Textiles treated with antimicrobial agents are emerging as new strategies to reduce acquisition of healthcare-associated infections (HAIs). Essential to development/validation of these textiles are standard methods for the testing antimicrobial textile efficacy. Our laboratory has developed new testing methods, the fabric challenge assays, to recapitulate each transmission method and test the efficacy of antimicrobial textiles in a more “real world” simulation. 5 × 105 colony-forming units/ml (CFU/ml) MRSA suspensions were grown. 15 × 15 cm2 swatches of control, antimicrobial, hydrophobic barrier, and VTT003 fabric were inoculated with MRSA either by aerosol, splatter, or direct contact. Inoculated fabric was left at room temperature for 0, 30, or 60 min. Fabric was then transferred to buffer and shaken for 3 min at 400 rpm. A liquid suspension (0.1 ml) was then plated onto blood agar, grown overnight at 37°C, and colonies were counted. In the aerosol test, at 0 min, VTT003 significantly reduced MRSA by 78.52 ± 10.26 % compared to control fabric. At 30 min, antimicrobial reduced MRSA levels by 91.48 ± 8.52 %. In the splatter test, at 0 min, antimicrobial, hydrophobic barrier, and VTT003 fabrics reduced MRSA levels by 98.56 ± 1.44, 83.91 ± 13.16, and 100.00 ± 0.03 %, respectively. At 30 min, hydrophobic barrier and VTT003 reduced levels by 82.63 ± 17.37 and 100.00 ± 0.00 %, respectively. At 60 min, hydrophobic barrier and VTT003 abrogated MRSA levels. In the contact test, at 0 min, hydrophobic barrier and VTT003 reduced MRSA levels by 99.06 ± 0.94 and 97.08 ± 2.92 %, respectively. At 30 min, hydrophobic barrier and VTT003 reduced MRSA levels by 100.00 ± 0.03 and 19.38 ± 19.38 %, respectively. At 60 min, hydrophobic barrier and VTT003 abrogated MRSA levels. The fabric challenge assays are a novel method for evaluation of antimicrobial textile performance and should be considered in the development of standards and testing methods for all antimicrobial textiles intended for use in healthcare infection control strategies.

BackgroundMultiple mobile ultraviolet (UV) light devices are available for disinfection of hospital rooms, but few data are available on the relative ability of devices to reduce surface contamination and ease of use. The objective of the present study was to compare the antimicrobial efficacy of several devices in a laboratory setting.MethodsUsing a modification of the ASTM International method E2197, spores of Clostridioides difficile(ATCC strain BAA-1870) suspended in phosphate-buffered saline (PBS) with 5% fetal calf serum were inoculated onto 20 mm stainless steel disks and dried. Disks were attached to right and left bedrails, under bed, call button, chair armrest, floor near device, table top, table bottom, floor far from device, toilet seat and grab bar and sink handle in a mock 6.4 × 4.1-meter hospital room with a 1.5 × 2.4-meter bathroom. Disks were exposed using cycle times and device placements recommended by device manufacturers. Spores from exposed disks and unexposed control disks were recovered in PBS with Triton X-100, enumerated using dilution plating, and log10reductions were determined by comparing the number of spores recovered from exposed and control disks. Times for set-up, treatment and resetting the space were recorded for each device. Results were expressed as mean log10reductions and percent reduction/minute of room vacancy. Results were compared using Kruskall-Wallis nonparametric analysis.ResultsMean log10reductions, percent reductions, run times for patient rooms and bathroom, setup/reset times, total room vacancy times, and percent reduction/minute of room vacancy are shown in the Table. There were no significant differences in percent reductions between different locations for each device. There were, however, statistically significant differences between microbial reductions between the different machines (P < 0.05 for all comparisons).ConclusionThere are many factors to consider in selecting a UV device. These considerations should include mean log10reduction, total vacancy times and percent reduction achieved/minute of room vacancy. Disclosures All authors: No reported disclosures.