Although healthcare workers are urged to wash their hands often and hand sanitizer dispensers are everywhere in hospitals, patients are less scrupulous and may be contributing to the spread of hospital-acquired infections, say Canadian researchers.

After tracking hundreds of patients in a transplant ward for nearly a year, the study team found that hand washing followed less than a third of bathroom visits, and washing or hand-sanitizer use happened only rarely after patients entered or left a room.

“We know that certain infections can be spread on people’s hands, and hand washing is an important way to prevent those infections,” said the study’s lead author, Dr. Jocelyn Srigley, associate medical director of infection prevention and control at Hamilton Health Sciences in Hamilton, Ontario.

One in 25 hospital patients has at least one infection contracted at the hospital at any given time, according to the U.S. Centers for Disease Control and Prevention. The CDC estimates there were 722,000 cases of hospital-acquired infection in 2011, many of them serious or even life-threatening.

The role of healthcare workers in transferring infectious microbes from place to place and person to person in hospitals has been well-studied, and staff are trained to take measures to avoid spreading infections.

But just two previous studies have looked at the potential for patients to spread infections in hospitals, to others and themselves, Srigley and her colleagues write in the journal Infection Control and Hospital Epidemiology.

The Canadian study team tracked 279 adult patients in a multiorgan transplant ward using tags attached to hospital ID bracelets that sent out ultrasound signals. Wireless receivers were installed throughout the ward to pick up the signals and track each patient’s location. The system also detected every time a soap or hand sanitizer dispenser was used.

They found that patients washed their hands about 30 percent of the time during bathroom visits, 40 percent of the time during mealtimes, 3 percent of the time while using kitchens on the wards, 3 percent of the time when entering their own rooms and 7 percent when exiting their room.

Women washed their hands more often than men, and were more likely than men to use soap when they did. All patients were more likely to wash their hands later in the day than in the morning.

Among 1,122 visits by 97 patients to the ward’s two kitchens, only 3 percent involved hand hygiene and less than one percent involved soap.

The researchers point to a previous study that found requiring patients to disinfect their hands four times a day significantly reduced the number of respiratory and gastrointestinal disease outbreaks in a psychiatric ward.

Srigley noted that the ultrasound observation system was not perfect and one limitation was that it, “didn’t know exactly what a patient was doing in the bathroom or when they were eating, so we don’t know for sure that a patient should have washed their hands at that time.”

In addition, “not all patients agreed to wear the system tags so we don’t know if the ones who wore the tags are reflective of all patients,“ Srigley said.

Despite these limitations, the new technology used in the study eliminated the problem of people changing their behavior when they know they’re being watched, said Dr. Yuen Kwok-yung, chair of Microbiology at the University of Hong Kong.

Kwok-yung told Reuters Health by email, “The findings will provide important data for the formulation of hand hygiene policy.”

Srigley feels that hospitals should encourage patients to wash their hands at certain times, but she is not yet sure what would be the most effective method.

Possibilities include “putting up posters, having someone talk to patients about hand washing, providing hand sanitizer or alcohol wipes at the bedside, etc.,” she said, adding that more research is necessary to determine the most effective method.

“The key message is that hand washing is an important way for people to protect themselves and prevent infections, whether they’re in the hospital, at home, at work, or anywhere else,” she said. “Especially with influenza season coming up soon, hand washing can help to keep us all healthy.”