John Boyce : Hands contaminated with virus often carry the flu . He says viruses can live for hours on various surfaces . Smith : People need to wash hands with soap and water for at least 15 seconds . He says water - based sanitizers can work in the absence of a sink .
John Boyce : Hands contaminated with virus often spread the flu . He says viruses can survive for hours on various surfaces . Boyce : People need to wash hands with soap and water for at least 15 seconds . He says alcohol-based sanitizers can work in the absence of a sink .