August 18, 2006 - (SACRAMENTO) - With the recent identification of an unusual lung infection in two Orange County residents caused by a parasite found in raw, imported, freshwater crabs, State Public Health Officer Dr. Mark Horton today warned consumers that eating raw or undercooked freshwater crabs can cause serious illness.   

“Eating raw or undercooked freshwater crabs or crayfish can lead to rare lung fluke infection, a

serious  illness caused by the parasite Paragonimus,” said Horton.  “Do not eat raw or undercooked freshwater crabs or crayfish.”

Lung fluke infection is acquired more commonly in Asia and is not transmitted from person to person.

After freshwater crabs infected with the parasite are consumed, the parasite migrates from the intestines to the lung and may cause symptoms that include abdominal pain and diarrhea. After the parasite infects the lungs, symptoms can include cough, chest pain, difficulty breathing, fever and hives. The parasite can also migrate to other organs. Infection can last for years before symptoms develop. Medication is available to treat this infection. 

Individuals with the confirmed lung fluke infections reported eating live, raw, freshwater crabs, also referred to as Sawagani crabs, that were imported from Japan. These small crabs were about 2.5 inches across, including the legs. The crabs are usually served as tempura-battered and fried, but some consumers have eaten them raw.

An ongoing investigation by the California Department of Health Services (CDHS) has determined that this product may have been recently distributed to restaurants in at least 16 California counties: Alameda, El Dorado, Los Angeles, Marin, Napa, Orange, Riverside, Sacramento, San Bernardino, San Diego, San Francisco, San Luis Obispo, San Mateo, Santa Clara, Sonoma and Ventura.  CDHS is still investigating how these crabs are prepared and served at various restaurants.

Individuals who have eaten freshwater crabs imported from Japan raw or undercooked and have subsequently developed symptoms of abdominal pain, cough, chest pain, fever or hives should see their doctors for further evaluation.

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