Casadevall Arturo, Pirofski Liise-anne
Ann Med. 2002;34(1):2-4. doi: 10.1080/078538902317338580.
The question 'what is a pathogen?' derives from pathogen-centered views of microbial pathogenesis that invoke microbial characteristics to explain virulence. However, virulence cannot be an independent microbial variable since it is only expressed in a susceptible host. Hence, the question 'what is a pathogen?' cannot be separated from the question 'what is a host?' Given that virulence is an outcome of the host-microbe interaction that is not invariant from host to host, neither the pathogen or the host can be defined independently. To sidestep this paradox, one can focus on the outcome of the interaction using host damage as the common denominator to define and explain the various outcomes that can result from the host-microbe interaction. Using this concept a pathogen is defined as a microbe capable of causing host damage.
“什么是病原体？”这个问题源自以病原体为中心的微生物致病观点，这种观点援引微生物特征来解释毒力。然而，毒力不可能是一个独立的微生物变量，因为它仅在易感宿主中表现出来。因此，“什么是病原体？”这个问题无法与“什么是宿主？”这个问题分开。鉴于毒力是宿主 - 微生物相互作用的结果，且在不同宿主之间并非一成不变，所以病原体和宿主都不能独立定义。为了避开这个悖论，可以将重点放在相互作用的结果上，以宿主损伤作为共同标准来定义和解释宿主 - 微生物相互作用可能产生的各种结果。基于这一概念，病原体被定义为能够造成宿主损伤的微生物。
