Premise plumbing promotes the regrowth and survival of opportunistic pathogens, such as Legionella pneumophila (L. pneumophila), especially within biofilms. The purpose of this study was to investigate the effectiveness of chlorine disinfection against L. pneumophila serogroup 1 and serogroup 2–15 planktonic form and biofilms. Planktonic cells were able to survive during the study period in the presence of chlorine at recommended free chlorine levels (0.2–0.5 mg/L). Biofilms were developed on galvanized steel and polyvinyl chloride (PVC) for 18 and 30 days and exposed to 50, 100, 150, and 200 mg/L for 2 hours. No colony appeared immediately after chlorination; however, persistent cells were able to tolerate treatment and continue to grow on subsequent days. The biofilm formation was evaluated by atomic force microscopy. This study demonstrates that the biofilm formed on the surfaces of plumbing materials increases bacterial resistance against high levels of chlorination. A new approach towards monitoring and eradicating L. pneumophila from water systems is required.

前提管道可以促进机会病原体（例如军团菌肺炎军团菌（L. pneumophila））的再生和存活，尤其是在生物膜内。这项研究的目的是调查氯消毒对肺炎链球菌的有效性血清群1和2-15的浮游形式和生物膜。在建议的游离氯水平（0.2–0.5 mg / L）下，在存在氯的情况下，浮游生物细胞能够存活。生物膜在镀锌钢和聚氯乙烯（PVC）上显影18天和30天，然后分别暴露于50、100、150和200 mg / L 2小时。氯化后没有菌落出现。然而，持久性细胞能够耐受治疗并在随后的几天继续生长。通过原子力显微镜评价生物膜的形成。这项研究表明，在管道材料表面形成的生物膜可提高细菌抵抗高水平氯化作用的能力。需要一种从水系统中监测和根除嗜肺乳杆菌的新方法。