It is caused by the larval stages of the tapeworm Echinococcus multilocularis (EM) whose definitive host is usually the red fox, while arvicolid rodents act as intermediate hosts.
Seda põhjustavad paelussi Echinococcus multilocularis (EM) vastsed, mille peremeesorganismiks on tavaliselt punarebane, kusjuures närilised on vahendavad peremeesorganismid.