The largest, most comprehensive study ever done comparing the effectiveness of hand hygiene products shows that nothing works better in getting rid of disease-causing viruses than simply washing one's hands with good old-fashioned soap and water.

Among the viruses soapy hand washing flushes down the drain is the one that causes the common cold. Other removable viruses cause hepatitis A, acute gastroenteritis and a host of other illnesses.

A separate key finding was that waterless handwipes only removed roughly 50 percent of bacteria from volunteer subjects' hands. Anti-microbial agents were best at reducing bacteria on hands, but waterless, alcohol-based agents had variable and sometimes poor effects, becoming less effective after multiple washes, Sickbert-Bennett said. For removing viruses from the hands, physical removal with soap and water was most effective since some viruses are hardy and relatively resistant to disinfection.

Authors: Drs. William A. Rutala and David J. Weber, professors of medicine and epidemiology at the UNC schools of medicine and public health; Dr. Mark D. Sobsey, professor of environmental sciences and engineering in public health; and medical technologist Maria F. Gergen-Teague. Dr. Gregory P. Samsa, a Duke University biostatistician - American Journal of Infection Control.