ID 原文 译文
52640 This has led to the expansion of cropland and more intense livestock farming near and around cities, increasing opportunities for exposure.  这导致了农田的扩大和城市附近及周边地区更密集的畜牧业，增加了接触和暴露的机会。
52641 Livestock often serve as an epidemiological bridge between wildlife and human infections, such as in the case of avian influenza.  牲畜通常充当野生动植物与人类感染之间的流行病学桥梁，例如禽流感。
52642 Pathogens first circulated in wild birds infected domestic poultry, and were then passed to humans. 病原体首先在野生鸟类中传播，然后感染家禽，最后传染给人类。
52643 Proximity to different species though wet markets or consumption of wild animals can also facilitate animal to human transmission.  通过水产市场接触不同物种或消费野生动物也可能促进病毒从动物向人类的传播。
52644 Early cases of SARS were associated with contact to caged civet cats, being sold in wet markets; and some cases of Ebola in Central Africa are believed to have been transferred from animal to human hosts when infected gorilla meat was consumed. SARS的早期病例就接触了在水产市场贩卖的果子狸。据信，在中非肆虐的埃博拉病例则因食用了受感染的大猩猩肉后，导致病毒从动物转移到人类宿主。
52645 Incubation–the time between human infection and the time when that human presents signs of infection–may last days or weeks; but millions of people, under normal circumstances, travel every day, from one country to another, in just hours.  潜伏期·——从感染到发病的间隔期——可能持续数天或数周。在正常情况下，每天都有数百万人在短短几个小时内从一个国家前往另一个国家旅行。
52646 A disease that originates in one country can quickly spread to others, regardless of the distances between them.  因此，起源于一个国家的疾病可以迅速传播到另一个国家，不论两地的距离相隔多远。
52647 This is particularly visible in the rapid spread of COVID-19, which affected almost every country in the world within three months of the first reported case. 这一点在新冠病毒的传播蔓延中尤为明显，自从报告出现第一例病例到至今，三个月内这一病毒已经遍及世界上几乎每一个国家。
52648 Changes in pathogens 病原体变化
52649 Pathogens change genetically (mutation) as they evolve which allows them to exploit new hosts and survive in new environments.  病原体随着进化而发生遗传变化（突变），这使它们能够利用新宿主并在新环境中生存。