Is this outbreak over?

Motivation At which time point during an outbreak of a person-to-person transmitted disease can one declare the outbreak as having ended? Answering this question can be important in order to calm the population, re-attract tourists, stop export bans or reduce alertness status. The current WHO method for answering the above question is as follows: a period of two times the longest possible incubation time needs to pass without observing additional cases, before the outbreak can be declared as being over. ...

practicals

Ebola simulation part 2: outbreak reconstruction

#genetics #simulation #response #outbreaker2 #epicurve #reproduction number

This practical is the second part of the response to a simulated Ebola Virus Disease (EVD) outbreak taking place in the city of Ankh, Republic of Morporkia. While the first part focussed on early assessments of transmissibility, this part explores more methodological options for estimating transmissibility, and provides an introduction to outbreak reconstruction using outbreaker2. An update on the EVD outbreak in Ankh, Republic of Morporkia After some rather concerning preliminary results on the new EVD outbreak in the city of Ankh, Republic of Morporkia, Public Health Morporkia (PHM) has sent you updates of the linelists and contact data. ...

Ebola simulation part 1: early outbreak assessment

#simulation #response #Ebola #epicurve #reproduction number

This practical simulates the early assessment and reconstruction of an Ebola Virus Disease (EVD) outbreak. It introduces various aspects of analysis of the early stage of an outbreak, including contact tracing data, epicurves, growth rate estimation from log-linear models, and more refined estimates of transmissibility. A follow-up practical will provide an introduction to transmission chain reconstruction using outbreaker2. A novel EVD outbreak in Ankh, Republic of Morporkia A new EVD outbreak has been notified in the small city of Ankh, located in the Northern, rural district of the Republic of Morporkia. ...

VBD: building a simple model for Zika

#zika #compartmental models

This practical aims to illustrate the basics of vector borne disease (VBD) modelling using R, with an emphasis on how the methods work. We will use a basic model for an arboviral infection as an example. In this practical we will begin by gaining some understanding of the components which contribute to R0 and how potential interventions influence transmission. Later in the practical you will construct a model of Zika transmission to look at the effects of several parameters. ...

Ebola: building few models for Ebola

#Ebola #compartmental models

This practical aims to illustrate the basics of Ebola modelling using R, with an emphasis on how the method works. We will start with a basic model for Ebola. We will then illustrate how to account for an evolving context, e.g. implementation of control measures. Finally, we will explore basic principle of model fitting. Core Concepts From the previous lecture, we will further develop these concepts: Compartmental models Flow diagrams and writing down a model Natural history of Ebola Control strategies Introduction to model fitting Required packages install. ...

Phylogenetic tree reconstruction

#genetics

This practical aims to illustrate the basics of phylogenetic reconstruction using R, with an emphasis on how the methods work, how their results can be interpreted, and the relative advantages and limitations of the methods. Three main classes of phylogenetic approaches are introduced, namely distance-based, maximum parsimony, and maximum likelihood methods. We also illustrate how to assess the reliability of individual nodes using bootstrap, and show how a simple linear model can be used to estimate a molecular clock in rooted phylogenies. ...