Antimicrobial disinfection effect of a laundering procedure for hospital textiles against various indicator bacteria and fungi using different substrates for simulating human excrements

Recent studies confirm the increase of nosocomial infections and microbial resistance. One of the possible causes is infected textiles due to inappropriate laundering procedures. Most Slovenian laundries use thermal laundering procedures with high energy and water consumption to disinfect hospital textiles. In addition to this fact, there is an increasing number of hospital textiles composed of cotton/polyester blends that cannot endure high temperatures of thermal disinfection. On the other hand, decreasing the temperature of laundering procedures enhances the possibility of pathogenic microorganisms to survive the laundering procedure. In our research, we determined the antimicrobic laundering effect by simulating a common laundering procedure for hospital textiles in the laboratory washing machine at different temperatures by the use of bioindicators. Enterococcus faecium, Staphylococcus aureus, Mycobacterium terrae, Enterobacter aerogenes, and Pseudomonas aeruginosa were used for determining the antibacterial laundering effect. Candida albicans was used for determining the antifungal laundering effect. Swine blood, artificial sweat, and swine fat were used as substrates for simulating human excrements and were inoculated together with the chosen microorganisms onto cotton pieces to simulate real laundering conditions. It was found that E. faecium, S. aureus, E. aerogenes, and P. aeruginosa survived at 60 °C, but no microorganisms were found at 75 °C.