Ud over smitten fra moderen er der overførelsen fra marker, græsgange, hø og som det er tilfældet for scrapie, vil vi stå med marker, hvor prion inkystereres og vender tilbage, så snart man sætter kvæg ud.
In addition to maternal contamination, there may be transmission via the fields, the grazing land, the grass, and there may be badlands, as in the case of ovine scrapie, where the prion would be encysted and would return as soon as bovine animals were put to pasture there.