Egan Joseph R, Hall Ian M
J R Soc Interface. 2015 May 6;12(106). doi: 10.1098/rsif.2015.0096.
Back-calculation is a process whereby generally unobservable features of an event leading to a disease outbreak can be inferred either in real-time or shortly after the end of the outbreak. These features might include the time when persons were exposed and the source of the outbreak. Such inferences are important as they can help to guide the targeting of mitigation strategies and to evaluate the potential effectiveness of such strategies. This article reviews the process of back-calculation with a particular emphasis on more recent applications concerning deliberate and naturally occurring aerosolized releases. The techniques can be broadly split into two themes: the simpler temporal models and the more sophisticated spatio-temporal models. The former require input data in the form of cases' symptom onset times, whereas the latter require additional spatial information such as the cases' home and work locations. A key aspect in the back-calculation process is the incubation period distribution, which forms the initial topic for consideration. Links between atmospheric dispersion modelling, within-host dynamics and back-calculation are outlined in detail. An example of how back-calculation can inform mitigation strategies completes the review by providing improved estimates of the duration of antibiotic prophylaxis that would be required in the response to an inhalational anthrax outbreak.
反向推算是一种过程，通过该过程可以实时或在疾病爆发结束后不久推断出导致疾病爆发的事件中通常不可观察的特征。这些特征可能包括人员暴露的时间和爆发源。此类推断很重要，因为它们有助于指导缓解策略的目标设定，并评估这些策略的潜在有效性。本文回顾了反向推算的过程，特别强调了有关故意和自然发生的气溶胶释放的最新应用。这些技术大致可分为两个主题：较简单的时间模型和更复杂的时空模型。前者需要以病例症状出现时间的形式输入数据，而后者需要额外的空间信息，如病例的家庭和工作地点。反向推算过程中的一个关键方面是潜伏期分布，这是首先要考虑的主题。详细概述了大气扩散模型、宿主内动态和反向推算之间的联系。通过提供对吸入性炭疽爆发应对中所需抗生素预防持续时间的改进估计，一个反向推算如何为缓解策略提供信息的例子完成了本次综述。
