Nearly 200 people in the San Francisco area have been sickened by the highly contagious Shigella bacteria, health officials say. The outbreak began 10 days ago at the Mariscos San Juan No. 3 restaurant, a Mexican seafood eatery in San Jose.

The intestinal disease caused by the bacteria, Shigellosis, has spread to people in six counties, according to the Santa Clara County Public Health Department (SCCPHD). Many of those who became ill required hospitalization and at least 12 are in intensive care, the SCCPHD reports.

“If you ate at Mariscos San Juan restaurant #3 (205 N. 4th Street in San Jose) on Friday or Saturday, October 16th or 17th, and you had sudden onset of diarrhea and fever within 1 to 2 days after eating there, please seek medical attention so that you can be tested and, if your symptoms are severe, receive treatment,” reads a statement from the SCCPHD.

As of last Friday, two lawsuits have been filed because of the outbreak, according to a Reuters report. The SCCPHD, which closed the restaurant, says their investigation is ongoing.

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People infected with Shigella develop diarrhea (sometimes bloody), a fever and stomach cramps within a day or two after they’re exposed to the bacteria, according to the Centers for Disease Control and Prevention (CDC). Symptoms last five to seven days in healthy people. The standard treatment is usually fluids and rest.

Young children and the elderly are most at risk. Shigella causes about 500,000 cases of diarrhea each year, the CDC says.

A person can be exposed to the bacteria by eating or drinking something that has come in contact with the stool of an infected person. For example, if you touch a surface contaminated by feces from an infected person and then touch your mouth, you may become infected. Food may be contaminated by food handlers or in growing fields that contain human sewage, the CDC says. Flies, which breed in feces, can also contaminate food they land on.

There’s no vaccine to prevent Shigellosis. However, you can lower your risk of becoming infected by washing your hands with soap and water before you eat and after changing a diaper, and avoiding sexual activity with anyone who recently had diarrhea, the CDC says.

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Angela is a Pulitzer Prize-winning digital editor with more than 15 years of experience delivering news and information to audiences worldwide. Prior to joining SafeBee, she was the features editor for Boston.com at The Boston Globe, overseeing health, travel, entertainment, business and lifestyle coverage. Before moving to features, she was the news and homepage editor, covering stories such as the Boston Marathon bombing, Red Sox World Series victories, presidential elections, a papal inauguration, and more. Her favorite safety tip: Clean your phone! The average cell phone has 18 times more germs than the toilet handle in a men’s restroom.