Hydatid Disease

Hydatid disease is a zoonosis in which humans become the accidental host to the larval stage of Echinococcus granulosus, also known as the dog tapeworm. Occurring worldwide, the natural lifecycle of E. granulosus tapeworms consists of a canid definitive host for the adult tapeworm stage, and an herbivorous animal (sheep, in most cases) intermediate host for the tissueinvasive and cyst-forming larval stage. Dogs and other canids harboring gut-resident tapeworms readily transmit the tapeworm eggs (and subsequent formation of larval cysts) to humans in close contact with them. It is this author's experience that adoption of indigenous dogs as "camp mascots" is a common tradition in the military deployed setting. This practice puts troops in danger of acquiring hydatid disease. The U.S. Veterans Health Ad-ministration 2025 report on echinococcosis in Veterans states there were 1,059 diagnoses of the disease in their system from 2000 to 2024. In addition, deployed healthcare practitioners should include hydatid disease in the differential diagnosis of host-country nationals presenting with spaceoccupying lesions and/or anaphylaxis of uncertain etiology.