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About the Scientist

Judy Sakanari is a Japanese American parasitologist. She investigates worms and other parasites that live inside marine animals. Her work takes her to fish markets, sushi bars, and seal colonies in search of parasites that cause diseases in animals and humans. In her lab she conducts experiments to learn how parasites survive digestion and live out their life cycle.

Judy Sakanari

Biography of Judy Sakanari

Find out more about Judy on the Parasite Sleuth CD-ROM. The complete biography is 13 pages and includes a glossary.

A skinny, nine-year-old Japanese-American girl with short straight black hair walked down a slope to the creek where she and her two older brothers like to go fishing. As she got close to the pier, she saw a dead catfish floating in the water. Why had the fish died? Curiosity got the better of her. She picked up the catfish, pulled out a pocket knife she had borrowed from her Dad, and slit the fish open. Then she stood there staring in amazement at the fish's insides.

The little girl, Judy Sakanari, grew up to be a scientist at the University of California at San Francisco where she studies parasites that are found in fish. A parasite is an animal that lives on or inside another animal known as its host, and is dependent on the host for its food to survive. As a nine-year-old, Judy didn't know what a parasite was or what it looked like when she opened up that catfish. But now she regularly examines fish for parasites. One parasite she studies is a worm about an inch long that is found in fish.

Many animals have parasites. Dogs and cats can have parasites like ticks and fleas on their skin and roundworms and tapeworms inside. Humans can also get infected with parasites. "Basically I am interested in studying parasites and the relationships of the parasites with their hosts," Judy said. "One of the larger questions I am interested in answering is how parasites cause disease in humans."Judy Sakanari

Unlike the relationship between a parasite and its host, some relationships among animals are mutually beneficial. That means each needs the other, but each also helps the other. Judy gives one example of a "cleaning station" where shrimp position themselves on rocks: "A fish will come by and just open its mouth, and the shrimp will start picking the debris, bacteria, and parasites off the fish's gills, and off its skin. That way it benefits the fish because it's getting cleaned, and the shrimp also benefits because it's getting a meal."

However, the relationship parasites have with fish or animals is not mutually beneficial. The parasite benefits from living off its host, but the host often is harmed by the parasite. For example, parasites can cause large ulcers in the stomachs of marine animals. They can also make pets and people very sick.

(excerpted from the biography written by Mary Knudson, and the entire biography is available on the Parasite Sleuth CD-ROM.)

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This material is based upon work supported by the National Science Foundation under Grant No. 9909496.
Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and
do not necessarily reflect the views of the National Science Foundation (NSF).