/dame-gideon

🌍 💉 Why do countries share pathogens? 💉 🌍

Primary LanguageR

Socioecological similarity and connectivity predicts the global biogeography of infectious disease

The goal of this project is to come up with a reasonable way to predict pathogen sharing patterns between countries, using the DAME (dynamic additive and multiplicative effects model) for dyadic networks.

This follows on two previous preprints:

  1. Poisot, T., Nunn, C., & Morand, S. (2014). Ongoing worldwide homogenization of human pathogens. bioRxiv, 009977.
  2. Dallas, T. A., Carlson, C. J., & Poisot, T. (2018). Leveraging pathogen community distributions to understand outbreak and emergence potential. bioRxiv, 336065.

The GIDEON data is available as a list of countries, years, and pathogens. The goal is currently to come up with appropriate dyadic predictors for pairs of countries.

What questions are we asking?

  • Can we appropriately describe pathogen geography?
  • Which predictors work best overall?
  • Do different predictors work better for different agents (bacterial, viral, fungal, protozoan)?
  • Do different predictors work better for different transmission routes (zoonotic, vector-borne)?
  • Are there any detectably-weird years?
  • Are there any detectably-weird country associations?
  • What does this teach us about forecasting disease emergence?

Designing an appropriate predictor set

So far there are three categories that broadly include a few different ideas, which draw on a few specific data sources very heavily:

Geographic predictors

  1. Geographic distance between countries: several options available in GeoDist
  • dist: distance between most important cities
  • distcap: distance between capital cities
  • distw: distance weighted by population (gravity model)
  • distwces: distance weighted by population (gravity model, usually used for bilateral trade flow)
  1. Contiguity between countries (shared border)
  • contig in GeoDist (a binary variable)
  1. Shared continent
  • can be derived from continent in GeoDist

Social predictors

  1. Shared language
  • can derive from GeoDist either for official language, or language spoken by more than 9% of the population
  1. Shared colonial history: a few options in GeoDist
  • comcol: common colonizer after 1945
  • colony: have ever had a colonial link
  • curcol: currently in a colonial relationship
  1. Traveler data
  • flight data? Shweta could help design this part I think
  1. Trade data?
  • Bomin included some in the original DAME paper that I think would work nicely here, probably

Ecological predictors

  1. Dissimilarity in wildlife community (GBIF)
  • all vertebrates?
  • all mammals
  • key mammal groups: bats, primates, rodents
  • use Jaccard dissimilarity like Dallas et al.
  1. Dissimilarity in vector community
  1. Climatic dissimilarity
  1. Number of shared invasive species