For representing the above functional covariates, a B–spline basis of five components was used in all cases (based on the previous experience of the authors with this type of data). The prediction for the overall influenza rate is constructed by appropriately aggregating the predictions of the s regions that are made independently, i.e. the estimation of β and ϕ are made only with the data of that county. Fig 1 shows the overall influenza rate that normally grows in the late autumn and reaches a peak at the beginning of the calendar year. These plots clearly show the large difference between reported influenza cases in winter and summer. The influenza rate for each county shows a similar pattern but with small differences in the peak epidemic period. We downloaded meteorological data from the regional Weather Service of Galicia (http://www.meteogalicia.es/). S1 Appendix describes the supplementary material (functions, libraries, source data and code) and S1 File contains the code and dataset used in this study.