Effects of Different Hand Washing Processes on the Efficiency of Bacterial Load Reduction and Economics Estimation

Abstract

Introduction and purpose: Hand hygiene is an international priority for the elimination of nosocomial infections. This research aimed to investigate the effects of handwashing conditions on bacterial removal efficiency and its economic estimation in a military hospital in Tehran. Methods: In total, 20 hospital staff were selected from volunteers. The water temperature (WTe) (20 ºC, 30 ºC, and 40 ºC), soap volume (SV) (0.5, 1.25, and 2 ml), and washing time (WTi) (10, 20, 35, and 50 sec,) were investigated. The standard strain of Escherichia coli with identified ATCC (25922) was prepared from a reference laboratory and fresh culture was prepared on nutrient broth medium. Primarily, the hands of participants were thoroughly washed with soap and water, then contaminated with 1 ml of bacterial suspension with 1.5×104 colony-forming unit/ml density. After 3 min of handwashing, sampling was performed based on research protocols. The samples were transferred on eosin methylene blue agar and incubated at 37 ºC for 48 h. After this time, the growth bacteria were considered the residual contamination on the hands. Results: Based on findings, various studied conditions had no effect on bacterial removal efficiency. Accordingly, WTi=20 sec, SV=0.5 ml, and ordinary WTe (20 ºC) can be used for handwashing with appropriate perfornance. For 500 people, annually 627 million Rials for water and water heating, 135 million Rials for soap, and 316 days a year on handwashing can be saved. Conclusion: Optimization of the handwashing process while ensuring hand hygiene saves costs.

Keywords

• bacterial load
• economic estimation
• hand hygiene
• hand washing
• nosocomial infections