1. Cambridge Richard Stutt University Nik Cunniffe Erik DeSimone Matt Castle Chris Gilligan RothamstedStephen Parnell ResearchFrank van den Bosch May 2012

3.  Model must integrate ◦ Location of hosts ◦ Environmental drivers ◦ Pathogen dispersal  Compartmental model

4.  250m x 250m resolution  Combine data on  Larch  Rhododendron  Vaccinium  NIWT (other tree hosts)  Weight host types by sporulation/susceptibility

5.  Pathogen responds to temperature/moisture  Model underlying suitability for each location  Statistical climate model then used to predict future fluctuations about this

6.  Dispersal kernel describes pathogen spread  Implicitly incorporates many mechanisms Positive Negative

7.  Spread in the absence of control  Effect of extent of control ◦ Felling infected stands ◦ Felling infected stands + proactive control  Surveying for P. Ramorum on heathland

11. Hazard map + known infections = sampling pattern

12.  Continuous model improvement (data driven)  Region specific control  Effect of non compliance  Transition strategies  User friendly models

13.  Forestry Commission ◦ Bruce Rothnie ◦ Joan Webber  FERA ◦ Keith Walters ◦ Phil Jennings ◦ Judith Turner ◦ Kate Somerwill  Funding from DEFRA, BBSRC and USDA

15.  Susceptible hosts in the landscape are divided into a metapopulation at a chosen resolution (250m)  UK Sudden Oak death landscape assembled from: ◦ National Inventory of Woodland Trees (NIWT) ◦ Forestry Commission commercial Larch data ◦ Maximum Entropy suitability models for Rhododendron and Vaccinium (FERA/JNCC)  Different hosts have different weightings for sporulation and susceptibility

16. Broadleaved Young TreesFelled Coniferous

17.  Identify favourable conditions for P. ramorum ◦ moisture ◦ temperature  Parameterise using experimental results Relative Sporulation Temperature

18.  Fit model using historic spread data  Used Maximum Likelihood to assess goodness of fit  Predicted probability of infection by 2010 given starting conditions in 2004 Survey Positive for P. ramorum Survey Negative for P. ramorum

24. Total Infection Symptomatic Symptomatic at time of Survey

25. Total Infection Symptomatic Symptomatic at time of Survey

26. Total Infection Symptomatic Symptomatic at time of Survey

27. Total Infection Symptomatic Symptomatic at time of Survey

29. Examine region of South Wales

30. Cull: no delay after survey 6 month delay

31.  Key Questions When Surveying for Disease: ◦ Where is the disease likely to be? ◦ Where is it likely to be most severe and spread most rapidly? ◦ How to optimise the sampling?

32.  Uses: Currently known outbreaks Predicted severity of outbreaks => Sampling weighting  Survey pattern formed => sampling from weightings  Map shows a weighting and a set of survey points (green)