Your mother was right — don’t forget to wash your hands, and use plenty of soap and water. It works just as well as antimicrobial products in removing bacteria, and still works best against viruses, including those that cause the common cold, according to the largest, most comprehensive study of hand hygiene products to date.
The study, led by Emily Sickbert-Bennett, a public-health epidemiologist with the UNC Health Care System and the School of Public Health, was designed to test how well various products work to prevent infection in hospitals and other health-care settings. Sickbert-Bennett conducted the study for her master’s thesis.
The researchers tested twelve hand-sanitizing products that contained active ingredients similar to products sold at most drug and grocery stores. Participants’ hands were infected with bacteria or harmless viruses, then the participants washed or sanitized their hands for just ten seconds. In similar studies, subjects have cleaned their hands for the recommended time of thirty seconds, but the shorter time is more realistic, especially for busy health-care workers, Sickbert-Bennett says.
After just one contamination with bacteria and one washing, all the products except two worked well, removing 90 to 99 percent of the bacteria on hands. The products that did significantly worse were two kinds of moist antimicrobial towelettes.
Soaps used at the sink with water were most effective against bacteria. In just one washing, it didn’t matter whether the soap contained antimicrobial agents or not — both methods worked about the same.
With viruses, which are hard to kill with these products, nothing worked better than physically removing them with plain soap and water. The alcohol-based hand rubs were generally ineffective in reducing the amount of virus on the hands.
The study shows that some products were more effective than others, but that doesn’t mean that the less effective products don’t help at all, Sickbert-Bennett says. “Even the products that didn’t work as well may have removed enough organisms from the hands to prevent illness,” she says.
