A mixed-model approach to analysis of larval raccoon roundworm (Baylisascaris procyonis) prevalence in suburban small mammal populations, focused on how prevalence is related to human population density. Prevalence of infection (logistic) and infection intensity (Poisson-lognormal) are modeled simultaneously.

The results are published in the following article:

Kellner, Kenneth F.; Page, L. Kristen; Downey, Mark; McCord, Sarah E. 2012. Effects of urbanization on prevalence of Baylisascaris procyonis in intermediate host populations. Journal of Wildlife Diseases 48:1083-1087


The analysis_bp_im_prev.R file contains the analysis described above implemented in JAGS (the original publication version used WinBUGS). Additional information is provided in the comments of the file. The model in the BUGS language is contained in the file model_bp_im_prev.R.

A sample of the original dataset used for this analysis is contained the file sample_bp_im_prev.csv. Each row is an individual mouse captured and sampled for larval raccoon roundworm infection. The columns in the dataset are described below.

  1. year07 - Study year; if 1, the mouse was captured in 2007, 0 if captured in 2006.
  2. sex - Sex of the mouse; 1 if male and 0 if female.
  3. mass - Mass in grams of the mouse at time of capture.
  4. dens - Human population density (persons/km2) around capture site.
  5. positive - Infection status; 1 if infected 0 if not.
  6. burden - Number of roundworms collected from mouse after digestion.