There were 118 cases of bovine spongiform encephalopathy (<scp>bse</scp>) in Belgium before January 1, 2004. Trends in their age at detection were analysed and attempts were made to use this parameter as a predictor of the current status of the <scp>bse</scp> epidemic in the country. The following variables were considered: date of birth, breed, date of detection, mode of detection, and the number and age of animals slaughtered and rendered each month. Age at detection as a function of date of birth was a very poor epidemiological indicator. It was concluded that the increasing age of <scp>bse</scp> cases when they were detected was due to the depletion of cases, as a result of there being no new infections, and that it is a reliable indicator of a decrease in the epidemic curve in Belgium. By means of a simulation it is shown how age distribution at the time of detection closely follows the epidemic curve and data from Great Britain are used to illustrate the point.