There is no additional bactericidal efficacy of Environmental Protection Agency-registered disinfectant towelettes after surface drying or beyond label contact time.

BACKGROUND: Disinfectant towelettes are commonly used for surface disinfection to prevent health care-associated infections; however, there is limited consensus as to whether a surface needs to remain wet for the full label contact time after the disinfectant towelette has been used in order for complete efficacy to be achieved. The purpose of this study was to quantify the effect of contact time, including times before and after a product dries, on bactericidal efficacy of 6 towelette products registered by the Environmental Protection Agency .

METHODS: Six disinfectant towelette products were tested at varying contact times, including defined label contact times. Quantitative Environmental Protection Agency MB-33-00 was used to measure disinfectant efficacy against Staphylococcus aureus on Formica. Complete dry time for each disinfectant was measured gravimetrically.

RESULTS: There were significant differences in dry times among the towelette products; contact time did not have a significant effect on bactericidal efficacy. There was no longitudinal effect when a disinfectant's contact time was greater than defined label contact time, irrespective of whether the product was wet or dry on the surface.

DISCUSSION: Overall, bactericidal efficacy varied by towelette product tested and surface area wiped. Wiping larger surface areas may lead to decreased bactericidal efficacy but is product dependent.

CONCLUSIONS: There was no additional bactericidal effect after a product dried, indicating that extended contact times beyond when the product dries will not enhance disinfection.