Echinococcus multilocularis is a tapeworm responsible for a rare parasitic zoonosis, alveolar echinococcosis. The parasite’s life cycle depends on the predatory relationship between the definitive host (primarily the fox) and the intermediate host (the rodent), as well as on the survival of the parasite’s free-living stage—in the form of oncosphères—in the external environment. In Europe, an increase in fox populations has been observed concurrently with the expansion of the parasite’s range. At the same time, prevalence rates in foxes have risen in historically contaminated regions. In France, the westward expansion of the known endemic zone has been demonstrated, with positive cases reported in the departments of Manche and Calvados. The presence of foxes in urban areas enables the establishment of the Echinococcus multilocularis life cycle. However, the prevalence rates observed in urban areas are very low compared to rural areas. Domestic animals (dogs, cats) can also participate in the life cycle as definitive hosts and, due to their proximity to humans, may serve as a potential source of infection. Regular deworming with praziquantel is recommended in endemic areas. The expansion of the known endemic range of Echinococcus multilocularis in both Europe and France, as well as the increase in fox prevalence in historical foci, raises concerns about a future increase in the number of human cases. (R.A.)