Ogden N H, AbdelMalik P, Pulliam Jrc
Public Health Risk Sciences Division, National Microbiology Laboratory, Public Health Agency of Canada, Saint-Hyacinthe, QC.
Field Service Training and Response, Health Security Infrastructure Branch, Public Health Agency of Canada, Ottawa, ON.
Can Commun Dis Rep. 2017 Oct 5;43(10):206-211. doi: 10.14745/ccdr.v43i10a03.
Emerging infectious diseases (EIDs), including West Nile virus, severe acute respiratory syndrome (SARS) and Lyme disease, have had a direct effect within Canada, while many more EIDs such as Zika, chikungunya and Ebola are a threat to Canadians while travelling. Over 75% of EIDs affecting humans are, or were originally, zoonoses (infectious diseases transmitted from animals to humans). There are two main ways by which infectious diseases can emerge: by changes in their geographical ranges and by adaptive emergence, a genetic change in a microorganism that results in it becoming capable of invading a new niche, often by jumping to a new host species such as humans. Diseases can appear to emerge simply because we become capable of detecting and diagnosing them. Management of EID events is a key role of public health globally and a considerable challenge for clinical care. Increasingly, emphasis is being placed on predicting EID occurrence to "get ahead of the curve" - that is, allowing health systems to be poised to respond to them, and public health to be ready to prevent them. Predictive models estimate where and when EIDs may occur and the levels of risk they pose. Evaluation of the internal and external drivers that trigger emergence events is increasingly considered in predicting EID events. Currently, global changes are driving increasing occurrence of EIDs, but our capacity to prevent and deal with them is also increasing. Web-based scanning and analysis methods are increasingly allowing us to detect EID outbreaks, modern genomics and bioinformatics are increasing our ability to identify their genetic and geographical origins, while developments in geomatics and earth observation will enable more real-time tracking of outbreaks. EIDs will, however, remain a key, global public health challenge in a globalized world where demographic, climatic, and other environmental changes are altering the interactions between hosts and pathogen in ways that increase spillover from animals to humans and global spread.
新发传染病（EIDs），包括西尼罗河病毒、严重急性呼吸综合征（SARS）和莱姆病，已在加拿大境内产生直接影响，而更多的新发传染病，如寨卡病毒、基孔肯雅热和埃博拉病毒，则在加拿大人旅行时对其构成威胁。超过75%的影响人类的新发传染病是或原本就是人畜共患病（从动物传播给人类的传染病）。传染病出现的主要途径有两种：一是其地理范围发生变化，二是适应性出现，即微生物发生基因变化，使其能够侵入新的生态位，通常是通过跳到新的宿主物种，如人类。疾病看似出现可能仅仅是因为我们有能力检测和诊断它们。新发传染病事件的管理是全球公共卫生的关键职责，也是临床护理面临的巨大挑战。越来越多的重点放在预测新发传染病的发生上，以“抢在曲线前面”——也就是说，使卫生系统做好应对准备，公共卫生做好预防准备。预测模型估计新发传染病可能出现的地点和时间以及它们所构成的风险水平。在预测新发传染病事件时，越来越多地考虑对引发出现事件的内部和外部驱动因素进行评估。目前，全球变化导致新发传染病的发生日益增多，但我们预防和应对它们的能力也在提高。基于网络的扫描和分析方法越来越使我们能够检测新发传染病疫情，现代基因组学和生物信息学提高了我们识别其基因和地理起源的能力，而地理信息学和地球观测的发展将使我们能够更实时地追踪疫情。然而，在一个全球化的世界里，新发传染病仍将是一项关键的全球公共卫生挑战，在这个世界中，人口、气候和其他环境变化正在改变宿主与病原体之间的相互作用，增加了从动物到人类的溢出以及全球传播。
