Removal, Kill, and Transfer of Bacteria from Hands by Antibacterial or Nonantibacterial Soaps After Handling Raw Poultry.

Hand hygiene is broadly recognized as a critical intervention in reducing the spread of disease-causing pathogens in both professional and personal uses. In this study, the impact of antibacterial (AB) or nonantibacterial soaps on the removal and postwash transfer of E. coli following the handling of raw poultry was assessed. Baseline bacterial contamination ranged between 107 and 109 CFU per hand. Hands were washed for 30 s in 40°C ± 2°C tap water using 2 mL of AB soap (0.5% and 1.0% Chloroxylenol, 0.5% Benzalkonium Chloride, or 4.0% Chlorhexidine Gluconate), non-AB soap (cosmetic/plain soap), or water. Postwash, water, and non-AB soap had a mean 3.63 and 3.65 Log10 reduction of E. coli on hands. AB treatments had a mean 4.19-4.35 Log10 reduction. Rinse water had mean bacterial counts of 8.62 and 8.88 Log10 CFU/mL for non-AB soap and water and 5.37-6.90 Log10 CFU/mL for AB treatments. Bacterial transfer was assessed by following the test subject's handling of a sterile polymer knife handle for 30 s postwash. E. coli transfer ranged from 263 to 903 CFU/handle for AB soaps and 1572 or 1709 CFU/handle for water and non-AB soap. Differences between AB and non-AB treatments were statistically significant (p < 0.0001) for hands and rinse water. Differences in transfer from hands to knife handle were not statistically significant (p = 0.139). Combined, these data highlight significant differences in the performance of AB soaps relative to non-AB soaps in a food handling environment-specific usage example and provide an unexplored assessment of the bactericidal vs. removal effects of AB vs. non-AB soaps on bacteria removed from the hands. These data reinforce the importance of hand hygiene, provide new details on the differences between AB vs. non-AB soaps, and highlight potential differences to inform food handling environment operators and public health personnel on how these products may impact food safety.

Inactivation kinetics of benzalkonium chloride and ethanol-based hand sanitizers against a betacoronavirus and an alphacoronavirus.

Background: Hand hygiene is critical to lower the potential for the spread of SARS-CoV-2 and other infectious agents by direct contact. When running water and soap are not available for hand hygiene, ethanol-based hand sanitizers are currently the recommended standard of care [1-3]. Though recently published data showed comparable in vitro effectiveness of benzalkonium chloride (BAK)-based and ethanol-based hand sanitizers against SARS-CoV-2 virus, a paucity of peer-reviewed data on the effectiveness of these formulations against other types of infective coronaviruses remains. This work assessed human coronavirus HCoV-229E (genus Alphacoronavirus) concurrently with SARS-CoV-2, Isolate USA-WA1/2020 (genus Betacoronavirus) to fill this gap. Methods: The test was conducted according to EN14476:2013-A2:2019 [EN14476] Quantitative Suspension Test for the Evaluation of Virucidal Activity in the Medical Area [4]. Two BAK-based hand sanitizers, five ethanol-based hand sanitizers, and an 80% ethanol reference formulation were tested for antiviral activity against SARS-CoV-2 and HCoV-229E at 15- and 30- second contact times. Results: Both SARS-CoV-2 and HCoV-229E were reduced by greater than 4.00-log10 within 15 seconds of contact. Virus decay constants (k) following first-order kinetics were similar for BAK and ethanol-based formulations against both test viruses. The SARS-CoV-2 results reported herein mirrored previous data reported by Herdt et al. (2021). Conclusion: BAK and ethanol hand sanitizer formulations inactivate SARS-CoV-2 and HCoV-229E at similar rates. This data supports previously published effectiveness data for both chemistries and indicates that additional coronavirus strains and variants would demonstrate similar inactivation trends.

Inactivation of SARS-CoV-2 by 2 commercially available Benzalkonium chloride-based hand sanitizers in comparison with an 80% ethanol-based hand sanitizer.

BACKGROUND: The CDC and WHO recommend alcohol-based hand sanitizers to inactivate severe acute respiratory syndrome coronavirus-2 [SARS-CoV-2]. AIM: Benzalkonium chloride [BAK] is another hand sanitizer active ingredient that could be used in response to the global pandemic. Deployment of BAK-based hand sanitizers could reduce shortages of alcohol products and increase hand hygiene options where there are social, physical, and toxicological constraints on alcohol use. METHODS: Two commercially available BAK-based hand sanitizers, a concentrate diluted on-site with water and a ready-to-use product, were tested for activity against SARS-CoV-2 in the European Norm Virucidal Activity Suspension Test [EN14476]. A WHO and CDC-recommended 80% alcohol-based hand sanitizer formulation was tested in parallel. FINDINGS: Both BAK formulations demonstrated a ≥4.0 log10 reduction of SARS-CoV-2 in 30 seconds, meeting the EN14476 performance standard for virucidal activity against SARS-CoV-2 and matching the in vitro effectiveness of the ethanol-based sanitizer. CONCLUSION: These findings indicate that a commercial BAK hand hygiene formulation may be another effective means of inactivating the SARS-CoV-2 virus and could be considered as option for pandemic response.