Abstract：
BACKGROUND: Legionella disease can manifest as severe respiratory tract infection with a high mortality rate and is sometimes associated with a hospital outbreak by a contaminated water supply. A patient with breast cancer admitted about a month before. High fever was observed 18 days after admission and the Legionella antigen test showed the positive result.
METHODS: Due to the incidence of Legionella infection, we demonstrated the active surveillance of Legionella contamination in the entire hospital.
RESULTS: Cultures of her environmental samples revealed that hot water in two bathrooms were contaminated with Legionella. In our hospital, the hot water is heated and pumped up on the roof and distributed to each room. The contaminated bathrooms were related to the same plumbing. Therefore, we further collected samples throughout the hot water system. Legionella was not detected in the central part of the system. However, we detected Legionella in the hot water sampled from other five rooms, which were also associated with the same plumbing of the two bathrooms. The temperature and chlorine concentration of the hot water were not high enough to inactivate Legionella at the end of the plumbing. After the adjustment of the water temperature and chlorine concentration, Legionella became undetectable. Our prompt and active surveillance successfully identified the plumbing of the hot water system as the source of Legionella contamination and took precautions against future outbreaks.
CONCLUSIONS: Monitoring of water temperature and chloride concentration at the end of the hot water circulation is important to prevent nosocomial Legionella disease.
METHODS: Due to the incidence of Legionella infection, we demonstrated the active surveillance of Legionella contamination in the entire hospital.
RESULTS: Cultures of her environmental samples revealed that hot water in two bathrooms were contaminated with Legionella. In our hospital, the hot water is heated and pumped up on the roof and distributed to each room. The contaminated bathrooms were related to the same plumbing. Therefore, we further collected samples throughout the hot water system. Legionella was not detected in the central part of the system. However, we detected Legionella in the hot water sampled from other five rooms, which were also associated with the same plumbing of the two bathrooms. The temperature and chlorine concentration of the hot water were not high enough to inactivate Legionella at the end of the plumbing. After the adjustment of the water temperature and chlorine concentration, Legionella became undetectable. Our prompt and active surveillance successfully identified the plumbing of the hot water system as the source of Legionella contamination and took precautions against future outbreaks.
CONCLUSIONS: Monitoring of water temperature and chloride concentration at the end of the hot water circulation is important to prevent nosocomial Legionella disease.
摘要：
背景：军团菌病可表现为严重的呼吸道感染，死亡率高，有时与受污染的供水引起的医院暴发有关。一名乳腺癌患者大约一个月前入院。入院18天后出现高热，军团菌抗原检测显示阳性结果。
方法：由于军团菌感染的发生率，我们证明了整个医院对军团菌污染的积极监测。
结果：她的环境样本的培养显示，两个浴室的热水被军团菌污染。在我们的医院里,热水被加热和抽到屋顶上，分配到每个房间。受污染的浴室与同一管道有关。因此,我们进一步收集了整个热水系统的样本。在系统的中心部分未检测到军团菌。然而,我们在其他五个房间的热水中检测到军团菌，这也与两个浴室的相同管道有关。热水的温度和氯浓度不足以使管道末端的军团菌失活。调整水温和氯浓度后，军团菌变得无法检测到。我们迅速而积极的监测成功地确定了热水系统的管道是军团菌污染的来源，并对未来的疫情采取了预防措施。
结论：监测热水循环结束时的水温和氯化物浓度对预防医院军团菌病很重要。
方法：由于军团菌感染的发生率，我们证明了整个医院对军团菌污染的积极监测。
结果：她的环境样本的培养显示，两个浴室的热水被军团菌污染。在我们的医院里,热水被加热和抽到屋顶上，分配到每个房间。受污染的浴室与同一管道有关。因此,我们进一步收集了整个热水系统的样本。在系统的中心部分未检测到军团菌。然而,我们在其他五个房间的热水中检测到军团菌，这也与两个浴室的相同管道有关。热水的温度和氯浓度不足以使管道末端的军团菌失活。调整水温和氯浓度后，军团菌变得无法检测到。我们迅速而积极的监测成功地确定了热水系统的管道是军团菌污染的来源，并对未来的疫情采取了预防措施。
结论：监测热水循环结束时的水温和氯化物浓度对预防医院军团菌病很重要。
