Your hands do all sorts of things for you. They write, use electronic devices, handle money, prepare meals, dress wounds, etc. Your hands gather bacteria with each job they do. We have all heard about the importance of hand washing to remove bacteria. Although studies have reported the importance of thorough hand drying after washing, the role of hand drying has not been widely promoted, and its relevance to hand hygiene and infection control seems to have been overlooked. Yet according to the Mayo Clinic (August 2012), the transmission of bacteria is more likely to occur from wet skin than from dry skin, making proper hand drying an essential component of hand hygiene procedures.
Wash & Rinse…
In actual practice, hand washing can vary considerably from a brief rinse of the hands to extensive scrubbing. With most handwashing regimens, the numbers of bacteria on the skin surface are lowered, but not eliminated. A key point seems to be how long you actually spend spreading the soap over your hands; for example, the special chemicals in antibacterial soaps take time to kill the microbes. Thus, if you rinse your hands almost immediately after applying the soap, you will not get the full benefit of the product. The U.S. Center for Disease Control and Prevention recommends washing hands for at least 20 seconds to allow enough time to remove and rinse off germs. However, ” In How Should Hands be Washed?” Dr Anna Snelling of the Royal Society for Public Health states that many people take less than 10 seconds for the whole process of washing and rinsing.
…Then Dry!
Another factor that appears to greatly influence bacterial transfer and dissemination is the degree of wetness of hands. This is, in part, because of the physical aspects of moisture droplets that transfer bacteria from one surface to another, but also because wet, the bacteria may be maintained in a physiological state better suited to survive in/on the new environment. When samples of skin, food, and utilities were touched with wet, undried hands, microbial counts of 68,000, 31,000 and 1,900 respectively were found on these surfaces, yet these numbers decrease progressively as hands dry, according to a study published in Epidemiol Infect (1997). Many other studies have shown similar results. Coates et al reported that washing hands with either soap and water or water alone—combined with towel drying—can effectively remove bacteria from the hands. Meanwhile, Infection Control Today (2010) cited studies showing that some bacteria are likely to remain if hands are only shaken dry—or wiped on clothes—after washing.
Hand drying is even recognized as an essential part of handwashing procedures aimed at reducing the spread of methicillin-resistant Staphylococcus aureus—or MRSA—in hospitals (Collins and Hampton 2005).
The fact is bacteria from a great variety of sources can survive on our hands and can be easily transferred to other surfaces, increasing the risk of cross-contamination. When hands are washed, the number of bacteria on the surface of the skin decreases, but they are not necessarily eliminated.
Despite all these findings, few protocols stipulate exactly how to dry the hands or for how long. What these studies do prove, however, is that if the hands are still damp, bacteria are more readily transferred to other surfaces, which means drying hands thoroughly is a very important part of the process of maintaining a healthy environment.
