Ecology. 2014 Apr;95(4):817-32. doi: 10.1890/13-1041.1.
Control of human infectious disease has been promoted as a valuable ecosystem service arising from the conservation of biodiversity. There are two commonly discussed mechanisms by which biodiversity loss could increase rates of infectious disease in a landscape. First, loss of competitors or predators could facilitate an increase in the abundance of competent reservoir hosts. Second, biodiversity loss could disproportionately affect non-competent, or less competent reservoir hosts, which would otherwise interfere with pathogen transmission to human populations by, for example, wasting the bites of infected vectors. A negative association between biodiversity and disease risk, sometimes called the "dilution effect hypothesis," has been supported for a few disease agents, suggests an exciting win-win outcome for the environment and society, and has become a pervasive topic in the disease ecology literature. Case studies have been assembled to argue that the dilution effect is general across disease agents. Less touted are examples in which elevated biodiversity does not affect or increases infectious disease risk for pathogens of public health concern. In order to assess the likely generality of the dilution effect, we review the association between biodiversity and public health across a broad variety of human disease agents. Overall, we hypothesize that conditions for the dilution effect are unlikely to be met for most important diseases of humans. Biodiversity probably has little net effect on most human infectious diseases but, when it does have an effect, observation and basic logic suggest that biodiversity will be more likely to increase than to decrease infectious disease risk.
控制人类传染病已被宣传为保护生物多样性所带来的有价值的生态系统服务。生物多样性丧失可能会增加景观中传染病发病率的两种常见机制。首先，竞争者或捕食者的丧失可能会促进有能力的储存宿主数量的增加。其次，生物多样性的丧失可能会不成比例地影响非竞争或能力较低的储存宿主，否则这些宿主会通过例如浪费受感染媒介的叮咬来干扰病原体向人类传播。生物多样性与疾病风险之间的负相关关系，有时被称为“稀释效应假说”，已经得到了一些疾病病原体的支持，这为环境和社会带来了令人兴奋的双赢局面，并已成为疾病生态学文献中的一个普遍话题。已经进行了案例研究来论证稀释效应在疾病病原体中是普遍存在的。不太引人注目的是，在一些情况下，生物多样性的增加不会影响或增加对公共卫生关注的病原体的传染病风险。为了评估稀释效应的普遍程度，我们在广泛的人类疾病病原体范围内审查了生物多样性与公共卫生之间的关联。总体而言，我们假设对于大多数人类重要疾病来说，稀释效应的条件不太可能得到满足。生物多样性可能对大多数人类传染病的影响不大，但当它确实有影响时，观察和基本逻辑表明，生物多样性更有可能增加而不是降低传染病的风险。
