Bentham R H, Broadbent C R
Repatriation General Hospital, Daw Park, South Australia.
Epidemiol Infect. 1993 Oct;111(2):287-95. doi: 10.1017/s0950268800056995.
Cooling towers have been demonstrated to be amplifiers and disseminators of legionella, the causative organism of Legionnaires' disease. Community outbreaks associated with cooling towers have been reported with several common factors. Small towers (< 300 kW) have predominantly been implicated in outbreaks. Cooling tower-associated outbreaks are most frequent in autumn, and frequently implicated systems have been operated after a period of shutdown. This paper reports field study data relating system operation to legionella colonization of systems. Operating systems have been shown to be more frequently colonized by legionella than shutdown systems. In some cases operation of systems after periods of shutdown raised legionella concentrations from below detection limits to between 50 and 950 c.f.u./ml within 10 min. These data and previously reported data relating to biofilm and sediment colonization of the systems, and community outbreaks of Legionnaires' disease, have been used to develop a model explaining the seasonal nature of outbreaks associated with irregularly operated, small cooling tower systems.
冷却塔已被证明是军团菌的放大器和传播者，军团菌是军团病的致病微生物。已报告了与冷却塔相关的社区疫情，并存在几个共同因素。小型冷却塔（<300千瓦）主要与疫情有关。与冷却塔相关的疫情在秋季最为频繁，且经常涉及在停机一段时间后运行的系统。本文报告了将系统运行与系统中军团菌定殖相关的现场研究数据。已表明运行中的系统比停机系统更频繁地被军团菌定殖。在某些情况下，停机一段时间后系统运行会使军团菌浓度在10分钟内从检测限以下升至50至950菌落形成单位/毫升之间。这些数据以及先前报告的与系统生物膜和沉积物定殖以及军团病社区疫情相关的数据，已被用于建立一个模型，以解释与运行不规律的小型冷却塔系统相关的疫情的季节性特征。
