Dangerous Tapeworm Detected in Pacific Northwest Wildlife for First Time
A potentially dangerous tapeworm has been detected for the first time in wild animals on the U.S. West Coast. The parasite, Echinococcus multilocularis, was found in 37% of coyotes tested around Puget Sound in the Pacific Northwest—a rate that surprised researchers given the region's lack of prior reports.
The tapeworm is associated with alveolar echinococcosis, a serious condition that can cause tumor-like lesions in the liver and spread to other organs. While human infections remain rare, the disease is considered potentially fatal if left untreated and can take years to develop symptoms.
Coyotes and other canids serve as the parasite's primary hosts, while small mammals like rodents typically carry the larval form. Humans can become accidental hosts by ingesting eggs shed in the feces of infected animals.
The discovery suggests the tapeworm may be spreading across the continent more rapidly than previously understood. Health officials recommend that residents in affected areas avoid handling wild canids and practice good hygiene, particularly when gardening or working in areas where wildlife is present.