Grant I R
Department of Food Science (Microbiology), Queen's University, Belfast, N. Ireland, UK.
Acta Vet Scand. 2003;44(3-4):261-6.
The possibility that milk from cattle with Johne's disease could be a potential vehicle of transmission of Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) to humans has been the focus of a UK government-funded research programme at Queen's University, Belfast since 1993. The main findings of this research programme are reported and practical advice about the most appropriate methods for the isolation/detection of this organism in milk is given. The findings of several milk surveys during which optimised sensitive detection methods were employed (decontamination with 0.75% cetyl pyridinium chloride for 5 h prior to culture and a novel immunomagnetic PCR technique) have revealed that detectable levels of M. paratuberculosis are present in bulked raw cows' milk in the UK at both the farm level and at dairy processing plants prior to pasteurisation. Furthermore, results of three different experimental approaches to assess the effect of pasteurisation time/temperature conditions on the viability of M. paratuberculosis (laboratory pasteurisation studies, a national survey of commercially pasteurised milk, and processing of naturally infected milk through commercial-scale pasteurising plant) provide firm evidence that this organism is capable of surviving commercial milk pasteurisation on occasion. Hence, both raw and pasteurised cows' milk are potential vehicles of transmission of M. paratuberculosis to humans.
自1993年以来，患有副结核的奶牛所产牛奶可能成为副结核分枝杆菌向人类传播的潜在载体，这一可能性一直是英国政府资助的贝尔法斯特女王大学研究项目的重点。本文报告了该研究项目的主要发现，并给出了关于牛奶中该微生物最适宜的分离/检测方法的实用建议。在几次牛奶调查中，采用了优化的灵敏检测方法（培养前用0.75%的十六烷基氯化吡啶去污5小时和一种新型免疫磁珠PCR技术），结果显示，在英国，农场层面和巴氏杀菌前的乳制品加工厂的生鲜牛乳中均存在可检测水平的副结核分枝杆菌。此外，三种不同实验方法（实验室巴氏杀菌研究、全国商业巴氏杀菌牛奶调查以及通过商业规模巴氏杀菌厂处理自然感染牛奶）评估巴氏杀菌时间/温度条件对副结核分枝杆菌生存能力影响的结果，提供了确凿证据，表明这种微生物有时能够在商业牛奶巴氏杀菌过程中存活下来。因此，生鲜和巴氏杀菌的牛乳都是副结核分枝杆菌向人类传播的潜在载体。
