Ostfeld R S
Cary Institute of Ecosystem Studies, Millbrook, NY 12545, USA.
Clin Microbiol Infect. 2009 Jan;15 Suppl 1:40-3. doi: 10.1111/j.1469-0691.2008.02691.x.
The unprecedented loss of biological diversity from anthropogenic causes has profound impacts on human health. One way that biodiversity loss threatens human health is by exacerbating risk and incidence of infectious diseases. This paper briefly reviews two zoonotic diseases--West Nile virus (WNV) illness and Lyme disease (LD)--in which high diversity in the community of vertebrate hosts for arthropod vectors strongly reduces human risk. In both cases, the primary reservoirs for the pathogen are species that dominate in human-impacted, low-diversity communities. As a result, the generalist vectors responsible for transmitting the pathogens to humans have relatively high feeding rates on these reservoirs, leading to high infection prevalence in mosquito (for WNV) and tick (for LD) vectors. In contrast, where native vertebrate diversity is high, mosquito and tick vectors evidently feed from a wider variety of hosts, most of which are poor reservoirs for the pathogens, resulting in lower infection prevalence. Protection of humans against exposure to zoonotic pathogens should be added to the list of utilitarian functions provided by high biodiversity.
人为因素导致的前所未有的生物多样性丧失对人类健康产生了深远影响。生物多样性丧失威胁人类健康的一种方式是加剧传染病的风险和发病率。本文简要回顾了两种人畜共患疾病——西尼罗河病毒（WNV）病和莱姆病（LD），在这两种疾病中，节肢动物媒介的脊椎动物宿主群落的高度多样性极大地降低了人类感染风险。在这两种情况下，病原体的主要宿主都是在受人类影响的低多样性群落中占主导地位的物种。因此，负责将病原体传播给人类的通才媒介在这些宿主上的摄食率相对较高，导致蚊子（对于西尼罗河病毒）和蜱虫（对于莱姆病）媒介的感染率很高。相比之下，在本地脊椎动物多样性较高的地方，蚊子和蜱虫媒介显然以更多种类的宿主为食，其中大多数宿主是病原体的不良宿主，从而导致较低的感染率。保护人类免受人畜共患病原体的接触，应被列入高生物多样性所提供的功利功能清单之中。
