A mechanistic spatio-temporal framework for modelling individual-to-individual transmission-With an application to the 2014-2015 West Africa Ebola outbreak

PLoS Comput Biol. 2017 Oct 30;13(10):e1005798. doi: 10.1371/journal.pcbi.1005798. eCollection 2017 Oct.

Abstract

In recent years there has been growing availability of individual-level spatio-temporal disease data, particularly due to the use of modern communicating devices with GPS tracking functionality. These detailed data have been proven useful for inferring disease transmission to a more refined level than previously. However, there remains a lack of statistically sound frameworks to model the underlying transmission dynamic in a mechanistic manner. Such a development is particularly crucial for enabling a general epidemic predictive framework at the individual level. In this paper we propose a new statistical framework for mechanistically modelling individual-to-individual disease transmission in a landscape with heterogeneous population density. Our methodology is first tested using simulated datasets, validating our inferential machinery. The methodology is subsequently applied to data that describes a regional Ebola outbreak in Western Africa (2014-2015). Our results show that the methods are able to obtain estimates of key epidemiological parameters that are broadly consistent with the literature, while revealing a significantly shorter distance of transmission. More importantly, in contrast to existing approaches, we are able to perform a more general model prediction that takes into account the susceptible population. Finally, our results show that, given reasonable scenarios, the framework can be an effective surrogate for susceptible-explicit individual models which are often computationally challenging.

MeSH terms

  • Africa, Western / epidemiology
  • Computer Simulation
  • Disease Outbreaks / statistics & numerical data*
  • Disease Transmission, Infectious / statistics & numerical data*
  • Geographic Information Systems / statistics & numerical data
  • Hemorrhagic Fever, Ebola / epidemiology*
  • Hemorrhagic Fever, Ebola / transmission*
  • Humans
  • Models, Statistical*
  • Prevalence
  • Proportional Hazards Models
  • Risk Assessment / methods
  • Spatio-Temporal Analysis*