Clifford Charles B, Watson Julie
Charles River Laboratories, 251 Ballardvale Street, Wilmington, MA 01887, USA.
ILAR J. 2008;49(3):291-302. doi: 10.1093/ilar.49.3.291.
Although some previously common infections, such as Sendai virus and Mycoplasma pulmonis, have become rare in laboratory rodents in North American research facilities, others continue to plague researchers and those responsible for providing biomedical scientists with animals free of adventitious disease. Long-recognized agents that remain in research facilities in the 21st century include parvoviruses of rats and mice, mouse rotavirus, Theilers murine encephalomyelitis virus (TMEV), mouse hepatitis virus (MHV), and pinworms. The reasons for their persistence vary with the agent. The resilience of parvoviruses, for example, is due to their resistance to inactivation, their prolonged shedding, and difficulties with detection, especially in C57BL/6 mice. Rotavirus also has marked environmental resistance, but periodic reintroduction into facilities, possibly on bags of feed, bedding, or other supplies or equipment, also seems likely. TMEV is characterized by resistance to inactivation, periodic reintroduction, and relatively long shedding periods. Although MHV remains active in the environment at most a few days, currently prevalent strains are shed in massive quantities and likely transmitted by fomites. Pinworm infestations continue because of prolonged infections, inefficient diagnosis, and the survivability of eggs of some species in the environment. For all of these agents, increases in both interinstitutional shipping and the use of immunodeficient or genetically modified rodents of unknown immune status may contribute to the problem, as might incursions by wild or feral rodents. Elimination of these old enemies will require improved detection, strict adherence to protocols designed to limit the spread of infections, and comprehensive eradication programs.
尽管一些以前常见的感染，如仙台病毒和肺支原体，在北美研究机构的实验啮齿动物中已变得罕见，但其他感染仍继续困扰着研究人员以及那些负责为生物医学科学家提供无外源性病原体动物的人。在21世纪仍存在于研究机构中的长期被认可的病原体包括大鼠和小鼠的细小病毒、小鼠轮状病毒、泰勒氏鼠脑脊髓炎病毒（TMEV）、小鼠肝炎病毒（MHV）和蛲虫。它们持续存在的原因因病原体而异。例如，细小病毒的持久性归因于其对灭活的抵抗力、长时间的排毒以及检测困难，尤其是在C57BL/6小鼠中。轮状病毒也具有显著的环境抵抗力，但也可能通过饲料袋、垫料或其他用品或设备等定期重新引入设施中。TMEV的特点是对灭活有抵抗力、定期重新引入以及排毒期相对较长。尽管MHV在环境中最多只能存活几天，但目前流行的毒株大量排毒，很可能通过污染物传播。蛲虫感染持续存在是因为感染时间长、诊断效率低以及某些种类的虫卵在环境中的生存能力。对于所有这些病原体，机构间运输的增加以及使用免疫缺陷或免疫状态未知的基因改造啮齿动物可能会导致问题，野生或野生啮齿动物的入侵也可能如此。消除这些老对手需要改进检测、严格遵守旨在限制感染传播的方案以及全面的根除计划。
