Roshani Edirisinghe E A, Anuruddhika Dissanayake D R, Abayasekera Charmalie L, Arulkanthan Appudurai
Department of Veterinary Pathobiology, Centre for Aquatic Animal Disease Diagnosis and Research, Faculty of Veterinary Medicine and Animal Science, University of Peradeniya, Peradeniya, Sri Lanka.
Department of Veterinary Pathobiology, Centre for Aquatic Animal Disease Diagnosis and Research; Department of Veterinary Clinical Science, Faculty of Veterinary Medicine and Animal Science, University of Peradeniya, Peradeniya, Sri Lanka.
Int J Mycobacteriol. 2017 Jul-Sep;6(3):311-314. doi: 10.4103/ijmy.ijmy_88_17.
Nontuberculous mycobacteria (NTM) cause opportunistic infections with increasing frequency in immunocompromised humans. Water is one of the natural sources for transmission of NTM and plays a major role in the epidemiology of NTM infections. This study evaluated the efficacy of calcium hypochlorite and ultraviolet irradiation (UV) to eliminate potentially zoonotic NTM species such as M. marinum and M. fortuitum.
Bacterial suspensions containing1-4 × 105 CFU/ml were exposed to 5, 50, 100, 1,000 and 10,000 mg/L of Ca (OCl)2for 1, 5, 10, 15, 20, 30 and 60 minutes, and 6,000 μW/cm2 UV dose for 5, 10, 20, 30, 60 and 120 seconds.
Of the two methods tested, UV irradiation was more effective than chlorine in achieving three log reduction in viable bacterial count (UV dose 6,000 μW/cm2, exposure time 60 S) as well as in eliminating the organisms (UV dose 17,000 μW/cm2, exposure time: 30 S). When 10,000 mg/L of chlorine was used, 10 and 20 min contact times were required to achieve three log inactivation and complete elimination of M. fortuitum respectively.
Our study suggest that initial disinfection of water by chlorine at the water treatment plant followed by UV irradiation at the household level would minimise the spread of NTM to the susceptible population via drinking water.
非结核分枝杆菌（NTM）在免疫功能低下的人群中引起机会性感染的频率越来越高。水是NTM传播的自然来源之一，在NTM感染的流行病学中起着重要作用。本研究评估了次氯酸钙和紫外线照射（UV）消除潜在人畜共患NTM菌种（如海洋分枝杆菌和偶然分枝杆菌）的效果。
将含有1-4×105CFU/ml的细菌悬液分别暴露于5、50、100、1000和10000mg/L的Ca（OCl）2中1、5、10、15、20、30和60分钟，以及6000μW/cm2的紫外线剂量下5、10、20、30、60和120秒。
在所测试的两种方法中，紫外线照射在使活菌数减少三个对数（紫外线剂量6000μW/cm2，照射时间60秒）以及消除细菌（紫外线剂量17000μW/cm2，照射时间：30秒）方面比氯更有效。当使用10000mg/L的氯时，分别需要10和20分钟的接触时间才能使偶然分枝杆菌实现三个对数的灭活和完全消除。
我们的研究表明，在水处理厂先用氯对水进行初步消毒，然后在家庭层面进行紫外线照射，将最大限度地减少NTM通过饮用水向易感人群的传播。
