Lasting hand self-disinfection: A backup for hospital hand hygiene?

SHEA/IDSA/APIC Practice Recommendation: Strategies to prevent healthcare-associated infections through hand hygiene: 2022 Update

The purpose of this document is to highlight practical recommendations to assist acute-care hospitals in prioritization and implementation of strategies to prevent healthcare-associated infections through hand hygiene. This document updates the Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals through Hand Hygiene, published in 2014. This expert guidance document is sponsored by the Society for Healthcare Epidemiology (SHEA). It is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America, the Association for Professionals in Infection Control and Epidemiology, the American Hospital Association, and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise.

Evaluation of the Residual Disinfection Effects of Commonly Used Skin Disinfectants against Viruses: An Innovative Contact Transmission Control Method

Lasting disinfection effects, that is, the residual disinfection effects (RDEs), of skin-coated disinfectants have rarely been considered for infection control owing to the challenges involved in the accurate evaluation of RDEs. In this study, we constructed a new skin evaluation model and determined the RDEs of existing disinfectants against viruses. Our results showed that ethanol and isopropanol had no RDE, whereas povidone-iodine, chlorhexidine gluconate, and benzalkonium chloride (BAC) exhibited RDEs, with 10% povidone-iodine and 0.2% BAC showing particularly strong RDEs. The RDE of 0.2% BAC was strong enough to reduce the median survival times of severe acute respiratory syndrome coronavirus-2, human coronavirus-OC43, and influenza virus from 670 to 5.2, 1300 to 12, and 120 to 4.2 min, respectively. Additionally, this strong RDE was maintained even 4 h after coating the skin. Clinical data also showed that the strong RDE of 0.2% BAC was maintained for more than 2 h. Thus, applying disinfectants with strong RDEs on the skin correlates with a reduction in virus survival time and appears to create a skin surface environment that is not conducive to virus survival. A prolonged reduction in virus survival decreases the contact transmission risk, thereby enabling stronger infection control.

Surgical hand preparation with chlorhexidine soap or povidone iodine: new methods to increase immediate and residual effectiveness, and provide a safe alternative to alcohol solutions

BACKGROUND

Surgical use of 4% chlorhexidine soap (CHX-4) and 10% povidone iodine (PVP-I-10) does not meet the standards defined by EN 12791.

AIM

To investigate the possibility of increasing the immediate and residual effects of these antiseptics.

METHODS

Over three consecutive weeks, n-propanol, standard CHX-4 and PVP-I-10 were tested in two experimental groups of volunteers. The new method for applying the antiseptic substances involved standard hand rub and rinse of CHX-4 or PVP-I-10, followed by application of an aqueous solution based on 5% chlorhexidine or PVP-I-10 with no further rinsing of the hands prior to donning gloves. Samples were taken to assess immediate and residual effects, analysing the logarithmic reduction of colony-forming units.

FINDINGS

At t=0 h, n-propanol was superior in bactericidal effect to standard CHX-4 (P<0.05), but the new chlorhexidine protocol was superior to both standard CHX-4 (P<0.01) and n-propanol (P<0.05); the same effect was observed at t=3 h (residual effect). At t=0 h, n-propanol was significantly superior to standard PVP-I-10, but the new PVP-I-10 protocol was superior, although not significantly, to n-propanol. There was no significant residual effect at t=3 h.

CONCLUSION

The new protocol for chlorhexidine application permits surgical hand preparation with chlorhexidine, as a safe alternative to alcohol solutions, because it meets the standards defined by EN 12791.

Evaluation of antimicrobial persistent activity of alcohol-based hand antiseptics against bacterial contamination

The purpose of this study was to evaluate persistent activity of three alcohol-based antiseptics widely used in the clinical routine containing chlorhexidine, triclosan or mecetronium after hand disinfection. Four tests were used to evaluate the antimicrobial activity of antiseptics on: (i) resident microbiota; (ii) nutrient agar plates (NAP) subsequently inoculated with a test organism; and transient microbiota acquired by contact with dry hands (iii), or (iv) a wet inert surface that had been artificially contaminated. Four reference strains (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis) and an Acinetobacter baumannii strain responsible for a hospital outbreak were used as transient microbiota. Antimicrobial activity was calculated according to the CFUs reduction by reference to non-disinfected control hands. The antiseptics were applied according to European Standard EN1500. Solutions containing chlorhexidine or triclosan showed some persistent effects on transient microbiota on inert humid surfaces and NAP, but not on contaminated dry hands. Solutions containing mecetronium showed no persistent effect on transient flora in any of the trials. All alcohol-based antiseptics tested were more effective against resident flora than soap. No persistent activity was observed for A. baumannii in any of the trials. Chlorhexidine and triclosan are preferred when an antiseptic with persistent activity is desired, but a moist environment appears to be necessary for that antibacterial activity. Accordingly, relevant conclusions regarding the persistent activity of antiseptics for clinical practice and protection against bacterial contamination cannot be derived from this study for the alcoholic solutions tested.