but the [[Centers for Disease Control and Prevention|CDC]] maintains that hand washing is generally more effective for the avoidance of illness.<ref>http://www.cdc.gov/handwashing/show-me-the-science-hand-sanitizer.html</ref>
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but the [[Centers for Disease Control and Prevention|CDC]] maintains that hand washing is generally more effective for the avoidance of illness.<ref>https://www.cdc.gov/handwashing/show-me-the-science-hand-sanitizer.html</ref>