Cold And Flu Viruses Require Frequent Disinfecting

Cold and flu viruses are usually transmitted when people touch a contaminated surface and then touch their face, mouth or eyes, which is why cleaning and disinfecting surfaces is so important. Pathogens are getting stronger and more resistant every year. Some can live for days and even weeks on surfaces and in the air, says Heidi Wilcox, owner of Wilcox EVS Solutions in Boston.

While cold viruses generally survive on indoor surfaces for up to seven days, flu viruses survive on hard surfaces for 24 hours. As a result, high-touch surfaces can be a constant source of contagion.

During cold and flu season, custodians at the University of Wisconsin take extra time to sanitize elevator buttons and doorknobs in common areas two to three times a day. If there is a confirmed case of flu, these precautions extend to the doorknobs and light switches in every resident room.

"Facilities should use a sanitizer and disinfectant daily on high-touch surfaces in and around the facility and in the restrooms to prepare for flu season," says Wilcox. "They should also focus on touch screens as these can sometimes be dirtier than toilets."

Indeed, restrooms are no longer the focal point when it comes to addressing contaminated surfaces. Gerba was surprised when his research revealed that lunch rooms and break rooms harbor more germs than restrooms.

"We've done tracer virus studies where we put [the virus] on a doorknob in a facility, and within four hours it's on about half the surfaces," he says. "But the hot spots seem to be the coffee break room or the lunch room. Apparently people spread gossip and germs in the same space."

Gerba suggests custodians wipe down tabletops and desktops more frequently than doorknobs and light switches because people touch these types of surfaces the most, quickly leading to recontamination. He also recommends equipping building occupants with disinfecting wipes to wipe down their desktops and tabletops throughout the workday.

"We've been impressed with how effective disinfecting wipes are," says Gerba. "Even if only half of the people use them, we can still cut down on the spread of viruses by 80 percent because they break the chain of transmission."

He believes the reason disinfecting wipes are so effective in combating colds and flu is because people wipe down a surface and then let it air dry. This allows the disinfectant to evaporate off the surface, thereby increasing its dwell time.

At the University of Wisconsin the housekeeping department supplies disinfecting wipes year-round to residents, student employees, health fellows and interns working in office areas.

"We have an expectation that they clean up after themselves, so we provide wipes for them to use at their workstations," says Krause.