Your Garden Hose: A Potential Health Risk Due to Legionella spp. Growth Facilitated by Free-Living Amoebae

详细信息    查看全文

• 作者：Jacqueline M. Thomas ; Torsten Thomas ; Richard M. Stuetz ; Nicholas J. Ashbolt
• 刊名：Environmental Science & Technology
• 出版年：2014
• 出版时间：September 2, 2014
• 年：2014
• 卷：48
• 期：17
• 页码：10456-10464
• 全文大小：338K
• ISSN：1520-5851

文摘

Common garden hoses may generate aerosols of inhalable size (鈮?0 渭m) during use. If humans inhale aerosols containing Legionella bacteria, Legionnaires鈥?disease or Pontiac fever may result. Clinical cases of these illnesses have been linked to garden hose use. The hose environment is ideal for the growth and interaction of Legionella and free-living amoebae (FLA) due to biofilm formation, elevated temperatures, and stagnation of water. However, the microbial densities and hose conditions necessary to quantify the human health risks have not been reported. Here we present data on FLA and Legionella spp. detected in water and biofilm from two types of garden hoses over 18 months. By culturing and qPCR, two genera of FLA were introduced via the drinking water supply and reached mean densities of 2.5 log₁₀ amoebae路mL^鈥? in garden hose water. Legionella spp. densities (likely including pathogenic L. pneumophila) were significantly higher in one type of hose (3.8 log₁₀ cells路mL^鈥?, p < 0.0001). A positive correlation existed between Vermamoebae vermiformis densities and Legionella spp. densities (r = 0.83, p < 0.028). The densities of Legionella spp. identified in the hoses were similar to those reported during legionellosis outbreaks in other situations. Therefore, we conclude that there is a health risk to susceptible users from the inhalation of garden hose aerosols.