Alaskan salmon infected with Japanese tapeworm, CDC warns

The Japanese broad tapeworm has been identified in Alaskan-caught salmon, according to a new report from the Centers for Disease Control, providing a good reason to think twice before eating any raw fish. The parasite, known as Diphyllobothrium nihonkaiense, has been cited as responsible for about 2,000 cases of known human infections, the vast majority of them in Japan, South Korea, and similar regions.

According to the CDC, researchers found the presence of the Japanese broad tapeworm in salmon caught in and imported from the Pacific coast of North America, as well as other regions. Humans who eat this fish improperly cooked are at risk of contracting the tapeworm parasite. The CDC is alerting medical professionals to this reality.

The CDC says that any tapeworm found in infected salmon from these regions could survive transportation if the fish isn't frozen. For this reason, medical professionals and parasitologists may find human infections in places where they're uncommon, including in the U.S., China, New Zealand, and Europe.

The Center concludes its report explaining:

For more effective control of this human foodborne parasite, detection of the sources of human infection (i.e., host associations), and critical revision of the current knowledge of the distribution and transmission patterns of individual human-infecting tapeworms are needed.