Study of Gorge Fisher Plumbing System Effects on Growth Inhibition and Amplification of Legionella pneumophila by Culture and PCR Based on 16sRNA and mip Genes

Abstract

Background: Legionella is an aquatic bacterium that causes Legionnaires' fever. Objectives: This study aimed to investigate the effect of Legionella stopper pipes and fittings of George Fisher Company on controlling Legionella growth in indoor water supply systems. Methods: Fifty-six samples of hot and cold-water systems were collected and characterized. The culture was performed in BCYE agar. Molecular detection was performed by PCR. Results: The mean residual chlorine was 0.73 to 0.88 mg/L. Culture results were positive in 58.8% of George Fischer samples and 23.5% of Ray Ho samples. Sixty percent of Taleghani hospital samples were positive. The PCR results based on 16sRNA in the George Fischer system, Ray Ho piping, and Taleghani hospital were positive in 35.2%, 45.4%, and 54.5%, respectively. Based on the mip gene, 82.3% of George Fischer samples, 54.5% of RayHo samples, and 20% of Taleghani hospital samples were positive. Conclusions: GeorFischer's Legionella stopper pipes and fittings demonstrated appropriate antibacterial properties against Legionella pneumophila. Due to the growth inhibition of Legionella in the indoor water supply system, it can be a suitable option for plumbing systems.