上海口岸管道水中军团菌污染状况及其细胞内生长能力研究

目的 了解口岸公共场所管道水军团菌污染状况和细菌在细胞内的生长能力。方法 采集上海市口岸管道水132份,采用GVPC(军团菌选择性培养基)培养计数法对水样中军团菌进行定性和定量分析。用小鼠巨噬细胞J774细胞对分离菌株进行菌株致病性研究。结果 平板培养法检测管道水中军团菌阳性率为18.94%, 25份培养阳性标本中军团菌定量数值为50～1 320菌落形成单位(CFU)/L。分离的25株军团菌中17株是嗜肺军团菌;其中血清1型2株、8型13株、7型1株、5型1株;其余8株为米克戴德军团菌。细胞内生长实验结果显示, 4个血清型的嗜肺军团菌均具有很高的细胞内生长能力,而米克戴德军团菌细胞内生长能力较低。结论 管道水中军团菌污染率和含菌量较高,且菌株具有很高的细胞内生长能力,提示其具有一定致病性,有引起军团菌病的危险,应采取相应消毒和预防措施。

Contamination and intracellular growth ability of Legionella in pipe water system in Shanghai Port,China

To investigate Legionella pollution prevalence and intracellular growth ability in pipe water from two airports in Shanghai, a total of 132 pipe water samples were collected from Shanghai port in 2010. The culture method was used to do qualitative and quantitative analysis of Legionella in pipe water samples. The serotypes of strains were determined by agglutinating. The intracellular growth ability of the Legionella isolates was tested by cell culture methods with mouse macrophage J774. Of the 132 water samples, 18.94% were observed to be positive with Legionella. The amount of Legionella in each positive sample was 50 to 1 320 CFU/200mL. Among the 25 isolates, 17 were Legionella pneumophila including 2 Lp1, one Lp5, one Lp7, and 13 Lp8, and 8 were Legionella micdadei. We selected five strains of different species and serotypes to infect J774, and the results showed that all the L. pneumophila strains have high intracellular growth ability, while L. micdadei has lower intracellular growth ability. It's suggested that there is high pollution prevalence of Legionella in pipe waters in Shanghai Port, which illuminated an urgent need for dealing with the potential risk of Legionella in pipe waters, through improved control and prevention strategies.