Virucidal activities of novel hand hygiene and surface disinfectant formulations containing EGCG-palmitates (EC16).

BACKGROUND: Non-toxic hand hygiene and surface disinfectant products with virucidal activity against alcohol-resistant nonenveloped norovirus are in urgent need. METHOD: Alcohol-based formulations were made with epigallocatechin-3-gallate-palmitate (EC16), an FDA accepted food additive. Based on in-house testing of formulations, 3 prototypes, PTV80 hand gel, PST70 surface disinfectant spray and PST70 surface disinfectant wipe, were selected from in-house tests for independent testing at GLP (good laboratory practice) laboratories according to EN 14476:2019 (hand gel), ASTM test method E1053-20 (spray), and ASTM E2362-15, E1053, and ASTM E2896-12 (wipe). RESULTS: The PTV80 hand gel prototype demonstrated a >99.999% reduction of murine norovirus S99 infectivity in 60 seconds. Carrier testing of the PST70 surface spray and surface wipe demonstrated reduction of feline calicivirus infectivity by >99.99% in 60 seconds. In addition, testing with human coronavirus and human herpes simplex virus demonstrated >99.99% efficacy in 60 seconds, consistent with broad spectrum virucidal activity. CONCLUSIONS: The novel non-toxic prototypes containing EC16 were found to be suitable for use in future hand sanitizer gel, surface disinfectant spray and wipe products against norovirus. Products based on these formulations could be used safely to help prevent and control norovirus and other emerging virus outbreaks, pending future studies.

A topical cream containing a zinc gel (allergy guard) as a prophylactic against latex glove-related contact dermatitis.

BACKGROUND: Many health care workers are sensitized to the proteins in natural rubber latex and get contact dermatitis as a result of wearing latex gloves. OBJECTIVE: The aim of the study was to evaluate a topical formulation containing a zinc gel (Allergy Guard) as a prophylactic against latex glove-related contact dermatitis. METHODS: The study was carried out with volunteers who exhibited mild to moderate contact dermatitis (type IV) after wearing latex gloves as per the protocol. RESULTS: Allergy Guard significantly reduced skin irritation in volunteers who exhibited type IV hypersensitivity when exposed to latex gloves. Allergy Guard also exhibited a barrier effect as shown by the permeation of chlorophyllin dye into the skin of volunteers. Allergy Guard prevented dermal irritation induced by sodium lauryl sulfate. CONCLUSION: Topical formulations containing a zinc gel may be used to delay or prevent latex sensitivity, especially among health care professionals.

Evaluation of the antimicrobial efficacy of urinary catheters impregnated with antiseptics in an in vitro urinary tract model.

OBJECTIVES: To evaluate the long-term efficacy of urinary Foley catheters (latex and silicone) impregnated with (1) chlorhexidine and silver sulfadiazine (CXS) and (2) chlorhexidine, silver sulfadiazine, and triclosan (CXST) in inhibiting extra-luminal bacterial adherence and to compare their efficacy with that of silver hydrogel latex (SH) and nitrofurazone-treated silicone (NF) catheters. DESIGN: The antimicrobial spectrum of these catheters was evaluated using a zone of inhibition assay. A novel in vitro urinary tract model was developed to study the potential in vivo efficacy of antimicrobial catheters in preventing extraluminal bacterial colonization. The "meatus" was inoculated daily with Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Enterococcus faecalis, Pseudomonas aerginosa, and Candida albicans. The "bladder" portion of the model was cultured daily to determine bacterial growth. RESULTS: Both CXS and CXST catheters had a broader antimicrobial spectrum than SH and NF catheters. In the in vitro model, CXST latex and silicone catheters exhibited significantly better efficacy (3 to 25days) against uropathogens, compared with CXS (1 to 14 days) and control (0 to 5 days) catheters (P = .01). CXST latex catheters exhibited significantly longer protection against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa, compared with SH catheters (P = .01). CXST silicone catheters resisted colonization with Staphylococcus aureus and Staphylococcus epidermidis for a significantly longer period (23 to 24 days) than did NF catheters (9 to 11 days) (P = .01). CONCLUSION: Catheters impregnated with synergistic combinations of chlorhexidine, silver sulfadiazine, and triclosan exhibited broad-spectrum, long-term resistance against microbial colonization on their outer surfaces.

Evaluation of an antimicrobial-impregnated continuous ambulatory peritoneal dialysis catheter for infection control in rats.

Infection is the most serious complication arising in long-term continuous ambulatory peritoneal dialysis (CAPD), specifically peritonitis and exit-site infection. The initial weeks after implantation is the crucial period during which bacterial colonization of the catheter results in maximal morbidity, with Staphylococcus aureus being the most virulent organism. We developed an antimicrobial-impregnated CAPD catheter by impregnating the cuff and tubing with chlorhexidine, silver sulfadiazine, and triclosan in a polymer matrix. The antimicrobial spectrum and duration were shown by measuring zones of inhibition to various bacteria and fungi over the course of 5 to 10 days. Activity also was assessed subsequent to soaking in trypticase soy broth containing 20% bovine serum over the course of 1, 3, and 7 days. Significant antimicrobial activity was shown against all organisms tested for, with particular efficacy against gram-positive bacteria. Catheters were implanted in rats followed by inoculation of the exit site with S aureus. Seven days postimplantation, 0% of the impregnated catheters were colonized intraperitoneally compared with 100% of the control catheters. Similarly, 12.5% of the impregnated catheters were colonized at the exit site, whereas 100% of the controls were colonized. Histologic analysis showed that this combination and concentration of antimicrobials did not retard healing or cause increased inflammation compared with control catheters after 3, 10, and 24 days postimplantation in noninoculated rats.