Kilesas are like birds. They can be seen all over the world. But they are not evenly distributed. There are places where they congregate: estuaries, woodland, fish markets, municipal dumps,Trafalgar Square, bird tables, cliffs. The dedicated bird watcher comes to recognise this.
It is the same with diseases. Some locations attract them and they congregate there: garbage dumps, sewers, contaminated water, battle fields, schools, Derriford Hospital.
It is the same with kilesas. Some locations attract them and they congregate there. Pubs, football matches, gambling casinos, night clubs, universities. Also some activities; professional sport (the more money involved, the more kilesas), politics (the more money the more kilesas), drug and alcohol abuse. Some ways of life; hunting, theft, prostitution. Some careers; vivisectionists, arms dealing, slaughterhousemen, factory farming, mercenaries.
NEW PROJECT: AN INTENSIVE COURSE IN KILESA SPOTTING
(Bird watchers spend a lot of time poring over books which give detailed descriptions of birds so that when they go out spotting, they can easily identify them).