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ScienceShot: How Clean Is Your Hotel Room?

When you've collapsed in a comfortable hotel bed at the end of a full day of vacationing, the last thing you want to worry about is whether or not a previous guest left germs behind. But germs are invisible to the naked eye, so how do hotel housekeepers—who have an average of 30 minutes to clean a room—make sure their job is well done? In Texas, Indiana, and South Carolina, researchers tested levels of bacteria on 162 surfaces in nine hotel rooms after they'd been cleaned. While door handles, showers, and carpets had been mostly scoured of germs, objects including light switches, remotes, bathroom sinks, and telephone keypads still had high levels of bacteria. And the worst offenders: mops, sponges, and gloves on the housekeeper's cleaning cart. Rather than send a scare message to hotel-goers, the researchers hope the data, presented today at the 2012 General Meeting of the American Society for Microbiology in San Francisco, will help housekeeping managers optimize their cleaning procedures. Housekeepers could be encouraged to spend more time on the items found to remain contaminated after cleaning, for example. Hotels could then retest rooms at random to check whether the alternate cleaning measures are working out. Until then, sleep tight.

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