More than 90 percent of popular freshwater game fish in Southern California contain a parasite that is capable of inducing strokes or heart attacks in the humans who eat them. Researchers said the parasites were two species of flatworms known as trematodes.

More than 90% of popular freshwater game fish in Southern California contain an introduced parasite capable of infecting humans, according to a new study by researchers at UC San Diego's Scripps Institution of Oceanography.

A study finds over 90% of Southern California freshwater game fish carry invasive trematode worms, posing potential health risks to humans. The study calls for more research to assess the public health implications.