Welcome to the HUGIN IFR VUW / BIOTRACER extension activity. For more information on BIOTRACER visit project home page or

This website will feature dissemination of the milk biotracing model described in [1].

This web site demonstrates a probabilistic model that quantifies hazards that arise from Staphylococcus aureus in milk that is sold as pasteurized in the United Kingdom. The model is centered on coupled dynamics for S. aureus populations, staphylococcal enterotoxins, and the concentration of alkaline phosphatase throughout the milk chain. On this web site the user has the possibility to repeat (some of) the results reported in [1] using an online interface to the domain modelling tools used (HUGIN, see e.g.,

The website has five sections.

  1. Biotracing for Dummies gives an introduction to the concept of biotracing. It describe the process of performing a biotrace using probabilistic graphical models.
  2. Biotracing for Experts describes in detail a real world biotracing system based on probabilistic graphical models.
  3. Operational Biotracing demonstrates a real world biotracing system.
  4. Biotracing on a Mobile demonstrates the real world biotracing system on a mobile device.
  5. Short introduction to Bayesian modelling using the Restaurant Bayes example.

For more information on the BIOTRACER project visit the project web-site.


[1] G. C. Barker and N. Gomez-Tome (2011). A Risk Assessment Model for Enterotoxigenic Staphylococcus aureus in Pasterurized Milk: A Potential Route to Source-Level Inference. Risk Analysis. doi: 10.1111/j.1539-6924.2011.01667.x