Pathogenic organisms exert a negative impact on host health, revealed by the clinical signs of infectious diseases. Immunity limits the severity of infectious diseases through resistance mechanisms that sense and target pathogens for containment, killing, or expulsion. These resistance mechanisms are viewed as the prevailing function of immunity. Under pathophysiologic conditions, however, immunity arises in response to infections that carry health and fitness costs to the host. Therefore, additional defense mechanisms are required to limit these costs, before immunity becomes operational as well as thereafter to avoid immunopathology. These are tissue damage control mechanisms that adjust the metabolic output of host tissues to different forms of stress and damage associated with infection. Disease tolerance is the term used to define this defense strategy, which does not exert a direct impact on pathogens but is essential to limit the health and fitness costs of infection. Under this argument, we propose that disease tolerance is an inherent component of immunity.

中文翻译：

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疾病耐受性是免疫力的固有组成部分。

感染性疾病的临床体征表明，病原性生物会对宿主健康产生负面影响。免疫力通过抵抗力机制限制传染病的严重程度，这种抵抗力机制可以感应和靶向病原体以进行遏制，杀灭或驱逐。这些抵抗机制被认为是免疫的主要功能。然而，在病理生理条件下，免疫反应是对宿主的健康和适应性成本造成感染的反应。因此，在免疫开始起作用之前以及之后避免免疫病理学，需要额外的防御机制来限制这些成本。这些是组织损伤控制机制，其调节宿主组织的代谢输出以适应与感染相关的不同形式的压力和损伤。疾病耐受性是用于定义此防御策略的术语，它不会对病原体产生直接影响，但对于限制感染的健康和适应性成本至关重要。根据这一论点，我们认为疾病耐受性是免疫力的固有组成部分。