广西军团菌流行病学监测研究

Study on epidemiological surveillance of Legionella in Guangxi

目的了解广西军团菌在肺炎病人感染和外环境污染状况,为制定有效的防控措施提供科学依据。方法 2009～2012年在广西部分地区调查和采集符合病例定义的肺炎病例尿液、下呼吸道标本以及公共场所水体进行嗜肺军团菌尿抗原检测、病原培养及鉴定。结果对1 052例肺炎病例调查和采样未检出军团菌阳性;416份公共场所水体标本共检出嗜肺军团菌97株,阳性率23.32%,以7～9月检出阳性率为最高(36.36%～42.42%),中央空调冷却塔水阳性率高达31.56%;不同类型公共场所以酒店、宾馆阳性率最高为44.23%,次为医疗机构40.00%;97株嗜肺军团菌中Lp1型占55.67%,Lp2-15型占44.33%。40株Lp1型经脉冲场凝胶电泳(PFGE)分型,获得36种基因型别,带型分散,未发现绝对优势带型。结论尽管未发现军团菌所致肺炎病例,但公共场所水体军团菌污染严重,对人群健康构成潜在威胁,需加强人群和公共场所集中空调通风系统军团菌监测和卫生监督。

Objective To determine the prevalence of legionella bacteria in patients with pneumonia and the environments in Guangxi, which will he helpfid for developing effective control measures. Methods Samples of urine and lower respiratory traet of patients with pneumonia meeting the case definitions as well as water samples in public were collected during 2009 and 2012. Urine antigen testing, bacterial culture and identification were carried out on the samples collected. Results No legionella bacteria was detected from 1 052 cas^-＇s with pneumonia. A total of 97 strains of Legionella pneumophila were isolated fi＇om 416 water samples in public, yielding a positive rate of 23.32%. The highest positive rate of 36.36% - 42.42% was found between July and September. A high positive rate of 31.56% was observed in cooling tower water of central air conditioning systems. For different public places, the highest positive rate of 44.23% was tbund in hotels, followed by hospitals （40.00%）. Of the 97 strains of Legionella pneumophila isolated, 55.67% was LP1 and 44.33% was LP2-15. A total of 36 genotypes was found in those 40 strains of LP1 using the assay of pulsed field gel electrophoresis （PFGE）, suggesting that diverse genotypes has been found and no predominant genotype has been detected. Conclusions Ahhough there was no patient ini^eted with legionella was detected in this study, the high prevalence of legionella bacteria in water in public is a potential threaten to the health of the population. It is necessary to strength the surveillance and health supervision on population and central air conditioning system in public.