The Legionella Spp Contamination In Hospital Water Supply System And Its Detection Research

[Background] :In 1970', when Amercian had broken out the Legionnairs' Disease (LD),there are many reports about LD in a lot of countries. In 1982, NanJing approved the LD for the first time. More and more evidences showed the relationship between LD and water contaminated with Legionella. Our research is aimed to evaluate the Legionella contamination in Zhongshan Hospital ,collect the data epidemic and establish the way of Legionella detection in contaminated water.[Objective] :1.To explore the contamination by Legionella in water supply system in Zhongshan Hospital. 2.Use PCR assay to identify the Legionella. 3. To investigate the affection to the proliferation of Legionella by different periods of acidation and evaluate clinical practicality.[Methods] : 1.52 samples from tap of water supply system in 27 wards of the hospital were collected and cultivated for Legionella. 2.We use two primers 5srRNA and mip to approve the legionella.3. Pickling agent (pH2.2) was added into the equivalent volume of bacterial suspension of Legionella Pneumonphilia (LP1). The compounds were inoculated into GVPC plates after placing for various time. Colony count was used to compare the affection to the proliferation of Legionella and mixture of Legionella pneumonphilia and Pseudomonas aeruginosa by different periods of acidation. Meanwhile, inhibition to Pseudomonas aeruginosa by pickling agent was also observed.[Results] : 1.12 out of 52 samples(23.1%), 9 out of 27 wards(33.3%) were positive for Legionella.2. All strains were positive for Legionella DNA and negative for Legionella pneumonia DNA. 3. The proliferation of Legionella Pneumonphilia was less affected by acidation for 3 to 5 mins in bacterial suspension of LP1 as well as in the mixure of Legionella pneumonphilia and Pseudomonas aeruginosa. As to the mixture, contaminated bacteria can be inhibited by acidation for 3 to 15 mins.[Conclusions] : 1 .The water supply system in the Zhongshan hospital is contaminated by Legionella seriously. Corresponding preventive and control measures should be formulated to prevent Legionnaires' disease outbreak. 2. Appropriate period of acidation had little affection to the proliferation of Legionella and inhibited the contaminated bacteria, which improved the detection rate of Legionella effectively. However, the rate would be reduced if the period of acidation was too long.