Reducing viral contamination from finger pads: handwashing is more effective than alcohol-based hand disinfectants

Background: Hand hygiene is important for interrupting transmission of viruses through hands. Effectiveness of alcohol-based hand disinfectant has been shown for bacteria but their effectiveness in reducing transmission of viruses is ambiguous. Aim: To test efficacy of alcohol hand disinfectant against human enteric and respiratory viruses and to compare efficacy of an alcohol-based hand disinfectant and handwashing with soap and water against norovirus. Methods: Efficacies of a propanol and an ethanol-based hand disinfectant against human enteric and respiratory viruses were tested in carrier tests. Efficacy of an alcohol-based hand disinfectant and handwashing with soap and water against noroviruses GI. 4, GII. 4, and MNV1 were tested using finger pad tests. Findings: The alcohol-based hand disinfectant reduced the infectivity of rotavirus and influenza A virus completely within 30 s whereas poliovirus Sabin 1, adenovirus type 5, parechovirus 1, and MNV1 infectivity were reduced <3 log(10) within 3 min. MNV1 infectivity reduction by washing hands with soap and water for 30 s (>3.0 +/- 0.4 log(10)) was significantly higher than treating hands with alcohol (2.8 +/- 1.5 log(10)). Washing with soap and water for 30 s removed genomic copies of MNV1 (>5 log(10)), noroviruses GI. 4 (>6 log(10)), and GII. 4 (4 log(10)) completely from all finger pads. Treating hands with propanol-based hand disinfectant showed little or no reduction to complete reduction with mean genomic copy reduction of noroviruses GI. 4, GII. 4, and MNV1 being >2.6, >3.3, and >1.2 log(10) polymerase chain reaction units respectively. Conclusions: Washing hands with soap and water is better than using alcohol-based hand disinfectants in removing noroviruses from hands. (C) 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.