Demonstrating the persistent antibacterial efficacy of a hand sanitizer containing benzalkonium chloride on human skin at 1, 2, and 4 hours after application

Abstract

Background: Use of hand sanitizers has become a cornerstone in clinical practice for the prevention of disease transmission between practitioners and patients. Traditionally, these preparations have relied on ethanol (60%-70%) for bactericidal action. Methods: This study was conducted to measure the persistence of antibacterial activity of 2 preparations. One was a non-alcohol-based formulation using benzalkonium chloride (BK) (0.12%) and the other was an ethanol-based formulation (63%) (comparator product). The persistence of antibacterial activity was measured against Staphylococcus aureus using a technique modification prescribed in American Society for Testing and Materials protocol E2752-10 at up to 4 hours after application. Results: The test product (BK) produced a marked reduction in colony-forming units at each of the 3 time points tested (3.75-4.16-log 10 reductions), whereas the comparator produced less than 1-log 10 reduction over the same time. The differences were highly significant. Discussion: In the course of patient care or examination, there are instances where opportunities exist for the practitioner's hands to become contaminated (eg, key boards and tables). Persistent antibacterial activity would reduce the chances of transfer to the patient. Conclusions: These results show a major improvement in persistent antibacterial activity for the BK formulation compared to the comparator ethanol-based formulation.

Managing Vibrio cholerae with a local beverage: preparation of an affordable ethanol based hand sanitizer

“…Coupled with the emergence of alcohol tolerant microorganisms and bacterial adaptation in multi drug resistant strains such as E. faecium, infection control is becoming more complicated in clinical settings, where persistent antimicrobial activity is vital. Therefore alternative antibacterials such as Benzalkonium Chloride could be considered more useful under such settings by providing a longer residual antibacterial effect to minimise transmission of pathogens among patients and healthcare workers [29,31].…”

Evaluation of a benzalkonium chloride hand sanitizer in reducing transient Staphylococcus aureus bacterial skin contamination in health care workers

“…This count is consistent with the number of S aureus colony forming units found on the hands of HCWs in a previous study by Pittet et al, 17 therefore, we believed that our test subject population was representative. Because the BZK test product has a known persistence on human skin for up to 4 hours, 1 we theorized that there would be a decrease in the colony count on the afternoon plate from the morning plate as HCWs used BZK throughout the day. We also theorized that there would be a smaller decrease in the colony count in the ethanol week afternoon plate because of the known lack of persistent antimicrobial activity of ethanol.…”

“…That study showed significant killing of S aureus on the skin up to 4 hours postapplication for the BZK sanitizer, compared with essentially no persistent antibacterial activity of the ethanol sanitizer. 1 In the March 8, 2019, Morbidity and Mortality Weekly Report, the Centers for Disease Control and Prevention (CDC) expressed concern about a failure of S aureus nosocomial infections to continue the downward rate trend that had been seen for several years. This statement was taken from that Morbidity and Mortality Weekly Report, "S aureus infections account for substantial morbidity in the United States.…”

Mitochondrial Dysfunctions May Be One of the Major Causative Factors Underlying Detrimental Effects of Benzalkonium Chloride

“…BAC, a membrane-active cationic surfactant, is remarkable by its stability, high water solubility, low cost, and superior biocidal activity against most bacteria, fungi, algae, and some viruses [3][4][5][6]. It is extensively employed as an antimicrobial in hospitals, agriculture, and the food industry [4], in ophthalmic preparations [7], nasal sprays [8], multidose albuterol nebulizer solutions [9,10], as a skin disinfectant and hand sanitizer [11], in cosmetics, numerous toothpastes and mouth rinses, lozenges, and dental restoratives [12][13][14][15][16].…”