The goal of epiquest is to compute quantile epidemic state (QUEST) thresholds, developed in 2025 at Sciensano, the Belgian Institute for Health.
While other methods for thresholds of respiratory surveillance signals aim to classify seasonal intensity, allowing for comparison between seasons, the QUEST thresholds were developed to do week-to-week surveillance of the epidemiogical situation. A central objective during development was to ensure these thresholds were easy to interpret and directly relevant to monitoring the burden of respiratory pathogens on the healthcare system.
In short, the method uses a hidden Markov model to define the epidemic state and defines thresholds as specific quantiles of observed epidemic state incidences.
If you are new to the QUEST methodology, we recommend starting with our primary guides:
You can install the development version of epiquest from GitHub as follows.
# install.packages("pak")
pak::pkg_install("sciensanogit/epiquest")