental reserves they need to follow rules.
"Just as the repeated exercise of muscles leads to physical fatigue, repeated use of executive resources (cognitive resources that allow people to control their behaviour, desires and emotions) produces a decline in an individual's self-regulatory capacity," the researchers concluded.
More time off between shifts appeared to restore workers' executive resources - they followed hand-washing protocol more carefully after longer breaks.
Hand-washing in hospitals has been demonstrated to reduce infections and save money.
The study appeared in the American Psychological Association.
